layer and no more bleeding. The teeth received aperiapical radiograph prior to extraction and wereextracted at 28 or 90 days. The teeth were evaluatedradiographically and histologically. These researchersconcluded that on the basis of symptomatic, clinical,radiographic, and histological findings, the CO2 lasercompares favorably to formocresol pulpotomies.

A study was performed comparing a conventionalformocresol–ZOE pulpotomy with a diode laser-MTA pulpotomy. In this study, the teeth werestudied clinically and radiographically for a periodof up to 15.7 months. The researchers concludedthat the laser-MTA pulpotomy showed slightlyreduced radiographic success rates compared to theformocresol–ZOE pulpotomy, but the results werenot statistically significant. They recommended thata larger sample with a longer follow-up was neededto consider the laser-MTA as an alternative to theformocresol–ZOE pulpotomy.127

In a study by Huth et al.,128 four pulpotomy techni-ques were compared: calcium hydroxide, Er:YAG,dilute formocresol, and ferric sulfate on a sample of200 primary molars treated and followed for up to 24months. The teeth were anesthetized and isolated witha rubber dam, and the caries was excavated and theroof of each pulp chamber removed with a diamondbur. The coronal pulp was removed with a slow-speedround bur and a spoon excavator. Hemostasis wasobtained by placing wet cotton pellets with slight pres-sure in the chamber for 5 minutes. Formocresol-medi-cated cotton pellets were applied to the pulp for 5 min-utes in the control group. In the laser group, the teethwere treated with an Er:YAG laser set at 2 Hz and180 mJ per pulses without water cooling. The meannumber of laser pulses per tooth was 31.5 ± 5.9. In thecalcium hydroxide group, the teeth were dressed withaqueous calcium hydroxide and covered with calciumhydroxide cement. In the last group, the teeth weretreated with cotton pellets wetted with ferric sulfate for15 seconds. All of the teeth received an IRM base,followed by a glass ionomer cement and a stainlesssteel crown, or a composite resin. The teeth werefollowed clinically and radiographically for up to 24months. After 24 months, the total (combined clinicaland radiographic success rates) and clinical success ratepercentages (in parenthesis) were as follows: formocre-sol 85 (96%), laser 78 (93%), calcium hydroxide 53(87%), and ferric sulfate 86 (100%). The authors con-cluded that calcium hydroxide was significantly lesseffective than formocresol. They also pointed out thatan increased sample size would be necessary before itcould be definitively said that this laser technique orferric sulfate was equal to, or better, than formocresol.

A study by Liu,129 which was conducted similarly tohis previously published case report, using anNd:YAG laser with follow-up for up to 64 monthsdemonstrated a 97% clinical success rate and a 94.1%radiographic success rate for the laser group that wascompared to the 85.5% clinical success rate and a78.3% radiographic success rate for the formocresolcontrol group.

Odabas et al.130 performed a clinical, radiographic,and histological study of Nd:YAG laser pulpotomiescompared to formocresol pulpotomies on 42 primaryteeth studied for a period of up to 12 months. Thisstudy was conducted nearly identically to the previousstudies. The laser group had a clinical success rate of85.71%, and a radiographic success rate of 71.42%, at9 and 12 months. The formocresol group had a clin-ical success rate of 90.47% and a radiographic successrate of 90.47% at 9 and 12 months. These researchersconclude that the Nd:YAG laser may be considered asan alternative to formocresol for pulpotomies forprimary teeth.

As lasers become more commonplace in dentistry,dentists who own a laser now have a body of researchliterature to justify the use of the laser to performpulpotomies for children in their practices.

Ferric Sulfate

The use of ferric sulfate as a primary tooth pulpotomymedicament begins to appear in the literature in thelate 1980s when Landau and Johnson131 published anabstract describing the use of ferric sulfate as a pulpmedicament in monkey’s teeth. The sample size wassmall and followed for only 60 days. They notedsecondary dentin formation and partial dentin brid-ging. They also described ferric sulfate as a ‘‘promis-ing medicament for teeth indicated for pulpotomies.’’Subsequently, Fei et al.132 presented the first clinicalstudy of ferric sulfate as a pulpotomy medicament forprimary teeth. In this study, 29 primary molarsreceived ferric sulfate pulpotomies and 27 received1:5 Buckley’s formocresol pulpotomies. Both groupsreceived a ZOE base and were followed over 12months. Criteria for clinical success included no symp-toms of pain, no tenderness to percussion, no swellingor fistula, and no pathological mobility. Criteria forradiographic success included normal periodontal liga-ment space, no pathological internal or external resorp-tion, and no furcal or apical radiolucency. Results ofthe study showed that after 1 year, 28 of 29 of the ferricsulfate-treated teeth were considered successful whileonly 21 of 27 of the formocresol-treated teeth were

Chapter 39 / Endodontic Therapy for Primary Teeth / 1415

considered successful. Combined overall success rateswere 96.6% for the ferric sulfate group and 77.8% forthe formocresol group. They raised some interestingpoints in their discussion. The use of ZOE as a base forformocresol pulpotomies is standard for this proce-dure. A ZOE base is also paired with ferric sulfate inorder to standardize the two pulpotomy treatments.The authors suggested that ZOE is appropriate forformocresol because the pulp tissue is somewhat fixedfrom formocresol and would not react with the slightlyirritating eugenol. Because ferric sulfate is not a tissuefixative, and probably leaves the tissue in a more vitalstate, using ZOE as a base introduces an irritant thatmay contribute to failure. They suggested that it wouldbe advisable to continue to study ferric sulfate as aprimary tooth pulp medicament for longer periods oftime and with more inert base materials.

Additional animal studies on rat and baboon teethhave been performed to assess histologically the pul-pal healing response after pulpotomy with ferric sul-fate and dilute formocresol. In her study using rats,Cotes133 had four test groups pairing ferric sulfateand dilute formocresol each with ZOE and polycar-boxylate cements. She demonstrated that in thecoronal third of the teeth tested, there was necrosisfor all groups tested. In the middle third, therewas a lesser degree of inflammation for the diluteformocresol–ZOE and ferric sulfate–polycarboxylategroups. In the apical third, the dilute formocresol–ZOEgroup showed the least inflammation. In addition,reparative dentin formation was noted in the apicalthird of the pulp in the ferric sulfate–ZOE groupwhile it was not found in the other groups. Conclu-sions from this study include the following: dilute

formocresol–ZOE produced the least inflammation,the use of polycarboxylate cement as a substitute forZOE did not improve the pulpal response, and sig-nificant differences were not found regarding thepulpal inflammation between ZOE and polycarbox-ylate cements.

Fuks et al.134 studied ferric sulfate and dilute for-mocresol pulpotomies in baboon teeth. Both medica-ments produced similar degrees of pulpal inflamma-tion and dentin bridging. Sixty percent of the teethhad normal pulps and the remaining 40% had severeinflammation. They recommended more clinicalstudy of ferric sulfate. A number of clinical studiescomparing ferric sulfate and formocresol pulpo-tomies have been performed. In 1997, Fuks et al.135

performed dilute formocresol and ferric sulfate pul-potomies and evaluated the teeth for up to 34months. They concluded that dilute formocresoland 15.5% ferric sulfate have similar success rates.Smith et al.136 performed a retrospective study ofclinical and radiographic data from the charts ofpatients who received ferric sulfate pulpotomies andZOE base. They followed 242 teeth for 4 to 57months (mean, 19 months). Their clinical successrate was 99% and the radiographic success rate was74% to 80%. The longer the teeth were followed,the more failures were noted radiographically. Themost common pathological radiographic observa-tions were calcific metamorphosis and internalresorption (Figure 11). Ninety percent of the teethsurvived after 3 years. They concluded that ferricsulfate has a success rate similar to dilute formocre-sol. In addition, if the radiographic changes are sepa-rated into dental and osseous categories, and the

A B C

Figure 11 A, Radiograph showing internal resorption in a primary molar after ferric sulfate pulpotomy. B, Resorption resulted in perforation (arrow).C, Perforated area resulting from the resorptive process (arrow).

1416 / Endodontics

dental changes (internal resorption and calcificmetamorphosis) are reclassified as acceptable varia-tions of success, then the radiographic success ratewould be 84% to 92%. The only radiographic changesthat would be classified as failures were interradicu-lar or periapical bone destruction and externalresorption. These investigators also suggest thatsince the goal is to keep the pulpotomized toothasymptomatic until exfoliation, some degree of den-tal changes is acceptable as long as it does not causepain or any symptoms.

Additional clinical and retrospective studies andone evidence-based assessment conclude that ferricsulfate and dilute formocresol have similar clinicaland radiographic rates of success.137–139 Vargas140

demonstrated that both ferric sulfate and formocresolpulpotomies can cause early exfoliation of the pulpo-tomized teeth with the subsequent need of spacemaintenance until the premolar erupts.

While most of the published studies on ferric sul-fate compare it to formocresol pulpotomy, Casaset al.141,142 took a different path, comparing it insteadto primary tooth root canal therapy (pulpectomy).Root canal therapy with a plain ZOE obturation andferric sulfate pulpotomy were found to have similarsuccess rates up to about 2 years, but past 2 years, theroot canal treatment had better success. They sug-gested that complete obturation of the canal ratherthan the partial treatment of the pulp is the besttreatment for pulpally involved primary teeth. Theydid concede that it will be difficult to get the pediatricdental community to change because of the relativelyhigh success rates of pulpotomy, because this was thetreatment they learned as a student or a resident, andbecause pulpotomy is a simple treatment and somechildren are not cooperative enough to sit for a pul-pectomy treatment (Figure 12).

Mineral Trioxide Aggregate

MTA has only recently been recommended as a pulpcapping agent in primary teeth. The first publishedclinical trials in primary teeth began in 2001 and inanimal studies occurred in 2003 to 2004 in rat and dogteeth.

A study involving rat first molars demonstratedthat after 2 weeks the treated teeth responded well toMTA and were attempting to form dentinal bridges.In the 4-week samples, dentin bridges were comple-tely formed at the pulp–MTA interface and the pulpsappeared normal.143 In the dog study, the researcherstested white and gray MTA as well as regular andwhite Portland cements as pulpotomy medicaments.Seventy-six teeth from mongrel dogs received pulpot-omy treatments. The teeth were evaluated after 120days and all four of the materials were found to havesimilar results. The pulps healed with dentin bridgesthat completely closed the pulpotomy access prepara-tions and the pulps appeared normal. The researchersconcluded that both MTA and Portland cement weregood pulp capping agents, and they further suggestedthat Portland cement has the potential to be used as aless expensive material in endodontics.144 They didnot address the fact that Portland cement is notapproved for human use.

A number of human studies using MTA as a pulpcapping material in primary teeth have demonstratedthat MTA performs as well or better than formocresol.Teeth in these studies were followed for periods of6 to 74 months. Pulp canal obliteration was a commonfinding in teeth treated with MTA. Various authorsconclude that MTA is a reasonable replacement forformocresol because of its high success rates and it lacksthe undesirable side effects of formocresol.145–150 Stu-dies that tested both gray and white MTA concludedthat the gray formulation produces better results thanthe white.146,150 While MTA has shown excellent resultsas a pulp capping agent for primary teeth pulpotomies,the one factor that seems to keep it from becoming thenew gold standard replacement for formocresol is thecost of the material. Only time will tell if MTA willreplace formocresol as the most commonly used pulpcapping material for primary teeth.

Nonvital Pulp Therapy for Children

In children, complete root canal treatment on primaryteeth is often referred to as a pulpectomy procedure.While the term pulpectomy only infers removal of thepulp, this term in pediatric dentistry has come to meanremoval of the caries and the inflamed or necrotic

Chapter 39 / Endodontic Therapy for Primary Teeth / 1417

pulp, cleaning and shaping the root canals, and obtura-tion of the tooth with a resorbable root filling material.Pulpectomy is indicated when a tooth has irreversiblepulpitis or a necrotic pulp or when a tooth has beentreatment planned for a pulpotomy and excessivehemorrhage (hyperemia) is encountered at the timeof treatment.1 Some pediatric dentists prefer pulpect-omy procedure for primary anterior teeth even if thetooth could be a candidate for only a pulpotomy

procedure or if the tooth has only reversible pulpitissymptoms because they believe a complete obturationof the canal is preferable to partial obturation wheneverpossible. A number of articles recommend pulpectomyas a substitute for all pulpotomies.151–153

Pulpectomy procedures for primary teeth must be donewith a consideration for the subjacent succedaneous tooth(Figure 13). It begins with profound pulpalanesthesia followed by placement of a rubber dam.

B C

D E F

A

Figure 12 Pulpotomy technique. A, Primary molar with large carious lesion. B, Caries removed and pulp exposed. C, Pulp tissue removed from thechamber. D, Pulp space being treated with ferric sulfate. E, After treatment with ferric sulfate. F, ZOE base has been placed.

1418 / Endodontics

All caries are removed with a slow-speed round buror a spoon excavator (Figure 14). From the pointof the pulp exposure, an access preparation is madeby connecting the pulp horns with the bur. Thiscreates the outline of the access preparation. Theroof of the chamber and the coronal pulp areremoved. The access preparation is refined to makesure that access to all of the canals is possible.There should be slight flaring of the access to allowfor ease of insertion of the files.

In clinical situations where a primary incisor has nocaries but has been affected by dental trauma thatcaused a gray discoloration, the access can be per-formed from the facial. It is very similar to a lingualaccess, as it connects the pulp horns and makes atriangular-shaped preparation that is combined with

a facial veneer preparation. Following pulpectomy,the tooth can be restored with a light composite resinin the pulp chamber to veneer the facial surface of thetooth to mask the discoloration.

To remove the radicular pulp in anterior teeth, agood technique is to insert two very small files (size 10or 15) on either side of the pulp and twist the filesremoving the whole pulp in one motion. In posteriorteeth, a barbed broach is used. The canals can beirrigated with sodium hypochlorite or sterile saline. Itwill be necessary to irrigate the canal several timesthroughout the procedure.

Files are measured 1 mm short of the apex bycomparing them to the length of the tooth on a radio-graph. This gives a preliminary working length. It isimportant to avoid extending instruments into the

Figure 14 Removal of the roof of the chamber and coronal pulp.Courtesy of Dr. A.C. Goerig.

Figure 13 Illustration shows the proximity of primary molar roots tosubjacent succedaneous tooth. Courtesy of Dr. A.C. Goerig.

Chapter 39 / Endodontic Therapy for Primary Teeth / 1419

apical area. The file is inserted into the canal and withtactile sense felt for an apical stop (Figure 15). Analternative method is to insert a medium or a large-sized file (medium for molars and larger files for ante-rior teeth) into the canal of the tooth and feel for anapical stop. This measurement is then compared to theradiograph. After the correct length is established,smaller files are set to this length. Studies have shownthat electronic apex locators can accurately be usedwhen treating primary teeth.154,155 Excessive cleaningand shaping of the canal should be avoided since thatcan damage the tooth and lead to extraction caused byperforation in the furcation or the lateral wall of acanal. The purpose of filing is to remove the pulp tissueand make room for the root canal filling material. Afterthe canals are cleaned, they should be irrigated againand dried with appropriately sized sterile paper points.

There are a number of choices of root canal fillingmaterials that can be used for primary teeth, and eachof these materials has an appropriate obturation tech-nique (Figure 16). Unreinforced zinc oxide and euge-nol is a very common material and is easily placed

into the canal with a rotary paste filler (Figure 17). Itis very important that commercially prepared zincoxide cements, with reinforcing fibers, not be used,as these reinforced cements are not well resorbed. Theunreinforced ZOE is mixed into a thick paste. Largerotary spirals work well for maxillary anterior teeth,and small spirals are suited for molars and mandibu-lar incisors. The rotary spiral is inserted into the canalwhile it is not turning and is used to search for theapical stop. The paste filler is then slightly removed sothat it is short of the apical stop and the handpiece isrevolved slowly. The dental assistant places the ZOEon the spatula next to the revolving paste filler thatpulls the ZOE off the spatula and introduces thecement into the canal. The speed of the handpiececan be adjusted to cause the ZOE to completely fill thecanal. When the dentist believes that the canal iscompletely filled, the paste filler is removed while stillrotating. If the paste filler is removed after it hasstopped, it will pull the ZOE from the canal.

A periapical radiograph is then exposed to deter-mine the adequacy of the root canal filling. If the

Figure 16 Pulpectomy treatment—obturation of the canals with zincoxide–eugenol (ZOE) placed with an instrument. Courtesy of Dr. A.C.Goerig.

Figure 15 Pulpectomy treatment—file inserted into the canal. Courtesyof Dr. A.C. Goerig.

1420 / Endodontics

canal is not completely filled, the paste filler is rein-troduced into the canal to achieve a better obtur-ation. Small amounts of ZOE overfill can be expected

to be resorbed uneventfully although it is better tohave an underfill than an overfill. The tooth is thenrestored and monitored until it exfoliates21,22,151,156

(Figures 18 and 19).There have been many articles that quantify the

success rate of pulpectomy and root canal treatmentsin primary teeth. In 1978, Jokinen et al.157 studied1,304 pulpectomies and found that only 53% weresuccessful. Success rates in the mandible and maxillawere nearly equal. This study is of historical interest,but it is difficult to use these results in judgingtoday’s dental care because the technique was verydifferent than the average pulpectomy that is per-formed today.

Flaitz et al.158 followed 87 pulpectomies in primaryincisors that were obturated with ZOE, with a drop offormocresol in the cement mixture, for a period of 37.4months. They found a success rate of 84%. In a follow-up study of 62 patients over a period of 12 to 74months, these same researchers demonstrated a successrate of 82.3% for primary molar pulpectomies with aZOE filling material.159 Yacobi153 et al. performed ZOEpulpectomies on both primary incisors and molars on51 children over a period of 12 months and found asuccess rate of 76% for the anterior teeth and a successrate of 84% for the posteriors. Payne et al.160 studiedprimary 253 anterior and posterior primary teeth for upto 24 months. Their success rate for anterior teeth was

Figure 17 Examples of rotary paste fillers.

Figure 18 Pulpectomy treatment—tooth restored with a stainless steelcrown. Courtesy of Dr. A.C. Goerig.

Chapter 39 / Endodontic Therapy for Primary Teeth / 1421

82.8% and 90.3% for posterior teeth. Coll et al.161

followed 65 ZOE pulpectomies for a period of 90.8months. The overall success rate was 77.7%. Two addi-tional studies provide success rates of 76% and 78.5%for ZOE pulpectomies.162,163

Rifkin164 used Kri Paste (a mixture of p-chlorophenol,camphor, menthol, and iodoform) to treat 45 primaryteeth. The teeth were treated in either 1 or 2 appointmentsdepending on the symptoms. After 1 year, 42 of the 45teeth were asymptomatic. Garcia-Godoy165 treated 55primary teeth with multiple appointment pulpectomies,obturated with Kri Paste, and followed for up to 2 years.There were no clinical or radiographic signs or symptomsin 95.6% of the teeth. Coll et al.166 compared 41 pulpec-tomies on primary teeth with pulp necrosis that wereobturated with Kri Paste over a period of up to 6 years 10months. The teeth had a success rate of over 80%. Anadditional study by Coll167 confirmed this success rate.Another study by Reyes and Reina168 with a similartechnique documented a 100% success rate. Thomaset al.169 studied 36 primary teeth for 3 months afterpulpectomies and obturated with iodoform paste.They found a success rate of 94.4%. Holan andFuks170 compared ZOE- and Kri Paste-filled pulpec-tomies on primary molars evaluated for periods up to48 months. They demonstrated a success rate of 84%for Kri Paste and 65% for ZOE. After a number ofclinical studies using Kri Paste for pulpectomies,Wright et al.171 performed an in vitro antimicrobialand cytotoxic study of Kri Paste and ZOE. In thisstudy, they found that ZOE had better antimicrobialactivity and that both materials had similar cytotoxi-city.

Hendry172 and his fellow researchers performedpulpectomies using calcium hydroxide and plainZOE on mongrel dogs. They exposed the pulps ofthe dogs to produce inflamed pulps. The teeth werelater instrumented and obturated with either calciumhydroxide or ZOE. Clinical, radiographic, and histo-

logical evaluations of both calcium hydroxide andZOE found that the calcium hydroxide specimenswere more successful in all areas. Another study byMani et al.173 compared 60 ZOE and calcium hydro-xide pulpectomies. Combined clinical and radio-graphic success rates were 83.3% for the ZOE groupand 86.7% for the calcium hydroxide group. Ozalpet al.174 found a success rate of 80 to 90% forpulpectomies that were obturated with calciumhydroxide.

Vitapex (NeoDental International, Inc., Federal Way,WA) is a commercially prepared calcium hydroxide andiodoform mixture that is prepackaged in syringes speci-fically for pulpectomies. It has been tested by a numberof researchers. A case report by Nurko et al.175 recom-mends it as an excellent material for pulpectomies inspite of some problems with resorption of the material.Three additional studies document the use of Vitapexwith follow-up of up to 22 months; the success ratesapproached 100%.162,174,176

One in vitro study by Tchaou et al.177 comparedvarious dental materials used in pulpectomies forprimary teeth for bacterial inhibition. They comparedcalcium hydroxide mixed with camphorated p-chlor-ophenol (Ca(OH)2 + CPC), calcium hydroxidemixed with sterile water (Ca(OH)2 + H2O), zincoxide mixed with CPC (ZnO + CPC), zinc oxidemixed with eugenol (ZOE), ZOE mixed with formo-cresol (ZOE + FC), zinc oxide mixed with sterilewater (ZnO + H2O), ZOE mixed with chlorhexidinedihydrochloride (ZOE + CHX), Kri paste, Vitapexpaste, and Vaseline. They found that the materialscould be divided into three groups. Category I withthe strongest antibacterial effect included ZnO +CPC, Ca(OH)2 + CPC, and ZOE + FC. Category IIwith a medium bacterial effect included ZOE +CHX, Kri, ZOE, and ZnO + H2O. Category III withno or minimal antibacterial effect included Vitapex,Ca(OH)2 + H2O, and Vaseline.

A B C

Figure 19 A, Primary molar with large caries lesion involving the pulp. B, Radiograph taken after pulpectomy and root canal filling. C, Evaluation 1 yearlater.

1422 / Endodontics

There are many articles that describe aspects of thepulpectomy technique and the instruments involvedin the procedure. Once a primary molar begins toresorb, from physiological resorption or from patho-sis, it can be difficult for the dentist to know if thecanals of the tooth can be properly instrumented oreven to obtain a correct working length. Rimondiniand Baroni178 studied 80 primary molars in children 4to 12 years old, 75 of which were extracted because ofpulpal involvement. The teeth were measured and theapices and areas of resorption were located. Theyfound that roots that were longer than 10 mm wererelated to a curved root shape with no externalresorption. Roots with length between 4 to 7 mm wereassociated with advanced root resorption. Roots thatwere shorter than 4 mm were associated with resorp-tion and perforation of the furcation. They identified4 mm as the limit of the length of a root that can betreated successfully.

Barr et al.179 presented the use of rotary nickel–ti-tanium files to prepare primary teeth for pulpectomytreatment. Advantages of this technique include easeof removal of tissue and debris, flexible design allow-ing access to canals, files prepare the canal in a funnelshape to ease obturation, and the files are available in21 mm length. Disadvantages of the use of these filesinclude cost of the equipment (handpiece), increasedcost of the files, and the time required to learn thetechnique. An in vitro study was performed on threepulpectomy filling devices: Lentulo spiral (DentsplyInternational), NaviTip (Ultradent Products, Inc.,South Jordan, UT), and Vitapex syringe (NeoDentalInternational, Inc.). Seventy extracted primary teethwere prepared and mounted in acrylic blocks. Theteeth were divided into three groups and pulpec-tomies were done followed by obturation with threedifferent methods. The specimens were radiographedand evaluated and the conclusion was that the Navi-Tip produced the best quality fill.180 Bawazir andSalama181 studied two methods of obturating rootcanals with Lentulo spiral paste fillers. One techniquewas with the Lentulo mounted on a slow-speed hand-piece and the other method was with a handheldLentulo. They concluded that there was no differencein the two methods as far as the quality of the fill or inthe success of the obturation.

Johnson et al.182 performed an in vitro study usingan apical resorbable collagen barrier to prevent over-fill of the canal. The apices of the teeth were coatedwith wax and the teeth were embedded into acrylic.The canals were filed, rinsed, and dried. A resorbablecollagen barrier was packed into some of the canalsand the remainder of the teeth served as controls. The

teeth were then obturated with Vitapex. Radiographswere evaluated for the presence of an overfill. In thetest group, overfills were present in 16% of teeth. Inthe control group (no barrier), overfills were presentin 42% of teeth. They suggest that resorbable collagenbarriers can help prevent overfills. One problem thatcan be experienced with resorbable cements placed inroot canals of primary teeth is overretention of thematerial in the alveolus after exfoliation of the pri-mary tooth (Figure 20). Studies by Sadrian andColl183 and Coll et al.166,167 have shown that ZOEcement was retained in the alveolus in 49.4% to73.3% of the exfoliated teeth, and this material wasstill retained in 27.3% of the patients after 40.2months. Short-filled pulpectomies were significantlyless likely to overretain ZOE.161 One of the two stu-dies evaluated over 6,000 charts in a pediatric dentis-try private practice.183 Jerrell and Ronk184 presented acase study of the arrest of eruption of a permanentpremolar after ZOE material was extruded from theprimary molar pulpectomy into the developing toothbud. Fortunately in the case of this particular patient,premolar extraction was a part of the patient’s ortho-dontic treatment plan, so the tooth was extracted. It isreassuring that studies have shown a low incidence ofenamel hypoplasia in succedaneous teeth when theprimary teeth have been treated with pulpectomytechniques.161,166

Educational Curricula and Attitudes

of Pediatric Dentists

A study by Avran185 in 1987 surveyed pediatric den-tistry residencies in Canada and a number of dentalschools worldwide. He found that in Canada amongpediatric dental specialists, the preferred pulp med-icament for 50% of the respondents was 1:5 formo-cresol and full-strength formocresol was preferredby 42.2%. In Canadian pediatric dental residencyprograms, full-strength formocresol was preferredby 40.8% of respondents and 1:5 formocresol waspreferred by 36%. Seventy percent of respondentsin Scandinavian dental schools preferred calciumhydroxide. This is not unexpected since much ofthe research on calcium hydroxide as a pulp medica-ment has been done there. When respondents wereasked if they were considering a change to anothermedicament, many said they would consider glutar-aldehyde.

A second study was published by Primosch186 in1997 based on a survey of the pediatric dental

Chapter 39 / Endodontic Therapy for Primary Teeth / 1423

programs in the United States regarding curricula forpulp therapy in children. Calcium hydroxide was thepreferred base for pulp capping. Most schools taughtthat after the first appointment of an indirect pulpcap, it would be necessary to reenter the tooth only ifthe patient experienced symptoms. A 1:5 dilution offormocresol was the most commonly (71.7%) recom-mended medicament for pulpotomy procedure, and itwas left in the tooth for 5 minutes (94.3%). ZOE wasthe most commonly recommended base (92.4%). It isinteresting to note that while some practitioners wereconsidering changing from formocresol to glutaralde-hyde in Avram’s study in the 1980s, no US dentalschool included glutaraldehyde in the curriculum inthe 1997 study. Further, the Primosh’s study reportedthat 2 of 53 dental schools in 1997 were teaching ferricsulfate or 1:5 formocresol to their students. While

interest in glutaraldehyde has decreased, interest andresearch on ferric sulfate has greatly increased.

In regard to pulpectomy procedure, 98% of US dentalschools were teaching hand instrumentation of canals,with the majority of schools not recommending any enlar-gement of the canal. The most commonly recommendedirrigants were sodium hypochlorite, sterile water or saline,and local anesthetic. Ninety percent of schools recom-mended zinc oxide and eugenol as the preferred fillingfor root canals. These two studies have now become out-dated. So why include this information? These are onlytwo journal articles that quantify what is being taught indental schools. It is important to realize that for-mocresol has been advocated as a pulp medicamentfor a very long time, and it seems to be veryentrenched in pediatric dental education. While itmay have a number of problems, no substitute has

A B

C D

Figure 20 A, Large caries on primary incisors at the time of diagnosis. B, Approximately 3 years after endodontic treatment. C, Five and half years aftertreatment, the primary tooth is retained and deflecting permanent successor. D, The primary incisor has been extracted. Radiograph shows retained zincoxide–eugenol (ZOE) material. The right primary incisor was subsequently extracted.

1424 / Endodontics

been overwhelmingly advocated to take its place. Itis certain that there is much room for research onnew pulp medicaments to replace formocresol.

Conclusion

Endodontic therapy, from pulp capping, pulpotomyor to pulpectomy, is an excellent procedure to preventthe premature loss of primary teeth. When the appro-priate treatment is selected for each situation, successand preservation of the tooth can be anticipated. Vitalpulp therapy is indicated when the pulp has the poten-tial for healing, and nonvital pulp therapy is indicatedwhen irreversible pulpitis or necrosis exists. Preservingprimary teeth keeps young smiles beautiful and dentalarches intact preventing space loss and malocclusion.

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3. Puddhikarant P, Rapp R. Radiographic anatomy of pulpalchambers of primary molar. Pediatr Dent 1983;5(1):25–9.

4. Goto G, Zhang Y. Study of cervical pulp horns in humanprimary molars. J Clin Pediatr Dent 1995;20(1):41–4.

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6. Ringelstein D, Seow WK. The prevalence of furcation foraminain primary molars. Pediatr Dent 1989;11(3):198–202.

7. Paras LG, Rapp R, Piesco NP, et al. An investigation ofaccessory foramina in furcation areas of human primarymolars: Part 1 SEM observations of frequency, size andlocation of accessory foramina in the internal and externalfurcation areas. J Clin Pediatr Dent 1993;17(2):65–9.

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167. Coll JA, Josell S, Nassof S, et al. An evaluation of pulpal therapyin primary incisors. Pediatr Dent 1988;10(3):178–84.

168. Reyes AD, Reina ES. Root canal treatment in necrotic pri-mary molars. J Pedod 1989;14(1):36–9.

169. Thomas AM, Chandra S, Chandra S, Pandey RK. Elimina-tion of infection in pulpectomized deciduous teeth: a short-term study using iodoform paste. J Endod 1994;20(5):233–5.

170. Holan G, Fuks AB. A comparison of pulpectomies usingZOE and Kri paste in primary molars: a retrospective study.Pediatr Dent 1993;15(6):403–7.

171. Wright KJ, Barbosa SV, Araki K, Spangberg LSW. In vitroantimicrobial and cytotoxic effects of Kri 1 paste and zincoxide–eugenol used in primary tooth pulpectomies. PediatrDent 1994;16(2):102–6.

172. Hendry JA, Jeansonne BG, Dummett CO, Burrell W.Comparison of calcium hydroxide and zinc oxideeugenol pulpectomies in primary teeth of dogs. Oral SurgOral Med Oral Pathol Oral Radiol Endod 1982;54(4):445–51.

173. Mani SA, Chawla HS, Tewari A, Goyal A. Evaluation ofcalcium hydroxide and zinc oxide eugenol as root canalfilling materials in primary teeth. J Dent Child 2000;67(2):142–7.

174. Ozalp N, Saroglu I, Sonmez H. Evaluation of various rootcanal filling materials in primary molar pulpectomies: an invivo study. Am J Dent 2005;18(6):347–50.

175. Nurko C, Ranly DM, Garcia-Godoy F, Lakshmyya KN.Resorption of a calcium hydroxide/iodoform (Vitapex) inroot canal therapy for primary teeth: a case report. PediatrDent 2000;22(6):517–20.

176. Nurco C, Garcia-Godoy F. Evaluation of a calcium hydro-xide/iodoform paste (Vitapex) in root canal therapy forprimary teeth. J Clin Pediatr Dent 1999; 23(4):289–94.

177. Tchaou WS, Turng BF, Minah GE, Coll JA. In vitro inhibition ofbacteria from root canals of primary teeth by various dentalmaterials. Pediatr Dent 1995;17(5):351–5.

178. Rimondini L, Baroni C. Morphologic criteria for root canaltreatment of primary molars undergoing resorption. EndodDent Traumatol 1995;11(3):136–41.

179. Barr ES, Kleier DJ, Barr NV. Use of nickel–titanium rotaryfiles for root canal preparation in primary teeth. PediatrDent. 1999;21(7):453–4. Also reprinted in Pediatr Dent2000;22(1):77–8.

180. Guelman M, McEachern M, Turner C. Pulpectomies inprimary incisors using three delivery systems: an in vitrostudy. J Clin Pediatr Dent 2004;28(4):323–6.

181. Bawazir OA, Salama FS. Clinical evaluation of root canal obtura-tion methods in primary teeth. Pediatr Dent 2006;28(1):39–47.

182. Johnson MS, Britto LR, Guelmann M. Impact of a biologicalbarrier in pulpectomies of primary molars. Pediatr Dent2006;28(6):506–10.

183. Sadrian R, Coll JA. A long-term follow-up on the retentionrate of zinc oxide eugenol filler after primary tooth pulpect-omy. Pediatr Dent 1993;15(4):249–53.

184. Jerrell RG, Ronk SL. Developmental arrest of a succedaneoustooth following pulpectomy in a primary tooth. J Pedod1982;6(4):337–42.

185. Avran DC, Pulver F. Pulpotomy medicaments for vital pri-mary teeth ASCD J Dent Child 1989;56(6):426–34.

186. Primosch RE, Glomb TA, Jerrell RG. Primary tooth pulptherapy as taught in predoctoral pediatric dental programsin the United States. Pediatr Dent 1997;19(2):118–22.

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CHAPTER 40

RESTORATION OF ENDODONTICALLY TREATED

TEETH

CHARLES J. GOODACRE, NADIM Z. BABA

Various methods of restoring pulpless teeth have beenreported for more than 200 years. In 1747, PierreFauchard1 described the process by which roots ofmaxillary anterior teeth were used for the restorationof single teeth and the replacement of multiple teeth(Figure 1). Posts were fabricated of gold or silver andheld in the root canal space with a heat-softenedadhesive called ‘‘mastic.’’1,2 The longevity of restora-tions made using this technique was attested to byFauchard: ‘‘Teeth and artificial dentures, fastenedwith posts and gold wire, hold better than all others.They sometimes last fifteen to twenty years and evenmore without displacement. Common thread andsilk, used ordinarily to attach all kinds of teeth orartificial pieces, do not last long.’’1

The replacement crowns were made from bone,ivory, animal teeth, and sound natural tooth crowns.Gradually the use of these natural substances declined,to be slowly replaced by porcelain. A pivot (what istoday termed a post) was used to retain the artificialporcelain crown into a root canal and the crown–postcombination was termed a ‘‘pivot crown.’’ Porcelainpivot crowns were described in the early 1800s by awell-known dentist of Paris, Dubois de Chemant.2

Pivoting (posting) of artificial crowns to natural rootsbecame the most common method of replacing arti-ficial teeth and was reported as the ‘‘best that can beemployed’’ by Chapin Harris in The Dental Art in1839.3

Early pivot crowns in the United States used sea-soned wood (white hickory) pivots.4 The pivot wasadapted to the inside of an all-ceramic crown and alsointo the root canal space. Moisture would swell thewood and retain the pivot in place.2 Surprisingly,Prothero2 reported removing two central incisorcrowns with wooden pivots that had been successfully

used for 18 years. Subsequently, pivot crowns werefabricated using wood/metal combinations and thenmore durable all-metal pivots were used. Metal pivotretention was achieved by various means such asthreads, pins, surface roughening, and split designs thatprovided mechanical spring retention.2

Unfortunately, adequate cements were not availableto these early practitioners, cements that would haveenhanced post retention and decreased abrasion ofthe root caused by movement of metal posts withinthe canal. One of the best representations of a pivotedtooth appears in Dental Physiology and Surgery, writ-ten by Sir John Tomes in 1849 (Figure 2).5 Tomes’ postlength and diameter conformed closely to today’s prin-ciples in fabricating posts.

Endodontic therapy, by these dental pioneers, emb-raced only minimal efforts to clean, shape, and obturatethe canal. Frequent use of the wooden posts in emptycanals led to repeated episodes of swelling and pain. Woo-den posts, however, did allow the escape of the so-called‘‘morbid humors.’’ A groove in the post or the root canalprovided a pathway for continual suppuration from theperiradicular tissues.1

Although many of the restorative techniques usedtoday had their inception in the 1800s and early1900s, proper endodontic treatment was negle-cted until years later. Today, both endodontic andprosthodontic aspects of treatment have advancedsignificantly, new materials and techniques have beendeveloped, and a substantial body of scientific knowl-edge is available upon which to base clinical treatmentdecisions.

The purpose of this chapter is to answer questionsfrequently encountered when dental treatment involvesendodontically treated teeth and to describe the tech-niques commonly employed when restoring these

1431

teeth. Whenever possible, the answers and discussionwill be supported by scientific evidence. Conflictingresults will be presented to provide a comprehensiveunderstanding of the available evidence.

Should Crowns Be Placed on

Endodontically Treated Teeth?

A retrospective study6 of 1,273 teeth endodonti-cally treated 1 to 25 years previously comparedthe clinical success of anterior and posterior teeth.Endodontically treated teeth with restorations thatencompassed the tooth (onlays, partial or completecoverage metal crowns, and metal ceramic crowns)were compared with endodontically treated teethwith no coronal coverage restorations. It was deter-mined that coronal coverage crowns did not sig-nificantly improve the success of endodonticallytreated anterior teeth. This finding supports theuse of a conservative restoration such as an etchedresin restoration in the access opening of otherwiseintact or minimally restored anterior teeth. Crownsare indicated only on endodontically treated ante-rior teeth when they are structurally weakened bythe presence of large and/or multiple coronalrestorations or they require significant form/colorchanges that cannot be effected by bleaching, resinbonding, or porcelain laminate veneers. Scurriaet al.7 collected data from 30 insurance carriers in45 states regarding the procedures 654 generaldentists performed on endodontically treated teeth.The data indicated that 67% of endodonticallytreated anterior teeth were restored without acrown, supporting the concept that many anteriorteeth are being satisfactorily restored without theuse of a crown.

When endodontically treated posterior teeth (withand without coronal coverage restorations) were com-pared, a significant increase in the clinical success wasnoted when cuspal coverage crowns were placed onmaxillary and mandibular molars and premolars.6 In astudy of 116 failed and extracted endodontically trea-ted teeth, Vire8 reported that teeth restored withcrowns had greater longevity than uncrowned teeth.A strong association was found between crown place-ment and the survival of endodontically treated teeth.If long-term tooth survival is the primary goal, placing

Figure 2 Principles used today in selecting post length and diameterwere understood and taught by early practitioners during mid-1800s.

Figure 1 Early attempts to restore single or multiple units. A, ‘‘Pivottooth’’ consisting of crown, post, and assembled unit. B, Six-unit ante-rior fixed partial dental prosthesis ‘‘pivoted’’ in lateral incisors withcanines cantilevered. Crowns were fashioned from a diversity of materi-als. Human, hippopotamus, sea horse, and ox teeth were used, as wellas ivory and oxen leg bones. Posts were usually made from preciousmetals and fastened to the crown and root by using a heated sticky‘‘mastic’’ prepared by gum, lac, turpentine, and white coral powder.

1432 / Endodontics

a crown on an endodontically treated posterior toothenhances survival (Figure 3).9 Therefore, restorationsthat encompass the cusps should be used on poster-ior teeth that have intercuspation with opposingteeth and thereby receive occlusal forces that pushthe cusps apart. The previously discussed insurancedata7 indicated that 37 to 40% of posterior endo-dontically treated teeth were restored by practitionerswithout a crown, a method of treatment not sup-ported by the long-term clinical prognosis of poster-ior endodontically treated teeth that do not havecusp-encompassing crowns. There are, however, cer-tain posterior teeth (not as high as 40%) that do nothave substantive occlusal intercuspation or have anocclusal form that precludes intercuspation of a nat-ure that attempts to separate the cusps (such asmandibular first premolars with small, poorly devel-oped lingual cusps). When teeth are intact or mini-mally restored (small MO or DO restorations), theywould be reasonable candidates for restoration ofonly the access opening without the use of a coronalcoverage crown.10

In contrast to the above recommendations, a 3-yearclinical study by Mannocci et al.11 evaluated the clin-ical success rate of endodontically treated premolarsrestored with a post and direct composite resinrestorations with and without complete crown cover-age. They found that both had a similar success rate.Nagasiri et al.,12 in a retrospective cohort study, indi-cated that when endodontically treated molars are

completely intact except for a conservative accessopening, they could be restored successfully by usingcomposite resin restorations.

Multiple clinical studies of fixed partial dentures,many with long spans and cantilevers, have deter-mined that endodontically treated abutments failedmore often than vital teeth due to tooth fracture,13–17

supporting the greater fragility of endodontically trea-ted teeth and the need to design restorations thatreduce the potential for both crown and root fractureswhen extensive fixed prosthodontic treatment isrequired.

Gutmann18 reviewed the literature and presented anoverview of several articles that identify what happenswhen teeth are endodontically treated. These articlesprovide background information important to anunderstanding of why coronal coverage crowns helpprevent fractures of posterior teeth. Endodonticallytreated dog teeth have been found to have 9% lessmoisture than vital teeth.19 In addition, it was foundthat dehydration increases stiffness and decreases theflexibility in teeth. However, dehydration by itself doesnot account for the physical property changes in den-tin.20 Also, with aging, greater amounts of peritubulardentin are formed, which decreases the amount oforganic materials that may contain moisture. It hasbeen shown that endodontic procedures reduce toothstiffness by 5%, attributed primarily to the access open-ing.21 Tidmarsh22 described the structure of an intacttooth that permits deformation when loaded occlusally

A B

Figure 3 A, Occlusal view showing the fracture of the buccal cusp of an endodontically treated mandibular left first molar. B, Extracted tooth showingthe fracture extending down both roots.

Chapter 40 / Restoration of Endodontically Treated Teeth / 1433

and elastic recovery after removal of the load. The directrelationship between tooth structure removed duringtooth preparation and tooth deformation under loadhas been described.23 Dentin from endodontically trea-ted teeth has been shown to exhibit significantly lowershear strength and toughness when compared with vitaldentin.24 Rivera et al.25 stated that the effort required tofracture dentin may be less when teeth are endodonti-cally treated because of more immature (potentiallyweaker) collagen intermolecular cross-links. In a recentstudy, it was found that collagen fibrils degradedover time in teeth with zinc phosphate-cemented posts.Acid demineralization can also occur from bacteria andacid etching.26

CONCLUSIONSRestorations that encompass the cusps of endodonti-cally treated posterior teeth have been found toincrease the clinical longevity of these teeth. There-fore, crowns should be placed on endodontically trea-ted posterior teeth that have occlusal intercuspationwith opposing teeth of the nature that places expan-sive forces on the cusps. Since crowns do not enhancethe clinical success of anterior endodontically treatedteeth, their use on relatively sound teeth should belimited to situations where esthetic and functionalrequirements cannot be adequately achieved by othermore conservative restorations (Figure 4).

With Pulpless Teeth, Do Posts Improve

Long-Term Clinical Prognosis

or Enhance Strength?

Historically, the use of posts was based on the conceptthat a post reinforces the tooth.

LABORATORY DATAVirtually all laboratory studies27–37 have shown thatplacement of a post and core either fails to increase thefracture resistance of endodontically treated extractedteeth or decreases the fracture resistance of the toothwhen a force is applied via a mechanical testingmachine. Lovdahl and Nicholls27 found that endodon-tically treated maxillary central incisors were strongerwhen the natural crown was intact except for the accessopening than when they were restored with cast postsand cores or pin-retained silver amalgams. Lu28 foundthat posts placed in intact endodontically treated cen-tral incisors did not lead to an increase in the forcerequired to fracture the tooth or in the position andangulation of the fracture line. Pontius29 found thatmaxillary incisors, without posts, resisted higher fail-ure loads than the other groups with posts and crowns.Gluskin30 found that mandibular incisors with intactnatural crowns exhibited greater resistance to trans-verse loads compared with teeth with posts and cores.McDonald31 found no difference in the impact frac-ture resistance of mandibular incisors with or withoutposts. Eshelman and Sayegh32 reported similar resultswhen posts were placed in extracted dog lateral incisors.Guzy and Nicholls33 determined that there was no sig-nificant reinforcement achieved by cementing a postinto an endodontically treated tooth that was intactexcept for the access opening. Leary et al.34 measuredthe root deflection of endodontically treated teethbefore and after posts of various lengths were cementedinto prepared root canals. They found no significantdifferences in strength between the teeth with or with-out a post. Trope et al.35 determined that preparing apost space weakened endodontically treated teeth com-pared with ones in which only an access opening wasmade, but no post space.

A potential situation where a post and core couldstrengthen a tooth was identified by Hunter et al.36

using photoelastic stress analysis. They determinedthat removal of internal tooth structure during endo-dontic therapy is accompanied by a proportionalincrease in stress. They also determined that minimalroot canal enlargement for a post does not substan-tially weaken a tooth but when excessive root

Figure 4 Traumatized tooth before endodontic procedure. Placement ofa bonded resin restoration in the access opening after root canaltreatment and whitening is the only treatment required since crownsdo not enhance the longevity of anterior endodontically treated teeth. Acrown will be indicated only when esthetic and functional needs cannotbe achieved through more conservative treatments.

1434 / Endodontics

canal enlargement has occurred, a post strengthensthe tooth. Therefore, if the walls of a root canal arethin due to the removal of internal root caries oroverinstrumentation during post preparation, then apost may potentially strengthen the tooth.

Two-dimensional finite element analysis was usedin one study37 to determine the effect of posts ondentin stress in pulpless teeth. When loaded verticallyalong the long axis, a post reduced maximal dentinstress by as much as 20%. However, only a small (3 to8%) decrease in dentin stress was found when a toothwith a post was subjected to masticatory and trau-matic loadings at 45� to the incisal edge. The authorsproposed that the reinforcement effect of posts isdoubtful for anterior teeth because they are subjectedto angular forces.

CLINICAL DATASorensen and Martinoff38 evaluated endodonticallytreated teeth with and without posts and cores. Someof the teeth were restored with single crowns whileothers served as fixed partial denture abutments orremovable partial denture abutments. Posts and coressignificantly decreased the clinical success rate of teethwith single crowns, improved the clinical success ofremovable partial denture abutment teeth, and hadlittle influence on the clinical success of fixed partialdenture abutments. Eckerbom et al.39 examined theradiographs of 200 consecutive patients and reexa-mined the patients radiographically 5 to 7 years laterto determine the prevalence of apical periodontitis. Ofthe 636 endodontically treated teeth evaluated, 378had posts and 258 did not have posts. At both exam-inations, apical periodontitis was significantly morecommon in teeth with posts than in endodonticallytreated teeth without posts. Morfis40 evaluated theincidence of vertical root fracture in 460 endodonti-cally treated teeth, 266 of which had posts. There were17 teeth with root fracture after a time period of atleast 3 years. Nine of the 17 fractured teeth had postsand 8 root fractures occurred in teeth without posts.Morfis40 concluded that the endodontic technique cancause vertical root fracture. In an analysis of data frommultiple clinical studies, Goodacre41 found that 3% ofteeth with posts fractured. None of these clinical dataprovide definitive support for the concept that postsand cores strengthen endodontically treated teeth orimprove their long-term prognosis.

THE PURPOSE OF POSTSSince clinical and laboratory data indicate that teethare not strengthened by posts, their purpose is for

retention of a core that will provide appropriate sup-port for the definitive crown or prosthesis. Unfortu-nately, this primary purpose has not been completelyrecognized. Hussey42 noted that 24% of general dentalpractitioners felt that a post strengthens teeth. A 1994survey (with responses from 1066 practitioners andeducators) revealed some interesting facts. Ten per-cent of the dentist respondents felt that every endo-dontically treated tooth should receive a post. It wasdetermined that 62% of dentists over age 50 believed apost reinforces the tooth whereas only 41% of thedentists under age 41 believed in that concept.Thirty-nine percent of part-time faculty, 41% of full-time faculty, and 56% of nonfaculty practitioners feltthat posts reinforce teeth.43

CONCLUSIONSBoth laboratory and clinical data fail to provide defi-nitive support for the concept that posts strengthenendodontically treated teeth. Therefore, the purposeof a post is to provide retention for a core.

What Is the Clinical Failure Rate

of Posts and Cores?

Several studies provide clinical data regarding thenumber of posts and cores that failed over certain timeperiods44–55 (Table 1). When this number is divided bythe total number of posts and cores placed, a failure

Table 1 Clinical Failure Rate of Posts andCores

Lead Author Study LengthPercentage ofClinical Failure

Turner (1982)* 5 years 9 (6 of 66)Sorenson (1984) 1–25 years 9 (36 of 420)Bergman (1989)* 6 years 9 (9 of 96)Weine (1991)* 10 years or more 7 (9 of 138)Hatzikyriakos (1992)* 3 years 11 (17 of 154)Mentink (1993)* 1–10 years (mean 4.8) 8 (39 of 516)Wallerstedt (1984)* 4–10 years (mean 7.8) 14 (8 of 56)Torbjorner (1995) 4–5 years 9 (72 of 788)Balkenhol (2006) 1–9 years (mean 2.1) 7 (50 of 802)Valderhaug (1997) 1–25 years (mean 2.1) 10 (40 of 397)Mean values§ 8 years 9 (292 of

3433)

*Studies used to calculate mean study length.§Calculation made by averaging numerical data from all studies.

Chapter 40 / Restoration of Endodontically Treated Teeth / 1435

percentage is determined. A 9% overall average forfailure was calculated by averaging the failure percen-tages from 10 studies (an average study length of6 years). In these studies, the failure percentage rangedfrom 7% to 14%.

A review of more specific details from the 10 stu-dies provides insight into the length of each study andthe number of posts and cores evaluated. The findingsof a 5-year retrospective study of 66 posts and coresindicate there were 6 failures and a 9% failure rate.44

Another study found that 17 of 154 posts failed after3 years for an 11% failure rate.45 A failure rate of 9%was found in three studies.46–48 Two studies reporteda 7% post and core failure rate after 9 years ormore.49,55 An 8% failure rate (39 of 516 posts andcores) was published when 516 posts and cores placedby senior dental students were retrospectively evalu-ated,50 whereas another study recorded a 14% failurerate (8 failures in 56 posts and cores) from posts andcores placed by dental students.51 A study of 397 postsfollowed for 25 years reported a 10% post and corefailure rate after 25 years (40 of 397 posts failed).54

Kaplan-Meier survival statistics (percentage ofsurvival over certain time periods) were presentedor could be calculated from the data in nine studies52

(Table 2). The survival rates ranged from a high of

99% after 10 years or more of follow-up to a 78%survival rate after a mean time of 5.2 years. Thefailure percentage per year has also been calculatedand ranged from 1.56% per year47 to 4.3% peryear.53

CONCLUSIONSPosts and cores had an average clinical failure rate of9% (7 to 14% range) when the data from 10 studieswere combined (average study length of 8 years).

What Are the Most Common Types

of Post and Core Failures?

Eight studies indicate that post loosening is themost common cause of post and core fail-ure44,45,47,48,50,55–57 (Figure 5). Turner44 reported on100 failures of post-retained crowns and indicatedthat post loosening was the most common type offailure. Of the 100 failures, 59 were caused by postloosening. The next most common occurrences were42 apical abscesses followed by 19 carious lesions.There were 10 root fractures and 6 post fractures. Inanother paper by Turner,56 he reported the findingsof a 5-year retrospective study of 52 post-retainedcrowns. Six posts had come loose, which was themost common failure. Lewis and Smith57 presenteddata regarding 67 post and core failures after 4 years.Forty-seven of the failures resulted from post loosen-ing, 8 from root fractures, 7 from caries, and 4 frombent or fractured posts. Bergman et al.47 found 8failures in 96 posts after 5 years. Six posts had loo-sened and 2 roots had fractured. Hatzikyriakos et al.45

reported on 154 posts and cores after 3 years. Fiveposts had come loose, five crowns had come loose,four roots fractured, and caries caused three failures.Mentink50 identified 30 post loosenings and 9 toothfractures when evaluating 516 posts and cores over a 1-to 10-year time period (4.8 years mean study length).Torbjorner et al.48 reported on the frequency of threetechnical failures (loss of retention, root fracture, andpost fracture). They did not report biological failures.Loss of retention was the most frequent post failure,accounting for 45 of the 72 post and core failures. Root

Table 2 Kaplain–Meier Survival Data (%) ofPosts and Cores

Lead Author Study LengthPercentageof Survival

Robert (1970) 5.2 years mean 78Wallerstedt (1984) 4–10 years range 86Sorenson (1985) 1–25 years range 90Weine (1991) 10 years or more 99Hatzikyriakos (1992) 3 years 92Mentink (1993) 1–10 years (mean 4.8) 82Creugers (1993)

(meta-analysis)6 years 81 (threaded

posts), 91(cast posts)

Balkenhol (2006) 1–9 years range(mean 2.1)

89

Valderhaug (1997) 1–25 years range 80

1436 / Endodontics

fracture (Figure 6) was the second most common fail-ure cause followed by post fracture. Balkenhol et al.55

reported on 802 posts and cores over a 10-year period.

Thirty-nine posts had loosened, eight had longitudinalroot fracture, and six had transverse root fracture.

In two studies, factors other than loss of retentionwere listed as the most common cause of failure.46,49

Sorensen and Martinoff46 evaluated 420 posts andcores and recorded 36 failures. Of the 36 failures, 8were related to restorable tooth fractures, 12 to non-restorable tooth fractures, 13 to loss of retention, and 3were caused by root perforations. Weine et al.49 found9 failures in 138 cast posts and cores after 10 years ormore. Three failures were caused by restorative proce-dures, two by endodontic treatment, two by period-ontal problems, and two by root fractures. No postsfailed due to loss of retention.

Four studies have provided data on the incidence oftooth fracture but no information regarding post loosen-ing. Linde58 reported that 3 of 42 teeth fractured, Ross59

found no fractures with 86 posts, Morfis40 found that 10of 266 teeth fractured, and Wallerstedt51 identified 2fractures with 56 posts.

Loss of retention and tooth fracture (in that orderof occurrence) are the 2 most common causes offailure when these studies are collectively analyzedby averaging the numerical data from all the studies.Five percent of the posts placed (144 of 2,980 posts)

A B

Figure 5 Post and crown loosened from maxillary canine a few years after placement. A, Both the post/core and the crown came off. B, Clinical photoshows very little cervical tooth structure for retention of the crown.

Figure 6 Radiograph of a fractured maxillary first premolar with a postwith excessive diameter and insufficient length, two problems frequentlyseen in conjunction with fractured roots.

Chapter 40 / Restoration of Endodontically Treated Teeth / 1437

experienced loss of retention (Table 3). Two percentof the posts placed (82 of 3,827 posts) failed viatooth fracture (Table 4).

CONCLUSIONSLoss of retention and tooth fracture are the two mostcommon causes of post and core failure.

Which Post Design Produces the Greatest

Retention?

LABORATORY DATAThere have been many laboratory studies comparingthe retention of various post designs. Threaded postsprovide the greatest retention, followed by cemented,

Table 3 Clinical Loss of Retention Associated with Posts and Cores

Lead Author Study Length

Percentage of Posts

Placed that Loosened Post Form

Percentage of

Failures Owing to

Loosening

Turner (1982) 5 years 9 (6 of 66) Appeared to be tapered *

Turner (1982) 1–5 years or more * Tapered 59 (59 of 100)

Sorensen (1984) 1–25 years 3 (13 of 420) Tapered and parallel 36 (13 of 36)

Lewis (1988) 4 years * Threaded, tapered, and parallel 70 (47 of 67)

Bergman (1989) 6 years 6 (6 of 96) Tapered 67 (6 of 9)

Weine (1991) 10 years or more 0 (0 of 138) Tapered 0 (0 of 9)

Hatzikyriakos (1992) 3 years 3 (5 of 154) Threaded, tapered, and parallel 29 (5 of 17)

Mentink (1993) 1–10 years (mean 4.8) 6 (30 of 516) Tapered 77 (30 of 39)

Torbjorner (1995) 4–5 years 6 (45 of 788) Tapered and parallel 63 (45 of 72)

Balkenhol (2006) 1–9 years (mean 2.1) 5 (39 of 802) Tapered 43 (39 of 90)

Mean values§ 5 (144 of 2980) 56 (244 post

loosenings

of 439 total

failures)

*Data not available in publication.§Calculation made by averaging numerical data from all studies.

Table 4 Clinical Tooth Fractures Associated with Posts and Cores

Lead Author Study Length

Percentage of Teeth

Restored withPosts that Fractured

Post Form(s)Studied

Percentage of FailuresOwing to Fracture

Turner (1982) 5 years 0 (0 of 66) Appeared to be tapered *

Turner (1982) 1–5 years or more * Tapered, parallel, and threaded 10 (10 of 100)

Sorensen (1984) 1–25 years 3 (12 of 420) Tapered and parallel 33 (12 of 36)

Linde (1984) 2–10 years (5 years, 8 months mean) 7 (3 of 42) Threaded 38 (3 of 8)

Lewis (1988) 4 years * Threaded, tapered, and parallel 12 (8 of 67)

Bergman (1989) 6 years 3 (3 of 96) Tapered 33 (3 of 9)

Ross (1980) 5 years or more 0 (0 of 86) Tapered, parallel, and threaded 0 (0 of 86)

Morfis (1990) 3 years at least 4 (10 of 266) Threaded and parallel *

Weine (1991) 10 years or more 1 (2 of 138) Tapered 50 (2 of 4)

Hatzikyriakos (1992) 3 years 3 (4 of 154) Threaded, tapered, and parallel 3 (4 of 17)

Mentink (1993) 1–10 years (mean 4.8) 2 (9 of 516) Tapered 23 (9 of 39)

Wallerstedt (1984) 4–10 years (mean 7.8) 4 (2 of 56) Threaded 25 (2 of 8)

Torbjorner (1995) 4–5 years 3 (21 of 788) Tapered and parallel 29 (21 of 72)

Balkenhol (2006) 1–9 years (mean 2.1) 2 (14 of 802) Tapered 15 (14 of 90)

Valderhaug (1997) 1–25 years (mean 2.1) 1 (2 of 397) Tapered 5 (2 of 40)

Mean values§ 2 (82 of 3827) 16 (90 tooth fractures

of 576 total failures)

*Data not available in publication.§Calculation made by averaging numerical data from all studies.

1438 / Endodontics

parallel-sided posts. Tapered cemented posts are theleast retentive. Cemented, parallel-sided posts withserrations are more retentive than cemented, smooth-sided parallel posts. These laboratory data are dis-cussed below.

CLINICAL DATAThere is clinical support for these laboratory studies.Torbjorner et al.48 reported significantly greater loss ofretention with tapered posts (7%) compared with par-allel posts (4%). Sorensen and Martinoff46 determinedthat 4% of tapered posts failed by loss of retentionwhereas 1% of parallel posts failed in that manner.Turner56 indicated that tapered posts loosened clini-cally more frequently than parallel-sided posts. Lewisand Smith57 also found a higher loss of retention withsmooth-walled tapered posts than parallel posts. Berg-man et al.47 and Mentink et al.50 evaluated only taperedposts, and both studies reported that 6% of taperedposts failed via loss of retention, values higher thanthose recorded by Torbjorner et al.48 and Sorensenand Martinoff46 for parallel posts.

Contrasting results were reported by Weine et al.49

They found no clinical failures from loss of retentionwith cast tapered posts. Hatzikyriakos et al.45 studiedtapered threaded posts, parallel cemented posts, andtapered cemented posts. The only posts that loosenedfrom the root were parallel cemented posts.

CONCLUSIONSTapered posts are the least retentive and threadedposts the most retentive in laboratory studies. Mostof the clinical data support the laboratory findings.

Is There a Relationship Between Post

Form and the Potential for Root

Fracture?

LABORATORY DATAUsing photoelastic stress analysis, Henry60 deter-mined that threaded posts produced undesirablelevels of stress. Another study used strain gaugesattached to the root and compared four parallel-sided threaded posts with one parallel-sided non-threaded post.59 Two of the threaded posts producedthe highest strains, whereas two other threaded postscaused strains comparable to the nonthreaded post.Standlee et al.,61 using photoelastic methods, indi-

cated that tapered, threaded posts were the worststress producers. When three types of threaded postswere compared in extracted teeth, Deutsch et al.62

found that tapered threaded posts increased rootfracture by 20 times that of the parallel threadedposts (Figure 7).

Laboratory testing of split threaded posts has pro-vided varying results, but more research groups haveconcluded that they do not reduce the stress asso-ciated with threaded posts. Thorsteinsson et al.63

determined that split threaded posts did not reducestress concentration during loading. In another study,split threaded posts were found to produce installa-tion stresses comparable to other threaded posts.64

Greater stress concentrations than those of someother threaded posts were reported under simulatedfunctional loading.65–67 Rolf et al.68 found that a splitthreaded post produced comparable stress to one typeof threaded post and less stress than a third threadedpost design. Ross et al.59 determined that a splitthreaded post produced less root strain than twoother threaded posts and comparable strain to a thirdthreaded post and a nonthreaded post. Anotherresearch group69 concluded that the split threadeddesign reduced the stresses caused during cementationcompared with a rigid threaded post design. Multiplephotoelastic stress studies have concluded that postsdesigned for cementation produced less stress thanthreaded posts.60,61,68

When parallel-sided cemented posts were com-pared with tapered cemented posts, photoelastic stresstesting results generally favored parallel-sided posts.Using this methodology, Henry60 found that parallel-

Figure 7 Radiograph showing a threaded post that may have causedroot fracture in the second premolar.

Chapter 40 / Restoration of Endodontically Treated Teeth / 1439

sided posts distribute stress more evenly to the root.Finite element analysis studies produced similarresults.70,71 Two additional photoelastic studies63,66

concluded that parallel posts concentrate stress api-cally and tapered posts concentrate stress at the post–core junction. Also using photoelastic testing, Assifet al.72 found that tapered posts showed equal stressdistribution between the cementoenamel junction andthe apex compared with parallel posts that concen-trated the stress apically.

When fracture patterns in extracted teeth were usedto compare parallel and tapered posts, the evidencefavoring parallel posts was less favorable. Sorensen andEngelman73 determined that tapered posts caused moreextensive fractures than parallel-sided posts did, but theload required to create fracture was significantly higherwith tapered posts. Lu,28 also using extracted teeth,found no difference in the fracture location betweenprefabricated parallel posts and cast posts and cores.Assif et al.74 tested the resistance of extracted teeth tofracture when the teeth were restored with either parallelor tapered posts and complete crowns. No significantdifferences were noted, and post design did not influ-ence fracture resistance.

In analyzing the stress distribution of posts, it wasnoted that tapered posts generate the least cementationstress and should be considered for teeth that have thinroot walls, are nearly perforated, or have perforationrepairs.66

CLINICAL DATAThere are several clinical studies that provide datarelated to the incidence of root fracture associatedwith different post forms. Some of these studies pro-vide a comparison of multiple post forms, whereasother studies evaluated only one type of post. Com-bining all the root fracture data for each post formfrom both types of studies reveals some interestingtrends (Table 5). Five studies present data regardingroot fractures and threaded posts,40,46,51,58,75 fourregarding fractures associated with parallel-sidedcemented posts40,46,48,75 and nine related to taperedcemented posts.40,46–49,50,54,55,75 If the total number ofthreaded posts evaluated in the five studies is dividedinto the total number of fractures found withthreaded posts, a percent value can be determinedthat represents the average incidence of tooth fractureassociated with threaded posts in the five studies. Thesame data can be calculated for parallel cemented andtapered cemented posts, permitting a comparison ofthe root fracture incidences associated with thesethree post forms.

Combining the five studies that reported data relativeto threaded posts produced a mean fracture rate of 7%(11 fractures from 169 posts). The four clinical studiesthat contain fracture data from parallel-sided cementedposts produced a mean fracture incidence of 1%(9 fractures from 687 posts). From the seven studiesreporting root fracture with tapered posts, there is amean fracture rate of 2% (66 root fractures from2,752 posts). This combined study data support thepreviously cited photoelastic laboratory stress tests,indicating that the greatest incidence of root frac-tures occurred with threaded posts and that the low-est incidence of root fracture was associated withparallel cemented posts. In a meta-analysis ofselected clinical studies, Creugers et al.52 calculateda 91% tooth survival rate for cemented cast posts andcores and an 81% survival rate for threaded postswith resin cores.

While the combined data from all the studies for eachtype of post revealed certain trends, analysis of indivi-dual studies (where multiple post forms were comparedin the same study) produced less conclusive results. Onestudy of threaded posts and cemented posts determinedthat teeth with threaded posts were lost more frequentlythan teeth with cast posts.39 In three other clinicalcomparisons of threaded and cemented posts, no toothfracture differences were noted.40,45,75 In addition to thecomparisons of threaded and cemented posts, four clin-ical studies provide data comparing the tooth fractureincidences associated with parallel-sided and taperedposts. In comparing parallel and tapered posts byreviewing dental charting records, a higher failure ratewas reported with tapered posts than with parallel posts

Table 5 Post Form and Tooth Fracture

Clinical Data (Percentage of Post and Cores Studied that Failedvia Tooth Fracture)

Threaded Posts(Lead Author)

Parallel-Sided Posts

(Lead Author)

Tapered Posts

(Lead Author)

40 (2 of 5) (Sorensen) 0 (0 of 170)

(Sorensen)

7 (18 of 245) (Sorensen)

0 (0 of 10) (Ross) 2 (5 of 332)

(Torbjorner)

4 (16 of 456) (Torbjorner)

4 (2 of 56) (Wallerstedt) 0 (0 of 39) (Ross) 1 (2 of 138) (Weine)

7 (3 of 42) (Linde) 3 (4 of 146) (Morfis) 2 (9 of 516) (Mentink)

7 (4 of 56) (Morfis) 3 (3 of 96) (Bergman)

0 (0 of 38) (Ross)

3 (2 of 64) (Morfis)

2 (14 of 802) (Balkenhol)

1 (2 of 397) (Valderhaug)

7% Mean* (11 of 169) 1% Mean* (9 of 687) 2% Mean* (66 of 2752)

*Calculation made by averaging numerical data from all studies.

1440 / Endodontics

in two studies, and the failures were judged to be moresevere with tapered posts.46,48 Two other clinical studiesdetermined that there were no differences between taperedand parallel-sided posts.48,75 Hatzikyriakos et al.45 foundno significant differences between 47 parallel cementedposts and 44 tapered cemented posts after three years ofservice. Ross75 evaluated 86 teeth with posts and cores thathad been restored at least five years previously. No fracturedifferences were found between 38 tapered cemented postsand 39 parallel cemented posts.

Unfortunately, the total number of clinical studiesthat compared multiple post forms in the same studyis limited. Also, several factors may have affected thefindings of available studies. Two of the papers thatcontained a comparison of multiple post forms cov-ered sufficiently long time periods (10 to 25 years)that the tapered cemented posts may have been inplace for much longer time periods than the paral-lel-sided cemented posts (due to the later introduc-tion of parallel posts into the dental market).46,48 Themean time since the placement of each post form wasnot identified in these studies. Also, both of thesestudies were based on reviews of patient records(rather than clinical examinations) and depended onthe accuracy of dental charts in determining if andwhen posts failed as well as the cause of the failure.Another factor that affected the results of many of thereferenced clinical studies was the length of the posts.For instance, in Sorensen and Martinoff’s study,46

44% of the tapered cemented posts had a length thatwas half (or less than half) the incisocervical/occluso-cervical dimension of the crown whereas only 4% ofthe parallel cemented posts were that short. Sinceshort posts have been associated with higher rootstresses in laboratory studies, the difference in postlength may have affected their findings where toothfractures occurred with 18 of 245 tapered posts com-pared with no fractures with 170 parallel posts.

CONCLUSIONSWhen evaluating the relationship between post formand root fracture, laboratory tests generally indicatethat all types of threaded posts produce the greatestpotential for root fracture. When comparing taperedand parallel cemented posts by using photoelasticstress analysis, the results generally favor the parallelcemented posts. However, the evidence is mixed whenthe comparison between tapered and parallel posts isbased on fracture patterns in extracted teeth createdby applying a force via a mechanical testing machine.

When evaluating the combined data from multipleclinical studies, threaded posts generally produced the

highest root fracture incidence (7%) compared withtapered cemented posts (2%) and parallel cementedposts (1%). Analysis of individual clinical studies asopposed to the combined data produces less conclu-sive results. Additional comparative clinical studieswould be beneficial, including designs that have notyet been evaluated in comparative studies.

What Is the Proper Length for a Post?

A wide range of recommendations have been maderegarding post length, which includes the following:

1. The post length should equal the incisocervical orocclusocervical dimension of the crown.76–83

2. The post should be longer than the crown.84

3. The post should be one-third of the crownlength.85

4. The post should be half of the root length.86,87

5. The post should be two-thirds of the rootlength.88–92

6. The post should be four-fifths of the rootlength.93

7. The post should be terminated halfway betweenthe crestal bone and the root apex.94–96

8. The post should be as long as possible withoutdisturbing the apical seal.60

A review of scientific data provides the basis for dif-ferentiating between these varied guidelines.

While short posts have never been advocated,they have been frequently observed during radio-graphic examinations (Figures 8 and 9). Grieve and

Figure 8 Radiograph displaying a very short post in the distal root of afirst molar. The prosthesis has loosened.

Chapter 40 / Restoration of Endodontically Treated Teeth / 1441

McAndrew97 found that only 34% of 327 postswere as long as the incisocervical length of thecrown. In a clinical study of 200 endodonticallytreated teeth, Ross75 determined that only 14% ofposts were two-thirds or more of the root lengthand 49% of the posts were one-third or less of theroot length. A radiographic study of 217 postsdetermined that only 5% of the posts were two-thirds to three-fourths of the root length.98 In aretrospective clinical study of 52 posts, Turner44

radiographically compared the length of the postwith the maximal length available if 3 mm ofgutta-percha was retained. Posts that came looseused only 59% of the ideal length and only 37% ofthe posts were longer than the proposed maximallength. Nine millimeters was proposed as the ideallength. Short posts have been associated withhigher root stresses36,64,66,70,71 and a greater ten-dency for root fracture to occur.

Sorensen and Martinoff46 determined that the clin-ical success was markedly improved when the post wasequal to or greater than that of the crown length.

Johnson and Sakumura99 determined that posts thatwere three-fourths or more of the root length were upto 30% more retentive than posts that were half of theroot length or equal to the crown length. Leary et al.100

indicated that posts with a length at least three-fourthsof the root offered the greatest rigidity and least rootbending.

These data indicate that post length would appropri-ately be three-fourths that of the root length. However,some interesting results occur when post length guide-lines of two-thirds to three-fourths of the root lengthare applied to teeth with average, long, and short rootlengths. It was determined that a post approaching thisrecommended length range is not possible withoutcompromising the apical seal by retaining less than5 mm of gutta-percha.101 When post length was halfthat of the root, the apical seal was rarely compromisedon average length roots. However, when posts weretwo-thirds of the root length, many of the average andshort roots would have less than the optimal gutta-percha seal. Shillingburg et al.102 also indicated thatmaking the post length equal to the clinical crownlength can cause the post to encroach on the 4-mm‘‘safety zone’’ required for an apical seal.

Abou-Rass et al.103 proposed a post length guide-line for maxillary and mandibular molars based onthe incidence of lateral root perforations when postpreparations were made in 150 extracted teeth. Theydetermined molar posts should not be extended morethan 7 mm apical to the root canal orifice.

When teeth have diminished bone support, stressesincrease dramatically and are concentrated in thedentin near the post apex.104 A recent finite elementmodel study established a relationship between postlength and alveolar bone level.105 To minimize stressin the dentin and in the post, the post should extendmore than 4 mm apical to the bone.

CONCLUSIONSReasonable clinical guidelines for length include thefollowing:

1. Make the post approximately three-fourths of thelength of the root when treating long-rootedteeth.

2. When average root length is encountered, postlength is dictated by retaining 5 mm of apicalgutta-percha and extending the post to thegutta-percha (Figure 10).

Figure 9 Radiograph of a second premolar with a very short post; thelack of adequate retention for the core can result in the prosthesisloosening.

1442 / Endodontics

3. Whenever possible, posts should extend at least 4 mmapical to the bone crest to decrease dentin stress.

4. Molar posts should not be extended more than7 mm into the root canal apical to the base of thepulp chamber (Figure 11).

How Much Gutta-Percha Should

Be Retained to Preserve the

Apical Seal?

It has been determined that when 4 mm of gutta-percha was retained, only 1 of 89 specimens showedleakage, whereas 32 of 88 specimens leaked whenonly 2 mm of gutta-percha was retained.106 Twostudies found no leakage at 4 mm,107,108 and twoadditional studies found little leakage at4 mm.106,109 Portell et al.110 found that most speci-mens with only 3 mm of apical gutta-percha hadsome leakage. When the leakage associated with 3,5, and 7 mm of gutta-percha was compared, Mat-tison et al.111 found significant leakage differencesbetween each of the dimensions. They proposedthat at least 5 mm of gutta-percha is required foran adequate apical seal. Nixon et al.112 comparedthe sealing capabilities of 3, 4, 5, 6, and 7 mm ofapical gutta-percha using dye penetration. Thegreatest leakage occurred when only 3 mm wasretained, and it was significantly different fromthe other groups. They also noted a significantdecrease in leakage when 6 mm of gutta-percharemained. Raiden and Gendelman113 cementedstainless steel posts with zinc phosphate cement inteeth with residual root canal fillings of 1, 2, 3, and4 mm. They tested apical leakage using a passivedye system. They concluded that 4 mm of apicalseal provided a leakage value of zero. Kvist et al.114

examined radiographs from 852 clinical endodontictreatments. Posts were present in 424 of the teeth.Roots with posts in which the remaining root fill-ing material was shorter than 3 mm showed asignificantly higher frequency of periapical radiolucen-cies. Using a pressure-driven tracer assay, Wu et al.115

and Abramovitz et al.116 found that 4 or 5 mm ofapical seal was inferior in their ability to preventleakage, compared with an original full-length rootcanal filling. Similarly, Metzger et al.117 comparedthe sealing capabilities of 3, 5, 7, and 9 mm ofapical gutta-percha using a pressure-driven radio-active tracer assay. They concluded that the sealingis proportional to the length of the remaining fill-ing and that original full-length root canal fillingshave a superior seal compared with 3, 5, and 7 mmof apical gutta-percha.

Figure 10 Five millimeters of gutta-percha was retained in the maxillarypremolar and the post extended to that point.

Figure 11 The post in the distal canal of the mandibular molar extendsto a maximal length of 7 mm.

Chapter 40 / Restoration of Endodontically Treated Teeth / 1443

CONCLUSIONSSince there is greater leakage when only 2 to 3 mm ofgutta-percha is present (Figure 12), 4 to 5 mm shouldbe retained apically to ensure an adequate seal.Although studies indicate that 4 mm produces anadequate seal, stopping precisely at 4 mm is difficultand radiographic angulation errors could lead toretention of less than 4 mm. Therefore, 5 mm ofgutta-percha should be retained apically. This seal iscomplemented by the seal provided by the post andcore, and the overlying crown (Figure 11).

Does Post Diameter Affect Retention and

the Potential for Tooth Fracture?

Studies relating post diameter to post retention havefailed to establish a definitive relationship. Two stu-dies determined that there was an increase in postretention as the diameter increased,102,118 whereasthree studies found no significant retention changeswith diameter variations.119,110,120 Krupp et al.121

indicated that post length was the most importantfactor affecting retention and post diameter was asecondary factor.

A more definitive relationship has been establishedbetween post diameter and stress in the tooth. Mat-tison122 found that as the post diameter increased,stress increased in the tooth. Trabert et al.123 mea-sured the impact resistance of extracted maxillarycentral incisors as post diameter increased and foundthat increasing the post diameter decreased thetooth’s resistance to fracture. Deutsch et al.62 deter-mined that there was a six-fold increase in the poten-tial for root fracture with every millimeter decreasein tooth diameter. However, two finite element stu-dies failed to find higher tooth stresses with larger-diameter posts.70,71

CONCLUSIONSLaboratory studies relating retention to post dia-

meter have produced mixed results, whereas a moredefinitive relationship has been established betweenroot fracture and large-diameter posts (Figure 13).

Figure 12 Less than 2 mm of gutta-percha remains in the maxillary firstpremolar apical to the cast post and core, increasing the risk of failure.

A B

Figure 13 Excessive post diameters. A, Large-diameter post placed in the palatal root of the maxillary molar. B, Large-diameter threaded post causedfracture of the maxillary second premolar. The radiographic appearance of the bone is typical of a fractured root—a teardrop-shaped lesion with diffuseborder.

1444 / Endodontics

What Is the Relationship Between

Post Diameter and the Potential for Root

Perforations?

In a literature review of guidelines associated with postdiameter, Lloyd and Palik124 indicated that there arethree distinct philosophies of post space preparation.One group advocates the narrowest diameter for fabri-cation of a certain post length (the conservationists).Another group proposes a space with a diameter thatdoes not exceed one-third of the root diameter (theproportionists). The third group advises leaving at least1 mm of sound dentin surrounding the entire post (thepreservationists).

Based on the proportional concept of one-third of theroot diameter, three articles measured the root diametersof extracted teeth and proposed post diameters thatwould not exceed this proportion.102,103,125 Tilk et al.125

examined 1,500 roots. They measured the narrowestmesiodistal dimension at the apical, middle, and cer-vical one-thirds of the teeth except the palatal root ofthe maxillary first molar that was measured faciolin-gually. Based on the 95% confidence level that postwidth would not exceed one-third of the apical widthof the root, they proposed the following post widths(Table 6): small teeth such as mandibular incisors (0.6to 0.7 mm); large-diameter roots such as maxillarycentral incisors and the palatal root of the maxillaryfirst molar (1.0 mm); and for the remaining teeth (0.8to 0.9 mm).

Shillingburg et al.102 measured 700 root dimensionsto determine the post diameters that would minimizethe risk of perforation. Also based on not exceedingone-third of the mesiodistal root width, they recom-mended the following post diameters (see Table 6):mandibular incisors (0.7 mm); maxillary central inci-sors or other large roots (1.7 mm—which was themaximal recommended dimension); post tip diameter(at least 1.5 mm less than the root diameter at thatpoint); and post diameter at the middle of the rootlength (2.0 mm less than the root diameter).

Post spaces were prepared in 150 extracted maxil-lary and mandibular molars by using different instru-ment diameters and the resulting incidences ofperforations were recorded.103 The authors deter-mined that the mesial roots of mandibular molarsand the buccal roots of maxillary molars should notbe used for posts due to the higher risk of perforationon the furcation side of the root. For the principal

roots (mandibular distal and maxillary palatal), theydetermined that posts should not be extended morethan 7 mm into the root canal (apical to the pulpchamber) due to the risk of perforation. Regardinginstrument size, they concluded that post prepara-tions can be safely completed by using a No. 2 Peesoinstrument, but perforations are more likely when thelarger Nos. 3 and 4 Peeso instruments are used.

Raiden et al.126 evaluated several instrument dia-meters (0.7, 0.9, 1.1, 1.3, 1.5, and 1.7 mm) to deter-mine which one(s) would preserve at least 1 mm ofroot wall thickness following post preparation in max-illary first premolars. They determined that instru-ment diameter must be small (0.7 mm or less) formaxillary first premolars with single canals becausethe mesial and distal developmental root depressionsrestrict the amount of available tooth structure in thecentrally located single root canal. However, whenthere are dual canals, the instrument can be as largeas 1.1 mm because the canals are located buccally andlingually into thicker areas of the roots.

CONCLUSIONSInstruments used to prepare posts should be relatedin size to root dimensions to avoid excessive postdiameters that lead to root perforation (Figure 14).Safe instrument diameters to use are 0.6 to 0.7 mmfor small teeth such as mandibular incisors and 1 to

Table 6 Post Space Preparation Widths (in Millimeters)

Maxillary Mandibular

Tilket al

Shillingburget al

Tilket al

Shillingburget al

Central incisor 1.1 1.7 0.7 0.7

Lateral incisor 0.9 1.3 0.7 0.7

Canine 1.0 1.5 0.9 1.3

First premolar

(B) 0.9 0.9

(L) 0.9 0.9

Second premolar 0.9 1.1 0.9 1.3

First molar

(MB) 0.9 1.1 (MB) 0.9 1.1

(DB) 0.8 1.1 (ML) 0.8 0.9

(L) 1.0 1.3 (D) 0.9 1.1

Second molar

(MB) - 1.1 (MB) - 0.9

(DB) - 0.9 (ML) - 0.9

(L) - 1.3 (D) - 1.1

Chapter 40 / Restoration of Endodontically Treated Teeth / 1445

1.2 mm for large-diameter roots such as the max-illary central incisors. Molar posts longer than 7 mmhave an increased chance of perforations and there-fore should be avoided even when using instrumentsof an appropriate diameter.

Can Gutta-Percha Be Removed

Immediately after Endodontic Treatment

and a Post Space Prepared?

Several studies indicate that there is no difference in theleakage of the root canal filling material when the postspace is prepared immediately after completing endo-dontic therapy.107,109,127,128 Bourgeois and Lemon127

found no difference between immediate preparation ofa post space and preparation 1 week later when 4 mm ofgutta-percha were retained. Zmener109 found no differ-ence in dye penetration between gutta-percha removalafter 5 minutes and 48 hours. Two sealers were testedand 4 mm of gutta-percha was retained apically.When lateral condensation of gutta-percha was used,Madison and Zakariasen107 found no difference in thedye penetration between immediate removal and 48-hour removal. Using the chloropercha filling technique,Schnell128 found no difference between immediate

removal of gutta-percha and no removal of gutta-percha.By contrast, Dickey et al.129 found significantly greaterleakage with immediate gutta-percha removal.

Kwan and Harrington130 tested the effect of immedi-ate gutta-percha removal using both warm instrumentsand rotary instruments. There was no significant dif-ference between the controls and immediate removalusing warm pluggers and files. Compared with thecontrols, there was significantly less leakage withimmediate removal of gutta-percha when using GatesGlidden drills.

Karapanou et al.131 compared immediate and delayedremoval of two sealers (a zinc oxide–eugenol-basedsealer and a resin-based sealer). No difference betweenimmediate and delayed removal was noted with theresin-based sealer, but delayed removal of the zinc oxi-de–eugenol-based sealer produced significantly greaterleakage. Abramovitz et al.116 compared immediategutta-percha removal using hot pluggers and delayedgutta-percha removal (after 2 weeks) using Gates Glid-den drills. They found no difference between the twomethods.

Portell et al.132 found that delayed gutta-percharemoval (after 2 weeks) caused significantly more leakagethan immediate removal when only 3 mm of gutta-percha was retained apically. Fan et al.133 found moreleakage from delayed removal of gutta-percha. Solanoet al.134 found a less significant difference in apical leakagebetween teeth whose post spaces were prepared at thetime of the obturation and 1 week later using warm gutta-percha condensation and AH Plus sealer.

CONCLUSIONSAdequately condensed gutta-percha can be safelyremoved immediately after endodontic treatment.

What Instruments Remove Gutta-Percha

Without Disturbing the Apical Seal?

Three methods have been advocated for the removalof gutta-percha during preparation of a post space:chemical (oil of eucalyptus, oil of turpentine, andchloroform), thermal (electrical or heated instru-ments), and mechanical (Gates Glidden drills, Peesoreamers, etc.). The chemical removal of gutta-perchafor post space preparation is not utilized forspecific reasons (microleakage, inability to controlremoval).111,127 However, thermal and mechanical

Figure 14 Excessive post diameter in the maxillary second premolarcreated a perforation in the mesial root concavity. Note the distinctborder and round form of the radiolucent lesion, characteristics indica-tive of a root perforation.

1446 / Endodontics

techniques or a combination of both are routinelyused.

Multiple studies have determined that there is nodifference in leakage between removing gutta-perchawith hot instruments and removing it with rotaryinstruments.106,111,135 Suchina and Ludington135 andMattison et al.111 found no difference between hotinstrument removal and removal with Gates Gliddendrills. Camp and Todd106 found no difference betweenPeeso reamers, Gates Glidden drills, and hot instru-ments. Hiltner et al.136 compared warm pluggerremoval with two types of rotary instruments (GPXburs and Peeso reamers). There were no significantdifferences in dye leakage between any of the groups.Contrasting results were found by Haddix et al.137 Theymeasured significantly less leakage when gutta-perchawas removed with a heated plugger than when either aGPX instrument or Gates Glidden drills were used.DeCleen138 found that it is desirable to remove gutta-percha using a heated instrument first, and then using asmall Gates Glidden drill. Using a pressure-drivenradioactive tracer assay, Abramovitz et al.116 found nodifference in apical leakage between hot pluggers andGates Glidden drills. Balto et al.139 compared two meth-ods of gutta-percha removal and their impact on apicalleakage. They found that removing gutta-percha withPeeso reamers showed less leakage compared with usinga hot plugger.

CONCLUSIONSBoth rotary instruments and hot hand instrumentscan be safely used to remove adequately condensedgutta-percha when 5 mm is retained apically.

Can a Separated Instrument Be Removed

During Post Space Preparation and Still

Maintain the Apical Seal?

Following root canal therapy, the endodontically trea-ted tooth could present with a separated instrument(files, rotary instruments, etc.) in any part of thecanal. Attempts to remove these fragments prior topost space preparation could lead to loss of apical seal,perforations, ledge formation, and/or over enlarge-ment of the canal. A decision to bypass or removethe fragment will depend on the type and position ofthe broken instrument and should be determined byan endodontist with the use of an operating micro-scope.

Bypassing fractured instruments seems to be the bestapproach. Hulsmann and Schinkel140 reported anoverall success rate of 68% when bypassing brokeninstruments from canals in vivo. Ward et al.141

reported an overall success rate of 73%. Suter et al.142

with the use of an dental operating microscope wereable to achieve an overall success rate of 87% whenremoving broken instruments.

CONCLUSIONSIf a separated fragment of any instrument cannot beremoved from the canal during post space prepara-tion, it should be bypassed or left in the canal.

Can a Portion of a Silver Point

Be Removed and Still Maintain the

Apical Seal?

In one study, all the specimens leaked when 1 mm of a5-mm long silver point was removed by using a roundbur.109 Neagley108 found that removal of the fillingmaterial coronal to the silver point with a Peeso reamercaused no leakage. However, when all the filling mate-rials and 1 mm of the silver point were removed,complete dye penetration occurred in eight of ninespecimens.

CONCLUSIONSThe removal of a portion of a silver point during postpreparation causes apical leakage.

How Soon should the Definitive

Restoration Be Placed After Post

Space Preparation?

ONE-PIECE PROVISIONAL RESTORATIONIt is well established that a deficient root canal obtura-tion and a poor coronal restoration will potentiallyallow endotoxins, bacteria, and saliva to penetrate theroot canal causing periapical inflammation.143–149

Provisional restorations are mainly used to providethe patient with a functional and esthetic restoration.They also protect the hard and soft tissues prior toplacement of the definitive restoration. However, pro-visional restorations are considered restorations withpoor coronal seal. Several studies indicate that there issignificant coronal leakage when the tooth is restored

Chapter 40 / Restoration of Endodontically Treated Teeth / 1447

with a provisional restoration.139,150–153 Demarchiet al.150 found that a tooth restored with a temporarypost–crown combination had significantly greaterleakage than definitively cemented prefabricated postsand separate crowns. Similar results were found by Foxet al.151 when they compared cast posts and corescemented with zinc phosphate cement, prefabricatedposts and composite resin cores cemented with resincement, and provisional post–crowns cemented withzinc oxide–eugenol cement. In a 3-year retrospectiveclinical study, Lynch et al.152 evaluated 176 endodonti-cally treated teeth. They found that the loss of endo-dontically treated teeth occurred more often with thoseteeth restored with provisional restorations. Followingthese results, several studies139,151 suggested that thedefinitive post and restoration should be cemented assoon as possible to prevent recontamination of the rootcanal. However, to minimize leakage and enhancelong-term success, the definitive coronal restorationshould be of superior quality.147,154–157

TEMPORARY CORONAL ACCESS FILLINGBalto et al.139 compared the leakage of differentprovisional materials used in post-prepared rootcanals. They found that none of the provisionalrestorations tested (Cavit, IRM, and Temp Bond)prevented coronal leakage when left for a long periodof time (30 days). Safavi et al.153 evaluated the prog-nosis of endodontically treated teeth followingdelayed placement of the definitive coronal restora-tion. A total of 464 endodontically treated teeth werefollowed radiographically. They found a higher suc-cess rate when the definitive restorations (silveramalgam, composite resin, or definitive restorationwith or without posts and cores) were placed ascompared with teeth restored with provisional cor-onal access restorations (IRM or Cavit).

Torabinejad et al.147 found that defective restora-tions could cause root canal system reinfectionwithin 19 days. Ray and Trope154 found that a com-bination of a poor coronal restoration and poorendodontic treatment resulted in a high failure rateof endodontically treated teeth. In a retrospectivestudy, Iqbal et al.155 found that a combination ofgood quality endodontic treatment and coronal

restoration leads to a high success rate of endodon-tically treated teeth. Contrasting results werereported by Tronstad et al.156 who found that thequality of the endodontic treatment was significantlymore important than that of the coronal restoration.

CONCLUSIONSFollowing endodontic treatment, post space prepara-tion should be performed and a post definitivelycemented as soon as possible: the same day for aprefabricated post, and as soon as possible for a cus-tom-fabricated post and core. The prepared toothshould then be restored with a well-fitting provisionalrestoration (good marginal seal and occlusion) fol-lowed by cementation of the definitive crown in asshort a time as possible.

Does the Use of a Cervical Ferrule

that Engages Tooth Structure Help

Prevent Tooth Fracture?

Survey data have been published that indicate thepercentage of respondents who felt a ferrule (circum-ferential band of metal) increased a tooth’s resistanceto fracture.43 Fifty-six percent of general dentists, 67%of prosthodontists, and 73% of board-certifiedprosthodontists felt that core ferrules increased atooth’s fracture resistance. To investigate this concept,several research studies have been performed. Some ofthe articles found ferrules are beneficial whereasothers found no increase in fracture resistance.

The results appear indecisive until differencesbetween study designs are analyzed. First, some ofthe studies tested ferrules that were part of a castmetal core (core ferrules),158–162 whereas other studiesevaluated the effectiveness of ferrules created by theoverlying crown engaging tooth structure.163–176 Onestudy evaluated both core ferrules and crown fer-rules.177 Second, there were differences in the formof the ferrule, and therefore, the manner by which themetal engaged tooth structure (beveled sloping sur-face versus extension over relatively parallel preparedtooth structure). Third, there were variations in theamount of tooth structure encompassed by the

1448 / Endodontics

ferrules. Table 7 permits a comparison of the studiesand the effectiveness of the various core and crownferrules.

The data generally indicate that ferrules formed aspart of the core are less effective than ferrules createdwhen the overlying crown engages tooth structure. Infour of the six core ferrule studies, they were found tobe ineffective.159,160,162,177 Also, in one of the twostudies where the core ferrule was effective, the ferruleform was a 2-mm parallel extension of the core overtooth structure as opposed to a bevel.158 In the otherstudy where core ferrules were found to be effective, atorsional force was used as opposed to an angularlingual force.161 In the crown ferrule studies, most ofthe ferrules effectively increased a tooth’s resistance tofracture. Only when the crown ferrule was of minimaldimension or had a sloping form, it was found to beineffective.163,177 In support of these studies, Rosenand Partida-Rivera178 found that a 2-mm cast goldcollar (not part of the post and core) was very effectivein preventing root fracture when a tapered screw postwas intentionally threaded into roots so as to induce

fracture. Assif et al.179 found no difference in the toothfracture patterns of parallel posts, tapered posts, andparallel posts with a tapered end when they werecovered by a crown that grasped 2 mm of toothstructure. Akkayan et al.170 found no significant dif-ference between fiber-reinforced and zirconia dowelswhen the ferrule length was 2 mm.

The data also support the concept that ferrules thatgrasp larger amounts of tooth structure are moreeffective than those engaging only a small amount oftooth structure. In both the core and crown ferrulestudies, the tooth’s resistance to fracture was increasedwhen a substantive amount of tooth structure wasengaged (2 mm in the core ferrule studies and 1 to2 mm in the crown ferrule studies). Libman andNicholls163 found the 0.5- to 1.0-mm crown ferruleto be ineffective whereas a 1.5- to 2.0-mm crownferrule to be effective. Isidor et al.165 determined thatincreasing the crown ferrule length significantlyincreased the number of cyclic cycles required to causespecimen failure. They compared no ferrule with 1.25and 2.55 mm crown ferrules. They concluded that

Table 7 Comparison of Studies and Effectiveness of Various Core and Crown Ferrules

Study Ferrule Form Was Ferrule Effective? Materials/Type of Test

Barkhordar (1989) 2 mm parallel extension

of core over the tooth

Yes Extracted teeth/angular lingual force

applied to p and c (no overlying crown)

Sorensen (1990) 1 mm wide 60� bevel at

the tooth-core junction

No Extracted teeth/angular lingual force applied to

p and c (with overlying crown)

Tjan (1985) 60� bevel at the tooth-core

junction

No Extracted teeth/angular lingual force applied to

p and c (no overlying crown)

Loney (1990) 1.5 mm parallel extension

of core over the tooth

No Photoelastic teeth/angular lingual force applied to

p and c (no overlying crown)

Hemmings (1991) 45� bevel Yes Extracted teeth/torsional force applied to p and c

(no overlying crown)

Saupe (1996) 2 mm parallel extension

of core over thin dentin

wall (0.5–0.75 mm thick)

No Extracted teeth/angular lingual force applied to

p and c (no overlying crown)

Sorensen (1990) 130� sloping finish line No Extracted teeth/p and c with crown

1–2 mm of tooth grasped by

crown

Yes Extracted teeth/p and c with crown

Libman (1995) 0.5–1 mm of prepared tooth

grasped by crown

No Extracted teeth/p and c with crown/cyclic loading

1.5–2 mm of prepared tooth

grasped by crown

Yes Extracted teeth/p and c with crown/cyclic loading

Milot (1992) 1 mm wide 60� bevel

grasped by crown

Yes Plastic analogues of teeth/p and c with crowns

Isidor (1999) 1.25 mm of prepared tooth

grasped by crown

Yes Bovine teeth/cyclic angular load/p and c

with crown

2.5 mm of prepared tooth

grasped by crown

Yes, but more effective than 1.25 mm Bovine teeth/cyclic angular load/p and c with

crown

Hoag (1982) 1–2 mm of prepared tooth

grasped by crown

Yes Extracted teeth/p and c with crown

Gegauff (2000) 2 mm of prepared tooth

grasped by crown; 0 mm of

prepared tooth grasped by a crown

Yes Composite teeth/p and c with crown

Chapter 40 / Restoration of Endodontically Treated Teeth / 1449

ferrule length was more important than post lengthin increasing a tooth’s resistance to fracture undercyclic loading. Zhi-Yue and Yu-Xing169 found that a2-mm crown ferrule effectively enhanced the fracturestrength of endodontically treated teeth when a castpost and core was used. Pereira et al.176 comparedthe effect of no crown ferrule with 1, 2, and 3-mmcrown ferrules. They found that a 3-mm crown fer-rule significantly increased the fracture resistance ofendodontically treated teeth compared with a 2-mmcrown ferrule.

The form of the prepared ferrule also appears toaffect a tooth’s fracture resistance in the previouslycited studies. Only one beveled/sloping ferrule waseffective in enhancing a tooth’s fracture resistanceand that was when a torsional force was applied tothe tooth. Tan et al.172 compared a 2-mm uniformcrown ferrule that extended around the entire crowncircumference with a 2-mm nonuniform crownferrule where the ferrule was only 0.5 mm on theproximal surfaces. The uniform ferrule produced sig-nificantly greater fracture resistance than a nonuni-form ferrule. In an in vitro study, Naumann et al.173

evaluated the effect of chewing simulation on thefracture resistance of maxillary endodontically treatedteeth with incomplete crown ferrules. The greatestvariation of failure load was associated with theabsence of portions (facial, palatal, or interproximal)of the crown ferrule. Ng et al.174 investigated the effectof limited residual axial tooth structure on the frac-ture resistance of maxillary anterior endodonticallytreated teeth. They found that in the absence of 360�

of circumferential coronal tooth structure, the loca-tion of the remaining coronal tooth structure may bean important factor for determining the fracture resis-tance of endodontically treated teeth. The palatal axialwall was as effective as a 360� circumference in pro-viding fracture resistance.

CONCLUSIONSDifferences of opinion exist regarding the effectivenessof ferrules in preventing tooth fracture. Ferrules havebeen tested when they are part of the core and alsowhen the ferrule is created by the overlying crownengaging tooth structure. Most of the data indicate thata ferrule created by the crown encompassing toothstructure is more effective than a ferrule that is partof the post and core (Figure 15). Ferrule effectiveness isenhanced by grasping larger amounts of tooth struc-ture. The amount of tooth structure engaged by theoverlying crown appears to be more important thanthe length of the post in increasing a tooth’s resistance

to fracture. Ferrules are more effective when the crownencompasses relatively parallel prepared tooth structurethan when it engages beveled/sloping tooth surfaces.Ferrules that encompass 2 mm of tooth structurearound the entire circumference of a tooth are moreeffective than nonuniform ferrules.

Post and Core Placement Techniques

PRETREATMENT DATA REVIEWWhen it has been determined that a post and core isrequired to properly retain a definitive single crownor fixed partial denture, the following characteristicsshould be determined prior to beginning the clinicalprocedures associated with the fabrication of a postand core.

POST LENGTHSince 5 mm of gutta-percha should be retained api-cally to ensure a favorable seal (as measured radio-graphically), posts should be extended to that lengthin all teeth except molars. With molars, posts shouldbe placed in the primary roots (palatal root of max-illary molars and distal roots of mandibular molars)and should not be extended more than 7 mm apical tothe origin of the root canal in the base of the pulpchamber (Figure 11). Extension beyond this lengthcan lead to root perforation or only very thin areasof remaining tooth structure.

Figure 15 Types of ferrules. A, Tooth prepared for a post and core.B, Post and core has been cemented into the tooth. The arrows notehow the core has created a ferrule around the tooth (note the reductionin the width of remaining coronal tooth structure to develop this coreferrule). C, A metal ceramic crown has been cemented over the core.The arrows show how the crown encompasses the tooth cervically,establishing a crown ferrule.

1450 / Endodontics

POST DIAMETERA frequently used and clinically appropriate guidelinefor post diameter is not to exceed one-third of theroot diameter. It has been determined that when aroot canal is prepared for a post and the diameter isincreased beyond one-third of the root diameter, thetooth becomes exponentially weaker. Each millimeterincrease (beyond one-third of the root diameter)causes a six-fold increase in the potential for rootfracture.62 Based on measuring the root dimensionsof 1,500 teeth (125 for each tooth) and using theguideline that the post should be one-third of the rootdiameter, optimal post diameter measurements havebeen determined to be approximately 0.6 mm formandibular incisors, 1.0 mm for maxillary centralincisors, maxillary and mandibular canines, and thepalatal root of the maxillary first molar.125 Therecommended post diameter for the other teeth was0.8 mm.125 Another study of 700 teeth recommendedthat post diameter should range from 0.7 mm formandibular incisors to a maximum of 1.7 mm formaxillary central incisors.102

ANATOMICAL/STRUCTURAL LIMITATIONSThe practitioner who completed the endodontic treat-ment is ideally suited to identify characteristics of thepulpal chamber, rooted canal(s) anatomy, and com-pleted endodontic filling that should be reviewedbefore placing a post and core. These characteristicsinclude the presence and the extent of dentinal crazelines, identification of teeth where further root pre-paration (beyond that needed to complete endodonticinstrumentation) will result in less than 1 mm ofremaining dentin or a post diameter greater thanone-third of the root diameter area, informationregarding areas where the remaining tooth structureis thin, and the point at which significant root curva-ture begins.

CRAZE LINESCracks in dentin are areas of weakness where furtherpropagation may result in root fracture and tooth loss(see Chapter 19). The patient should be informed oftheir presence with appropriate chart documentationof crack location. It is prudent to avoid post place-ment, if possible, in favor of a restorative materialcore. If a post is required, it should passively fit thecanal, and the definitive restoration should entirelyencompass the cracked area, whenever possible, byforming a ferrule.

DENTIN THICKNESS AFTER ENDODONTICTREATMENTFollowing normal and appropriate endodontic instru-mentation, teeth can possess less than 1 mm of dentin,indicating that there should be no further root pre-paration for the post. When these teeth are encoun-tered, it is best to fabricate a post that fits into theexisting morphological form and diameter rather thanadditionally preparing the root to accept a prefabri-cated type of post. This characteristic is one of theprimary indications for the use of a custom cast postand core. One study determined that canines (max-illary and mandibular), maxillary central and lateralincisors, and the palatal root of maxillary first molarspossessed more than 1 mm of dentin after endodonticcleaning and shaping.181 All other teeth had rootswith less than 1 mm of remaining dentin followingendodontic treatment. With the goal of preserving1 mm of remaining dentin lateral to posts, it has beendetermined that single-canal maxillary first premolarsshould have posts that are 0.7 mm in diameter orless.126 Mandibular premolars with oval/ribbon-shaped canals should not be subjected to any prepara-tion of the root canal for a post since it will result inless than 1 mm of dentin.181 Preparation of the mesialroot canals in mandibular molars and the facial rootcanals in maxillary molars can result in perforation oronly thin areas of remaining dentin. Based on themeasurements of residual dentin thickness, it isrecommended that posts not be placed in these rootsif possible.

ROOT CURVATUREWhen root curvature is present, post length must belimited so as to preserve remaining dentin, therebyhelping to prevent root fracture or perforation. Rootcurvature occurs most frequently in the apical 5 mmof the root. Therefore, if 5 mm of gutta-percha isretained apically, curved portions of the root areusually avoided. As discussed previously under postlength, molar posts should not exceed 7 mm in theroots because of the potential for perforation due toroot curvature and the presence of developmentalroot depressions. Molar roots are frequently curvedand the post should terminate at the point wheresubstantive curvature begins.

TYPE OF POST AND CORE

Custom Cast PostFor many years, custom cast posts and cores have beenconsidered to be the standard of care when restoring

Chapter 40 / Restoration of Endodontically Treated Teeth / 1451

endodontically treated teeth and have historically beenmade of metal. Gold, silver–palladium, and base metalalloys are the most commonly used metals. For eco-nomic reasons, base metal alloys were introduced as analternative metal to high-noble alloys. The major dis-advantages of base metal alloys are their manipulation(laboratory and clinical), their hardness, and theirunstable chemical structure.182 The degradation of basemetal alloys releases substances that could be harmful tothe patient.182–184 Silver–palladium alloys were intro-duced as a replacement for gold and base metal alloys.They are relatively easy to manipulate and have manyproperties similar to those of gold casting alloys.185

However, the castability of silver–palladium alloyswas shown to be inferior to that of gold-basedalloys.182,186,187

Cast posts and cores can be fabricated by usingeither a direct or an indirect technique, and severalmethods have been described for the intraoral fabri-cation of an acrylic resin pattern for a direct post andcore.188–192 Prefabricated plastic patterns are com-monly used, and they are relined to fit the post spacewith an autopolymerizing acrylic resin (Figure 16).The coronal adaptation of the tooth is usually com-pleted by using the same resin, and the core is con-toured intraorally to the desired form. The only dis-advantage of this direct technique is the amount ofchairside time required to perform the procedure.

As an alternative, indirect techniques for thefabrication of cast posts and cores have been pro-posed.193–195 However, this procedure requires meti-culous attention to a defined protocol to ensuresuccess. One technique uses a Lentulo spiral instru-ment to carry an impression material to the apicalaspect of the prepared post space. Since a thin projec-tion of a polymerized impression material can bedistorted or torn upon removal from the mouth,reinforcement of the impression material is required.This reinforcement can be accomplished by usingseveral materials such as a plastic pin or a metal wire.Care must be taken when using plastic pins to ensurethat they are not slightly flexed by placement into acurved canal or through contact with the impressiontray, thereby allowing a return to their original formupon impression removal with some resulting distor-tion. The use of a portion of a safety pin is an excel-lent material so long as it is made of spring steel,thereby preventing flexion. A bendable metal pincan be distorted upon impression removal. Completeseating of a section from a safety pin until it contactsthe gutta-percha is recommended. Upon removal ofthe impression from the mouth, the presence of themetal pin at the apical extension of the impression

material indicates that there was no elongation of theimpression material upon removal.

To make the impression technique easier, prefabri-cated precision plastic dowels were introduced.196,197

After the selection of the desired diameter for thedowel, a corresponding drill is used to prepare thepost space at the appropriate length. The dowel isthen inserted into the prepared canal, picked up inan impression, and transferred to the dental labora-tory for fabrication.

A proposed advantage of cast posts and cores istheir purported ease of removal in case of an endo-dontic retreatment.198–200 In addition, several long-term clinical studies have reported high success rateswith cast post and cores.50,201

Prefabricated PostsPrefabricated posts have become quite popular and awide variety of systems are available: parallel-sided ortapered, smooth or serrated, passive (cement/bonded)or active (threaded), or combinations of these.202–204

Threaded posts depend primarily on engaging thetooth—either through threads formed in the dentin as

Figure 16 Prefabricated plastic patterns commonly used for the directtechnique method for the intraoral fabrication of an acrylic resin patternfor a cast post and core.

1452 / Endodontics

the post is screwed into the root or through threadspreviously ‘‘tapped’’ into the dentin. The majority ofthese posts are metallic. Recently, in response to a needfor tooth-colored posts, several nonmetallic posts suchas carbon fiber epoxy resin, zirconia, glass fiber-reinforced (GFR) epoxy resin, and ultrahigh strengthpolyethylene fiber-reinforced (PFR) posts are availableand early data indicates that they can be acceptablealternatives to metallic posts.

The carbon fiber-reinforced (CFR) epoxy resinpost system was developed in France in 1988 by Duretand Renaud205–207 and first introduced in Europe inthe early 1990s.208–210 The matrix for this post is anepoxy resin reinforced with unidirectional carbonfibers parallel to the long axis of the post. The fibersare 8 mm in diameter and uniformly embedded in theepoxy resin matrix. By weight, the fibers comprise64% of the post and are stretched before injection ofthe resin matrix to maximize the physical propertiesof the post (Figure 17).205,211,212 The post is reportedto absorb applied stresses and distribute these stressesalong the entire post channel.213 The bulk of thecarbon fibers is made from polyacrylonitrile by heat-ing it in air at 200� to 250�C and then in an inertatmosphere at 1200�C. This process removes hydro-gen, nitrogen, and oxygen, leaving a chain of carbonatoms and forming carbon fibers.214

The CFR post has been reported to exhibit highfatigue strength, high tensile strength, and a modulusof elasticity similar to dentin.208,211,215–218 The postwas originally radiolucent; however, a radiopaque postis now available. Radiopacity is produced by placingtraces of barium sulfate and/or silicate inside the post.Mannocci et al.219 examined radiographically five dif-

ferent types of fiber posts. They found that only Com-posipost and Snowpostposts had uniform radiopacity.Finger et al.220 examined the radiopacity of seven fiber-reinforced resin posts compared with a titanium post.Compared to other posts, they found CFR posts had anacceptable radiopacity.

The posts are available in different shapes: doublecylindrical with conical stabilization ledges or conicalshapes (Figure 18). The surface texture of the postmay be smooth or serrated. Studies have indicatedthat serrations increased mechanical retentionalthough the smooth post also bonded well to adhe-sive dental resin.217,221 The post has a surface rough-ness of 5 to 10 mm to enhance mechanical adhesion ofthe autopolymerizing luting material, and the postappears to be biocompatible based on cytotoxicitytests.216,222

Several studies indicate that CFR posts exhibit ade-quate physical properties compared to metalposts.212,215,223,224 In a retrospective study over 4 years,Ferrari et al.223 indicated that the Cosmopost systemwas superior to the conventional cast post andcore system. King and Setchell215 and Duret et al.212

evaluated the physical properties (fracture resistanceand modulus of elasticity) of CFR posts and both

Figure 17 Surface texture of a carbon fiber-reinforced epoxy resindowel (SEM magnification: �1000).

Figure 18 Available shapes of carbon fiber-reinforced epoxy resinposts.

Chapter 40 / Restoration of Endodontically Treated Teeth / 1453

reported that these posts are stronger than prefabricatedmetal posts.

Contrasting results were reported by Sidoli et al.225

in an in vitro study. They found that CFR postsexhibited inferior strength when compared withmetallic posts. Similar results were also obtained byPurton and Love226 and Asmussen et al.227

Martinez-Insua et al.228 studied the fracture resis-tance of teeth restored with CFR posts and cast posts.They reported a significantly higher fracture thresholdfor cast post and cores. A clinical evaluation of CFRposts suggested that these posts did not perform as wellas conventional cast post and cores.229 However, theresults of this study must be interpreted with cautionbecause of the relatively small sample size (27 teeth)used in this study.

Multiple studies indicate that there is a decrease inthe strength of CFR posts after thermocycling andcyclic loading.230–233 In addition, contact of the postwith oral fluids reduced their flexural strengthvalues.222–234

In two studies, results indicated no significant dif-ference among a CFR post, cast post and cores, andmetal posts when restoring mandibular incisor teeth.No differences were noted in the mode or state offracture observed.235,236

Multiple in-vitro studies have reported that CFRposts are less likely to cause fracture of the root atfailure. The mode of failure of teeth restored withCFR posts in these studies was more favorable to theremaining tooth structure.170,215,225,228,237–241

However, despite all these advantageous properties,in vivo applications of the CFR post should be ques-tioned. When the ferrule is small or absent in anendodontically treated tooth restored with a CFPpost, loads may cause the post to flex causing amicromovement of the entire core. The cement sealat the margin of the crown can be compromised,accompanied by microleakage of oral bacteria andfluids. As a result, secondary caries may develop inthe space and may not be easily detected.241

The short-term clinical studies of CFR postsappear promising but some of the longer-term stu-dies report higher failure rates. Wennstrom209

restored 173 teeth with CFR posts and reportedtwo failures after a period of 3 to 4 years. A short-term retrospective study of 236 teeth treated 2 to 3years previously reported no failures of theposts.242 Ferrari et al.223 studied 100 CFR postsand reported a failure rate of 3.2% after a mean

time of 3.8 years of clinical service. In a prospectivestudy of 59 CFR posts, Glazer et al.243 indicatedthat these posts did not fracture and there was a7.7% absolute failure rate. Another retrospectivestudy244 of 1,304 CFR posts followed from 1 to 6years found a 3.2% failure rate that was attributedto debonding during removal of temporary crownsand periapical lesions. Hedlund et al.245 studied theclinical performance of 65 CFR posts for an averageof 2.3 years of clinical service and found a 3%failure rate. In a retrospective study of 64 CFRposts, Segerstrom et al.246 found that nearly 50%of the CFR posts were lost after a mean time of 6.7years.

Should fracture of a CFR post occur, a potentialadvantage is the relative ease of removal from the postspace compared with metal posts. A removal kit hasbeen suggested for this procedure and the latter isrecommended as a single use only item.247–251

Glass fiber-reinforced epoxy resin posts The highdemand for esthetic restorations and all-ceramiccrowns led to the development of a varity of tooth-colored post systems as an alternative to metal andCFR posts.

The GFR epoxy resin post is made of glass or silicafibers (white or translucent). Glass fiber posts can bemade of different types of glasses: electrical glass,high-strength glass, or quartz fibers (Figure 19).233,252

The commonly used fibers are silica-based (50% to70% SiO2), in addition to other oxides.253

Figure 19 Surface texture of a glass fiber-reinforced epoxy resin post(SEM magnification: �250).

1454 / Endodontics

The GFR post is available in different shapes: cylind-rical, cylindroconical, or conical shape (Figure 20). Anin vitro assessment of several GFR post systems indi-cated that parallel-sided GFR posts are more retentivethan tapered GFR posts.254

The composition of the glass fibers in the matrixtends to play an important role in the strength of thepost. Newman et al.232 compared the fracture resis-tance of two GFR posts containing different weightpercentages of glass fibers. They found that the highercontent of glass fibers in the post contributed to thegreater strength displayed by the tested post.

The GFR post has been reported to exhibit highfatigue strength, high tensile strength, and a modulusof elasticity closer to dentin than that of CFRposts.218,227,255 The GFR post is as strong as the CFRpost and approximately twice as rigid.256

The flexural strength of GFR posts is not related tothe type of glass fiber used. Galhano et al.218 evaluatedthe flexural strength of carbon fiber, quartz fiber, andglass fiber posts. They found that the posts behavedsimilarly because of the same concentration and typeof the epoxy resin used to join the fibers together.Pfeiffer et al.257 evaluated, in vitro, the yield strengthof GFR post, titanium, and zirconia posts. They foundthat the yield strength was significantly higher for thezirconia and titanium posts when compared with GFRposts.

Several studies have determined that there is adecrease in the strength (about 40%) of GFR postsafter thermocycling and cyclic loading. In addition,contact of the post with oral fluids (short- and long-term) reduced theird flexural strength.230,233,258–260

Two studies indicated that the tensile bond strengthbetween the composite resin core material and theGFR post is less than that developed with a titanium

post.261,262 Other studies indicated that there was agood adhesive bond between the GFR post and com-posite resin cements.261,263,264 The bonding of thecore to the post can be improved by treating the postwith airborne-particle abrasion.265 Similar resultswere obtained by treating the surface of the post withhydrogen peroxide and silane or hydrofluoric acidand silane.266,267 During fatigue loading, a compositeresin core bonded to a GFR post provided signifi-cantly stronger crown retention than cast gold postsand cores and titanium posts with composite resincores.171

Similar to CFR posts, multiple studies have shownthat GFR posts are less likely to cause fracture of theroot at failure.232,268–270 The mode of failure of teethrestored with CFR posts in these studies was morefavorable to the remaining tooth structure. However,studies have discussed the importance of the presenceof a ferrule effect in achieving a high successrate.170,173,174,271 Malferrari et al.270 restored 180 teethwith GFR posts and reported no post, core, or rootfracture after 30 months of service. Naumann et al.272

found that the survival rate of parallel-sided andtapered GFR posts was similar.

Polyethylene fiber-reinforced posts (PFR) are madeof ultrahigh molecular weight polyethylene-wovenfiber ribbon (Ribbond, Ribbond Inc., Seattle, WA).They are not posts and cores in the traditional sense.The post is a polyethylene-woven fiber ribbon that iscoated with a dentin bonding agent and packed intothe canal, where it is then light polymerized in posi-tion.273–275 The Ribbond material has a three-dimensional structure due to either a leno weave ora triaxial architectural design. These designs are com-posed of a great number of nodal intersections thatprevent crack propagation and provide a mechanicalretention for the composite resin cement. When PFRposts were compared with metal posts in the labora-tory, the fiber-reinforced posts reduced the incidenceof vertical root fracture. The addition of a small-sizeprefabricated post to the PFR post increased thestrength of the post-and-core complex. However, thestrength of the PFR post did not approach that of acast metal post and core.273

When compared with other fiber-reinforced com-posite post systems, the PFR posts were also found toprotect the remaining tooth structure.232 These resultsmay be attributed to the manufacturer’s recommen-dations of not enlarging the root canals, not removingundercuts present in the root canal, and forming a 1.5to 2mm crown ferrule. The presence of a large volumeof core material and a sufficient dentin bonding areacoronally seems to greatly affect the mean load-to-failure

Figure 20 Available shapes and designs for glass fiber-reinforced epoxyresin posts.

Chapter 40 / Restoration of Endodontically Treated Teeth / 1455

value of PFR posts.232 Eskitascioglu et al.276 evalu-ated two post and core systems using a fracturestrength test and a finite element analysis. Theyfound that stress accumulated along the cervicalregion of the tooth and along the buccal bone.Minimal stress was recorded within the PFR postsystem. They suggested that the PFR post could beadvantageous for the restoration of teeth with apicalresection.

Newman et al.232 compared the effect of threefiber-reinforced composite post systems on the frac-ture resistance of endodontically treated teeth. Theyfound that when PFR posts were placed in narrowcanals, they performed better than GFR posts. Theysuggested the PFR post be formed to the shape of thecanal.

The use of PFR posts to restore endodonticallytreated teeth appears to be a promising alternative tothe stainless steel and zirconia dowel posts withrespect to microleakage.277 Usumez et al.277 comparedin vitro the microleakage of three esthetic, adhesivelyluted post systems with a conventional post system.They found that the PFR posts and the GFR postsexhibited less microleakage compared with zirconiaposts.

Zirconia posts The trend toward the use of all-ceramiccrowns has encouraged manufacturers to explore thedevelopment of all-ceramic posts.278–281 A metal-freepost avoids discoloration of tooth structure that canoccur with metal posts and produces optical propertiescomparable to all-ceramic crowns.282–285 One type ofall-ceramic post is the zirconia post, composed of zir-conium oxide (ZrO2), an inert material used for a rangeof applications. Its high fracture toughness, high flexuralstrength, and excellent resistance to corrosion encour-aged orthopedists to use it at articulation surfaces.286

Studies have suggested that zirconia specimens trans-planted in animals were very stable after long-termaging, and there was no apparent degradation of thespecimens.286,287–290

Zirconia (tetragonal zirconium polycrystals, TZP)exhibits phase transformation. Low-temperaturedegradation of TZP is known to occur as a result ofspontaneous phase transformation of tetragonal zir-conia to monoclinic phase during ageing at 130� to300�C possibly within a water environment. It hasbeen reported that this degradation leads to a decreasein strength due to the formation of microcracksaccompanying the phase transformation. To inhibitthis phase transformation, certain oxides (magne-sium, yttrium, or calcium oxide) are added to fullyor partially stabilize the tetragonal phase of zirconia at

room temperature. This mechanism is known astransformation toughening.281,287,291–293

The type of zirconia used for dental posts is com-posed of TZP with 3 mol% yttrium oxide (Y2O3) andis called YTZP (yttria-stabilized tetragonal polycrys-talline zirconia).281,294 YTZP is composed of a densefine-grained structure (0.5 mm average diameter) thatprovides the post with toughness and a smooth sur-face.292,294,295

The zirconia post is extremely radiopaque, biocom-patible, possesses high flexural strength and fracturetoughness, and may act similar to steel.287–291,296–304

In addition, the post has a low solubility301 and is notaffected by thermocycling.230 The post is available in acylindroconical shape (Figure 21).

The zirconia post has a smooth surface configura-tion with no grooves, serrations, or roughness to

Figure 21 Available shapes and designs for zirconia posts.

1456 / Endodontics

enhance mechanical retention (Figure 22). As a result,the zirconia post does not bond well to compositeresins and may not provide the best support for abrittle all-ceramic crown.261,305–308 Dietschi et al.307

found that these posts also have poor resin-bondingcapabilities to dentin after dynamic loading and ther-mocycling due to the rigidity of the post. In a cyclicloading test performed in a wet environment, Man-nocci et al.239 found that the survival rate of zirconiaposts compared with fiber posts was significantlylower.

In vitro studies261,264,308,309 indicated that the smoothsurface configuration of untreated zirconia posts leadsto failure at the cement/post interface. The vast majorityof the cement remained in the root and was notattached to the zirconia posts. Wegner and Kern310

evaluated the bond strength of composite resin cementto zirconia posts. They found that the long-term bondstrength of the resin composite cement to zirconia postsis weak. Several studies found that acid etching andsilanization of zirconia posts does not improve thestrength of the resin bond to the zirconia-based materialbecause of the lack of or no silica content in thepost.310–313 However, tribochemical silica coating wasfound to increase the bond strength of the compositeresin to the zirconia post.314,315 Oblak et al.316 com-pared the fracture resistance of prefabricated zirconia

posts after different surface treatments. They found thatairborne particle-abraded posts exhibited significantlyhigher resistance to fracture than posts that have beenground with a diamond instrument.

The use of heat-pressed glass to form the coreinstead of composite resin has been suggested.201,299,300

This approach may improve the physical properties ofthe all-ceramic post and core.

When the mechanical properties of zirconia postswere evaluated, it was reported that these posts arevery stiff and strong, with no plastic behavior.227,298,299

Pfeiffer et al.257 found that the zirconia post had asignificantly higher yield strength compared with tita-nium and GFR posts.

Several studies indicated that many commonly usedposts exhibit higher fracture resistance than zirconiaposts.238,297,317,318 In addition, once they fracture the,irretrievable posts will leave unrestorable roots.170,318

Nothdurft et al.319 evaluated the clinical perfor-mance of 30 zirconia posts in a short-term retrospec-tive study. They found no signs of failure of theseposts. However, these results should be analyzed withcaution because of the small sample size and a shortfollow-up time.

Root Selection for Multirooted Teeth

PREMOLARSWhen posts and cores are needed in premolars, postsare best placed in the palatal root of the maxillarypremolar and the straightest root of the mandibularpremolar. The buccal root could be prepared to adepth of 1 to 2 mm and to serve as an antirotationallock, if needed.

MOLARSWhen posts and cores are needed in molars, posts arebest placed in roots that have the greatest dentinthickness and the smallest developmental root depres-sions. The most appropriate roots (the primary roots)in maxillary molars are the palatal roots and in

Figure 22 Surface texture of zirconia post (SEM magnification: �1000).

Chapter 40 / Restoration of Endodontically Treated Teeth / 1457

mandibular molars are the distal roots (Figure 23).The facial roots of maxillary molars and the mesialroot of mandibular molars should be avoided if at allpossible. If these roots must be used in addition to theprimary roots, then the post length should be short (3to 4 mm) and a small-diameter instrument should beused (no larger than a No. 2 Peeso instrument that is1.0 mm in diameter). When 7-mm long posts wereplaced in the mesial root of mandibular molars, 20 ofthe 75 tested teeth had only a thin layer of remainingdentin or were perforated.90

Type of Definitive Restoration

It is important to know the type of single crown orretainer (all-metal, all-ceramic, metal ceramic) thatwill be used as the definitive restoration for eachendodontically treated tooth that requires a post andcore. This knowledge permits the tooth to be reducedin accordance with the reduction depths and formrecommended for each type of crown/retainer.

CORONAL TOOTH PREPARATIONRestoration of endodontically treated teeth must be ateam effort between the endodontist and the dentistresponsible for the coronal restoration, requiring two-way communication. If it can be co-coordinated, thefirst step in the fabrication of a post and core shouldideally be preparation of the coronal tooth structure(Figure 24) for the type of definitive restoration thatwill be placed (all-metal crown, metal ceramic crown,all-ceramic crown). This procedure will help in deter-mining the structure of the post–core fabrication.Each type of restoration requires different amountsof tooth reduction, and the form of the tooth pre-paration varies considerably. By preparing the coronaltooth structure first, the structural integrity ofremaining dentin and enamel can be assessed. Whenthe remaining peripheral tooth structure is very thinand would likely not possess sufficient strength toresist occlusal forces transmitted through the crownto the tooth, the thin structure is removed andreplaced as part of the core. This order of procedurealso establishes morphological borders that can beused to guide core fabrication so that it is confluentwith the surrounding tooth structure and possessesthe desired tooth preparation form.

PULPAL CHAMBER PREPARATIONTreatment materials present in the pulpal chamberfollowing endodontic treatment (restorative materials

Figure 23 Placement of ParaPost and restorative material core in amolar. A, Endodontic treatment completed. B, Provisional restorativematerial in the pulpal chamber has been removed and gutta-percharemoved from the distal root canal. C, Post space formed with a drill.D, Trial placement of the post. E, The post has been shortened andcemented. A restorative material core has been formed. F, The toothwith core has been prepared, an impression made, and the definitivecrown cemented. G, If there is an extended time delay between place-ment of the core and preparation of the tooth for a crown, the core canbe built to full tooth contour to serve as the interim restoration.

Figure 24 Coronal tooth preparation. The existing crown has beenremoved on an endodontically treated tooth. Initial reduction of thetooth has been completed to permit assessment of integrity of remainingcoronal tooth structure.

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sealing the coronal access and gutta-percha) areremoved by using rotary instruments (Figure 25). Ifa prefabricated post is cemented into a root canal anda restorative material core built around the post,morphological undercuts present in the pulpal cham-ber should be retained for core retention. If a customcast post and core is fabricated, then pulpal chamberundercuts must be either blocked out with a definitivecement or a restorative material that is bonded to thetooth or the undercut eliminated by removing thetooth structure. If removing the undercut throughtooth preparation would result in substantive toothstructure removal that weakens the tooth, then block-ing out the undercut is the treatment of choice.

ROOT CANAL PREPARATIONThe individual who completed the root canal is ideallysuited to prepare the root canal, being the one that ismost knowledgeable regarding root curvatures andareas where no further root preparation shouldbe performed because it will result in areas of thin

residual dentin. For this reason, it may be prudent toprepare the root canal for a post as a continuation ofthe endodontic treatment.

If the canal has not been prepared for a post as partof the endodontic treatment process, it is necessary toremove the filling material using either a warm endo-dontic hand instrument or a slow-speed rotaryinstrument such as a Gates Glidden drill (DentsplyInternational, Tulsa, OK) or a Peeso instrument(Dentsply International). If a warm hand instrumentis used, it is advisable to place a rubber dam so as toprevent aspiration or swallowing of the hand instru-ment should it be dropped.

Successful use of rotary instruments is related toinitially using a small-diameter instrument (one thatremoves only the filling material without dentinremoval). This small-diameter instrument is used toremove small vertical increments (1 to 2 mm) of theroot canal filling material. After each vertical incre-ment is removed, a visual inspection should be madeto verify that the endodontic filling material is cen-tered in the post preparation. The incremental rootcanal filling removal is continued until the appro-priate length is established (Figure 26). Post prepara-tion length is determined using a periodontal probe.Remaining gutta-percha length is evaluated by com-paring periodontal probing depths with landmarkson the postendodontic radiograph and by making aradiograph of the prepared post space. After thelength is established, any required increases to thepost diameter are performed using incrementallylarger rotary instruments or hand files.

Preparation for Overdentures

‘‘The overdenture is a complete denture supported byretained teeth and the residual alveolar ridge.’’320

Because the ‘‘retained teeth’’ are shortened, contoured,

Figure 25 Pulp chamber preparation. Rotary instrument being used toremove provisional material.

A B C

Figure 26 Root canal preparation. A, Rotary instrument being used to prepare post space in the root canal. Note the rubber ring around the instrumentto identify the appropriate apical extension of the post preparation. B, Periodontal probe being used to measure post space depth. C, Post spacepreparation completed.

Chapter 40 / Restoration of Endodontically Treated Teeth / 1459

and altered to be covered, root canal therapy isalmost always required. In 1969, Lord and Teel321

coined the term ‘‘overdenture’’ and described the com-bined endodontic–periodontic–prosthodontic techni-que applied thereto. As early as 1916, however, Protherohad referred to the use of root support, stating, ‘‘Often-times two or three widely separated roots or teeth can beutilized for supporting a denture.’’322 It should also benoted that much earlier, in 1789, George Washington’sfirst lower denture, constructed of ivory by John Green-wood, retained a mandibular left premolar.323

Retaining roots in the alveolar process is based onthe proven observation that so long as the rootremains, the bone surrounding it remains (Figure 27).This overcomes the age-old prosthetic problem ofridge resorption. Ideally, then, retaining four teeth,two molars, and two canines, one each at the fourdivergent points of an arch, should ensure prosthesisbalance and long ‘‘life’’ to a complete overdenture(Figure 28). Unfortunately, patients requiring pros-theses seldom present just these ideal conditions.Decisions regarding which teeth to retain usuallyfocus on keeping some of the healthiest teeth locatedin strategic positions such as canines. One situation tobe warned against, however, is the diagonal cross-archarrangements, a molar abutment on one side, forexample, and a canine on the opposite side. The rock-ing and torquing action set up by this arrangementoften leads to problems and loss of one or both abut-ments. The molar abutment alone is preferable to thediagonal cross-arch situation.

If the selected abutment tooth is reduced to a shortrounded or bullet-shaped structure and literally ‘‘tuck-ing’’ the abutments inside the denture base, thecrown–root ratio of the tooth is vastly improved, espe-cially when periodontally involved teeth have lost somealveolar support. As a shortened tooth, however, it willserve admirably as an abutment for an overdenture.

INDICATIONS AND ADVANTAGESThe indications for overdentures include the psychicsupport some patients receive from not being totallyedentulous. Even more important are the preservationof the alveolar ridge and the shielding of the ridgefrom stress provided by firm abutment teeth. Itshould also be noted that occlusal vertical dimensionis better preserved if ridge height is maintained. Abonus to all these advantages is the support, thestability, and retention derived from abutments. Allthese advantages are heightened in the young patientwho must wear dentures for years to come.

Complete overdentures should be considered forvirtually every patient for whom complete mouthextractions are being considered. Sometimes, certainteeth can be periodontally and endodontically treatedand retained as abutments to support an overdenture.The overdenture better resists occlusal forces than thetotally tissue-supported complete denture. Some attri-bute this resistance to the proprioceptive sensorymechanism derived from the retained roots underthe overdenture. Application of the overdenture toremovable partial denture support is also indicated,even if only one abutment is available.

CONTRAINDICATIONSThe overdenture technique is contraindicated whenremaining alveolar support is so lacking that no toothcan be retained for very long. This condition oftensupports the use of endosseous root-form implants tosupport and retain a prosthesis. Overdentures are alsocontraindicated if the remaining natural teeth areadequate to restore the mouth with fixed partial

Figure 27 Dramatic demonstration of alveolar bone remaining aroundretained canines but badly resorbed under complete maxillary andposterior mandibular removable partial dentures.

Figure 28 Mirror view of four retained abutments providing idealsupport for an overdenture. Note the properly contoured and polishedcopings protecting the abutment teeth.

1460 / Endodontics

dentures or removable partial dentures. The overden-ture technique should be no pathway to expediency.

ABUTMENT TOOTH SELECTION‘‘A healthy abutment tooth for an overdenture musthave minimal mobility, a manageable sulcus depth,and an adequate band of attached gingiva.’’320 If theseprerequisites are lacking, the pocket depth can bereduced and attached gingiva developed by usingappropriate periodontal procedures.

ABUTMENT TOOTH LOCATIONIdeal teeth to retain are those whose occlusal forceswreak greatest destruction upon the ridges. Opposite anatural dentition, the canine teeth are ideal to retain.In edentulous patients, the anterior portion of thearches is particularly susceptible to resorption, socanines and premolars are again the first choice to be

saved, with incisors the second choice. It is especiallyimportant to save mandibular teeth because of diffi-culties encountered in retaining mandibular dentures.Even saving a single tooth, a molar in particular, maycontribute greatly to long-term denture success.

TECHNIQUEAfter the selection of the most favorable abutmentteeth, the key to successful overdenture fabrication issimplicity of technique (Figure 29). If an immediatedenture is to be placed, the endodontic therapy,extractions, and periodontal treatment can some-times be done at the denture placement appoint-ment. The crowns of these teeth are amputated 3to 4 mm above the gingival level and the endodonticprocedure completed. The coronal 5 to 6 mm of thegutta-percha restoration is removed, the preparationis undercut, and a well-condensed amalgam filling isplaced to restore and help seal the canal obturation.

A

C

B

DE

Figure 29 Preparing an overdenture abutment. A, The crown is amputated 3 to 4 mm above the gingival level. B, The endodontic procedure is started.C and D, An amalgam restoration is placed in the coronal 5 to 6 mm. E, In preparation for fitting the prosthesis, the abutments are shaped and polished.

Chapter 40 / Restoration of Endodontically Treated Teeth / 1461

At this time as well, the abutments should be shapedto rise 2 to 3 mm above the tissue, and be roundedor bullet-shaped with a slope back from the labial toaccommodate the denture tooth to be set above it.They should then be highly polished. The abutmentsmust not be too short or the tissue will grow overthem as a ‘‘lawn grows over a sidewalk’’;320 norshould they be too long, compromising the denturecontour and placing greater stress on the supportingteeth (Figure 30).

The denture is relieved over the abutments andadaptation is achieved between the denture base andedentulous ridge tissues without touching the abut-ment teeth. It is then adapted to the abutment teethby using a small amount of autopolymerizing acrylicresin (Figure 31). This proper relationship of dentureto tissue and tooth is important for denture stabilityand to keep the stresses on the teeth within physiolo-gical limits.

Some overdenture abutment teeth may not needroot canal therapy because they are so abraded thatthe pulp has receded to a level where the toothonly needs shortening, contouring, and polishing(Figure 32). This technique simplifies the treatmentand reduces the cost to the patient.

Figure 30 Improperly contoured overdenture abutments. Square edgesinvite grip by overdenture and torquing action. Prominent buccal contourand extra height comprise the contour of the overdenture. Courtesy ofDr. David H. Wands.

Figure 31 Soft, autopolymerizing acrylic resin fills the depression pre-pared in the denture to receive the abutment. This may be replacedwhenever necessary.

Figure 32 A, Teeth with vital, receded pulps but severe abrasion can be ideal overdenture abutments. B, Incisor overdenture abutment not requiringtherapy owing to pulp recession. The calcified pulpal area should be carefully explored. Courtesy of Dr. David H. Wands.

1462 / Endodontics

If the abutment teeth are periodontally involved orare not surrounded by a good collar of attachedgingiva, periodontal therapy will be required to cor-rect these aberrations.

PROBLEMSA number of problems have arisen with overdentures,most of them related to poor patient selection and lackof patient cooperation. The most serious problems areassociated with dental caries and periodontal disease.It must be remembered that throughout their lives,candidates for complete dentures are those who haveusually been neglectful of their teeth and supportingstructures and have a history of extensive dental dis-ease (Figure 33). In recommending overdentures,there is some risk. The patients’ habits must changeand they must become motivated and adept at oralhygiene to retain the vestiges of their dentition. Thatsome do not, should come as no surprise (Figure 34).The importance of good home care must be empha-sized to the overdenture patient and is a critical factorin long-term success. In a longitudinal study, Ettingerand Qian324,325 evaluated the differences in peoplewho experienced postprocedural problems with over-dentures and compared them with people who had noproblems for the duration of the study. They foundthat most of the failures could have been prevented bybetter oral hygiene. The most common problem wasthe development of periradicular problems aroundendodontically treated teeth because of recurrent car-ies causing the loss of the restoration sealing the root

canal. Other challenges related to the use of endodon-tically treated teeth included wear of the dentin andthe need for auxiliary prosthesis retention.

POSSIBLE SOLUTIONS TO THE PROBLEMSQuite naturally the prime solution to the caries–periodontal problem is better patient cooperation inhome care. Fluoride gels should regularly be placed inthe ‘‘well’’ of the dentin base where the abutments arelocated to remineralize the dentin.326,327 This, of

Figure 33 Rather typical neglect by many denture patients. A, Caries and periodontal disease forecast probable lack of future patient cooperation.B, Mirror view of lingual gingiva of two possible overdenture abutments. Because it is virtually impossible to develop attached gingiva in the lingualarea, the use of these teeth as abutments is contraindicated. Courtesy of Dr. David H. Wands.

Figure 34 Two-year recall reveals advanced caries and periodontaldisease of abutments. The patient did not remove the denture for daysat a time. Courtesy of Dr. David H. Wands.

Chapter 40 / Restoration of Endodontically Treated Teeth / 1463

course, will do nothing for periodontal disease, whichcan only be controlled by plaque removal and byproper and equal force placed on the abutments.More frequent denture relines may also be required.

Coverage of the dentinal surfaces is recommendedfor those situations where wear of the contactingdentinal surfaces is noticed. Bruxism is a principaletiological factor in producing wear. Even gold cast-ings placed over the teeth may eventually be wornthrough, but it takes a much longer time.328

A possible solution to inadequate denture retentionor to the rotational problem centering around a singleanterior abutment tooth involves the use of mechan-ical attachments. There are a number of attachmentson the market and they include ball and socket type ofattachments, o-rings and magnets, frequently retainedin the root through the use of a post (Figure 35).

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255. Bae JM, Kim KN, Hattori M, et al. The flexural properties offiber-reinforced composite with light-polymerized polymermatrix. Int J Prosthodont 2001;14:33–9.

256. Triolo PT, Trajtenberg C, Powers JM. Flexural propertiesand bond strength of an esthetic post. [abstract 3538] J DentRes 1999;78:548.

257. Pfeiffer P, Schulz A, Nergiz I, Schmage P. Yield strength ofzirconia and glass fibre-reinforced posts. J Oral Rehabil2006;33:70–4.

258. Vallittu P. Effect of 180-week water storage on the flexuralproperties of E-glass and silica fiber acrylic resin composite.Int J Prosthodont 2000;13:334–9.

259. Lassila LVJ, Nohrstrom T, Vallitu P. The influence of short-term water storage on the flexural properties of unidirec-tional glass fiber-reinforced composites. Biomaterials2002;23:2221–9.

260. Grant T, Bradley W. In-situ observations in SEM of degra-dation of graphite/epoxy composite materials due to sea-water immersion. J Compos Mater 1995;29:852–67.

261. Al-harbi F, Nathanson D. In vitro assessment of retention offour esthetic dowels to resin core foundation and teeth. JProsthet Dent 2003;90:547–55.

262. Coelho Santos G Jr, El-Mowafy O, Henrique Rubo J. Dia-metral tensile strength of a resin composite core with non-metallic prefabricated posts: an in vitro study. J ProsthetDent 2004;91:335–41.

263. Le Bell AM, Lassila LVJ, Kangasniemi I, Vallittu PK. Bond-ing of fibre-reinforced composite post to root canal dentin. JDent 2005;33:533–9.

264. Hedlund SO, Johansson NG, Sjogren G. Retention of pre-fabricated and individually cast root canal posts in vitro. BrDent J 2003;195:155–8.

265. Balbosh A, Kern M. Effect of surface treatment on retention ofglass-fiber endodontic posts. J Prosthet Dent 2006;95:218–23.

266. Vano M, Goracci C, Monticelli F, et al. The adhesionbetween fibre posts and composite resin core: the evaluationof microtensile bond strength following various surface che-mical treatments to posts. Int Endod J 2006;39:31–9.

267. Monticelli F, Toledano M, Tay FR, et al. Post-surface con-ditioning improves interfacial adhesion in post/core restora-tions. Dent Mater 2006;22:602–9.

268. Stricker EJ, Gohring TN. Influence of different posts andcores on marginal adaptation, fracture resistance, and frac-ture mode of composite resin crowns on human mandibularpremolars. An in vitro study. J Dent 2006;34:326–35.

269. Hu S, Osada T, Shimizu T, et al. Resistance to cyclic fatigueand fracture of structurally compromised root restored withdifferent post and core restorations. Dent Mater J2005;24:225–31.

270. Malferrari S, Monaco C, Scotti R. Clinical evaluation of teethrestored with quartz fiber-reinforced epoxy resin posts. Int JProsthodont 2003;16:39–44.

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271. Naumann M, Preuss A, Frankenberger R. Reinforcementeffect of adhesively luted fiber reinforced composite versustitanium posts. Dent Mater 2007; 23 (2):138–44.

272. Naumann M, Blankenstein F, Dietrich T. Survival of glassfiber reinforced composite post restorations after 2 years—an observational clinical study. J Dent 2005;33:305–12.

273. Sirimai S, Riis DN, Morgano SM. An in vitro study of thefracture resistance and the incidence of vertical root fractureof pulpless teeth restored with six post-and-core systems. JProsthet Dent 1999;81:262–9.

274. Deliperi S, Bardwell DN, Coiana C. Reconstruction of devi-tal teeth using direct fiber-reinforced composite resins: acase report. J Adhes Dent 2005;7:165–71.

275. Eskitascioglu G, Belli S. The use of bondable reinforcementfiber for post-and-core buildup in an endodontically treatedtooth: a case report. Quintessence Int 2002;33:549–51.

276. Eskitascioglu G, Belli S, Kalkan M. Evaluation of two postcore systems using two different methods (fracture strengthtest and a finite element analysis). J Endod 2002;28:629–33.

277. Usumez A, Cobankara FK, Ozturk N, et al. Microleakage ofendodontically treated teeth with different dowel systems. JProsthet Dent 2004;92:163–9.

278. Meyenberg KH, Luthy H, Scharer P. Zirconia posts: a newall-ceramic concept for non-vital abutment teeth. J EsthetDent 1995;7:73–80.

279. Zalkind M, Hochman N. Esthetic considerations in restoringendodontically treated teeth with posts and cores. J ProsthetDent 1998;79:702–5.

280. Zalkind M, Hochman N. Direct core buildup using a pre-formed crown and prefabricated zirconium oxide post. JProsthet Dent 1998;80:730–2.

281. Ahmad I. Yttrium-partially stabilized zirconium dioxideposts: an approach to restoring coronally compromisedteeth. Int J Periodont Restor Dent 1998;18:454–65.

282. Sorensen JA, Mito WT. Rationale and clinical technique foresthetic restoration of endodontically treated teeth withCosmopost and IPS Empress post system. QDT 1998;81–90.

283. Michalakis KX, Hirayama H, Sfolkos J, Sfolkos K. Light trans-mission of posts and cores used for the anterior esthetic region.Int J Periodont Restor Dent 2004;24:462–9.

284. Carossa S, Lombardo S, Pera P, et al. Influence of posts andcores on light transmission through different all-ceramiccrowns: spectrophotometric and clinical evaluation. Int JProsthodont 2001;14:9–14.

285. Ottl P, Hahn L, Lauer HCh, Fay M. Fracture characteristicsof carbon fibre, ceramic and non-palladium endodontic postsystems at monotonously increasing loads. J Oral Rehabil2002 Feb;29(2):175–83.

286. Cales B, Stefani Y, Lilley E. Long-term in vivo and in vitroaging of a zirconia ceramic used in orthopaedy. J BiomedMater Res 1994;28:619–24.

287. Christel P, Meunier A, Heller M, et al. Mechanical propertiesand short-term in vivo evaluation of yttrium-oxide-par-tially-stabilized zirconia. J Biomed Mater Res 1989;23:45–61.

288. Ichikawa Y, Akagawa Y, Nikai H, Tsuru H. Tissue compat-ibility and stability of a new zirconia ceramic in vivo. JProsthet Dent 1992;68:322–6.

289. Purton DG, Love RM, Chandler NP. Rigidity and retentionof ceramic root canal posts. Oper Dent 2000;25:223–7.

290. Drouin JM, Cales B, Chevalier J, Fantozzi G. Fatigue beha-vior of zirconia hip joint heads: experimental results andfinite element analysis. J Biomed Mater Res 1997;34:149–55.

291. Porter DL, Heuer AH. Mechanism of toughening partiallystabilized zirconia ceramics (PSZ). J Am Ceram Soc1977;60:183–4.

292. Gubta TK, Lange FF, Bechtold JH. Effect of stress-inducedphase transformation on the metastable tetragonal phase. JMater Sci 1978;13:1464–70.

293. Guazzato M, Albakry M, Ringer SP, Swain MV. Strength,fracture toughness and microstructure of a selection of all-ceramic materials. Part II. Zirconia-based dental ceramics.Dent Mater 2004;20:449–56.

294. Schweiger M, Frank M, Rheinburger V, Holand W. Newsintered glass-ceramics based on apatite and zirconia endoss-eous implant in initial bone healing. J Prosthet Dent1993;69:599–604.

295. Hulbert TK, Lange FF, Bechtold JH. Effect of stress-inducedphase transformation on the metastable tetragonal phase. JMater Sci 1978;13:1464–70.

296. Soares CJ, Mitsui FH, Neto FH, et al. Radiodensity evalua-tion of seven root post systems. Am J Dent 2005Feb;18(1):57–60.

297. Rosentritt M, Furer C, Behr M, et al. Comparison of in vitrofracture strength of metallic and tooth-coloured posts andcores. J Oral Rehabil 2000;27:595–601.

298. Taira M, Nomura Y, Wakasa K, et al. Studies on fracturetoughness of dental ceramics. J Oral Rehabil 1990;17:551–63.

299. Hochman N, Zalkind M. New all-ceramic indirect post-and-core system. J Prosthet Dent 1999;81:625–9.

300. Dilmener FT, Sipahi C, Dalkiz M. Resistance of three newesthetic post-and-core systems to compressive loading. JProsthet Dent 2006;95:130–6.

301. Piconi C, Maccauro G. Zirconia as a ceramic biomaterial.Biomaterials 1999;20:1–25.

302. Kakehashi Y, Luthy H, Naef R, et al. A new all-ceramic postand core system: clinical, technical, and in vitro results. Int JPeriodont Restor Dent 1998;18:586–93.

303. Koutayas SO, Kern M. All-ceramic posts and cores: the stateof the art. Quintessence Int 1999;30:383–92.

304. Heydecke G, Butz F, Hussein A, Strub JR. Fracture strengthafter dynamic loading of endodontically treated teeth

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restored with different post-and-core systems. J ProsthetDent 2002;87:438–45.

305. Perdigao J, Geraldeli S, Lee IK. Push-out bond strength oftooth-colored posts bonded with different adhesive systems.Am J Dent 2004;17:422–6.

306. Cohen BI, Pagnillo MK, Newman I, et al. Retention of corematerial supported by three post head designs. J ProsthetDent 2000;83:624–8.

307. Dietschi D, Romelli M, Goretti A. Adaptation of adhesiveposts and cores to dentin after fatigue testing. Int J Prostho-dont 1997;10:498–507.

308. Baba NZ. The effect of eugenol and non-eugenol endodonticsealers on the retention of three prefabricated posts cemen-ted with a resin composite cement [thesis]. Boston, MA:Boston University; 2000.

309. Gernhardt CR, Bekes K, Schaller HG. Short-term retentivevalues of zirconium oxide posts cemented with glass iono-mer and resin cement: an in vitro study and a case report.Quintessence Int 2005;36:593–601.

310. Wegner SM, Kern M. Long-term resin bond strength tozirconia ceramic. J Adhes Dent 2000;2:139–47.

311. Madani M, Chu FCS, McDonald AV, Smales RJ. Effects ofsurface treatments on shear bond strengths between a resincement and an alumina core. J Prosthet Dent 2000;83:644–7.

312. Blixt M, Adamczak E, Linden L, et al. Bonding to denselysintered alumina surfaces: effect of sandblasting and silicacoating on shear bond strength of luting cements. Int JProsthodont 2000;13:221–6.

313. Ozcan M, Alkumru HN, Gemalmaz D. The effect of thesurface treatment on the shear bond strength of lutingcement to glass-infiltrated alumina ceramic. Int J Prostho-dont 2001;14:335–9.

314. Matinlinna JP, Lassila LV, Ozcan M, et al. An introductionto silanes and their clinical applications in dentistry. Int JProsthodont 2004;17:155–64.

315. Xible AA, de Jesus Tavares RR, de Araujo Cdos R, BonachelaWC. Effect of silica coating and silanization on flexural and

composite-resin bond strength of zirconia posts: an in vitrostudy. J Prosthet Dent 2006;95:224–9.

316. Oblak C, Jevnikar P, Kosmac T, et al. Fracture resistance andreliability of new zirconia posts. J Prosthet Dent2004;91:342–8.

317. Mitsui FH, Marchi GM, Pimenta LA, Ferraresi PM. In vitrostudy of fracture resistance of bovine roots using differentintraradicular post systems. Quintessence Int 2004;35:612–16.

318. Akkayan B, Gulmez T. Resistance to fracture of endodonti-cally treated teeth restored with different post systems. JProsthet Dent 2002;87:431–7.

319. Nothdurft FP, Pospiech PR. Clinical evaluation of pulplessteeth restored with conventionally cemented zirconia posts:a pilot study. J Prosthet Dent 2006;95:311–14.

320. Lord JL, Teel S. The overdenture: Patient selection, use ofcopings, and follow-up evaluation. J Prosthet Dent 1974;32:41–51.

321. Lord JL, Teel S. The overdenture. Dent Clin North Am1969;13:871.

322. Prothero JH. Prosthetic dentistry. 2nd ed. Chicago, IL: Med-icodental Publishing Co.; 1916. pp. 476, 519.

323. Sognnaes RF. America’s most famous teeth. Smithsonian1973;3:47.

324. Ettinger RL, Qian F. Postprocedural problems in an over-denture population: a longitudinal study. J Endod 2004;30(5):310–14.

325. Ettinger RL, Qian F. Abutment tooth loss in patients withoverdentures. J Am Dent Assoc 2004;135(6):739–46.

326. Shannon IL. Chemical preventive dentistry for overdenturepatients. In: Brewer AA, Morrow RM, editors. Overdentures.2nd ed. St. Louis, MO: CV Mosby Co; 1980. pp. 322–40.

327. Key MC. Topical fluoride treatment of overdenture abut-ments. Gen Dent 1980;28:58.

328. Brewer AA, Morrow RM. Overdenture problems. In: BrewerAA, Morrow RM, editors. Overdentures. 2nd ed. St. Louis,MO: CV Mosby Co; 1980. p. 345.

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CHAPTER 41

OPERATIONS MANAGEMENT

IN ENDODONTIC PRACTICE

MARTIN D. LEVIN

The establishment of any professional practice shouldinclude the development of a vision that promotesexcellence in both clinical application and perfor-mance. With the advent of new technologies suchas in-office cone beam computed tomography, theemergence of molecular dentistry and medicine, newpharmacogenomics, increased dissemination of knowl-edge on the Internet, and improved electronic com-munications, we are at the threshold of a new era inpatient care. Concurrently, these new technologies,improved relationships, and continual improvementsin clinical and experiential performance require goodmanagement strategies and, ultimately, financial suc-cess to create and maintain an outstanding practice.To accomplish sustainable success, we must not onlyhave mastery of the clinical tools of our profession,but also possess the skills necessary to run a successfulbusiness.

To remain successful, this vision must include thepossibility that your practice will have to undergoboth planned changes to implement new proceduresand the need to respond to developments over whichthe organization will have little or no control. In fact,it has been postulated that today ‘‘more than half ofthe economic value of dental care is derived fromprocedures that were not available just 20 years ago.’’1

To train practitioners and employees, upgradetechnology, and improve client service continually, thepractice of dentistry requires entrepreneurial training.Dr. Harold Slavkin, former director of the NationalInstitute of Dental and Craniofacial Research (NIDCR),recognized the need for business training when he pro-posed increasing ‘‘the education and training of ourstudent learners in the field of leadership and manage-ment of dental practices.’’2 Today’s endodontist mustbe a clinician, infection control expert, entrepreneur,

insurance and financial manager, and human resource(HR) authority.3

Clinical excellence is the hallmark of every trueworld-class practice. What really matters is adoptingan ethical and philosophical level of quality that willenable each practice to do the right thing every time.Basically, we are in the people business, and peoplenaturally align with organizations that value integrity,compassion, quality of care, and high standards ofbehavior. Only by viewing your organization as a col-lection of interdependent systems and processes thatultimately depend on each employee to reach his orher full potential will your practice reach the desiredresult. As outlined by Abraham Maslow4 over 50 yearsago, successful organizations are the ones that genuinelyencourage self-actualization to ensure that people iden-tify and pursue their own unique personal potential.

To this end, this chapter will highlight operational stra-tegies that focus on creating a vision that will fund sustain-able success by building a brand-driven culture withinyour organization that is supported by high-performancehuman systems.

Choosing How You Want to Practice

The healthcare industry is a services profession, andas such has different characteristics than companiesproducing physical goods.5 According to LeonardBerry,6 Distinguished Professor of Marketing at theMays Business School at Texas A&M University,‘‘marketing a performance [e.g., medical services] isnot the same as marketing an object . . . In packagedgoods the emphasis is on differentiating tangib-les through imagery; in services the emphasis is tan-gibilizing the intangible.’’ To truly understand the

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medical services world, Berry spent his sabbatical atthe Mayo Clinic, immersed in day-to-day hospitalprocedures and interactions. He came away with anew appreciation for the importance of reliability asthe basis of services marketing excellence. What he issaying, essentially, is that you have to do the job rightthe first time, every time because ‘‘who wants to travelon an airline whose pilots are usually dependable, [or]be operated on by a surgeon who usually rememberswhere on the body the surgery is to be done?’’

As a services profession, the delivery of dental carerequires both the provider and the consumer to bepresent at the same time. This one-on-one relation-ship gives rise to the potential of real-time customiza-tion, one of the most powerful tools available tohealthcare providers. When you and the patient areworking together to create an agreed-upon result, youcan decide how much, or if any, customization willoccur, and even whether that customization will occurin the front office, the back office, or both. Thisconsultative function should be managed to createvalue that satisfies patient and referrer needs. From acustomer-centered perspective, it means providingwhat both the patient and referring doctor want, ontheir terms, when and how they want it.7

Organizations need to establish a strategic frameworkin order to reach their full potential. This frameworkconsists of (1) a vision for the future, (2) a mission thatdefines what you are doing now, (3) a step-by-stepstrategy to clarify your individual situation and developa program to achieve future objectives, (4) goals andaction plans that guide day-to-day decision making,8

and (5) feedback to see what really works.

VISION AND MISSION STATEMENTSA vision statement is a clearly articulated, future-oriented declaration that articulates what your organi-zation wants to become. Vision statements range inlength from a couple of words to several pages; shortervision statements tend to be easier to recall and use.

This statement should resonate with all membersof the practice and help them feel proud, excited,and part of something larger than themselves. Avision should stretch the organization’s capabilitiesand image of itself. It should give clarity, shape, anddirection to the organization’s future. Do you wantto be the most technologically advanced specialist inyour community? Do you want to achieve a highreturn on your investment? Do you want to be athought leader, a fee leader, or both? Answers tothese and other questions will help you create avision for your practice.

A mission statement is a succinct proclamation of thepractice’s purpose for existence. It should include mea-surable criteria and address such concepts as image,customer demographics, target market, and expectationsfor growth and profitability. Mission statements shouldbe broad enough to incorporate every service providedand should include the practice’s moral and ethical posi-tion, geographic and demographic domain, and theexpectations as well as hopes for growth and profitability.

Once a mission statement is adopted by theorganization, everyone must subscribe to its preceptsor its usefulness will diminish. It is critical that you alignyour practice with your mission so that every interac-tion between employees and patients builds value.Unfortunately, the Workplace 2000 Employee InsightSurvey, conducted by Tom Terez, author of ‘‘22 Keys toCreating a Meaningful Workplace,’’9 found that only23% of US workers say that their company’s missionstatement has become a way of doing business.

Visions and missions are usually linked to strate-gies and goals that are specific, measurable, and shortterm. Once a vision and mission statement has beenadopted and becomes part of the fabric of yourpractice, you can develop an implementation strategyand a list of annual goals. Finally, adding deadlinesand a system of measurement will allow you to con-tinually gauge your progress.

STRATEGIC PLANNINGWhat is a strategy? The word comes from the Greek wordstrategia, meaning ‘‘generalship.’’ While it is difficult tofind agreement on an exact definition of strategy becauseit includes ‘‘thoughts, ideas, insights, experiences, goals,expertise, memories, perceptions and expectations,’’10

almost everyone can agree that it is about the means toreach an end, not what those aims are or how they areestablished. In most successful practices, the leadershipalone is responsible for assuring that the office’s policiesare legitimate and ethical. Strategy, on the other hand, isthe province of both leadership and management, whiletactics are the responsibility of management alone. Inother words, determining the goals of an enterprise ismainly a governance issue, while employment ofresources is the job of management. Keep in mind thatstrategy is a changing perspective of what is required toobtain the ends that have been specified in policies, and isdependent on the actual results as measured by businessperformance. So strategy and tactics actually bridge thegap between resources and policy.

Two useful techniques to evaluate your future prac-tice’s potential for success are the SWOT (Strengths,Weaknesses, Opportunities, and Threats) and PEST

Chapter 41 / Operations Management in Endodontic Practice / 1475

(Political, Economic, Social, and Technological) ana-lyses. A SWOT analysis measures a business proposi-tion or idea. Long-range strategic planners often useSWOT analysis to assess core issues and develop a planbased on current perceptions (Table 1). Practices canalso benefit by completing a SWOT analysis to evalu-ate a competitor.

A PEST analysis helps to measure the externalmacro-environment that affects all businesses. Themost useful analysis for a dental practice will be thesocial and technological analysis portion. The socialsection is where patients’ and referrers’ demographics,class structure, education, culture, and attitudes abouthealthcare are considered. Technological analysislooks at recent technological developments, theirimpact on the value-chain structure, cost, and effi-ciency. For example, should you consider purchasingor leasing a cone beam computed tomography scan-ner, panoramic device, or refer patients needingadvanced evaluation to a center with these capabil-ities? PEST analysis allows for proactive marketingand business development assessment.

SETTING GOALSGoals are plain language statements that describepriorities or actions to be accomplished. Practicesshould have a number of goals, each describing adesired result toward which your efforts should bedirected. Goals set priorities for management and staffand establish measurement parameters for evaluatingsuccess. Goals serve to keep an organization focusedon success and away from activities that tend to dis-tract and drain resources. If the goals are accom-plished, then the business should be a success.

Practice goals are generally derived from missionstatements and describe how the mission will be accom-plished, while mission statements describe exactly whatneeds to be accomplished. A goal should be simple,clearly written, state the conditions that will exist if thegoal is accomplished, and set action-oriented tasks thatyou want to accomplish in 1 to 3 years. Some businessgoals will have a 1-year time frame, while others mayhave longer or shorter time frame. It is not unusual for apractice to have a mix of business goals starting and

ending at different times. Most importantly, a goal needsto be achievable and challenge the people responsible forits accomplishment.

As more employees understand and commit toyour vision for the practice, it is the job of leadershipto continually reaffirm it through every availablechannel of communication, such as staff meetings,or when conversing with co-therapists, and so on.According to Lionel Urwick’s11 classic Harvard Busi-ness Review article, 1956, ‘‘There is nothing which rotsmorale more quickly and more completely than. . .thefeeling that those in authority do not know their ownminds.’’ Once the plan is created, be ready to changeit. Strategic plans are dynamic, living documents thatare not a once-a-year project, but can be modifiedrepeatedly as it needs warrant. Strategic planning isone of the key activities that forces organizations tofocus on the right priorities to foster growth. In theend, all strategic planning models are goal-based andrely on clearly defined, understood, and communi-cated action steps. A strategy is not useful, however, ifit is not realized. A Fortune Magazine study hasshown that 7 out of 10 CEOs fail because of poorexecution, not because of bad strategy.12

PRACTICE MODELSUnlike the practice of medicine, which is becom-ing increasingly complex and business-like, MarjorieJeffcoat,13 the Morton Amsterdam Dean at the Schoolof Dental Medicine, University of Pennsylvania, saysthat ‘‘dentistry has remained a profession dominatedby small, independent practices.’’ In fact, KathleenRoth, president of the American Dental Association(ADA), in a 2007 address to the Small Business Com-mittee of the U.S. Congress, reported that over 90% ofpracticing dentists are in the private sector and 85%of those practitioners operate independent solo prac-tices.14 But the need to investigate organizationalalternatives is becoming more urgent with the expec-tation that there will be a sea change in the way healthcare is organized and funded in the future. Whiledentists may continue to practice independently,other dental practice models will show strong growthand evolve as business entities.

Table 1 SWOT (Strengths, Weaknesses, Opportunities, and Threats) Anaylysis

Strengths: What you do better than the competition Weaknesses: Things that the competition does better than you

Opportunities: Trends, changes, and characteristics of your market

that may offer opportunities for your business now or in the future

Threats: Trends and changes associated with your market that may present

your business with problems either now or in the future

This SWOT analysis form measures a business proposition or idea by assessing core issues. Most practices can apply the ideas developed here to understand their

current position and help plan future initiatives.

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Armstrong et al.15 have postulated that some prac-tices adhere to the ‘‘service factory model,’’ wherelow cost and standardization predominates, deliver-ing consistent but standardized service. Conversely,other practices act as ‘‘service theaters,’’ or nichepractices, where a select clientele undergo pre-mium-priced procedures that are individualizedand scripted for maximum effect. Patients choosethis type of practice if price is no object. They wanta high-tech approach, presented with personal atten-tion in an office that rivals the ambiance of a finehotel. Employees are not just hired here; they aretrained to serve as members of a team that values ahigh-touch, patient-centered experience.

Other attempts to categorize practice models havebeen proposed by the Dental Trade Alliance (DTA).Jeffery Lavers,16 Marketing Director of 3M ESPE,says that continual change in the dental marketplaceis certain and will be influenced by demographics,technology, disease patterns, patient behavior, and ser-vice choices and dental workforce. Providers of dentalcare, for example, will be reduced from their currentlevel of 130,000 full-time equivalent practicing U.S.dentists by more women providers practicing fewerhours and lower numbers of dental school graduatesthan in the past. These factors and an associatedincrease in the U.S. population will continue to decreasethe dentist/population ratio.

The DTA has proposed the following emergingpractice models, which it predicts will provide over60% of all dental services by 2010 (reproduced bypermission of the DTA):

Ready Access Model—High-process standardiza-tion, convenience-oriented, highly flexible operat-ing systems, focused on a dynamic ‘‘retail’’ serviceexperience

Tech Station Model—High level of technicalresources, procedural leading edge, ‘‘gee-whiz’’experience backed by relatively high-touch patientcommunication

Small Group Model—Well-integrated staff withbroad range of scope, seamless teamwork of staffgeared to provide service efficiency and through-put

Cosmetic Center Model—A variation on theconventional practice with heavy emphasis onelective care in personal aesthetics and restorativeservices

Super Norm Model—Emphasis on high-touch,service-intensive patient experience, customer

intimacy, and high-margin work with demandingpatients

Armstrong’s service theater approach is similar tothe ‘‘super-norm model’’ proposed by the DTA’sdescription of emerging practice models, with anemphasis on a customer-centered approach that treatsdemanding patients and produces high-margin work.Practice models will continue to evolve, and somepractices will incorporate elements of several businessforms. One practice model may use technology whilealso providing cosmetic procedures based on personalaesthetics and high-end customer service. What doesall of this have to do with your endodontic practice?Simply put, running a successful practice requires apowerful vision of where you want to go.

Starting a new practice, associating with an estab-lished endodontic practice, or choosing a hybridformat is the first of many decisions that every endo-dontist will have to make when beginning his or hercareer. What follows is a short primer on the risks andbenefits of three employment options.

NEW PRACTICEWhat are the benefits of starting your own practice?You will have complete autonomy in setting practicepolicies and making decisions. Every decision, that is,the selection of particular equipment and designingtreatment protocols, as well as the selection ofemployees, will be yours to make. When it is yourbusiness, you dictate the way things are done. Thescheduling of employee and your own vacations is atyour discretion. Then there is personal fulfillment.Owning and running your own business can be moresatisfying than working for someone else, and manypractitioners enjoy the respect they earn from theirpeers for having the courage to go out on their own.When you own your own practice, you may have toforgo a regular paycheck, but the upside earningspotential may be greater than any other alternative.If these aspects have strong appeal, then starting yourown practice should be considered.

There are formidable risks to starting your ownpractice, and a careful analysis is critical. As a solepractitioner, you must spend the time to research alldecisions yourself or engage advisors to assist you inthis process. Solo practice will require an emergencycoverage arrangement with another practitioner whenyou are out of town. You will have no immediate peerconsultation to explore the treatment of difficultcases. And you will face a greater risk of losing yourinvestment. Although relatively rare, some practi-tioners just cannot earn sufficient income to remain

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profitable. This may occur as a result of choosing apoor location, competing unsuccessfully with estab-lished neighboring practices, or assuming too muchdebt. Finally, opening your own business can come ata high personal cost. It will take a lot of energy andpersonal sacrifice to get going, likely necessitatingworking at night and on weekends, infringing onpersonal time.

ASSOCIATE-EMPLOYEE OR ASSOCIATE-INDEPENDENT CONTRACTORFor a recent graduate with little or no prior practiceexperience, the benefits afforded by having a transi-tional period with an established practice can be pri-celess. Serving as an associate-employee allows thenew practitioner to assume the reputation of the othermember(s) of the practice, and by inference, morequickly establish a good professional reputation ofhis or her own. Other benefits include practice own-ership opportunities, no initial financial investment,immediate patient flow, peer clinical consultation,shared emergency coverage, and the freedom to moveeasily to another locale if a change is desired.

Risks of the associate-employee and associate-independent contractor path include the lack of totalcontrol over the practice, loss of individuality, andthe legal constraint of practicing with a restrictivecovenant. A restrictive covenant is a contractualagreement usually between an associate and his orher employer that prevents the associate from practi-cing in a certain geographic area for a specified timeperiod after termination of employment. Theseagreements are used by employers to protect theirinvestment in start-up costs associated with bringingon an associate and their referral network from com-petition. Most contracts will include a restrictivecovenant, also known as a non-compete agreement.Generally, courts have held that restrictive covenantsare enforceable, but not in all states or under allconditions, so get good legal advice.

Associate-independent contractors are independentpractitioners who provide services to a dental practiceon a contractual basis. This form of practice must becarefully structured to remain in compliance withInternal Revenue Service (IRS) guidelines. Under cur-rent IRS rules, the practice owner cannot control boththe means of work and the results of the independentcontractor’s efforts. No benefits, retirement plans, oremployment taxes are paid by the practice for theassociate-independent contractor. Additionally, thepractice owner cannot furnish supplies, equipmentand instruments, impose safety precautions, plan

work to be done, control office hours, or assumeliability stemming from the independent contractor’sperformance. The associate-independent contractorrelationship must be properly constructed to avoidincurring significant taxes, interest charges, andpenalties. This is the province of an attorney withexperience in such transactions.

HYBRIDA hybrid form of employment may include anycombination of the following part-time schemes:(1) serving as an associate-employee or associate-independent contractor in an established endodon-tic practice, (2) starting your own practice, and(3) serving as an independent contractor in oneor more general dentists offices. The latter will notlikely result in a stable long-term practice situation,and should be viewed as a temporary solution, atbest. The value of this arrangement is that it canserve as an interim step that can financially sustainthe new endodontist until he or she builds a referralbase.

Winning Management Practices

Forming and operating an endodontic practice is a com-plex and nuanced undertaking. The notion that we aresimply a profession and not also a business seekingfinancial success is to miss the opportunity to generatefair compensation for your knowledge and professionalskills. Generating a healthy revenue stream is the onlyway to ensure that you can continue to provide the mostadvanced care available. In fact, Joe Blaes, editor ofDental Economics, states that ‘‘it is impossible for youto stay in practice without a reasonable profit.’’17 Howdo you learn the basics of practice profitability? By study-ing other businesses to gain insights about operationsmanagement and best practices.

What really works in the business world? In thelandmark Evergreen Project, 50 leading academics, ledby William Joyce, Professor of Strategy and Organiza-tional Theory at Dartmouth College’s Tuck School ofBusiness, and Nitin Nohria, the Richard P. ChapmanProfessor of Business Administration at the HarvardBusiness School,18 looked at 40 narrowly definedindustries with $100 million to $6 billion in grossrevenue and determined that winning companiesadopted four primary management practices and twoof four secondary management practices. Adapting thisscheme to endodontic practice, the following sectionssummarize the study’s findings:

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PRIMARY MANAGEMENT PRACTICES

1. Strategy: Develop a step-wise plan to clarify yourindividual situation and develop a program toachieve future goals:a. A clear value proposition: What patients and

referrers want most are results and process qual-ity. That the endodontic treatment works andthe patient can maintain their dentition and thetreatment meets or exceeds the specifications ofthe referring doctor is only the ‘‘results’’ part ofthe equation. ‘‘Process quality’’ measures howthe patient was treated. This is the experientialpiece, and endodontic treatment is usuallydefined by patients in these terms. At the endof the day, when patients ask the question‘‘How was I treated?,’’ they are actually assessing

process quality. Remember, there is no reason-able way for patients to easily understand thefive points of the technical side of treatment.

b. ‘‘Outside-In’’: To put this concept in perspec-tive for our profession, it means understandingwhat your patients and referring doctors wantand creating systems to satisfy those needs,from their perspective. Finding out exactlywhat patients and referrers deeply value andhow to deliver it with passion is the holy grailof practice excellence.

c. Continually measure and refine: Practice metricscan be an important indicator of your success.Understanding the referral process, measuringnew patient referrals, and tracking ‘‘fading refer-rals’’ are examples of ways to measure the successof your efforts (Sidebar 1).

MEASURING CUSTOMER DEFECTIONS

In today’s competitive marketplace, success in a referral-based business like endodontics is all about buildingrelationships. According to Frederick Reichheld,105 a business consultant and author of The Loyalty Effect, abusiness invests in customers, and premature customer (e.g., referring doctor) defections will ultimately resultin diminished profitability.

Reducing defections (also referred to as ‘‘fading referrals’’) begins with measuring the rate of defection.According to Reichheld,106 in another article in the Harvard Business Review, ‘‘customer defection is one of themost illuminating metrics in business.’’ Some defections are normal in any business and in rare cases they caneven be welcomed. A percentage of referring doctors will never be loyal and can even diminish morale andincrease stress if they continue to send patients. But, such welcomed defections are few and far between. Inmost instances, it is important to preserve and encourage continued referrals. So, what action should you takeif a referral begins to fade? The best approach is to contact the individual who has stopped making referrals andfind out why. Always avoid getting defensive, practice active listening, and no matter what you hear, thankthem for their time and candor. You may not get these referrers back in the fold, but you may learn how tokeep others from defecting in the future.

Once you loose a referrer, replacing him or her will not be easy nor inexpensive. In fact, Reichheld’s survey of100 companies in 24 industries found that longer customer retention led to increased profits. No surprise here.Many companies make the mistake of not even keeping track of customer defections because they are unawareof the cost to replace them. And many business owners find that customer defections are hard to track,especially when referrals are based on business cycles and sometimes involve only partial defections. Measuringdefections can be unpleasant and remedial action is often difficult to accomplish. Even so, it is important toquantify such defections and set goals to improve those relationships.

Measuring referrals is a necessary part of operating a referral-based practice. Look for practice managementsoftware that analyzes referral trends within a given time period. It should take just a few mouse clicks to getthe information. Some industries report that reducing defections ‘‘by as little as five points ... can doubleprofits,’’106 and monitoring the ‘‘fading referral’’ to measure declining business will yield valuable insights thatneed to be addressed immediately.

The most profitable companies champion customers, recognizing that the longer a company keeps itscustomers, the more successful it will be. Loyal customers result in more profits, because loyal customersbuy more, take less of a company’s resources and are willing to pay a price premium. Why? Because they do notwant to start with new people either. Best of all, loyal referrers and patients are more likely to refer newpatients.

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d. Keep focused: Understand your core businessand focus on the convergence of what you dobest and most profitably with what yourpatients really want. Consider a focusingmatrix showing the relationship between whatyou do best and what your patient’s value most(Table 2). When the two converge, you have awinner!

2. Execution: Deliver products and services thatconsistently meet patient expectations. Everybusiness tries to set their customer’s expectations.This research project has demonstrated that con-sistently satisfying customer expectations is farmore important than exceeding expectations inone or more areas and falling below the grade inanother. The customer will judge and rememberthe worst performing parameter or interaction,and his or her negative experience will oversha-dow any exceptional service provided. Anotherway to improve is to eliminate waste and increaseproductivity by constantly evaluating operationsand making changes that improve the bottomline.

3. Culture: Inspire to do your best. Every officeemployee looks to the doctor(s) and officeadministrators for leadership. We must continu-ally refine and measure our care and motivate themembers of our office team to strive for excel-lence. Rewarding achievement with acknowledge-ment and remuneration based on performancewill create a fulfilling workplace.

4. Structure: Simplify. Placing the best employee(s)close to the customer is another way top busi-nesses achieve outstanding results. While mostbusinesses promote the highest achievers to thenext level in a vertically structured organization,this action usually takes the best and brightestand moves them away from the customers who

interact with the company. So consider this actioncarefully when reorganizing your staff. Keeping thevertical structure will simplify administration andwill allow the staff with the best people skills to stayclosest to those they serve.

SECONDARY MANAGEMENT PRACTICESThe Evergreen study also found a correlation betweenany two of the following four secondary attributes:

1. Talent: The value of developing and keeping greatemployees cannot be underestimated; most win-ning companies reward exemplary employees tokeep them motivated. These rewards can takemany forms, among them salary, benefits, vaca-tion, and probably most importantly a safe andinspiring working environment that drives perso-nal achievement.

2. Innovation: Advanced services and technolog-ies are critical to your success. Working withsophisticated practice management software,advanced communications between the officeand co-therapists, and treatment technologiessuch as microscopes and digital radiographic areincreasingly important and expected.

3. Leadership: Trust and confidence in top leader-ship is one of the single most reliable predictors ofemployee satisfaction. Leaders help employeesunderstand the organization’s overall businessstrategy and how they can contribute to achiev-ing key business objectives. Sharing informationand communicating about performance in asmall office environment by non-professionalHR managers/doctors can be challenging. Toimprove overall performance, rewarding indivi-dual employees and managers for leadership andcreativity is a must.

4. Mergers and partnerships: Partnering withanother practice to maximize the value of diversetalents is often overlooked in cottage industriesand small businesses. Strategic alliances and mer-gers of individual practices to provide better cov-erage and economies of scale can produce bene-fits. This can take the form of an alliance betweenseveral endodontic practices or the combining ofan endodontic practice with a periodontal prac-tice, and so on. Establishing a solo group wheretwo or more endodontists practice in the samefacility with shared common areas and adminis-tration but separate practice entities is anotherpossibility to economize and protect against theconsequences of disability or death.

Table 2 The Focusing Matrix

What you do best ‘‘Stop’’ ‘‘Go’’

What you do not do best ‘‘Stop’’ ‘‘Go with Partners

What your patients

do not value

What your patients

value

The Focusing Matrix demonstrates the convergence of what you do best and

what your patients and referring doctors value most. For example, take one-

visit endodontic procedures. These are valued by your patients and referrers

and are more efficient for your office to perform. Put them in the ‘‘Go’’

category. If a procedure falls in the ‘‘Stop’’ category, consider a change.

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How to Get Started

Opening a new office for the practice of endodonticswill require many months of planning. The projectshould begin with identifying your objectives. Do youwant to establish a boutique or niche practice or amore traditional practice? Will you accept insuranceassignment or participate with a preferred providernetwork or health maintenance organization? To suc-ceed, you will need to make sure your practice will beappropriate to the needs and expectations of yourcommunity.

Begin by creating a business plan, develop a time-line, and establish an office location that will accom-modate the unique requirements of an endodonticpractice. Because endodontic offices require specialplanning, the time needed for construction and instal-lation will far exceed the time and expense requiredfor a typical non-healthcare facility. Ranking variableslike location, parking, home-office travel times, ame-nities, and proximity to other medical and dentalpractitioners are necessary parts of the decision-making process. To get this right, you will need theservices of an attorney, accountant, banker, commer-cial real estate broker, architect, interior designer,dental equipment supplier(s), and computer and tele-phone system engineers.

FIRST THINGS FIRST: CREATINGA BUSINESS PLANThe two essential elements of a good business plan area winning vision and a clear path to profitability. Toborrow money, carefully design the plan to ‘‘sell’’your vision to a skeptical bank loan officer. The busi-ness plan should include the following:

1. A persuasive introduction to describe yourplanned practice, including features and benefits,and a request for funds.

2. A statement of the purpose.3. A detailed description of how an endodontic

practice works, office location overview, whetheryou will have employees, and who will provideyour equipment and supplies.

4. An analysis of your market demographics (whoare your patients?).

5. An evaluation of your main competitors.6. A description of your brand strategy and how you

will use marketing to drive your brand to top-of-mind-status (see ‘‘Branding: Enabling Your Prac-tice Success’’).

7. A resume setting forth your educational and pro-fessional accomplishments.

8. Detailed financial information, including yourbest estimates of start-up costs, revenues andexpenses, and your ability to make a profit.

Help in designing a business plan is available from theU.S. Small Business Administration (SBA) and onlinesoftware guides like Business Plan Pro (Palo Alto Soft-ware, Eugene, OR). Focus on creating a polished planthat can be presented to several bankers and their loanboards for consideration. The better it looks, the morelikely you will get a favorable loan offer. If you are self-financing, concentrate on financial projections,because the cost of services, sales revenue, and profitwill all figure prominently in how much you will haveto invest. Remember that starting a new professionalbusiness will require money to market the practice.Very few offices today, especially in crowded urbanmarkets, can just hang out a shingle and expect to bebusy. Good planning requires making educatedguesses about income and spending, based on thefollowing projections:

1. A break-even analysis to determine if you willmake money:a. Projected collectionsb. Fixed and variable costs (estimate)c. Gross profitd. Break-even revenue

2. A start-up cost estimate to evaluate the amount ofmoney needed just to open the door on the firstday of practice.

3. A profit-and-loss analysis to refine the month-to-month projection of profits for the first yearof practice.

4. A cash flow projection to ensure that even if yourbusiness is profitable, there is enough money onhand to operate from month to month.

No business plan would be complete without consid-eration of what business structure the practice will take.Keep in mind that this decision will affect your personalliability as well as the amount of tax you and yourorganization will pay. Whether you choose a ‘‘C’’ or‘‘S’’ corporation, a limited liability company (LLC),limited liability partnership (LLP), general partnership,or sole proprietorship, your attorney and accountantwill need to provide advice.

CHOOSING AN OFFICE LOCATIONChoosing where to practice is one of the most impor-tant decisions a new practitioner will make. Familyconsiderations, personal preferences, weather, careeropportunities for your spouse, and lifestyle issues are

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among some of the considerations that should governyour decision. Establishing a successful endodonticpractice will require a location that will provideenough new patients to support the practice’sexpenses and result in the best opportunity for youto utilize your skills. Because the number of dentistsin postdoctoral endodontic programs continues toincrease faster than any other dental specialty,19 prac-tice location will prove to be a key predictor of success.Studies by Wright,20 and Solomon and Glickman,21

using sophisticated statistical analysis, clearly establishthe relationship between the location of general den-tists and the location of endodontic offices. Becauseendodontic practice is referral-based, the proximity ofa referral network, followed by adequate populationand other criteria such as socio-economic characteris-tics, are all variables that will affect the economics ofyour practice.

The economic potential of your proposed office loca-tion should be appraised to determine its professionaldesirability. People living in similar neighborhoods gen-erally exhibit similar lifestyle and spending profiles. Oneof the easiest ways to learn about your clientele is tounderstand their geodemographical classifications. Thesedata, available from vendors like Business InformationSolutions (ESRI BIS, an internationally recognized pro-vider of information services), will allow analysis ofclinic site locations by creating a visual depiction of datawhich is spatially referenced to the earth, also known asgeographic information systems (GIS) mapping. GIS-generated information will greatly improve your busi-ness planning and allow you to base location and growthdecisions on the best available information. A new typeof classification introduced by ESRI BIS, called the‘‘Community Tapestry’’ segmentation system, providesan accurate, detailed description of America’s neigh-borhoods. U.S. residential areas are divided into 65segments based on demographic variables such as age,income, home value, occupation, household type, edu-cation, and other consumer behavior characteristics.ESRI BIS offers market surveys that provide a detailedlook at data within various radii around a given geo-graphical address. This is called a ‘‘Market ProfileReport’’ and is based on the updated U.S. Census,including 5-year projections. Reports can also beordered with specific filters, such as a plot of all generaland specialty practices in the zones of interest. Youcan find them on the Web at http://www.esribis.com.Also, ESRI BIS offers a free Web-based lookup of demo-graphic data based on ZIP codes, but ZIP codes will notprovide adequate specificity for making a final decision.

Further analysis can be performed by purchasing alist from your state dental society in Excel format, and

then using a program such as Microsoft MapPoint toplot the data. Of course, there is no guarantee ofsuccess with any particular location, but a poor choicemay lead to economic hardship. It is critical that youcreate a comprehensive plan to assure that your pro-posed site is architecturally and financially sound.Plan on specifying about 400 to 500 square feet peroperatory in your new office.22

According to Gregory L. Morgan,23 ManagingDirector of Sperry Van Ness – Morgan Realty Advi-sors, specify your geographic parameters, spacerequirements, parking availability, modes of access,and street exposure if applicable. Then engage anexperienced commercial real estate leasing profes-sional to canvas your prospective area and match yourrequirements with properties using real estate data-bases, brokerage relationships, publications, and theInternet. Comparing the economics and qualitativedifferences between properties and market informa-tion is where a commercial real estate leasing profes-sional will provide essential guidance. Hopefully, youwill have several options to review, creating a compe-titive atmosphere where multiple landlords are com-peting for your business. As you will learn earlyon, the effective rent can be based on one of severalformulas, and extending these costs over many yearscan add up to a significant difference. Even if you areespecially focused on one of these locations, it isimportant to go through the exercise of requestingproposals from several property owners and man-agers. Some landlords will offer concessions in areaswhere others will not, helping you to identify the mostimportant considerations for your business: propertylocation, economics, and functionality. Analyzing theproposals will then help you request aggressive butfair economic concessions from the finalists based onwhat other competing landlords have offered.

The next step is to decide on the number of opera-tories and what supporting facilities will be required.Engage an architect or dental office designer to drawbasic floor plans and confirm that adequate plumbingand electrical infrastructure needs are met. Now, withseveral lease proposals in hand, you should meet witha real estate attorney for further analysis.

According to leasing attorney Charles J. Levin,24 someof the attributes of a successful commercial lease aresummarized as follows: (1) lease terms and conditionsare expressed in a complete written lease with no oralagreements and understandings; (2) all contingenciesare considered and resolved; (3) lease terms and condi-tions are aligned with your needs; (4) the leased premisessuits your needs; (5) you have protected yourself fromoperating expense charges that are not customary and

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you understand what to expect with those that arepassed through; (6) there are no defects like possiblenoise, odor, vibration, or other similar problems; (7)you have warranties protecting you from issues such aszoning, water quality, mold, asbestos, Americans withDisability Act (AwDA), and so on; (8) you have thor-oughly reviewed the build-out letter with your architectand contractor and included all necessary details in thelease; (9) you have expressly excluded certain types ofobjectionable tenants from being in the building or onyour floor (e.g., music school, barbeque restaurant, andsocial security office); (10) you have flexibility to renew,expand, and terminate; (11) you have option to pur-chase, if appropriate; (12) other tenants have no majorcomplaints; (13) you have looked into the future andconsidered all of the possibilities with respect to issuessuch as fire and casualty, condemnation, changes ingovernmental requirements, assignment and subletting,and the many other issues that can arise; and (14)you, your commercial real estate leasing professional,attorney, and architect have all reviewed your officeselection. Lastly, create a ticker file in your office man-agement software as a reminder of notification datesmemorialized in your lease.

Levin further emphasizes the importance of youbeing engaged in all aspects of the negotiations andthat you understand the significance of each and everyprovision of the lease as it is being negotiated. It is amistake to hand the lease to your attorney for nego-tiation and expect that your interests are being pro-tected without your involvement. There are manyaspects of the lease that combine both business andlegal issues that will have a profound effect upon thesuccess of the practice. The selection of an experi-enced commercial real estate leasing professional andreal estate attorney cannot be overemphasized becauseof the complex and nuanced nature of leasing spaceand the long-term and potentially devastating impli-cations of getting it wrong.

Once the lease is executed, the next step is contact-ing the telephone company to obtain a telephonenumber and secure a listing in the local phone direc-tory. Many telephone providers will allow you toselect a unique telephone number without charge orfor a small fee. Generally, it is only necessary to secureone number, which will serve as your main trunk line.Additional numbers can be secured at a later time foruse with multi-line phone systems, to avoid paying forreserving hidden numbers prior to the opening of theoffice. Today, most offices will have a choice betweenseveral trunk line providers and systems, such as cop-per wire or fiber optic. Use of Internet phone servicesover fiber-optic connections, such as Voice over IP, is

becoming more popular, and packaged with Internetconnectivity and television services, may prove aviable alternative to traditional service.

After securing a telephone number and phone booklisting, order the practice management software and acomputer workstation which will become the front desksystem. Once setup, this workstation can be located off-site to configure your practice management softwareand allow training of new employees. Every endodonticpractice, including a de novo practice, must have prac-tice management software to manage appointments,prescriptions, reports, and other communications withreferrers, not to mention the financial aspects of treat-ment and insurance.

CREATING A WINNING OFFICE DESIGNAlthough building a new office from an empty shell isa daunting challenge, it provides the opportunity to setup the office to your specifications, within budget andspace constrains. A key element to insuring success isthe early involvement of your design team—and thedesign team starts with your architect or dental designfirm. Try to choose an architect who is familiar withthe design of medical facilities, the AwDA (Americanswith Disabilities Act)25 standards, hygiene require-ments, and your local building codes. By helping youdefine the building project, architects can providemeaningful guidance for the contractor and other con-struction professionals. They can conduct site stu-dies, help secure planning and zoning approvals,perform a variety of other pre-design tasks. Evaluatefor handicapped patients, transportation, parking,and general convenience. When experienced archi-tects are involved at the earliest planning stage, theygain opportunities to understand your business,develop creative solutions, and propose ways toreduce costs. The long-term result is a facility thatadds to the productivity and image of the practice.Specialty architects who design just dental or health-care facilities are also an excellent option, and themore endodontic offices they have designed, thebetter probability that all details will be considered.The American Institute of Architects26 provides goodresources on their Web site and lists numerous stan-dard agreement forms that can be tailored to thetypes of services that are required.

Steven Covey’s27 maxim ‘‘begin with the end inmind,’’ plays a large part in creating your desiredoutcome. What do you want your office to look like?How will patients and referring doctors be bestserved? Of course, ownership of your space in eithera condominium or a stand-alone building that you

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are purchasing or building will require special con-siderations.

After the plans are approved by the building owner,your architect and/or dental designer will be respon-sible for meeting with you and any interested con-tractors to explain the scope of the project and solicita quote for construction. The following architecturaldrawings and specifications will need to be avail-able: (1) site plan; (2) demolition plan, if applicable;(3) reflected ceiling plan; (4) mechanical plan, forexample, smoke/fire detectors and fire annunciators,sprinkler system, heating, and cooling; (5) electricalplan, for example, power, telephone, and computerinstallation; (6) plumbing plan; (7) millwork; and(8) finish schedule, for example, flooring, wall cover-ings, and paint. The contactor will generally beresponsible for getting approval from local buildingofficials to begin construction.

Designing the office for new and even future tech-nologies will require some coordination between thevarious planners of your space. The wires and cablesmust be installed and integrated for the practice man-agement system, digital radiography, entertainment,power, fire and smoke annunciators, security systems,and climatic systems.

Design Aesthetics

According to Schmitt and Simonson,28 ‘‘aesthetics isone of the major satisfiers in consumers’ experientialworlds.’’ They state that intangibles like experiencesbecome key selling points when services are perceivedas the same across an industry.

How can Starbucks charge over $4 for a cup ofcoffee? It is because they provide experiences that cus-tomers can see, hear, touch, and feel—experiences thatadd value and allow for premium pricing. In the sameway, your practice will become identified with certaintraits that create a practice image, requiring ‘‘a carefulmapping of a strategic vision to create sensory stimuliand communications that evoke that vision – thatinstantiate the identity’’.29 It is important to establisha style that is consistent throughout everything yourpractice does, from your Web site, to your brochure, tothe design of the office interior. Bloch,30 in his researchto conceptualize consumer reactions to a product’sdesign, says there are three basic consumer responses,namely, ‘‘cognitive, affective and behavioral’’. He goeson to state that product form—or in this case officeaesthetics—influences behavioral responses thro-ugh cognitive and affective responses and are basedon individual tastes and preferences.

Research in the organizational sciences has shown adirect relationship between office design and impres-sion management. The physical environment will con-vey social messages to your patients. Consider designingwith positive visual impact, such as added accent light-ing, dry-wall soffits in key areas, upgraded ceilings, anenhanced level of detail and color balance, pleasant art-work and furnishings, and fabrics to further establishyour desired image. Keep in mind that some businesses,such as Starbucks, have left the traditional marketing totheir competitors, differentiating themselves throughthe inviting ‘‘look’’ of their hip aesthetic that evokes asatisfying experience.30 Some of the ‘‘don’ts’’ when itcomes to office design are creating physiological bar-riers, that is, sliding glass enclosures between patientsand the patient coordinator, showcasing your hobbies;unclean, inexpensive, or misarranged furniture; and off-putting signs in the reception area [a big no-no, with theexception of a Health Insurance Portability andAccountability Act (HIPAA) notice, if applicable]. Signsthat tell patients about office policies, in general, areunwelcome reminders of what your office personnelshould have advised either verbally, or in the office’sliterature or Web site in the first place.

Branding: Enabling Your Practice Success

Dental practice begins as a journey after dental schoolwith little or no training in the business aspects ofpractice. Unfortunately, talent and education aloneare not enough to ensure success in our increasinglycompetitive healthcare marketplace. Getting andkeeping patients in our endodontic practices willundoubtedly become more challenging, especially inmature urban settings. In order to develop long-term,directed growth, we must learn to manage our prac-tice building efforts through trial and error, intuition,reading, continuing education, and use of manage-ment consultantancies.

Before we address the ins and outs of practice opera-tions, we should first explore the case for concern, themeaning of branding, and ultimately how to build abrand-driven culture within your organization. At theend of the day, building you brand in a way thatenergizes all referrers, patients, vendors, and employeesmust become the mantra of your operational strategy.

THE CASE FOR INCREASED CONCERNIn the United States, we are facing many new challengesin private endodontic practice. Endodontics is one ofthe smaller clinical specialties in dentistry, with about

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4,000 practicing clinicians in 2007, and a population toendodontist ratio of about 75,000 individuals per endo-dontist. However, with our population projected at 340million in 2035, and with endodontists graduating andleaving practice at approximately the same rate as today,we are projected to have approximately 6,580 activeclinicians or a population to endodontist ratio of54,270 individuals per endodontist. At current gradua-tion rates, the number of dentists completing endodon-tic residency programs has been increasing faster thanthe number of general practitioners, and as a conse-quence, the practitioner to endodontist ratio has alsobeen declining. The vast majority of endodontists prac-tice in the Northeast and West Coast areas, and ifmisdistribution trends continue, the number of over-served areas will continue to increase with resultantcase-load challenges. Other factors, such as the higherrelative failure rates in restorative materials like resins,general dentist busyness, and increased productivityamong all practitioners will continue to be some ofthe issues affecting the profession.31 A report by theDTA concluded that up to 40% of all practices are notreaching their full production. By the year 2010, it hasbeen postulated that less than 40% of all dental care willbe provided by non-owner doctors rather that moretraditional practice models.32 The competitive land-scape will continue to change, according to Eric Solo-mon,33 Professor of Public Health Sciences at the BaylorCollege of Dentistry, in his Dental Economics article‘‘The Future of Dentistry.’’ He predicts that the numberof specialists in dentistry will increase from the currentlevel of 20% to 27% by the year 2020,’’ leading to anincreasingly competitive marketplace for the new spe-cialist. The days of opening a new office in a majormetropolitan area and instantly generating a sustainablefinancial model are becoming increasingly rare.

Increasing competition, demographic shifts, marketsaturation, bunching of endodontic practices inalready crowded urban centers, insurance companycontrol, and an insidious lack of customer loyalty willalways challenge endodontic practices in the mostdesirable markets. Central to meeting these challengesis creating a brand identity that consistently conveysour special skills to referring doctors and patients.What follows is a summary of branding basics, withan emphasis on the connection between best businesspractices and the dental profession.

UNDERSTANDING YOUR BRANDWhat is a brand? A brand is simply a promise—theexpectations that exist in each customer’s mind abouta product or service. According to John Hagel,34 a

business strategy consultant, in the past, a brand usedto say, ‘‘If you buy this product or buy from mycompany, you can rely on me because of the attributesattached to the brand.’’ He goes on to state that we areseeing ‘‘a new kind of branding emerge, a much morecustomer-centric branding, where the promise is, ‘Iknow you as an individual customer better than any-one else, and you can trust me to assemble the rightproducts or services to meet your individual needs.’’’Brands are imbedded in our minds and used in ourdaily lives, like ‘‘FedEx that photo to San Francisco.’’Your brand is your personality; brands are the reasonthat companies exist, and they are based on multipleexperiences over time. These experiences, from thepatient intake process through treatment and post-treatment interactions, need to be delivered with con-sistency and be perceived as unequaled relative to thecompetition. In short, your patient’s and referrer’sexperiences need to result in deep, trust-based rela-tionships which generate loyalty. Your brand shouldreflect a high level of education, proficiency, and con-fidence that you are offering the best care.

While brands speak to the mind, brand identity orbrandmark is the sensory expression of a brand. Youcan touch it, hear it, feel it, and it increases the custo-mer’s consciousness and builds loyalty. Your brand-mark can include a name, design, or symbol thatvisually represents the value of your practice beyondits functional purpose. The velocity of life in the futurewill inevitably demand that brands leverage the powerof symbols. Whether it is a photograph, mark, graphic,or typographical image, which can be as simple as thepractice name written in an artful font, symbols cantrigger recall and stimulate emotion. A brand identityhelps to manage perceptions of your practice anddifferentiates it from other practices.

Offices must deliver their services to create valuethat relies on understanding results and process qual-ity from the referrer’s and patient’s perspective. Whenit comes to understanding your clients, according toMarty Neumeier,35 a branding consultant, ‘‘Brand isnot what you say it is. It is what they say it is.’’Although branding is a simple concept, it is not thateasy to accomplish. It takes a long-term commitmentand hard work.

In the early 1990s, brands were a series of market-ing tactics like the advertising icons made famous byNike, Alka Seltzer, and even KFC. Brands now havestrategic importance, brands result in deep, trust-based relationships which in turn garners customer’sloyalty. Products and services need to be deliveredwith consistantly high level of quality and value, per-ceived to be unparalleled relative to the competition.

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Adopting this brand-driven approach, ‘‘where makingthe brand the central focus of the organization clari-fies what is ‘on-brand and what is off-brand’’’.36 Thenthe entire organization needs to adopt this brand-driven approach to guide critical business decisionsas well as determine appropriate staff behaviors.Building a brand-based culture is simply not a quickfix program. It requires a solid dedication to theorganization’s brand vision and an understandingthat branding cannot be overemphasized an overallstrategy.

As we learned in the beginning of this section, abrand is a promise that defines a patients’ value pro-position that both their treatment and their experi-ence will be as expected or better than expected. ‘‘Ithas meaning, prestige, and presence, and it helpsconfirm what is expected’’.37 The treatment per-formed must be unrivaled and the patient and referrerexperience must be unequalled. According to Pro-phets 2002 Best Practices Study,38 there are threemain goals of any branding strategy: (1) increasingcustomer loyalty, (2) differentiating your organizationfrom the competition, and (3) establishing marketleadership. Let us look at each of these goals andhow they affect practice success.

1. Increasing customer loyalty: A classic study byXerox in the 1990s (Figure 1) looked at satisfac-tion and found that highly satisfied customerswere six times more likely to repurchase a Xeroxproduct than a merely satisfied customer.39 Thismeans that every highly satisfied patient willdemonstrate repeat behavior and require muchless effort on your part to maintain their loyaltythan patients who are just along for the ride. Evenmore important, a patient who repeats theirbehavior is much more likely to continue repeat-ing it, becoming more profitable as time goes on.For example, it takes the average credit cardcompany 3 to 4 years of marketing effort toattract a new customer, or 7 to 10 times the costof merely maintaining an existing customer. Anincrease in customer loyalty of just 2% will equalthe equivalent of a 10% cost reduction program,and an increase of 5% in loyal customers candeliver 95% greater profitability over the lifetimeof that customer.40 Even more striking is that50% of customers will try a new product orservice from a preferred brand because of theimplied endorsement, credibility, and trust.41

According to Robinette et al.42 of HallmarkCards, Inc, ‘‘increased customer loyalty is thesingle most important driver of long-term profit-

ability.’’ If we look at the lifetime value (LTV) of atop-tier referring doctor whose career spans 35years, revenue generated will easily exceed $1.5million. While calculating LTV is complexbecause of varying costs to acquire and maintaineach customer, there is no doubt that looking atthe ‘‘customer back’’ will allow formulation ofstrategies for each customer segment. Customerloyalty rules!

2. Differentiating your organization from the com-petition: If a customer cannot tell the differencebetween your service and another, they will buyon price. A practice needs to invest in the thingsthat highlight a unique benefit to the customerand deliver it with skill and finesse, like a con-cierge at a fine hotel. Identify and build on thequalities or characteristics which make your prac-tice distinctive.43 Every customer, whether pur-chasing a car, hospital services, or endodonticcare usually has a choice. Your job is to wind upin the referrers’ final consideration set and thenbe chosen because of your unique capabilities. Itcan range from a high-tech approach using a Webbased patient intake process to digital radiogra-phy and microscopic imaging to non-surgicalrevision therapy to diagnosing a difficult case.Remember that technology implementation costsmoney, so do not market your practice as the bestin town and then price it low, because you aresending a mixed message and wasting some ofyour marketing dollars. Learn what characteristics

Customer Satisfaction IndexCustomer Satisfaction Index

0%5%

10%15%20%25%30%35%40%45%50%

1 2 3 4 5completelydissatisfied

completelysatisfied

neutral

Figure 1 Customer Satisfaction Index. In this typical customer satisfac-tion index, completely satisfied customers, rated 5, were six times morelikely to repurchase a product or service over the next 18 months thanjust merely satisfied customers, rated 4.40

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make you office distinctive. If you are going to bea brand, you must be inexorably focused on whatyou do that adds value.

3. Establishing market leadership: First and foremost,communicate that you are a specialist. Make surethat patients understand that you have undergoneextensive post-graduate training. Use verbal andwritten communication to focus attention on con-tinually improving outcomes with the latestscience by using evidence-based treatment thatleads to a painless procedure with the highest levelof success possible. Reveal the hidden by usingmodels, drawings, and microscopic/radiographicimaging to increase the patient’s understandingof the procedure. For example, drawing a scaleddiagram for each patient at the end of their visitwill demonstrate your special skills. Be sure to letpatients know that treatment you perform throughthe microscope is reflected through a mirror, sothat every hand movement is reversed. Use tech-nology to create a value proposition for all stake-holders—defined by modern management scienceas everyone with an interest in what the organiza-tion does, such as clients, employees, and vendors.Demonstrate your proficiency both singly and as ateam, reaffirm the patient’s choice of endodontictreatment over extraction by addressing the bene-fits of decreasing dental disease to improve overallhealth, show sensitivity to patient’s mental andphysical comfort, provide impeccable service, andoffer superb facilities.44

One of the best ways to establish market leadership isto use state-of-the-art technology to create value inthe referrer’s and patient’s mind that they can see andunderstand. Every patient treatment communicationshould reflect your technological competence. Digitalradiographs and photographic images along withcogent narratives of treatment should reflect yourcommitment to the latest technology and help oper-ationalize your brand. Performing a state-of-the-artprocedure and then communicating the results bysending a film-based image and a few handwrittennotes misses the opportunity to maximize your imageas technologically sophisticated. This leads us to thenext section about how to develop brand-buildingprograms that are the most cost efficient, effective,and credible.

There are many ways to help define a brand.Volunteerism and community outreach programsare valuable ways to ‘‘give back’’ and also help yourstakeholders understand your brand philosophy. Thelist of opportunities to partner with other profes-

sionals or community organizations is endless. Hereare a few examples: (1) teaching at a dental school, (2)getting involved in philanthropic and civic organiza-tions, (3) providing continuing education, (4) spon-soring a blood drive with the American Red Cross(Sidebar 2), and (5) partnering with another dentaloffice to benefit a community program like a soupkitchen, food bank, and so on.

USING TECHNOLOGY TOOPERATIONALIZE YOUR BRANDAlthough all endodontic practices provide basic speci-alty services to patients and referring doctors, it is thevalue-added services that can help differentiate yourpractice from competing practices. Research con-tinues to link business success and professionalachievement with developing long-term appeal andcredibility. And adopting proven technologies is oneof the most visible and reliable ways to create a posi-tive impression and to continually engage patients,referrers, and staff, to say nothing of the clinicaladvantages.

Patients expect a high-tech approach to treatment.In fact, the National Health Information Infrastruc-ture (NHII) is establishing a national electronic infor-mation network for heath care. The NHII proposes toimplement a computer-based patient record for mostAmericans by 2014.45 So how will your practice mea-sure up? With the expanding use of technology inevery aspect of life, patients expect their healthcareencounters to include the newest technologies. Use ofthe Internet to improve patient intake, receiving elec-tronic receipt of patient pre-treatment radiographsand information, digital radiography, computerizedcharting, microscopes with imaging capability, instantcommunication of your treatment reports by email,online pharmacology information at the chairside,and music and entertainment options are all ways thatyour office can project a technologically advancedpractice image. The list goes on and on, but theimportance of differentiating your practice cannot beoverestimated, and one of the best ways is with usefuland visible technology.

‘‘A brand strategy is a statement of the brand’ssustainable competitive advantage, usually consistingof a demographic and psychographic description ofthe intended customers and the benefits they get fromthe brand.’’.46 A brand-driven approach will createcustomer loyalty that will ultimately translate into acompetitive advantage and increased profitability.Modern management science defines everyone with

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an interest in what the organization does, such asclients, employees, and vendors are called stake-holders. And each interaction with a stakeholder mustbe understood and prioritized along the entire treat-ment cycle.

How important are employees to the branding pro-cess? The success of any branding strategy depends onengaging employees around your brand in a way thatencourages ownership of the brand. We have allexperienced the exceptional employee who under-stands the brand’s unique character and communi-cates it to all of the practice’s patients, for example,patients, referring doctors, and fellow staff members.Employees who are engaged around the brand con-firm that the patient, referrer, and the brand are thethings to focus on. It facilitates recruiting and reten-

tion of employees and improves morale, aligning eachteam member with your brand promise. All employ-ees need to think, speak, and behave in ways thatcreate the kind of patient and referring doctor experi-ence that has lasting impact. Assimilating your brandamong the employees of your organization will ensurethat all employees understand and embrace yourbrand and can translate this into actionable behavior.This way employees become brand advocates thatunderstand how his or her impact can affect satisfac-tion and ultimately loyalty.

EMPLOYEE MOTIVATION AND MORALEEvery business relies on its organizational values todeliver on its brand promise. Employee attitudes and

OFFICE DESIGN

Appealing to consumer needs has defined marketing for the past one hundred years. According to AbrahamMaslow107 in his book Motivation and Personality, once basic consumer needs like survival and safety aresatisfied, higher order needs like experiential and aesthetic needs become increasingly important. A simplifiedversion of his thesis depicts a pyramid with experiential and aesthetic needs at the top, which leads to the falseconclusion that aesthetics is a luxury that humans care about only when they are wealthy. To the contrary,Virginia Postrel,108 in her book The Substance of Style, states that ‘‘aesthetics is not a luxury, but a universalhuman desire.’’ She contends that humans do not wait for all of their lower order needs to be satisfied beforewanting aesthetic environments and products. She goes on to say that ‘‘there is no pyramid of needs, whereeach layer depends on what we already have,’’ but rather we make important decisions every day based on oursensory experiences. These experiences are based on the precept that appearance counts and that aesthetic valueis real and gaining even more importance in the twenty-first century. According to Postrel, we have entered the‘‘Age of Aesthetics’’ when beauty and style are found everywhere in market economies. Simply put, increasinglysophisticated consumers demand ‘‘an enticing, stimulating, diverse and beautiful world.’’109 To this end, acoordinated and appropriate office aesthetic is important, and color, texture, sounds, lighting, and artwork willall lead to an identity that will satisfy patients experiential and aesthetic needs.

Creating positive attitudes and beliefs about your organization and its services will be influenced by how youdeal with your brand identity. The overall impression of your practice will often depend on the management ofthe themes inherent in individual identity elements that must be coordinated and designed to convey yourbrand characteristics.110 Themes are an expression of your organization’s core values or mission and aretypically created by graphic designers, interior designers, architects, and marketing experts.

The level of finishes you choose should follow a consistent design theme and may include (1) lighting accentfixtures; (2) dry-wall soffits and upgraded ceilings; (3) color balanced walls and carpets; (4) coordinatedartwork and furnishings; and (5) harmonized vinyl, fabrics, and custom finishes. Items that may cause negativevisual impact include (1) showcasing your outside interests; (2) inexpensive furnishings and artwork; (3)unclean and misarranged furniture; and (4) signage that gives information that could be reasonably explainedby the office staff. I hate reception area signs!

When designing or renovating your office, strongly consider what the patient sees and design with them inmind. An office design that resonates with patients is an important factor in establishing a patient’s trust andhelps them measure the quality of your treatment. Design themes should be repeated and coordinated toexpress a close association that increases recall and puts your practice in ‘‘top-of-mind status.’’

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retention rely on a cohesive and upbeat culture. Inorder to develop brand advocates among all of youremployees, your practice must first generate excite-ment about what it does. If each employee under-stands the benefits of modern endodontic treatment,it will reinforce their choice of employment. It canfoster a sense of belonging to a profession they arepassionately proud of. Employees need a leader whoclearly understands the mission of the practice andcan communicate his or her vision to each employee,patient, and referring doctor.

Brand-driven behaviors are enhanced by establishinga strong brand-based culture that is constantly fed andnurtured. It is crucial that your brand commitment isevident from the top down. If employees think that thepractice leadership believes brand building is a priority,they will embrace it with the same passion. Each endo-dontist in the practice must communicate their endor-sement of the practices’ brand vision so that everyemployee experiences appropriate modeling at everylevel of stake holder interaction. Without leadershipsupport and willingness to lead by example, the oldRussian proverb ‘‘the fish always stinks from the headdownwards,’’ will resonate loudly.

Successful brand strategies require a clearly articu-lated vision of what your organization’s brand standsfor and how to link it to your overall business strat-egy. For example, if employees are to bring the brandto life, a strategic foundation must be established. Oneimportant first step is to establish well-defined rolesfor your most important asset—your employees. Thenotion that your patient coordinator can just answerthe phone, assign appointment times, and have cus-tomers fill out forms in the reception area will notlead to a patient-centered practice model that willgenerate a loyal following. There needs to be a con-versation between the patient, referring doctor’soffice, and your staff that is welcoming, informative,and nurturing. It is clear from the work of Silversenand the Werthlen Group that the better prepared apatient is before treatment, the more positive theirtreatment experience will be.47 Of course, our treat-ment must conform to the best available practices ofthe day, but also must provide the key satisfiers of thepatient experience. In Bernick’s48 Harvard BusinessReview article about corporate culture, Alberto-Culverwas able to boost sales 50% by creating a morecustomer-centered approach. It embraced a manage-ment culture that listened to its employees, celebratingevents like birthdays and anniversaries, and creatingpassionate advocates of their brand. Without brandadvocates, your practice will just muddle along, redu-cing the likelihood of reaching your desired future.

BECOMING A LEARNING ORGANIZATIONWhen you go to a barber shop or a salon to get a haircut,you tell the barber or hair stylist exactly how you wantyour hair done. After a few visits to the same person, heor she will probably know just how to shampoo, cut and,blow-dry your hair. You have invested time and energyto tell them how you want it, and they will have likewiseinvested in learning your preferences. In fact, the moreyou tell them about what you want, the more likely youwill revisit the same hair stylist, because, after all, youhave invested in them to create a mutual relationship.We have all experienced this kind of service and will tendto frequent the same establishment time and againbecause they have established a learning relationship. Ifyou were to switch to another barber or stylist, you wouldhave to make that investment all over again. Accordingto Pine et al.49 in an article in the Harvard BusinessReview, customers ‘‘want exactly what they want – when,where and how they want it.’’ And a company thataspires to give customers exactly what they want mustestablish a learning relationship that ensures that allstakeholders collaborate. Developing learning relation-ships with referrers is critically important. The moreyou know about how they want it (new patients sentright over for consultation, one-visit treatment wheneverpossible, etc.), the greater chance that this referrer willcontinue to use your services. If you think about the costof replacing one referrer with another, consider theirlifetime value (LTV). LTV is the sum of the stream ofprofits attributable to this referrer. Take the average valueof referrals in a year and multiply it by the projectednumber of years you intend to practice and you will seehow important each referrer is to the bottom line.

New paradigms of patient care are emerging as therelationship between oral disease and systemic heathbecome clearer. Developing a learning relationship withphysicians is an emerging area that can enhance yourprofessional image with non-dental sources of referral.In order to continually differentiate your practice, con-sider practice-building strategies that incorporate thelatest research in endodontics or health care in general.Liaising with other healthcare providers is a good way topromote improved health and communicate your brandidentity. Study clubs, continuing education opportu-nities, one-on-one meetings, Web sites, and publicationscan create valuable brand advocates.

BRAND ASSIMILATION: PUTTINGTHE PROGRAM INTO ACTIONThe most successful organizations divide brand assimila-tion into three phases: strategic development, foundationbuilding, and implementation. First, develop a strategic

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plan that defines the scope and objectives of your pro-gram so that the right people and systems are identifiedto carry out your program. The second phase is founda-tion building, the process of aligning all employeesaround the central theme of your branding initiativethrough office workshops and reading. This is where eachemployee segment (e.g., chairside assistants and patientcoordinators) learns about your brand initiatives andtheir role in communicating your message. The idea hereis to guide behaviors that foster participation and allowall employees to understand the benefits of your keyobjectives. Implementation, the final phase, is where arange of tactics are employed to create key materials andtalk about successes that will change employee behaviorthroughout the practice. As always, it is important tomonitor the responses to your program and makechanges as necessary.

Establishing a brand assimilation program will leadto a number of changes, but at what cost? How doyou measure success? The first hurdle is to make surethat your employees understand your brand initiative.They have to be invested in developing significantrelationships with your patients. When your employ-ees assimilate your brand, you can begin to imple-ment an action plan that markets your brand. Oneeffective program can be an orientation luncheon fora referring office. Have all of the referrer’s office staffjoin your staff for a catered luncheon, conduct a briefoffice tour, and present a short program to let themknow how you welcome new patients and how goodcommunication between your offices can buildpatient confidence. The practice should strive to high-light the ways that both practices can work together.

Changes in organizational culture do not happenquickly. It takes a considerable amount of leadershipand vision to promote meaningful changes to employeebehavior. But the payoff will be a strong brand that willresonate with patients and referrers and help exciteemployees. This will ultimately result in increased loyalty.

While the detailed application of these disciplines isbeyond the scope of this chapter, it is instructive tolook at the relationship between providing services andrecognizing the link between loyalty and profitability.The service-profit chain provides just such a model foroperating in the medical environment. This is whereleadership develops a dedicated team that providessuperb service to patients that go on to develop loyaltyto your organization.

When customers are highly loyal, there are minimalconsiderations of other brands. In the Xerox studyquoted earlier, a survey of 430,000 customers revealedthat highly satisfied customers were six times morelikely to repurchase a Xerox product than merely

satisfied customers.50 What is the take-home fromthis study? Simply put, the key to business success isto create as many loyal referrers and patients as pos-sible. Then to market your practice in a way that notonly maintains your most loyal referrers and patients,but attempts to increase their ranks by ‘‘marketingbelow the gold.’’ In other words, spend the bulk ofyour energy and precious marketing dollars taking amerely satisfied referrer and elevate them to the extre-mely satisfied category.

What are the benefits of loyalty? Patients willrecommend your office to others. Hearing abouthow great your brand is from someone else will clearlybe much more effective than self-promotion. Loyalpatients are more accepting of new services, will say‘‘no’’ to substitutes, and will pay a premium price foryou to treat them. According to Passikoff,51 over 50%of customers would pay a premium of 20 to 25%before they would switch to another brand. The ben-efits of developing loyal patients cannot be overem-phasized. It takes 7 to 10 times the cost to gain a newcustomer than to keep an existing customer. So dowhatever it takes to retain your current patients.Remember that a service needs to do what is expected,as expected, for as long as expected throughout thecustomer experience.

Build on what differentiates you from the competi-tion. If a patient cannot tell the difference betweenone service and another, they will buy on price. Apractice needs to invest in the things that highlight aunique benefit to the patient and referrer and deliverit with skill and finesse, like a concierge does in a finehotel. After all, patients and referrers really want justtwo things: results and process quality. The results partof the equation applies to a great diagnosis or rootcanal procedure, where the patient feels that he or shereceived caring service and state-of-the-art care andthe referrer feels confident to complete their restora-tion. Process quality is how the referrer and patientwere treated. Was the patient seen on a timely basis?Was the referral handled seamlessly? Was their treat-ment compassionate, respectful, and safe? Did theprocedure make the referring clinician seem likeeveryone was on the same team?

Today’s consumers are increasingly brand-centric,and developing a brand identity is an importantelement in differentiating your services.52 The pro-blem is how to get started so that you can deliveryour brand across every touchpoint and every stake-holder. Begin by formulating a brand strategy thatcreates visibility and recognition, unaided recall, top-of-mind status, deep customer relationships, andbuild differentiation.

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Does this seem impossible? Collins and Porras53 askthe question of how to use words that are not mean-ingless. All McDonald’s corporate strategies are stillguided by Ray Crock, McDonald’s late founder’sacronym, QSVC (Quality, Service, Cleanliness, andValue). Social psychology research indicates that whenpeople publicly espouse a particular point of view,they become more likely to behave in a manner con-sistent with that point of view, even if they did notpreviously hold that belief. ‘‘Passion is a pretty foolproof test of whether a value is a core value,’’ saysMike Moser,54 an advertising and marketing expert.‘‘It will help you include your heart in the decision-making process instead of just your head. Passion iswhat creates an emotional connection that transcendsads, public relations, brochures, or any other craftedmessages that a company puts out.’’

The brand–customer relationship remains one ofthe most underleveraged and yet potentially powerfulways to drive sustainable, profitable, and long-termvalue back to your practice. First, determine yourpractice’s core values. ‘‘Visionary companies tend tohave only a few core values, usually 3 to 6. . .only a fewvalues can be truly core values so fundamental anddeeply held’’ that they will rarely change.55

Every office has a personality, so maximizing thebenefits of your practice by showing genuine warmthand sincere concern for the patient’s comfort are partof a thoughtful brand approach. Simple things likeoffering a warm, moist towel after treatment, provid-ing appropriate music or video entertainment, andalways using the most current technology are criticalto establishing your brand personality.56 Always makesure your brand personality is appropriate for youraudience. Is it predominately male or female, bluecollar, white collar, or service workers? Demographicstudies have shown that endodontic patients are 60%female, average 48 years old, with 69% older than 40years old.57

BRAND TOUCHPOINT OVERVIEWLike most world-class businesses, the best endodonticpractices operate with a clear vision to ensure peakperformance. Just like an Olympic hurdler who men-tally previews his or her performance before an event,from leaving the starting block to breaking the finishline, each element in the patient’s visit must be care-fully planned to ensure that patients feel they are inright place. Every staff member contributes to a suc-cessful visit by interacting with patients in a profes-sional and caring way. It is useful here to visualize thepatient and referring doctor experience as a conti-

nuum that begins with the introduction of endodon-tic therapy and only ends when the patient no longerneeds your services. Dividing these interactions intothree brand life-cycle stages, pre-treatment, treatment,and post-treatment procedures, each interaction canbe choreographed to create a value chain that consis-tently fulfills the patient’s clinical and experientialneeds. These steps are really brand touchpoints, orthe different ways your services interact with patients,referrers, and fellow staff members. The members ofyour staff have to serve as brand ambassadors, andeach interaction with patients and referring doctorsmust be consistent to ensure the best experience.

In order to be truly successful, every functional areain your organization must be responsible for bringingthe brand promise to life. There must be total align-ment between your organization and your brandstrategy, so that you control the critical interactionsyour patients and referrers, or stakeholders, have withyour brand. What are all the touchpoints that existbetween your brand and a current or potential stake-holder? How can you create a brand-driven organiza-tion? Outlined below are 10 brand touchpoints com-monly found in endodontic practices. Please note thatonly 5 of the 10 involve the practitioner, and only oneof these involves the practitioner alone. The impor-tance of selecting an outstanding staff and takingcontrol of all patient and referring doctor touchpointscannot be overemphasized.

1. Patient is informed that they need endodontictreatment: The process begins when the patientis advised that he or she needs an endodonticconsultation. Providing each referrer with a kitthat contains your office brochure, referral forms,appointment cards, business reply envelopes, andWeb site information will help introduce patientsto your practice. According to Jack Silversin,58 inhis American Association of Endodontists-fundedstudy to learn about the endodontist–patient rela-tionship, the more your patients know about theirtreatment in advance, the better their treatmentexperience will be.

2. Patient calls for their first appointment: When anew patient calls for an appointment, complete awritten telephone intake form or software-basedpre-registration form, and set up an initial appoint-ment. The telephone intake form should bedesigned with a sequenced set of questions in orderto get efficiently critical information and documentthat all pre-treatment instructions were given.

Telephones are an essential part of the new patientexperience, so make sure that proper telephone etiquette

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is practiced at all times. According to Albert Mehra-bian,59 a pioneer in communications research, there arethree elements to any face-to-face communication:words, tone of voice, and body language. When it comesto feelings and attitudes, approximately 7% of meaning isin the words that are spoken, 38% of meaning is para-linguistic (the way that the words are said, like smiling onthe phone), and 55% of meaning is in facial expression.The telephone creates an immediate communication gapbecause facial expression is not apparent, so the wordsand paralinguistic attributes take on added importance.

New patients should be queried about their status,because patients in pain and/or swelling are interestedin immediate treatment and will generally accept sche-duling at the convenience of the office. These patientswill ideally need to be appointed the same day they call.Patients who have no discomfort or mild discomfortwill generally be interested in convenience.

There are several methods available to providepre-treatment information. Invite new patients toview your office Web site, where they can completea secure patient registration and health history form.Web sites are necessary, if not a necessity, in today’shealthcare environment. According to Harris Inter-active, in a poll of 1,015 US adults conducted in2005, 72% search the Internet for health-relatedinformation.60 Almost 58% report looking for infor-mation often search the Internet for health topicsand only 14% say that they hardly ever search healthtopics. Even more remarkable, 85% of those whohave ever searched the Internet for health-relatedinformation did so in the last month of the study,and now averages seven searches each month perpatient. What does this mean to the endodonticpractitioner? Today, patients expect to meet theirprospective practitioner on the Internet. Mailing,faxing, or emailing a ‘‘welcome kit’’ to patients witha welcome letter, brochure, procedure explanation,doctor biography, financial policy, registration,health history form, and map are also valuable waysto streamline new patient intake. Creating a Web site toprovide patient education opportunities, contact infor-mation, and referral materials will further enhance pre-treatment preparation and provide the most convenientand cost-effective solution. While society is becomingmore accustomed to automation and the advantages itprovides, ‘‘dentists must be careful not to allow tech-nology to interfere with the relationship between patientand doctor and the patient and staff.’’61

If the office must meet the requirements of HIPAA,all online transactions, as well as the office network,must be secure. If the office uses a wireless network,appropriate security measures are required.62

3. Patient arrives for first visit: When patients arrivefor their initial visit, be prepared and give them awarm and sincere welcome. Patients can completetheir registration on a reception area computerkiosk connected to the practice’s network or theInternet, or fill out paper-based forms and vieweducational materials while in the reception area.This is the time for scanning any film-basedradiographs or appending digitally transmittedimages into your radiographic database, if applic-able. Some endodontic software can allow frontoffice personnel to indicate the patient’s statusfrom their arrival at the office and transitioningthrough treatment and finally discharge. Besidesdepicting the status of each patient in the office,recording the chair time for each type of proce-dure will allow create metrics that can be used tomeasure profitability.

4. Patient is escorted to operatory: Escorting patients tothe operatory is an opportunity to connect staff andpatient. Employee name badges and a policy of eachstaff member introducing himself or herself to thepatient by name should be practiced at all times.Also, chance encounters in the office where a patientis within five feet should prompt a ‘‘hello’’ greeting.

When the patient is seated in the dental chair, thepatient’s individual record should appear on the chair-side computer screen in the operatory, maintainingHIPAA compliance, and assuring the patient that yourefforts will be focused on them. Once seated, the assis-tant should confirm that the patient has followed allpre-treatment instructions, including their antibioticpre-medication regimen if any, other pre-treatmentmedications, and have eaten breakfast or lunch toensure a normal blood glucose level, whichever isappropriate. Of course, staff should confirm that allprescribed medications have been taken on schedule,and if sedation is contemplated, an escort is present toaccompany the patient after treatment completion. Thisis the time for your staff to tell the patient what comesnext and set their expectations for their visit. Assuringthat their comfort is of utmost importance, offering ablanket or pillow, describing what treatment will beperformed, length of the visit, and so on are all impor-tant. Acknowledge and reassure the patient that his or herconcerns will be addressed. This is also the time to projecta safe practice image. Sanitize your hands in front of thepatient or let them know you are leaving the operatory towash. Wear proper clothing and limit masks, gloves, andother protective gear to the clinical areas of the office. It isincumbent on the endodontic practitioner to convey asense of safety throughout each visit.63

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This is the time for the dental auxiliary to recordthe chief complaint, history of present illness, medicalhistory and review all current medications. Once thegeneral area of interest is determined, the auxiliaryshould expose dental radiographs, record photo-graphic images, take vital signs, answer questions,and, most importantly, comfort the patient. Each staffmember should be dressed and groomed appropri-ately, scripted for this interaction, with the bestanswers to commonly asked questions to promoteconsistency and accuracy. Of course, all medicationsshould be recorded in the patient’s database so newprescriptions can be automatically checked foradvised interactions and cautions.

5. Doctor consults with patient: After introductionby the dental assistant, you should establish eyecontact, make sure the patient is comfortable, lis-ten attentively without interrupting, and accordingto MaryJo Ludwig64 Clinical Faculty, Depart-ment of Family Medicine at the University ofWashington Hospital, ‘‘acknowledge and legiti-mize feelings, explain and reassure during exam-inations, and ask explicitly if there are other areasof concern.’’ First impressions are important, andyour first contact with the patient is no exception.Psychiatrists Leonard and Natalie Zunin,65 statedin their book ‘‘Contact: The First Four Minutes,’’that, on average, there is only a short moment intime, a 4-minute window, ‘‘to grab someone’sattention and establish credibility and rapport.’’These first impressions demonstrate our compas-sion, care, intelligence, attention to detail, andpride. Be sure to limit the time you spend withthe computer at the expense of eye contact andpersonal interaction with the patient. Once thepatient’s dental needs and intake data arereviewed, the initial oral exam is completed, adiscussion and informed consent can take place.According to Peter Sfikas,66 chief legal counsel ofthe ADA, the ADA’s Code of Professional Conductrequires dentists to ‘‘inform patients of proposedtreatment and any reasonable alternatives in amanner that allows the patient to become involvedin the treatment decision.’’ Every dentist shouldunderstand the requirements of their state practicelaws with regard to informed consent. In thisregard, states differ greatly. In Pennsylvania, forexample, a court ruling held that orthograde endo-dontic treatment was a surgical procedure requir-ing written informed consent, while treatmentconsidered non-surgical in nature does not requireinformed consent. Conversely, courts in New Jer-

sey require dentists to provide informed consenteven for non-invasive procedures. Also, a patient’srefusal of recommended treatment should bedocumented in writing to ensure that the patientcomprehends the possible consequences of refus-ing treatment. After the discussion and informedconsent processes are completed, any additionalpre-operative issues should addressed. Any patientwho has not eaten a timely meal and will receivelocal anesthetic should receive an appropriatenutrient supplement to avoid syncope from lowblood glucose levels. Ensure� and Glucerna� arelactose-free drinks designed for occasional mealreplacement and intended for non-diabetic anddiabetic patients, respectively. If non-steroidalanti-inflammatory drugs or antibiotics are indi-cated, they can be dispensed at this time.

6. Doctor treats patient: Every effort should be madeto include the patient in the treatment process.Confirm that all of the patient’s questions areanswered. Then treatment can be initiated alongwith documentation of the visit. If digital schedul-ing is available, patients can be reappointed whilestill in the operatory and their insurance informa-tion can be sent to the office financial coordinatorvia the network or directly to the insurance com-pany, if the office LAN integrates with the Internet.

7. Doctor discharges patient: Once the treatment iscompleted, the final 4 minutes should focus onthe patient and their post-operative instructions.Communicate that you are a specialist by drawinga scaled diagram for each patient at the end oftheir visit that explains the intricacy of your pro-cedures. Use technology to create a value propo-sition for all patients. In the end, be sure to takeevery opportunity to complement the patient ontheir cooperative attitude. Medications can nowbe dispensed, as necessary, and prescriptionsselected and sent to the printer.

8. Patient is escorted to front desk: Patients are thenescorted to the office departure station and rein-troduced by their escorting assistant to the patientcoordinator. Sit-down departure stations at thefront desk will serve to increase patient comfortand to better accommodate disabled patients. Insome endodontic offices, advanced practice man-agement software will allow the clinician or assist-ing staff to forward all pertinent billing state-ments and post-operative instructions to thefront desk computer with a few mouse clicks.

9. Patient is checked out: Once the patient is broughtto the departure station, they are asked the ‘‘1, 2, 3questions’’: (1) The patient coordinator asks the

Chapter 41 / Operations Management in Endodontic Practice / 1493

patient how they are feeling; (2) Next, the patientreceives customized instructions, which outlinetheir post-operative instructions and an explana-tion of check-up recommendations. Patients arethen appointed for their next visit and receive anyprescriptions and a patient satisfaction survey witha business reply form centered on the reverse sidefor mailing convenience; (3) Lastly, patients areasked to satisfy their financial obligation.

A business reply permit can be obtained from yourlocal post office at a nominal cost. Patients can eitherfill out the form immediately (highest response rate)or return it by mail. If patients are invited to fill outthe form in the office, a box should be available for thecompleted survey. Because people often feel awkwardexpressing their real views, this anonymity willimprove compliance.

Measuring patient satisfaction will provide twomain benefits: (1) it will allow patients to vent aboutissues that will ultimately affect their loyalty and theirlikelihood to return for additional treatment, and (2)surveys present valuable feedback about what reallyworks and what doesn’t. All too often, we are provid-ing what we want to and not what the patient deeplyvalues. In a recent 2-year examination linking custo-mer satisfaction with purchasing behavior, and ulti-mately with company growth, Reichheld67 concludedthat the likelihood of a customer recommending yourservices to a colleague or friend was directly related toincreased growth.

Patient treatment reports and other correspon-dence can be created by the front desk or assistingstaff, reviewed by the practitioner, and then trans-mitted to a printer and/or email client for distributionto referrers. It is important for the patient to list all oftheir co-therapists during registration, so they willautomatically receive the final treatment reports.

10. Doctor telephones patient in evening: The lasttouchpoint is the evening phone call by thepractitioner to the patient. The value of this callcannot be overemphasized, as it is one of themost appreciated services reported by patientson their satisfaction surveys.

Remember that patients want to be treated in aclean and welcoming office environment. They evalu-ate your office on a continual basis, and educatingyour patients about the safety precautions you takewill add value. Always assure patients that their com-fort and safety are major objectives of their treatment.Try to explain the procedure, with permission, to thepatient in terms they can understand. Use everyopportunity to further establish your technological

leadership by making them a partner in their treat-ment. The relevance of your brand involves reversethinking. You need to ‘‘move out of your world andinto theirs.’’68 It is not what you are selling; it is whatthey are buying, that counts!

DEVELOPING A CULTURE OFEXCELLENCE AROUND YOUR BRANDThe operation of the practice can be managed byasking a key question: How can I be excellent? Andthe answer is by designing systems that allow you todo the job right the first time. Creating a strategy toachieve success requires five basic steps, each depen-dent on the preceding step to accomplish your goals.

1. Step 1: Identify which patients you really want.Begin with a clear understanding of who yourpatients are and which ones you want to serve.

2. Step 2: Identify what your targeted referrers andpatients deeply value. All purchasers of services orproducts want results and process quality. Finish-ing treatment with a pain-free and fully function-ing tooth is the results part. And having a positiveexperience where respect, timeliness, courtesy andtreatment with all needs (in the mind of thepatient or referrer) met on a consistent basis isthe process quality part of the equation.

3. Step 3: Develop a ‘‘customer-centered focus.’’Learn to manage the convergence between whatyour patients deeply value and the things that youdo best. This means that the core procedures areperformed in a caring and expert manner. Focuson the routine procedures that lend themselves tothe highest levels of success with the most profit.

4. Step 4: Make ‘‘creating a customer-centered focus’’your mission. Your mission is your ‘‘compass’’ inan increasingly challenging practice environment.This means understanding your mission and howeach stakeholder will support and interact with themission. Everyone needs a program that they canown, but be ready to change on a routine basis.

5. Step 5: Create an organization-wide obsession withyour mission. To become consistent and successful,communicate your mission to your staff, yourreferring doctors, and patients.69 In fact, brandsdemand consistency. According to Straine andStraine,70 ‘‘If your receptionist is rude, if your officemanager is unhelpful when a patient needs finan-cing, if your policies are always changing, the nega-tive impact on your brand’’ will destroy your effortsto achieve clinical excellence.

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‘‘QUALITY IN FACT’’ AND ‘‘QUALITYIN KIND’’Another important concept that will help theempathize with patients and referring doctors is theconcept of treatment quality as viewed from thepatient perspective. In a look at quality, former Mal-colm Baldridge Award examiner Patrick Townsend71

defines quality in fact as goods or services that mea-sure up to the specifications of the provider. Forexample, when an endodontic procedure is com-pleted, does it meet all of the desired specificationsas defined by the practitioner? Are all of the canalsidentified, cleaned, shaped, and obturated to comple-tely seal the root canal system? If so, then the proce-dure meets the specifications of the provider andsatisfies the criteria of a satisfactory case. But that isonly half of the story. The other half is defined by theauthors as quality in kind, or the way that the patientperceives the procedure—from their viewpoint. Forpatients, a successful visit will hinge on how thepatient was treated, because the success of the proce-dure will be judged on the subjective quality as thepatient sees it, or the experiential aspects of theirvisit. And do not short change the importance ofthe physical environment of the office. If the officelooks tired, patients will respond in kind, becausepatients will ‘‘judge the book by its cover.’’ There isno way for most customers to even begin to assessthe quality of the endodontic treatment they receive,they can only judge by how they were treated, theappearance of the office, and other non-technicalaspects of their treatment. Take a quick mental jour-ney through your office, reception area, front deskarea, hallways, sterilization area, and operatories. Dothey reflect your intended practice image? Are theymodern, clean, efficient, organized, and calm? Does itsend the message that your practice is up-to-date?Pay attention to the details—your patients and refer-rers are. Remember, you do not get a second chanceto make a great first impression.

UNDERSTANDING SATISFACTIONA typical business customer satisfaction index isshown in Figure 1. If the satisfied and completelysatisfied patients total 81%, should the directors ofthis company be content? Should a business concen-trate its resources on increasing the satisfaction of thevery dissatisfied patients or try to raise the merelysatisfied customer to a completely satisfied level?

Studies have shown that it is far cheaper to raise thecustomer with a satisfaction index of from between 3.5and 4.5 to a 5 than move a very dissatisfied customer

to a higher level.72 Many businesses spend a dispro-portionate amount of resources on a small percentageof customers who are almost impossible to please.Pursuing these customers also may hurt companymorale and will disparage the company to otherpotential patients.

What impact will this have on an endodontic prac-tice? Referring doctors and patients who enjoy completesatisfaction with your services are more likely to be loyal‘‘apostles’’ of the office than those who are just satisfied.

Professor James Hasket73 of the Harvard BusinessSchool, in his ground-breaking research on the ‘‘satis-faction-loyalty link,’’ states that ‘‘if employee perfor-mance and loyalty is good within an organization,then that organization’s customers will be more likelyto repurchase a product or service.’’ One way tomeasure the satisfaction of your referring doctorsand customers is to use a satisfaction survey. Thistool, outlined in more detail above, can point outareas that you can improve, such as front desk opera-tions, office hours, parking, and so on.

Once you have identified areas that need correctiveaction, be prepared to create an action plan to fix theproblem. Remember, a problem exists if a referringdoctor or a patient perceives a problem. Problems canbe fixed and loyalty maintained if the problem is fixedquickly. It has been shown that 95% of customers willrepurchase a product or service if the problem is fixedon the spot, and 78% of customers will repurchase ifthe problem is fixed within 24 hours.

Every patient and referring doctor should receive thebasic elements they expect, like a professionally perfo-rmed and technologically advanced procedure. Every-one receives the basic support services that includeinstructions, assistance with financial arrangements,and insurance filing. Everyone gets the basic recoveryhelp that includes an apology for an appointment delayor correction of a billing error. But only certain refer-rers will get extraordinary services that excel in meetingtheir personal preference that make the service seemcustomized. An example of the extraordinary servicesyou might provide to a core referrer might be treating apatient for his or her convenience on a Saturday fornon-emergent treatment when you normally do notconduct business on a weekend.

PATIENT SATISFACTION SURVEYSPatient questionnaires seek explicit information thatcan be analyzed and trended over time. Patient opi-nion surveys can help determine satisfaction withoffice personnel, procedures, or other aspects of thepractice which may ultimately affect patient and

Chapter 41 / Operations Management in Endodontic Practice / 1495

referring doctor loyalty. Opinion surveys can be cus-tomized to fit the needs of each practice and allowcustomers to vent if there are problems.

Several options are available, each of which can beintegrated into broader Total Quality Management(TQM) initiatives or performance assessment strategies.Surveys can be short in-office questionnaires, with eachpatient filling out a form while in the office, or longertake-home questionnaires. Anonymity may promptpatients to be more honest with their feedback. If iden-tity is disclosed, the surveys can include call-backs topatients after they have returned home. They can eveninvolve focus groups to investigate very specific ques-tions about programs, services, and staff. Other forms ofsurveys include mail and email surveys, sent to a ran-dom selection of patients. These survey channels maygive the patient more time to complete the survey,which may result in a more in-depth response.

The most personal way to conduct a satisfactionsurvey is in person or by telephone. You can have astaff member or research professional perform thesurvey. Patients can more easily elaborate on theirresponses, but these types of surveys can be expensive.

In recent research published by Press Ganey Associ-ates74 to evaluate heathcare satisfaction, patients ratedthe courtesy, friendliness, and professionalism of thedental assistant as more important than that of thedentist! Infection control and cleanliness was ratedsecond. While the dentist’s skill was important, thedentist’s attention to patient anxiety and concernswere directly related to patient loyalty and theirpotential to refer other patients. Patients also ratedthe amount of time spent with a patient and explana-tion of treatment options as important indicators ofpractice quality.

Installation of a bulletin board at your office toallow clinicians and staff to read each survey is aneasy way to share comments and build a consensus.Many surveys reinforce employee behavior, especiallyif they mention a staff member by name. Each surveyis an opportunity for your organization to improve.

CREATING A WEB SITE, STATIONARY,AND BROCHUREOne of the most often neglected parts of an officebranding program is the production of Internetresources and coordinated office publications. Internettechnology is advancing at a record pace. In everyfield, including dentistry, entrepreneurs are using itto devise new and better ways to develop businessand lower costs. To ensure brand awareness in the

future, endodontists must acknowledge the enormouspotential of this technology and develop sound strate-gies for harnessing all its capabilities. In the largercontext, an Internet site can be part of your overallidentity management program that ties together allmarketing materials to communicate your practicesvision. Using a professional design firm to create yourWeb site, stationary, and brochures will ensure a coor-dinated look that will be more powerful thanunmatched pieces. Internet technology can enableyour practice to broaden the scope of patient relationsand increase communications with patients, referringdoctors, and study clubs. Over the last few years, theInternet has become a unique medium for the endo-dontist to promote innovative and technically sophis-ticated treatment.

Getting started on a Web site can be a challengingbecause there is a tendency to keep changing, and thepossibilities are virtually limitless. Here are somepointers to help you get started:

1. The best way to begin is to visit other medical anddental provider’s Web sites. Learn how to navigatetheir site, what elements are required and if you wantto include programs with more high-end graphiceffects. Simple is better, but patients and referringdoctors will want to see some ‘‘eye candy’’ and learnon each visit. Video segments featuring you and yourstaff are becoming more commonplace as videotechnology over the Internet improves.

2. Decide on your goals. Is it to generate referrals viaInternet search engines, develop links to sites thatmarket dentists, or serve as a resource for yourpatients and referring doctors?

3. Work with Web site professionals to create adesign for your site. Remember that the designof the site should complement the image you aretrying to project. Also, consider employing searchengine optimization techniques to make your sitemore prominent.

4. Outline your proposed site and create a story-board that includes navigation possibilities foryour audience. Design every page on a separatepiece of paper and test your ideas with friends,selected patients, and referring doctors.

5. Choose a Uniform Resource Locator (URL) sothat Internet address can be easily rememberedand entered in a browser with a minimum ofeffort and confusion. The URL should tie intoyour desired image.

6. Then just fill in the blanks with copy, photo-graphs, and an appealing style that projects yourvision. Keep it fresh. If you want repeat visitors,

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continually update the site and make sure yourlinks are relevant and functional.

Human Resources

Organizational success in endodontic practice requiresa high-performance staff.75 After all, your employeesare your brand. They must understand what yourbrand stands for and how to deliver on your brandpromise. Pfeffer and Veiga76 observe that ‘‘there is asubstantial and rapidly expanding body of evidence,some of it quite methodologically sophisticated, thatspeaks to the strong connection between how firmsmanage their people and the economic resultsachieved.’’ Exactly how important is marinating awell-trained and dedicated staff? Recent studies lookedat 968 firms representing all major industries and foundthat just a 7% decrease in employee turnover resulted ina per employee increase of $27,044 more in sales and$18,641 more in market value.77 It is clear that anybusiness, including an endodontic practice, can benefitby adopting employee-related best practices to ensurefinancial success and ultimately clinical excellence.

According to Pfeffer and Veiga,78 the most importantelements of a successful HR management program are(1) providing long-term job security to assure thatemployee efforts will be rewarded; (2) recruiting andhiring the right people from the beginning; (3) creatingself-managed project teams of peers to increase theirsense of responsibility and accountability; (4) providinghigh compensation that is contingent on performance;(5) investing in extensive training for all employees; (6)reducing status differences between employees toimprove idea generation from all employees; and (7)teaching information sharing to create a high-trustorganization that allows inclusiveness.

JOB DESCRIPTIONThe largest cost items for most endodontic practices isemployee wages and benefits.79 The plethora of reg-ulations, such as equal employment opportunity(EEO) legislation enacted by local, state, and federalgovernments, has made job analysis a mandatory partof HR management. One of the most useful productsof comprehensive job analysis is the job description,an Americans with Disability Act (AwDA) compliantnarrative of the major responsibilities and duties asso-ciated with each job. While most job descriptions arelimited to a single type of service or project, manyendodontic offices require the use of cross-functionalteam members to complete certain tasks or to fill-infor a vacationing employee.

A good starting point is to consult O*NET, a USDepartment of Labor (DOL)-sponsored comprehen-sive source for continually updated information onoccupational characteristics. Based on the most cur-rent version of the Standard Occupational Classifica-tion System, each O*NET occupational title and codeincludes descriptors for skills, abilities, knowledge,tasks, work activities, work context, experience levelsrequired, job interests, and work values.80 A partialsample of O*NET’s listed tasks, knowledge, and abil-ities section for dental assistants (code 31-9091.00) aresummarized in Table 3.

THE STANDARD OPERATING PROCEDUREOften overlooked but extremely valuable, the standardoperating procedure (SOP) is a written practices andprocedures reference, which is designed to ensure thatkey procedures are performed in a safe and compliantmanner. The SOP is typically written by the currentjob holder and edited by the practice administrator.81

SOPs force employees to think through a procedure

Chapter 41 / Operations Management in Endodontic Practice / 1497

Table 3 Tasks, Knowledge, and Ability Tasks

Importance Category Tasks

99 Core Prepare patient, sterilize and disinfect instruments, set up instrument trays, prepare

materials, and assist dentist during dental procedures

92 Core Expose dental diagnostic X-rays (certification may be required)

90 Core Record treatment information in patient records

88 Core Take and record medical and dental histories and vital signs of patients

88 Core Provide post-operative instructions prescribed by dentist

87 Core Assist dentist in management of medical and dental emergencies

77 Core Instruct patients in oral hygiene and plaque control programs

79 Supplemental Apply protective coating of fluoride to teeth

76 Supplemental Schedule appointments, prepare bills and receive payment for dental services, complete

insurance forms, and maintain records, manually or using computer

Importance Knowledge

87 Medicine and Dentistry—Knowledge of the information and techniques needed to diagnose and treat human injuries,

diseases, and deformities. This includes symptoms, treatment alternatives, drug properties and interactions, and preventive

healthcare measures

73 Customer and Personal Service—Knowledge of principles and processes for providing customer and personal services.

This includes customer needs assessment, meeting quality standards for services, and evaluation of customer satisfaction

64 English Language—Knowledge of the structure and content of the English language including the meaning and spelling of

words, rules of composition, and grammar

59 Clerical—Knowledge of administrative and clerical procedures and systems such as word processing, managing files and

records, stenography and transcription, designing forms, and other office procedures and terminology

51 Chemistry—Knowledge of the chemical composition, structure, and properties of substances and of the chemical

processes and transformations that they undergo. This includes uses of chemicals and their interactions, danger signs,

production techniques, and disposal methods

42 Computers and Electronics—Knowledge of circuit boards, processors, chips, electronic equipment, and computer hardware

and software, including applications and programming

40 Psychology—Knowledge of human behavior and performance; individual differences in ability, personality, and interests;

learning and motivation; psychological research methods; and the assessment and treatment of behavioral and affective

disorders

40 Public Safety and Security—Knowledge of relevant equipment, policies, procedures, and strategies to promote effective

local, state, or national security operations for the protection of people, data, property, and institutions

36 Mechanical—Knowledge of machines and tools, including their designs, uses, repair, and maintenance

Importance Ability

78 Oral Expression—The ability to communicate information and ideas in speaking so others will understand

75 Oral Comprehension—The ability to listen to and understand information and ideas presented through spoken words and

sentences

72 Near Vision—The ability to see details at close range (within a few feet of the observer)

72 Written Expression—The ability to communicate information and ideas in writing so others will understand

66 Information Ordering—The ability to arrange things or actions in a certain order or pattern according to a specific rule or

set of rules (e.g., patterns of numbers, letters, words, pictures, and mathematical operations)

66 Speech Clarity—The ability to speak clearly so others can understand you

62 Arm-Hand Steadiness—The ability to keep your hand and arm steady while moving your arm or while holding your arm

and hand in one position

60 Speech Recognition—The ability to identify and understand the speech of another person

56 Finger Dexterity—The ability to make precisely coordinated movements of the fingers of one or both hands to grasp,

manipulate, or assemble very small objects

56 Problem Sensitivity—The ability to tell when something is wrong or is likely to go wrong. It does not involve solving the

problem, only recognizing there is a problem

56 Selective Attention—The ability to concentrate on a task over a period of time without being distracted

56 Written Comprehension—The ability to read and understand information and ideas presented in writing

53 Flexibility of Closure—The ability to identify or detect a known pattern (a figure, object, word, or sound) that is hidden in

other distracting material

53 Manual Dexterity—The ability to quickly move your hand, your hand together with your arm, or your two hands to grasp,

manipulate, or assemble objects

Table 3 continued on page 1499

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step by step and are in themselves useful trainingtools. More complex tasks lend themselves to theSOP structure for training new employees and mod-ifying procedures to improve efficiency and safety.While SOPs work well for procedures that requiresafety and standardization, they may limit creativitywhere imagination is warranted. The best approach isto be concise and make the document as dynamic aspossible. SOPs should be easily accessible to allemployees via the practice’s computer network andat a minimum should be updated on an annual basis.

Each SOP should have a header with the title,original issue date, revision dates, number of pages,the author of the SOP, and ‘‘approved by’’ signatureplus the following basic elements (Table 4):

1. Desired outcome2. Definitions3. Measurement4. General information5. Step-by-step procedure with identification of cri-

tical information6. Attachments and forms to be used, if any

CREATING THE EMPLOYEE HANDBOOKEmployee handbooks help to establish the employer’sexpectations and can prevent misunderstandings thatmay reduce the risk of litigation. Because most employ-ees want to be successful, they will generally welcome adescription of expectations, procedures for obtaining apromotion or raise, policies on dress, leave requests,work hours, disciplinary issues, and other importantguidelines. The process involved in creating a handbookcan also help you think through and establish your ownunique policies. To aid in the process, consider getting

professional advice from your attorney, accountant, or apersonnel advisory firm, so that personnel proceduresare documented before contentious issues arise. Person-nel advisory firms can provide comprehensive and cost-effective help and implementation, providing excellenthandbooks, supporting resource manuals, and technicalassistance. The ADA also sells a hand-book resourcemanual with step-by-step guidance.

Courts generally view both verbal and written policiesas a contract. However, unwritten policies may posemore risk than written policies, because verbal policieseither can be implied or given by someone with noauthority. Written handbooks help avoid conflict byreducing the chances of a dispute between you andemployee, especially in the most litigious areas of firingand discipline. It is critical that your handbook is prop-erly vetted by knowledgeable advisors, because, as PeterSfikas,82 ADA general council notes, courts ‘‘have deter-mined that manuals, handbooks and booklets can createimplied employment contracts, subjecting the employerand employee to additional terms and conditions ofemployment.’’ In the interest of both the employerand the employee, written handbooks that clearly statethe policies of the practice serve to minimize the risk oflitigation, and well-drafted disclaimers may help tomaintain the ‘‘at will’’ status of employees. Generally, aclear statement at the beginning of the handbook statingthat the handbook is not a contract and that the policiestherein can change at any time without advanced noticewill provide some measure of protection.

According to the U.S. SBA,83 an employee hand-book should include the following:

1. Overview of practice philosophy and history2. Equal opportunity statement that hiring, promo-

tion, pay, and benefits are not related to employee’s

Table 3 continued from page 1498

53 Time Sharing—The ability to shift back and forth between two or more activities or sources of information (such as

speech, sounds, touch, or other sources)

50 Category Flexibility — The ability to generate or use different sets of rules for combining or grouping things in different ways

50 Control Precision—The ability to quickly and repeatedly adjust the controls of a machine or a vehicle to exact positions

50 Deductive Reasoning—The ability to apply general rules to specific problems to produce answers that make sense

National wage and employment trends

Category Occupation information

Employment (2004) 267,000 employees

Projected growth (2004–2014) Much faster than average (36+ %)

Projected need (2004–2014) 189,000 additional employees

A partial list of the tasks, knowledge, and ability associated with dental assisting is reproduced above. Adapted from O*NET Web site http://online.onetcenter.org/link/

details/31-9091.00, accessed May 1, 2007. O*NET is a service of the U.S. Department of Labor and acts as a comprehensive source of ranked descriptors for more than

900 occupations.

Chapter 41 / Operations Management in Endodontic Practice / 1499

race, color, religion, sex, age, disability, or nationalorigin.

3. Work hours should be defined, including time forlunch and conditions that could require latehours, such as treating after-hours emergencies.

4. Wage policies should include general informationabout when paychecks will be issued, how andwhen promotions are handled, classification ofpart-time, full–time, and on-call employees, over-time, loans, and leaves without pay.

5. The performance review section should describehow and when employees will be evaluated;unscheduled evaluations may be made at any

time to advise employees of unsatisfactorywork.

6. Paid holidays and all types of leave, includingfamily (maternity, adoption, and elder care), med-ical, dental, funeral, personal, jury, and militaryshould be listed.

7. A termination section should inform employeesabout causes that will trigger firing, includingcriminal activity, insubordination, absenteeism,and poor work performance.

8. All forms should be included, such as samplerequests for vacation, medical leave, hepatitis vac-cination declination, and so on.

Table 4 Standard Operating Procedures: Computers

Desired Outcome: All computer equipment in the Practice will operate efficiently to create and store all radiographic and visible light images, clinical charts, patient

financial transactions, appointments, protected health information (PHI), and other materials related to the Practice. Patient confidentiality will be maintained in

accordance with the Practice’s current Health Insurance Portability, and Accountability Act (HIPAA) Manual and office policies.

Definitions: Information technology (IT) refers to the use of computers and computer software to manage office information.

Measurement: Evaluation of internal and external customer satisfaction by ‘‘Employee Evaluation of Office’’ and ‘‘Patient Satisfaction Survey.’’ Internal customers will

experience infrequent computer down time, undergo adequate training, and use programs that do the intended job right the first time.

Introduction: All computer systems in the office are critical to the success of the Practice. The Practice stores all clinical and administrative data on the office computer

system. Therefore, the Practice’s computers and networks are to be used for Practice-related work only.

No expectation of privacy: In the course of operation and maintenance activities, use of computers and networks may be monitored to ensure the continuing

effectiveness and integrity of the Practice’s IT resources. Email, Web logs and data, and other files created or received while using the Practice’s computers are neither

private nor confidential. The Practice reserves the right to access and disclose all messages sent by its computers and networks, as well as any data created, received,

or stored on them.

Computer security and access to files and email: Although the Practice intends to convey no expectation of privacy, its business communications must be protected from

unauthorized access. At no time may any employee remove or transfer any data to computers outside of the office by any means, including disks, jump-drives, CD-ROMs,

or the Internet for any reason.

Employees are not to give any computer information to anyone on the telephone who calls our office without specific permission from Dr. Levin or Dr. Lee. The only

exception is our IT services company.

No disks, CD-ROMS, or other material of any kind can be brought from the home of an employee and placed on the Practice’s computer systems at any time.

Patient confidentiality: see HIPAA Manual and office policies as published periodically.

Internet use: No employee is allowed to use the computer system for personal use at any time.

Web: When using the Web, only the approved Internet browser is permitted. Approved sites include only those directly related to the business of the Practice.

Email: Only MS Outlook, Google, and Yahoo are approved for email use. Any email messages generated or viewed at the office are the property of the

Practice.

Virus protection: We use McAfee Enterprise virus protection, which automatically updates all of our workstations every night via the McAfee Web site and our LAN. All

computers will be running McAfee virus protection at all times. This will protect our system from virus destruction and other potentially harmful computer intrusions.

Confirm that this software is active at start-up and remains active at all times.

Firewall protection: We are protected from hackers through our Internet switch called WatchGuard ‘‘Firebox.’’ Make sure this equipment is on at all times.

Backup: We use a tape backup system, located in the server. Each business day, a numbered tape is placed in the server and noted on the ‘‘Backup Log’’ by the

operator’s initials. Every Friday, the cleaning tape is placed in the tape drive, allowed to complete one cycle that takes approximately 1 minute, and is removed from the

drive. On Monday, the Friday night tape is placed on Dr. Levin’s laptop bag for off-site storage.

Passwords: Each employee will be issued a discrete user name and password to log into EndoVision. As there are nine levels of security, some codes will not allow

every user to perform all tasks.

SQL: EndoVision (EV) and Schick (CDR) use their own database engines that reside on the server. This SQL database software must be active on the server to allow

workstation access to EV and CDR. Both of these SQL database engines will be running on the ‘‘Taskbar’’ of the server. If you cannot login from any workstation for

either EV or CDR, check the server to see if their individual SQL database engines (icons in the taskbar) are active.

PC software and hardware controls: Users may not download, purchase, or install software or hardware on office computers unless it is approved by Dr. Levin or Dr. Lee

Copyrighted and licensed materials may not be used on a PC or the Internet unless legally owned or otherwise in compliance with intellectual property laws.

Critical information is italicized.

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9. Acknowledgement of receipt and reading ofhandbook by employees should be required bythe practice and kept in the employee’s personnelfolder or other secure location.

Employee handbooks should be written by a lawyerspecializing in employment law or by consultants whoprovide HR advice. A poorly written handbook maycontain legal pitfalls that can lead to litigation. Thefollowing suggestions may help avoid some commonerrors:

1. A statement that conforms to your state’s‘‘employment-at-will’’ doctrine, which specifiesthat employment can be terminated at any time,for any reason, or no reason at all, will generallyprovide some measure of protection against suc-cessful litigation. Good advice here is critical,because construction of the document, obtainingwritten acknowledgement by the employee, publicpolicy exceptions, situations where an expressedor implied employment contract exists, and‘‘situations where an implicit duty of good faithexists in the employment relationship’’ can lead toconfusion and ultimately to litigation.84

2. Announcing a ‘‘probationary period’’ of employ-ment may wrongly imply that employees areentitled to continuing employment after the pro-bation period is over.

3. Employee manuals should not include benefitplan documents, but simply point employeestoward other documentation.

4. Do not outline specific pre-firing procedures,because courts have held employers liable for‘‘wrongful termination when those steps were notfollowed.’’85

5. Generally, paychecks must be paid within a spe-cified time limit, so be sure to specify these guide-lines in accordance with local wage and hourlaws.

6. Ensure that employees sign an acknowledgementthat they have received, read, and agreed to theprovisions of the handbook. Otherwise, anemployee may claim that he or she never receivedthe manual.

7. Limitations on employee–employee communica-tions about wages or benefits are not allowed.

The employee handbook should be a positive toolfor promoting better communication and improvingmorale. Be sure to review the handbook at leastannually to be sure it is consistent with office policies.Also, annualizing employee performance reviews, raisesand updating state and federal withholding forms to

coincide with the date of hire for each employee, willhelp improve compliance by the practice.

EMPLOYEE SELECTION CRITERIAWhat are the predictors of the best job performance? Inan article reviewing 85 years of the practical and theo-retical implications of personnel psychology, research-ers Schmidt and Hunter86 have shown that, on average,intelligence or general mental ability (GMA) is themost useful primary personnel measure for hiring deci-sions when compared to all other attributes, includingconscientiousness. The positive economic effects ofassessing an applicant’s intelligence and hiring onlythe top performers cannot be overestimated. Further-more, this study states that performance in a skilled jobwill benefit more from a higher GMA than perfor-mance in a semi-skilled job. It turns out that peoplewith a high GMA scientifically correlate with conscien-tiousness, agreeableness, and emotional stability.87

Other studies have demonstrated that while intelligenceis the best single predictor of performance, screeningemployees for how well their values fit with theiremployer’s values (value fit) is also a predictor ofemployee satisfaction and retention. However, wheninterdependent tasks were measured against non-inter-dependent tasks, value fit predicted only better citizen-ship behaviors, not higher performance.88

Of course, the success of your practice will depend,in part, on the people you hire. Ritz-Carlton hotelsuse an elaborate system for assessing job candidates,and the qualities the company believes are crucial toits success. When Paul Hemp,89 a senior editor at theHarvard Business Review, spent a week at the hotel as aroom-service waiter, he went through the newemployee interview to see if he was the kind of candi-date the Ritz was looking for. He said that ‘‘even afterfudging my answers to a few questions, I got only tenpoints out of a possible fifteen in the composite hos-pitality assessment.’’ The interviewer told Hemp thata score of 10 was not bad, but they wanted someonewith a score of 12. He later found that just taking careof his sister in a time of need was not an extraordinaryexample of caring, but if he had given her his housefor a month, he would have earned a higher score.Using scientifically based criteria, the Ritz has mana-ged to reduce its annual employee turnover from theindustry average of 55 to 28%!

Surveys that rank the importance of pay is anotherarea of interest for the endodontic practice. Researchhas shown that self-reports of pay significance arelikely to ‘‘underestimate its importance due to norms

Chapter 41 / Operations Management in Endodontic Practice / 1501

that view money as a somewhat crass source of moti-vation.’’90 But money speaks, and getting the rightcombination of remuneration and benefits will posi-tively impact your practice.

However, be certain to have any pre-employmentexams or surveys thoroughly reviewed by an attorneyor HR consultancy in order to ensure that it does notunintentionally skew results that disfavor applicantsbased on their protected EEO classes.

HIRING THE BEST PERSON FOR THE JOBThe hiring process should begin only after creating aset of job descriptions and an employee handbook.Once these documents are created, the next step isplacing a job announcement in the print or onlinemedia or contracting with an employment agency.Typically, the Internet will produce same-day resultsand can be placed free of charge or on fee-based sites.An example of a job announcement for a PatientCoordinator written for Craig’s List, a popular onlinelisting service follows:

Dental specialty office has immediate opening for aPatient Coordinator with a friendly attitude. If youshare our vision of a customer-centered focus with ahigh-tech approach, this is the job for you! We arelooking for someone who is a team player and enthu-siastic (someone who likes to smile). You will needexcellent telephone and customer service skills. Profi-ciency with MS Word and Excel is required. Respon-sibilities include answering the phones, scheduling,and welcoming new patients, billing, and organizingpractice promotion activities.

This position requires some schedule flexibility aspatient appointments may occasionally extend theworkday. Our usual hours of operation are Mondayto Friday 8:15 am until 5:15 pm. Employee handbookand complete benefits package including medical andparking await the right candidate. Please email yourresume without attachments (cut and paste into bodyof email).

When candidates respond to the job announce-ment, a pre-interview screening of the applicationsby the person in charge of personnel can help inchoosing the best qualified candidates. Ideally, thescreener should review the applications for basicobjective criteria and reject those that do not possessthe minimum education, experience, or skills set.Having a formal intermediary step in the screeningprocess may help insulate against litigation because itwill interject an objectively neutral perspective intothe hiring process that can mitigate any claims of bias.

It may also be helpful for you to conduct brieftelephone interview with each of the remaining can-didates. Asking a few open-ended questions like ‘‘Tellme about your recent job experience’’ may help toidentify those applicants you deem worthy of furtherconsideration and will provide an opportunity for thecandidate to ask questions to determine whether theybelieve the job is right for them. After a positivephone conversation, invite the candidate for a face-to-face interview.

Have a job application form ready for the newcandidate and make sure it includes appropriate lan-guage authorizing reference checks. Notifying the can-didate of your intention to check references gives thecandidate time to alert contacts to expect yourinquiry. If you want to know what the prospectiveemployee is really like, contacting his or her formeremployers may be the best way to find out. Manycompanies check references as the final part of theirhiring process, and sometimes extend job offers withthe condition that references check out. Using a refer-ence request form with a waiver signed by the pro-spective hire is a good way to safely get the informa-tion. Try contacting former employers et al. at morethan one company, if possible, to get the broadestpicture of the candidate. It is best to restrict questionsto those that relate to education, training, experience,qualifications, job performance, professional conduct,and reason for termination.

Check with your attorney or HR consultancy tomake sure that you are in compliance with stateemployment laws. To ensure that the informationexchanged is from a legitimate former employer, tryusing fax or mail to verify the information. To helpmake the process a little less litigious, many stateshave enacted legislation providing some immunityfrom civil liability for providing information aboutthe employee. Also, many employers have their ownpolicies regarding reference checks on current andformer employees that restrict the information theydivulge to position title and dates of employment. Ifyou encounter such a response, do not automaticallyassume that the applicant had a negative employmentexperience with their previous employer.

The purpose of the initial interview is to form animpression of how the candidate will fit into thepractice culture, confirm his or her technical skills,and narrow down the field of applicants. Keep arecord of the conversation, with each question andanswer documented for future reference. Always meetcandidates at your office during regular businesshours with other staff on premises during the entiremeeting to preclude any chance of allegations of

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inappropriate behavior. Unfortunately, many inter-viewers are improperly trained or uninterested inmeeting with applicants. Nonetheless, endodonticpractices, like other small businesses, need to adhereto good hiring practices or hire employees throughemployment agencies. Because many questions canopen the door to non-job-related information thatmay be illegal, try to formulate behavioral questionsguided by the job description. Having this list ofquestions ready will ensure that you get the preciseinformation you need every time. Examples of goodquestions to ask are the following:

1. Tell me about a time when your teamwork with aco-worker helped you meet a patient’s needs.

2. Give me an example of a mistake you made whilecarrying out your job duties. What happened?How did you correct the mistake?

3. Tell me the procedures used for sterilizing a treat-ment setup.

4. What steps do you take to ensure patient andoperator safety when working with a patient?

Asking the right questions allows you to control theinterview and helps to make certain that the interviewis legally compliant.91 It is important that you ask thesame questions for each candidate during the hiringprocess to ensure that each applicant is treatedequally.

Remember that there are areas where cautionshould be used in making pre-employment inquiries.Whether asked on an application form or in an inter-view, the EEO Commission and state Departments ofLabor will consider some questions as evidence ofdiscrimination, unless the employer is able to showthat the inquiries are job-related or that there is adocumented business-related necessity for asking thequestion. Partial list of subject areas to avoid duringinterviews:92

1. Arrest records2. Garnishment records3. Marital status4. Child-care provisions5. Contraceptive practices6. Pregnancy and future childbearing plans7. Physical or mental disabilities8. Age, height, and weight9. Nationality, race, or ancestry

10. Other areas of potential discrimination includecertain limiting physical requirements, availabilityfor weekend work, appearance standards, andfluency of the English language

Always avoid asking about the applicant’s immigra-tion or citizenship status. Although it will be neces-sary for the applicant to establish that they are law-fully permitted work in the United States, questionsregarding the specific immigration status of the appli-cant can give rise to national origin discriminationclaims. It is permissible to ask the applicant the yes orno question ‘‘are you lawfully permitted to work inthe United States?’’

Interviewers should avoid any assurances related tojob security. Assuring the interviewee that they will‘‘have their job for as long as they do a good job’’ isfraught with risk. If the applicant accepts the job and6 months later is laid off, a breach of contract claimcould be filed, where the employee asserts that he orshe cannot be terminated unless they did not do agood job.

Once an offer of employment has been extendedand the candidate has accepted the offer, a welcomepacket of office information should be presented. Thispacket can include a welcome letter, employee hand-book, a listing of compensation and benefits,employee roster, hepatitis vaccination verification ordeclination form (if applicable), health insuranceapplication, payment options, retirement plans (ifapplicable), and any other information deemedimportant for the new employee. In addition, federaland state withholding forms, along with the Depart-ment of Homeland Security, U.S. Citizenship andImmigration Services’ Employment Eligibility Verifi-cation form must be completed within 3 business daysof the employment commencement date.93

POSTING OF EMPLOYEE NOTICESThe US DOL94 and all states including the District ofColumbia require that notices be provided toemployees and/or posted in the workplace whereemployees can readily observe them.95 Designatinga wall area in the employee locker room or breakroom will provide an ideal place for a bulletin boardto post periodic notices to staff and federal and stateposters. DOL provides free electronic and printedcopies of these required notices and posters at the‘‘elaws� Poster Advisor’’ on the DOL Web site.96

State posting requirements can be determined bycontacting your state DOL through the links pagelocated on the DOL Web site. In addition, somestates, like California, require distribution of pamph-lets, such as the State Disability Insurance and PaidFamily Leave pamphlets, to employees under certaincircumstances.97

Chapter 41 / Operations Management in Endodontic Practice / 1503

EMPLOYEE BENEFIT AND SALARYADMINISTRATIONCompliance with statutory wage and hour require-ments is one of the areas that endodontic practicesmay find confusing, that is, hourly versus salariedcompensation or complying with wage and hourrequirements for staff travel to and attendance atcontinuing education meetings. Be sure to check withyour HR advisors to determine the best policy.

Many practices use outside services for payroll pro-cessing and tax filing (i.e., W-2 and 1099 annualfiling), reducing the chance of errors and incorrectfiling of federal and state taxes. According to a recentstudy, the average small business that ‘‘ran payroll in-house and filed and paid quarterly taxes manuallyspent more than 250 hours away from customers . . .doing these tasks.’’98 Offering direct deposit of wagesto each employee’s own bank account is an additionalway to improve security and encourage staff membersto maintain individual privacy and avoid salary com-parisons. Direct deposit has the added advantage ofensuring that wages are available to employees asquickly as possible. No one benefits by stressed-outstaff members leaving the office during the businessday to deposit their payroll checks. Check your statewage and hour laws to determine if you can requiredirect deposit before mandating this service. Somenew endodontic practice management software evenincludes timesheets with biometric fingerprint identi-fication technology.

Additional information is available from the Amer-ican Dental Assistants Association, ADA, DentalAssisting National Board, Inc. and the DOL, Bureauof Labor Statistics, on the national estimates for den-tal assistant wages, including industry and metropoli-tan area profiles for this occupation (Table 5).

There are several important laws governing salaryand benefits compensation packages. The Fair LaborStandards Act (FLSA), the Employee RetirementIncome Security Act (ERISA), and the (HIPAA)impose a myriad of complicated rules and regulationsgoverning retirement plans, health insurance, cafeteriaplans, and other benefits of employment. It is impor-tant that you seek guidance from a plan benefits advi-sor and attorney or HR consultant in deciding how tostructure your employee salary and benefits packages.

TERMINATIONFew practice owners or managers want to face theemotionally charged process of firing people. Termi-nating employees in a way that preserves their dignitywhile preventing costly mistakes will benefit both theemployee and the practice. The actual terminationprocess will stay in everyone’s mind for a long timeand speak volumes about the practice. At best, asuccessful termination can make the employee afriend of the practice and in the worst scenario canresult in a costly legal process. A termination will alsoaffect co-workers if not handled properly, even if theemployee is not well liked. Remember that in mostjurisdictions, employees have the right to claimunemployment benefits which will often raise thepractice’s tax rate. The burden of proof is almostalways on the practice to prove the reason for theseparation in unemployment claims cases.

Even after carefully vetting new employees, he orshe may not meet your expectations or may even actillegally. As soon as performance or discipline pro-blems become apparent, start documenting yourcommunications with the employee in question.Before terminating an employee, review your

Table 5 Dental Assistant Wages

Employment Employment RSE Mean Hourly Wage Mean Annual Wage Wage RSE

270,720 1.3% $14.41 $29,970 0.6%

Percentile wage estimates for this occupation

Percentile 10% 25% 50% (Median) 75% 90%

Hourly Wage $9.46 $11.53 $14.19 $16.92 $20.21

Annual Wage $19,680 $23,980 $29,520 $35,190 $42,030

Employment estimate and mean wage estimates for all categories of dental assistants, (31-9091) for May 2005 (Adapted from http://www.bls.gov/oes/current/

oes319091.htm, accessed March 2, 2007). According to the Dental Assisting National Board, certified dental assistants earn higher wages than those who are not

certified (Adapted from http://www.dentalassisting.com, accessed March 2, 2007).

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employment offer letters, company policies, hand-books, and performance reviews to assure compliancewith the practice’s policies. If an employee performancereview was conducted, exercising special care will helpreduce the chances of litigation in the following situa-tions: (1) when firing someone who has filed priorcomplaints about harassment or Occupational Safetyand Health Act (OSHA) violations; (2) is older than 40and covered by the Age Discrimination in EmploymentAct (ADEA); (3) is a member of a minority groupbecause of race, color, gender, religion, or nationalorigin; (4) has an employment contract; (5) has beenpromised job security or long tenure; and (6) if you arelaying off more than one employee at once. In all cases,every employee must be treated even-handedly.

In determining whether to discipline or terminatean employee, it may be helpful to consider variousfactors to preserve objectivity. Consider the following:

1. The nature and seriousness of the offense and itsrelation to the employee’s duties, position, andresponsibilities, including whether the offense wasintentional, technical, inadvertent, malicious, forpersonal gain, or was frequently repeated.

2. The employee’s job level and type of employment,including supervisory or fiduciary role and con-tacts with customers.

3. The employee’s past disciplinary record.4. The employee’s past work record, including length

of service, performance on the job, ability to getalong with fellow workers, and dependability.

5. The effect of the offense upon the employee’sability to perform at a satisfactory level and itseffect upon supervisors’ confidence in the employ-ee’s work ability to perform assigned duties.

6. Consistency of the penalty with those imposedupon other employees for the same or similaroffenses.

7. The notoriety of the offense or its impact uponthe reputation of the practice.

8. The clarity with which the employee was onnotice of any rules that were violated in commit-ting the offense or had been warned about theconduct in question.

9. The potential for the employee’s rehabilitation.10. Mitigating circumstances surrounding the offense

such as unusual job tensions, personality pro-blems, mental impairment, harassment, or badfaith, malice or provocation on the part of othersinvolved in the matter.

11. The adequacy and effectiveness of alternativesanctions to deter such conduct in the future bythe employee or others.

Although this list is not complete, it is a good start-ing point to consider when dealing with employeemisconduct.

In sensitive firing situations or if terminating anemployee is new to you, consult with an experiencedemployment lawyer or labor advisor ahead of time toprepare what to say, understand state laws that governtermination, and have all paperwork, salary checks,and severance pay ready to give to the employee.Always keep all discussions confidential and documentthe termination to aid in future communications withany state or federal agencies. Be prepared to answer theemployee’s questions about their schedule, severancepay, references, what will co-workers be told, medicaland other insurance benefits, keys and security cards,profit sharing plan, if any, and eligibility for unem-ployment insurance.

Conducting an exit interview is another way toimprove the work environment for the practice. Exitinterviews should be conducted separately from thetermination meeting and in small practices can be asimple survey to be mailed back or a phone conversa-tion. Explain that the purpose of the interview is togather information about the employee’s experienceat the practice and how it treats employees. Be sure toset the right tone, stay objective, and listen withoutproviding opinions or becoming defensive.

EMPLOYMENT LAWMany dentists assume that as they are practicing in an‘‘at-will’’ state, they can discharge employees at any-time without problems. In certain circumstances,other issues can supersede the ‘‘at-will’’ prerogative,like violating an employee’s civil rights. For example,the practice cannot discriminate against an employeewho belongs to a protected class, where issues regard-ing age, sex, race, color, religion, disability, or nationalorigin may play a role. Get the advice of legal councilor your HR advisory firm if you plan to discharge anemployee whose dismissal may trigger other issues.

It is best to administer your employment practicesin a fair, equal, and consistent manner by counselingand documenting disciplinary and performance pro-blems in written form. Include specific comments(i.e., reason for counseling, nature of disciplinaryaction, corrective action expected, consequences ofnon-compliance, and employee and employer com-ments) that are dated and signed by the administra-tor, employee, and a neutral witness, if possible. Neverinclude an employee’s co-workers or peers in thetermination process.99

Chapter 41 / Operations Management in Endodontic Practice / 1505

The following suggestions may help avoid commonlegal pitfalls

1. Maintain two types of personnel files for eachemployee, regular and confidential. The I-9 formshould be kept in the confidential file and shouldnot be given to anyone for inspection withoutlegal advice. The I-9 form should be kept for 3years from date of hire or 1 year from termina-tion, which ever is longer.

2. Have an established protocol to follow when anemployee or former employee or their attorneyasks to review his or her personnel file.

3. Have a signed employment handbook with eachemployee.

4. Prohibiting employees from talking about theirwages or benefits is not allowed under theNational Labor Relations Act which specifies theright of employees at all workplaces, unionized ornot, to engage in collective bargaining.

5. To protect the privacy of employees, keep allemployee files locked or off-site. Records in manystates can only be disposed of by destruction,modification, or other reasonable action to pro-tect personal information.99

6. Employee records must be maintained on the fol-lowing schedule.100 OSHA: OSHA requires thatrecords of job-related injuries and illnesses be keptfor 5 years. Employers are also required to fill outand post an annual summary. Any exposure totoxic substances and blood-borne pathogens alongwith any records related to medical exams must beretained for 30 years after termination of employ-ment. FLSA: Under the FLSA, the record-keepingrequirements are 3 years to cover both supplemen-tary basic records and payroll records. Civil RightsAct of 1964, Title VII, ADEA and the Americanswith Disabilities Act (AwDA): Under the CivilRights Act of 1964, Title VII, and the AwDA,employers with at least 15 employees must retainapplications and other personnel records relatingto hires, rehires, tests used in employment, promo-tion, transfers, demotions, selection for training,layoff, recall, terminations of discharge, for 1 yearfrom making the record or taking the personnelaction. The ADEA requires the retention of thesame records for 1 year for employers with 20 ormore employees. Title VII and the AwDA requirethat basic employee demographic data, pay rates,and weekly compensation records be retained forat least 1 year.

7. Family and Medical Leave Act (FMLA): TheFMLA requires the retention of certain records

for 3 years with respect to payroll and demo-graphic information as well as informationrelated to the individual employee’s leave ofabsence.

8. IRS: IRS rules require keeping copies of employ-ment tax records (Social Security documents) for4 years after the due date of the tax. If a claimantfiles a claim, the retention period should extendfor 4 years after the date of the filing. (26 CFR31.6001).

Other employment law issues to be aware ofinclude the following:

1. The Uniformed Services Employment and Reem-ployment Rights Act (USERRA): USERRArequires employers to hold available the positionof employees who are active reservists called forduty. This includes short-term assignments fortraining which may only require a few days ofleave, or long-term active duty in times of con-flict. Additional guidance may be found at theDOL Web site at http://www.dol.gov/elaws/userra.htm.

2. The Pregnancy Discrimination Act: An amendmentto Title VII of the Civil Rights Act of 1964, thePregnancy Discrimination Act prohibits anemployer from treating an employee who becomespregnant differently than any other employee witha serious medical condition. For example, if yourpractice grants extended leave (either paid orunpaid) to an employee recovering from a heartattack, you must grant the same consideration to apregnant employee. Keep in mind, that pregnantemployees may also have additional rights underthe Family Medical Leave Act.

3. Sexual Harassment: It is imperative that yourpractice have a strongly worded written policystating that sexual harassment will not be toler-ated. It should include a provision that employeeswho report sexual harassment will not be reta-liated against and notify them of a confidentialprocess for reporting any instances of harassment.You should take prompt and remedial action inaddressing any allegations of harassment includ-ing investigating the claims, separating the personwho reported the harassment from the allegedharasser, and taking any necessary disciplinaryactions. For more information, please refer tothe U.S. Equal Employment Opportunities Com-mission (EEOC) guidance at http://www.eeoc.gov/policy/docs/harassment.html.

4. Local Laws: Local laws may expand or modifyFederal employment statues, so it is necessary that

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you consult with an attorney or HR consultancyto become aware of any additional requirements.For example, some jurisdictions also prohibit dis-crimination on the bases of sexual orientationand/or political affiliation.

CONFIDENTIALITY ANDNON-COMPETITION COVENANTSSome employers require employees to sign non-com-pete covenants and confidentiality clauses. Generally,non-competition covenants with administrative orclerical staff will be held invalid. Some firms maylegitimately enter into non-competition clauses withassociates or other professional staff within their prac-tice so long as they are for a limited duration (1 or 2years); not overly restrictive (limited to a specialtypractice and not the entire medical or dental profes-sion); and of a limited geographic scope (a few mileradius of the current practice location). Keep in mindstate laws and professional ethics rules may bar anynon-compete covenants.

Contrary to covenants not to compete, confidenti-ality clauses can be enforced so long as they pertain toproprietary procedures or information and patientmedical information. Consult with an attorney ifyou are considering either covenant.

EMPLOYMENT LIABILITY PRACTICESINSURANCELiability arising from employment practices continuesan upward trend that shows no signs of abating.Unlike comprehensive general liability (CGL) policies,which insure against claims for tangible damages, forexample, property damage, employment practices lia-bility insurance (EPLI) insures against claims arisingfrom employment practices. CGL policies differ fromEPLI policies by excluding intentional acts and bodilyinjury that might occur while working. Also, CGLpolicies cover claims made while the policy is in effect,even if the claim is brought years later, whereas EPLIwill cover only claims made during the coverage per-iod or claims that the employer knew about or shouldhave known about during the coverage period.

Many EPLI policies include wording that requiresthe insurance carrier to defend the employer againstclaims, even if the deductible has not been met. How-ever, these clauses allow the carrier to choose theattorney who will defend the employer against theclaim. Some policies also contain a provision thatallows the carrier to settle the case, and if theemployer rejects the settlement offer, the carrier canlimit its liability to the amount offered in settlement

or require arbitration. Before purchasing coverage,carefully review limitations and exclusions to makesure the policy fits your needs, as follows: (1) find outwhat is covered in addition to wrongful termination,harassment, and discrimination, such as invasion ofprivacy, negligent supervision, and hiring issues; (2)check to see if the policy will cover claims made bycurrent part-time or temporary employees, indepen-dent contractors, and the EEOC; (3) confirm that youcan choose your legal defense team; and (4) choose acarrier that has a solid track record in the field.

WORKERS’ COMPENSATIONWorkers’ compensation provides wage replacementbenefits, medical treatment, vocational rehabilitation,and other benefits to certain workers or their depen-dents that experience work-related injury or an occu-pationally related disease. Workers’ compensationclaims can be minimized by ensuring a safe workplaceand making sure employees are capable of performingtheir jobs before they are hired. Employers cannot askabout a prospective employee’s Workers’ compensa-tion history before a job offer is made.

Whenever a work-related injury occurs, make surethat an accident report is completed and a notifica-tion is provided to your Workers’ compensationinsurance provider. Any work-related injury thatoccurs over a period of time, like carpal tunnel syn-drome or hearing loss, must be reported by theemployee as soon as he or she learns that it is work-related.

STAFF MEETINGS AND PEAKPERFORMANCEAs the U.S. demographic picture continues to change,and the population/dentist ratio exacerbates health-care manpower shortages, especially in rural andunderserved areas, there has never been a greater needfor the dental team to work more efficiently. Dentalpractices must not only ‘‘provide optimum patientcare, but also must operate as a profit-making busi-ness’’101 to ensure the ability to upgrade facilities andacquire new technologies and training

Along with hiring the right people, using meetingsto enhance peak performance and improve servicequality are the hallmarks of a well run office. The‘‘morning huddle,’’ a 10- to 15-minute briefing, facili-tated by the patient coordinator, is a valuable way tokeep up-to-date on patients, procedures, scheduling,upcoming events, and miscellaneous matters. As agroup, determining the best place to schedule emer-gency patients and share suggestions about how to fill

Chapter 41 / Operations Management in Endodontic Practice / 1507

appointment openings will improve efficiency andreduce stress. The agenda should include a briefreview of production and collections from the pre-vious day, expected for the current day, and themonth, along with some time to discuss operationalissues that need attention. Try to end on a positivenote, adding a birthday or anniversary acknowledge-ment, a joke or a complement.102

Regular staff meetings are another way that prac-tices stay ahead. Start by creating a file for staff toplace suggestions and complaints between meetings (aword processing file accessible to all computers on thenetwork will be helpful). Make the meetings a safeenvironment for all to be heard, take minutes, andcreate a written action plan that gets reviewed in 48hours to measure progress.103 Hotel chains like theRitz-Carlton, home of legendary customer serviceexcellence and two-time winner of the Malcolm Bal-dridge Award, have pioneered many innovations incustomer service. Believing that employees are one ofthe keys to success, the Ritz-Carlton hotels ‘‘win thehearts and minds of its employees by making themfeel part of a proud heritage.’’104 Success in dentalpractice, and any profession for that matter, involvesthe construction of organizational processes and cap-abilities necessary to achieve performance throughpeople delivering results and process quality.

Lastly, and all too often, organizations reach theirgoals and start planning new initiatives while forget-ting to celebrate their accomplishments. Take time toacknowledge practice accomplishments by schedulingevents, sending letters of praise, and giving outbonuses that say ‘‘Thank You!’’

Acknowledgements

Thank you to the following experts who reviewedsections of the manuscript for this project: GregoryL. Morgan, Managing Director, Sperry Van Ness—Morgan Realty Advisors, Inc.; Robert S. Rubin,Ph.D., Assistant Professor of Management, DePaulUniversity; Frank Hotchkiss, Operations Manager,Bent Ericksen & Associates; Janet L. Cornfeld, Ph.D.,Clinical Psychologist; Charles J. Levin, Esq., LandlordAttorney; Kevin L. Owen, Esq., Labor and Employ-ment Attorney; and Susan D. Levin, my wife andCFO.

Disclaimer: The information in this chapter shouldnot be construed as legal advice or a standard ofcare. Readers should not act upon any informationunless they consult with an attorney as management

advice must be tailored to the specific circum-stances of each case. Nothing provided hereinshould be used as a substitute for individual endo-dontic or dental management advice. Laws varyconsiderably from jurisdiction to jurisdiction, andeven within jurisdictions. Therefore, some informa-tion may not be correct for a jurisdiction or locale.

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Chapter 41 / Operations Management in Endodontic Practice / 1511

INDEX

Page numbers followed by ‘‘f’’ indicate figures; page numbers followed by ‘‘t’’ indicate tables.

A

AAE. See Association ofEndodontists (AAE)

Abscess theory, 313, 506Abutment tooth selection

technique, 1461Access cavity, 894, 1127

magnified view, 1098fpreparation, 877

effect on structural integrity,1033

finding pulp chamber, 895increased susceptibility to

fracture, 918fobtaining SLA, 894obtain uniform contact of file,

861penetration through occlusal

surface, 896sequence of steps, 927funroofing dentin, 886

types of designs, 943varying according to degree of

curvature, 887Actinomyces, 258Actinomyces israelii, 500Activated pathways during

inflammatory response,353f

Acute inflammation, 345, 473–474histologic evidence,

inflammation inunderlying pulp, 473f

polymorphonuclear leukocytes,early inflammation, 474f

Acute inflammatory process, 381Acute rhinosinusitis, 628. See also

Chronic rhinosinusitis;Subacute rhinosinusitis

ADA. See American DentalAssociation (ADA)

Adaptive immunity, cells ofregulatory T lymphocytes, 351fsubpopulations of T cells, 349tT cells and Naıve CD4 T cells,

349–350T cytotoxic and B cells,

348–357Th3 cells, 349Treg and Tr1 cells, 350

A-� fibers, 664Adjunctive procedures, root canal

treatment, 113Adjunctive therapy, 1350Adrenal suppression and long-term

steroid use, 770Adverse effects, drugs combination

coumadin with quinolone, 784digoxin–tetracycline, 784macrolide–quinolone

combination, 784methotrexate with penicillin, 780

AEL. See Electronic apex locator(AEL)

AH 26 (thermaseal), 1071–1072fluid conductance model, 1071f

ALARA, 574, 584Allergy to materials used in

endodontic therapy, 770,771f

Alveolar bone, 13Amalgam

perforation repair, 1156Ameloblastoma, 616f

desmoplastic type, 617fgrowth/removal, 101f

American Association ofEndodontists (AAE), 86,93, 103, 266, 660

American Dental Association(ADA), 4, 87, 88, 113,709, 748, 814, 1476

American Endodontic Society, 1066American National Standards

Institute (ANSI), 814, 1036American Society of

Anesthesiologists (ASA),749

categories and classifications,755–758

Anaerobic bacteriologictechniques, 24

Anatomic apex, 25Anesthetics and drugs, 786tANSI. See American National

Standards Institute(ANSI)

Anterior cingulated cortex (ACC),398

Antibacterial/microbial activity,992

CHX, 1005–1010EDTA, citric acid and other

acids, 990–1015hydrogen peroxide, 1002NaOCl, 994–997

Antibiotic prophylaxis regimens forpatients with total jointreplacement, 768f

Antibiotics, 775and analgesics, 772–776and effects on oral

contraceptives, 751Anticoagulant therapy and

bleeding disordersdiscontinuing aspirin prior to

proposed surgery, 760modification of anticoagulant

therapy, 760

1513

Antigen-presenting cells (APCs), 497Antimicrobial peptides,

�-defensins, 360Anxiety/fear problem, endodonticsmanagement, 741recognition, 748–749

APCs. See Antigen-presenting cells(APCs)

APEXIT, 1070Apical cholesteatoma, 325Apical constriction, 25, 930lost, 930

Apical dental cyst, 584fApical diagnosisacute apical abscess, 529acute/chronic apical abscess, 529apical scar, 529asymptomatic apical

periodontitis, 529cellulitis, 529condensing osteitis, 529normal periapical tissues, 529prognosis and informed consent,

530–531symptomatic apical

periodontitis, 529Apical foramen, 25, 640Apical lamina duraresorption/remodeling of, 602,

602fsurgical endodontic, 602

Apical leakage, 1068delayed filling and, 1098, 1079fand lasers, 1073mean leakage values of sealers,

1071fmicroleakage and its evaluation,

1068–1069smear layer and, 1073

Apical neurovascular damage,consequences

prevention of pulp spaceinfection, treatment,1343–1344

pulp canal obliteration, 1343multinucleated osteoclasts,

appearance of, 1343,1343f

pulp necrosis, 1348root canal disappearance,

placement of thickcalcium hydroxide, 1345,1345f

Apical patency/preparation, 28–29Apical perforation management,

1133Apical periodontitis, 2, 311, 603,

604, 887, 1092causage, 936cholesterol and, 324

crystals and cystic conditionof, 325f

clinical relevance of cysts,322–324

condensing at distal root, 603fcone beam CT, 606fcriteria for assessing healing of,

919cystic, 311fdiagnoses, 597

echographic examinations, 598endodontic orthograde

treatment, 597etiology of refractory, after

treatment, 1901–1903giant cell granuloma mimicking,

614fhealing of, 607, 607flesions, 318f, 321f

prevalence of cysts in posttreatment, 324t

microbial etiology of refractory,1192

molar with canal in mesiobuccalroot unfilled and with,605f

more frequent, 930origin of cyst epithelium, 344persistence or recurrence of, 1193per-treatment variables

apical enlargement, 1201bacterial culture before root

filling, 1197complications, 1209flare-up during treatment,

1198length of canal preparation

and filling, 1195–1199materials and techniques, 1207number of treatment sessions,

1198post-treatment variables

restoration, 1209–1211prevalence of

radicular cysts, 312tin 35–45 year-olds, 622f

radiographicaspects of, 605and histological appearance

of, 534freversal/regression in healing of,

1189fsuccess and failure of endodontic

treatment, 617–618teeth treated with associated, 1198

dynamics of healing, 1191functional teeth, 1191healed teeth, 1198–1199healing in progress, 1191

teeth treated without associateddynamics of developing

disease, 1184–1187functional teeth, 1184healed teeth, 1191

Apical scar, progressivedevelopment of, 1164

Apical sizes and preparationdiameter of, 886larger sizes, 944measured diameters and

suggested size for, 932tpre- and postoperative canal

diameters, 933fApical surgery, 324, 337follow-up studies reporting on

outcome, 1212tlaser in endodontics, 868outcome assessment of multi-

rooted tooth after, 1173fpotential for healing and retained

function after, 1201dynamics of healing, 1191functional teeth, 1191healed teeth, 1199–1192healing in progress, 1191

recurrence of disease, 1211fApical surgery, factors influencing

healing after, 1210post-treatment variable

dynamics of resorption, 1211endodontic treatment,

outcome, 1222–1224potential for healing and

function afterreplantation, 1119–1121

results of biopsy, 1209pretreatment variables

age, gender, and systemichealth of patient, 1212

1514 / Index

apparent quality of previousroot filling, 1195

clinical signs and symptoms,1202

restoration, 1213size of radiolucency, 1202supporting bone loss, 1202tooth location, 1201–1204

second-time surgery,pretreatment variables,1202–1207

antibiotics, 1214barriers and bone grafting

substances, 1209complications, 1209hemostasis, 1214laser irradiation, 1209level of apical resection and

degree of beveling, 1204magnification and

illumination, 1208operator’s skill, 1209presence or absence of

root-end filling, 1214quality and depth of root-end

filling, 1205retrograde root canal

re-treatment, 1208root-end cavity design, 1205root-end filling material,

1214–1215surgical and orthograde

treatment, 1208Apical surgery, persistent infection

after, 1203–1204healing after

endodontic treatment, 1201nonsurgical treatment, 1201

pretreatment variablesage and gender of patient,

1201–1204apparent quality of previous

root filling (in re-treatment), 1202

clinical signs and symptoms,1202

elapsed time after previoustreatment (in re-treatment), 1195

periodontal support,1194–1195

presence/absence,radiolucency, 1205

previous perforation (inre-treatment), 1195

pulp vitality or necrosis (ininitial treatment), 1194

size of radiolucency, 1202systemic health, 1201–1205tooth location, 1201

Apicalterminus/cleaning, apicalpatency, 25–28

Apical transportation, managingType I transportation, 1124Type II transportation,

1124–1125clinical steps for, 1126fMTA as barrier for choice of,

1133–1135Type III transportation, 1125

Apical true cysts, 313Apicoectomy. See Root-end

resectionsApplications of LDF, dentistry

clinical dentistry, 551dental trauma, 551

Appropriateness, Care and QualityAssurance Guidelines

AAE, 88Arachidonic acid, prostaglandins/

leukotrienes, 395Armamentarium, clinical, 885

accessory instruments, 895–896Stropko Irrigator, 885–896

burs, 888examples, 890frotary instruments, 885

Arrhythmias and cardiacpacemakers, 761

Arteriovenous anastomosis (AVA),131

and ‘‘U’’-turn loops blood flow,regulation of, 132, 133f

Association of Endodontists(AAE), 809

guidelines of, 56Assorted gutta-percha points,

1022fAsthma, 763Atherosclerosis, 324

high level of cholesterol, 324Automatic Exposure

Compensation (AEC),573, 586

Autotransplantation of humanteeth, 31

Avulsed toothopen/closed apex, 1339–1152

dry time, 1356replant, 1357

B

Bacteriacoccal forms of, 225fcultured/identified from root

canals of teeth with apicalradiolucencies, 227t

in dentin repair, 224finfluencing the outcome,

242–243persistence after intracanal

disinfection procedures,242t

intracanal disinfectionprocedures, 241

invasion of pulp cavity, 225one visit versus two visits, 240–241

post-instrumentation/post-medication/post-obturation samples,240–241

Bacterial biofilms, 268–273characteristics, 270communication/exchange genetic

materials/acquiring newtraits, 271, 271f

criteria, 268dentistry, 277–278development, 271

co-aggregation/co-adhesion,273f

factors influencing initialbacteria–substrateinteraction, 272f

stages, 273fnutrient trapping/establishment

of metaboliccooperativity, 270

organized internalcompartmentalization,270–271

protection from environmentalthreats, 270

resistance of microbes,antimicrobials, 281–3,273–274

ultrastructure, 277–278, 269f

Index / 1515

Bacterial elimination in periapicallesions

apical periodontitis, pain,501–502

SRIF, 501–502athymic animals, studies in,

503–504bacteria in periapical lesions, 499

extraradicular infection, 499B cells/plasma cells/

immunoglobulinproduction

antigen-presenting cells(APCs), 497

bone-resorbing cytokines,cellular sources, 503–510

bone resorption in periapicallesions, 502–503

NSAIDs, 502cells/immunoglobulins/

cytokines, periapicallesions, 495

complement activation (chainreaction), 494

diapedesis, 494equilibrium, bacteria and host,

500–501‘‘phoenix abscess,’’ 500

flare-ups in periapical lesions,immunobiological view,500–501

immunobiological concept ofperiapical lesions,evolution, 495–496

local activation, nociceptors inapical granuloma, 501f

macrophage presence, kineticsof, 499

macrophages in periapicalgranuloma, 511–512, 505f

osteoclast activationosteoprotegerin ligand,

functions, 504PMNs, 494protective function of T

lymphocytes in periapicalgranuloma

T lymphocytes, role of,508–509, 505f

T lymphocytes, periapicalgranuloma, 497–498

Bacterial factors, flare-ups,707–708

Bacterial plaque, 318fBacteriostatic, 995Bacteroides melaninogenicus, 237BBHI-2. See Brief Battery for

Health Improvement(BBHI)

B-cell antigen receptor (BCRs), 348Behavioral factors, pain behaviors,

403Benzodiazepineand all drugs, 783t

Biofilm, 999Biomaterial-centered infection

(BCI), 285–286BioPure. See MTADBisphosphonate-associated

osteonecrosis of jaws, 766Bisphosponates, 967Bleaching of discolored dentin/

enamel, causes, 70Bleedingincreased risk of, 755

Blood flow rate, 133f‘‘Blunderbuss’’ canal, 27BMS. See Burning mouth

syndrome (BMS)Bone loss, fenestration type of, 679,

679fBone marrow and solid organ

transplantationhematopoietic stem cell

transplantation, 766–767Bone resorption, mechanisms ofmediators promote or inhibit, 364tregulations of osteoclast

differentiation and keycytokines, 365f

Brief Battery for HealthImprovement (BBHI), 406

Brynolf’s interpretation, 26fBuccal cusp, occlusal view, 1433fBull-like teeth. See TaurodontismBurning mouth syndrome (BMS),

453, 454–455

C

Calciobiotic root canal sealer, 1035Calcitonin gene-related peptide

(CGRP), 395, 461and substance P (SP receptors),

120, 120f

Calcitonin gene-related peptide-immunoreactive(CGRP-IR), 138f

immunohistochemical staining ofnerve fibers in rat dentalpulp, 138f

nerve fibers, 138f, 139fCalcium hydroxide, 992–912,

1067–1069for perforation repair, 1129periapical repair following

application of, 1968fCalcium hydroxide disinfection, 24Calcium phosphate cement (CPC),

1066–1067Calcium sulfateas perforation barrier material,

1142Campylobacter gracilis, 237Campylobacter rectus, 237Canal(s)accessory, 154curvature, observing

radiographically, 886managing blocked, lubrication,

1133shaping procedures, 907

effect of, anatomy, 961surface modification, 970–971

appearance after shaping, 933firrigation dynamics, 967photodynamic therapy, 970smear layer removal, 966t

surfaces, 969systems to prepare canal, 966tin tooth, identification of, 581transportation, 961types

Sert and Bayirli’s, 154fVertucci classification, 154f, 155f

variationsfactors contributing to,

151–152tin number of, 153

Canal, preparationanticurvature filing, 939balanced force, 940–946

description, 943principles of the, 965f

cross sections before and afterpreparation, 958f

crown-down pressureless, 942–943sequence of instruments in, 960f

1516 / Index

devices for powered, 951motors for rotary

instrumentation, 951–953sonic canal instrumentation,

954ultrasonic canal

instrumentation, 953–954double flare, 943handpieces with continuous

rotation, 961instruments

cutting blade design, 961instrument shaft design, 961k-files, 963

prevalence of instrumentsfracture, studies on, 983

relationship of torque during andfracture load, 953f

root canalaseptic techniques and

disinfectant, 1057, 1058ffilling/vertical root fracture,

959fpreparation, 959f

sequential mechanicalenlargement, 960f

standardized, 936–937step-back (telescopic technique),

937sequence of instruments, 938f

step-down, 945–946procedure itself, 938fpurpose, 945shaping coronal aspect, 938f,

945ultrasonic inserts fracturing, 955f

Canal Finder system, 951Cancer chemotherapy and

radiation therapy,765–767

Ca(OH)2. See Calcium hydroxideCapillary loops, 132fCapset. See Calcium sulfateCarbon fiber-reinforced (CFR)

epoxy resin post,1453–1454, 1453f

Caries removal, vital pulp therapycaries affected dentin, 1318rubber dam isolation, 1391

Catonella morbi, 237Causalgic pains

sympathetically maintainedpains (SMPs), 443–444

Cavit, 1042endodontic perforation repair,

1128Cavity

cleansing, 481crown preparation, 480

Cavity preparationaccess, 886–889

improper angulations and, 882fstandard hand instruments, 884

coronal access, 877CBVCT. See Cone-Beam

Computed Tomography(CBCT)

Cellulose granuloma, 334paper-point granuloma affecting

root-canal-treated humantooth, 335f

Cemental apposition, healing, 62fCementodentinal junction, 26Cemento-enamel junction (CEJ),

638, 883–884centered pulp chamber, 891f

Cements and pastes (fillingmaterials)

calcium hydroxide, 1067–1068calcium phosphate cement,

1066–1067dentin chip apical obturation,

1067–1068N2/Sargenti paste, 1066resin cements, 1067

Central incisors fluorosis, treated byexternal bleaching, 1385

Central mechanisms, 384alternative hypotheses, 385fsensitization, 384

Central nervous system (CNS), 393definition, 764depressants, 743t

Central trigeminal pain system,organization and functionof, 379

Cervical root resorption, 602f, 603fprogress, apical, 603f

CGRP. See Calcitonin gene-relatedpeptide (CGRP)

Charge-Coupled Device (CCD),573, 577, 581

Chemokinesadhesion molecules, tissue

distribution and ligands,353t

CC chemokines, 352common chemokines, receptors

and cells, 352tCXC chemokines, 352

Children, treatment foreducational curricula and

attitudes of pediatricdentists, 1423–1425

nonvital pulp therapy, 1417–1418pulpal pathosis in children,

diagnosis of, 1403Chlorhexidine digluconate (CHX),

1002–1006, 1010–1011Choice of practice, operations

management, 1474associate-employee/independent

contractor, 1478Internal Revenue Service

(IRS) guidelines, 1478part-time schemes,

combination, 1478hybrid, 1478new practice, 1477–1478practice models, 1476–1477

ADA, 1476–1477DTA, proposed model, 1477service factory model, 1477service theaters, 1477super-norm model/

Armstrong’s servicetheater approach, 1477

setting goals, 1476practice goals, 1476–1477

strategic planning, 1475–1476vision and mission statements,

1475‘‘22 Keys to Creating a

Meaningful Workplace,’’1475

mission, definitions, 1475PEST analysis, 1476SWOT analysis, 1476t

Cholesterol, 324apical periodontitis, 324–325crystals, accumulation of, 325cyclopentanoperhydrophe-

nanthrine, 324fin disease, 324Teflon cage model, 325tissue reaction to, 325, 326f, 327f

Chronic apical periodontitis, 1099Chronic inflammation, 345, 474–475

granuloma, 475

Index / 1517

pulpal abscess, 475beneath deep cavity

preparation, 486fChronic obstructive pulmonary

disease (COPD), 752Chronic rhinosinusitis, 628, 634Claims against, endodontists, 87tClark’s rule of horizontal

angulation, 560, 561f, 929.See also Ingle’s MBD rule

Cleaning/disinfecting, root canalsystem (laser), 860–861

Cleaning/shaping, instruments,813–838

basics. See Endodonticinstruments

Nickel-Titanium. See Ni-Tiendodontic instruments

rotary. See Rotary instrumentsClinical examination, endodontics,

524vital signs, 524

blood pressure/temperature/cancer screen, 524–525

coronal evaluation, 525extra/intra oral examination,

525Clinical guidelines, preoperative, 886assessing complicating factors, 886assessing occlusal/external root

form, 886determining point of penetration,

886radiographic assessment and

measurement, 886CMOS-APS, 573, 577–578CNS. See Central nervous system

(CNS)Codes of Ethics, ADA, 88, 102Collagen, 129–130as perforation barrier material,

1130Color power Doppler (CPD), 592application to echography, 593

confirming information, 593picture representing the echo, 608f

Complementary Metal OxideSemiconductor (CMOS),573, 577, 580f

Complement cascade, 354fComposite resins, 1042Computed Dental Radiography

(CDR), 573, 586

Cone-Beam Computed Tomography(CBCT), 573

demonstrating apical dental cyst,600f

Cone positioning, endodonticradiography, 559

horizontal cone angulations. SeeHorizontal coneangulations

long cone, 557short cone, 557teeth, 559f

Congestive heart failure, 761–762New York Heart Association’s

classification system, 762fCoronal access cavity preparation,

877Coronal disassembly devicesactive instruments, 1096–1097,

1097fgrasping instruments, 1096percussive instruments, 1096

Coronal evaluationintraorifice barrier, 1042

Coronal leakage, 645, 1091barrier, 645closure materials and variations

in, 1076, 1077fevaluation methods, 1056leak proof amalgam, 1078f

Coronal leakage and prognosis forhealing, 1091–1093

armamentaria and missed canals,1097–1100

coronal disassembly, 1095coronal disassembly devices. See

Coronal disassemblydevices

factors influencing restorativeremoval, 1095–1096

non-surgical versus surgicalretreatment, 1095

technology of retreatment,1094–1095

temporary coronal restorations,1093–1094

Coronal pulp, 131fCoronal restorations, temporary,

1093–1094Coronal restorative

procedures, 71root canal space/coronal access

openings, involvement, 71

Coronal tooth preparation, 1458,1458f

Corrective surgerybicuspidization, definition, 1281curved periodontal probe, 1279fdefinition, 1274hemisection, 1279–1281

completed on mandibularsecond molar withfracture, 1299f

periodontal regenerativeprocedures/contraindications, 1281

periradicular repair, 1295–1296replantation, intentional,

1281–1284root amputation, 1277–1279

nonsurgical root canaltherapy, 1277

root canal therapy, completed,1298f

traumatic root fracture repair,1277

Cracked tooth, 660Crown fracturescomplicated, 1330–1331

histologic appearance, pulpwithin 24 hours oftraumatic exposure, 1353f

concomitant attachmentdamage, 1331

restorative treatment plan,1331–1332

roothorizontal, 1304f, 1339treatment, 1341

time between accident/treatment,1331

tooth development, stage of‘‘blunderbuss,’’ 1331

treatment, 1331vital pulp therapy, 1313

C-shaped canals, 915Cuspal fracture odontalgiaidentification problem, 663

Cyclopentanoperhydrophenanthr-ine, 324f

Cyst, 311, 321bay cyst, 313nonsurgical root canal therapy, 322radicular cyst, 323f

apical pocket cysts, 315f, 316apical true cysts, 313

1518 / Index

Cystic apical periodontitis, 311fcysts and periapical healing,

321–322diagnosis of periapical cysts,

309–310foreign bodies, 328–332genesis of pocket cysts, 316–321genesis of true cysts, 313–316oral pulse granuloma, 332–334periapical cysts

histopathology of, 312–313incidence of, 309

Cystic lesions, 320–321ciliated columnar epithelial cells

(CEP) lining of, 312fCyst luminal wall, 317fCyst management, 60fCyst versus granulomas, 597

differential diagnosis, 595Cytokines

origin and actions of, 356–357troles of cytokines in

periradicular boneresorption, 366

systemic effects of, 358

D

Decayed-missing-filled (DMF), 10Decimated dentition, 15fDeep caries, treatment of,

1403–1405pulpotomy treatment and

indirect pulp therapy,1403–1405

success rate of, studies,1404–1405

Definitive restoration, type ofcoronal tooth preparation, 1458

DEJ. See Dentin-enamel junction(DEJ)

Dens evaginatus, 165, 201Dens invaginatus, 165

type 1, 162type 2, 162type 3, 160f, 161f, 158–165

radicular-form of, 165fDental claims, frequency, 87tDental implants

on endodontics, effects of, 108provisional restorations,

1296–1306

Dental materials, 482Dental pulp, 37, 119, 119f, 126. See

also Vital dental pulpchronology of discoveries

histology, 37t–38tpulpodentinal histology, 37

layers in, 126fphotos, 39fsensory and sympathetic nerves

to, 137fDental Trade Alliance (DTA), 1477Dental trauma, treatment methods

Cvek partial pulpotomy, 1335ffull pulpotomy, 1336partial pulpotomy, 1333

‘‘Cvek pulpotomy,’’ 1333pulp capping, 1333pulpectomy, 1336technique, 1333–1337

Dental treatmentlevel of compliance, 750modification of, 749need for modification

MD-RAM, 752, 753fphysical examination prior to, 751previous dental, 751recommendations for

modification of, 752stress of, 751

Dentin, 121permeability, 121fand pulp, balance between, 123fand pulp complex, structure of,

118sensitivity, theories of, 124tubules, 121

Dentinal hypersensitivity, 386Dentinal tubules

exposed, as communicationpathways between pulpand periodontal ligament,638, 608f

scanning electron micrograph ofopen, 639

Dentin chip apical obturation, 1067root canal plug after 3 months,

1068fDentin-enamel junction (DEJ), 481Dentin–pulp complex, 118

embryology, 118–121nerves in pulp

classification of nerves,136–137, 137t

distribution, 137–139function, 139–141neuropeptides, 137neurophysiology, 142–143receptors, 141–142

structures and functionsarteriovenous anastomosis and

‘‘U’’-turn loops, 131–132,132f

cellular structures, 127dental pulp, 125–126dental–pulp complex, 121dentin permeability, 121–123dentin sensitivity, 124–125dentin structure, 121extracellular matrix, 129fibers, 129–130fibroblast, 127ground substance, 130immunocompetent cells, 129interstitial fluid, 125–127low-compliance system theory,

134–135lymph vessels, 136odontoblasts, 127–129pulpal microvasculatures,

130–131pulp reaction to permeating

substances, 123–124regulation of pulpal blood

flow, 132–134stealing theory, 134transcapillary fluid flow, 135

Dentin thickness, after endodontictreatment

post/core, type ofprefabricated, 1452–1457

Dentistry, initial suggestions,549–550

Design aesthetics, operationsmanagement, 1484

branding, 1484–1485assimilation, program in

action, 1489–1490brand–customer relationship,

1491customer relationship, 1491developing culture of excellence,

basic steps, 1494enabling successful practice,

1484increased concern, case,

1484–1485

Index / 1519

office personality, 1488strategic development,

1489–1490strategic development/

foundation building/implementation,1489–1490

technology to operationalize,use of, 1487–1488

touchpoint overview, 1491–1494understanding, 1494–1495

creating a web site/stationary/brochure

web site, starting pointers, 1506customer satisfaction index,

1486, 1486femployee motivation and

morale, 1488–1489attitudes/retention, 1492brand-driven behaviors, 1489

goals, branding strategy, 1486HIPAA, 1492learning organization, existence,

1489NHII, 1487office design, 1483tpatient satisfaction surveys,

1495–1496TQM, 1496

‘‘quality in fact’’/’’quality inkind,’’ 1495

understanding satisfaction, 1495Diabetes, 762–763Diagnosiscase history, 407classification, 407

clinical classification ofcraniofacial pain, 407t

extracranial/intracranialpathema, 408

historychronic paroxysmal

hemicrania (CPH), 409general inspection, 410myofascial TrP pain, 409past medical, 410PHN, 408social, 410temporal patterns, 408

operant pain (pain behavior)somatization/malingering/

munchausen syndrome,414

physical examinationcranial nerve examination,

411, 411tinspection, 411, 423tlocal pathosis of extracranial

structures, 413tmyofascial TrP examination,

411psychogenic pain, 413

Diagnostician, requirementscuriosity, 521interest, 520, 521intuition, 521knowledge, 521patience, 521

Diagnostic studies, 412, 412tDiagnostic testinganesthetic test, 542

infiltration, 542dyes, 542–543

caries indicator solutions, 543felectric pulp testing. See Electric

pulp test (EPT)magnification, 542mobility, 539

Miller Index, 539palpation, 539–540

crown of tooth with cracklocated transilluminator,553f

toris mandibularis, 540PDL injection, 542percussion, 539periodontal probing, 541

double-ended instruments, 541Glickman classification

system, 541methylene blue dye, 541fvertical root fracture (VRF), 541

pulpal blood flow, measurement,544

system B hot pulp test tip, 537test cavity, 541–542thermal tests, 533–537

carbon dioxide snow, 535cold response, 534false negative, definition, 534solid CO2, applied on tooth/

tank, 536fwarm/cold, 535–538warm thermal technique, 537

tooth surface temperatures,measurement, 543–544

electronic thermography, 543Hughes Probeye 4300 thermal

video system, 543transillumination, 540

fiberoptic illumination, 541ultraviolet light, 544visual oral examination/review of

systems. See Visual oralexamination, diagnostictesting

Diaket, 1070Dialister invisus, 237Dialister pneumosintes, 237Differential scanning calorimetry

(DSC), 802–807, 804f,805f, 827

Digital Imaging andCommunication inMedicine (DICOM), 573,576, 579

Digital intraoral radiography,endodontic roots of, 574

Direct pulp cap, 1405treatment recommendations,

1320–1322vital pulp therapy

of mandibular left molar,radiographic/clinicalsequence, 1322

one-step pulp capping, 1322Discoloration, 11Doctor-Patient Relationship

(DPR), 86Dog pulp, 118fDoppler technique, 134Drainage through coronal access

opening, 706complex diagnoses, 707instrumentation, 707

magnification/illumination,enhanced, 707

trephination, 707Drug administration, comparison

of routes, 747tDrug–drug interactionsantibiotics and effects on oral

contraceptives, 781effect of oral contraceptives, 781effects of combination of drugs,

781patient’s response to, 780problems with higher levels of

combination of drugs, 782

1520 / Index

serious drug reactions withmacrolides, 782

unexpected effects of new drugs,781

Drug interactionschange in reactions, 781

by combination of drugs, 781increased/decreased effects,

781with food and herbals, decrease/

increase effects ofGinkgo biloba, 787Kava, 787Khat, 787Licorice, 788orange juice, 788other drugs, 787

Drug interactions and laboratorytests

with food and herbals, 787–788drugs prescribed by dentist

that may interact withherbal medicines, 802t

lab tests of potential importancein endodontics, 788–789

Drugs, banned, 781Drugs prescribed by dentists

interact with warfarinanticoagulant, 787f

DSC. See Differential scanningcalorimetry (DSC)

DSC heating (lower)/cooling(upper) curves, 803f, 804f,805f

D-speed film radiographs versusTACT, 582–583

DTA. See Dental Trade Alliance(DTA)

E

Echography, 309The Economics of Endodontics, 4Edentulism, 10Educational curricula and attitudes

of pediatric dentists,1423–1425

caries on primary incisors, 1424fEEO. See Equal employment

opportunity (EEO)Eikenella corrodens, 237Electric foramen locator, 929

Electric pulp test (EPT), 630Analytic Technology pulp tester,

538, 538fElectrocardiogram (EKG), 538patient placing finger lightly on

metal part of the probehandle, 538f

Electric pulp tester, 534, 547, 713Electronic apex locator (AEL)

accuracy, 844dual-frequency electronic apex

locators, 851–852high/low frequency apex

locators, 851multiple-frequency electronic

apex locators, 852–853resistance-based electronic

apex locators, 849–850voltage gradient apex locators,

851generations, first to fifth, 849parameters for use, 853

Electrosurgery/electrofulguration,1412–1414

comparing studies, 1413–1417Emergency surgical procedures

radiographic interpretation, 1285Emphysema, 1146

radiograph of lower left canine,1147f

swollen tissues, 1146, 1147fEmployee Retirement Income

Security Act (ERISA),1504

Enamel knot, 119Endodontics, 3–4, 12f

accessclinical methods, 153laboratory methods, 153

anxiety/fear problemmanagement, 738recognition, 737–738regulation, 739–740

areas, 37chronology, developments,

51t–52tclinical symptoms and lesions of,

origin, 1097fdefined, 1definition, 37DPR. See Doctor-Patient

Relationship (DPR)ethics/morals, 86–88

ethical basis for standard ofcare, 88

moral behavior, 88factors deciding retreatment, 1100fractured premolar restoration,

12ffrequency of claims, 86–87future of, 74historical stalwarts, 73–74informed consent, 87–94

AAE, 93definition, 92objective standard, 92

length determinationcontroversies in,1139–1140

malpractice, common elements,86t

miracle cures/pastes/mystery, 73anesthetics, 74irrigants, 73medicaments, 73obturation materials/

techniques, 74surgical materials/instruments/

techniques, 74non-surgical treatment, root

canal systems, 48–53periapical origin

differential diagnosis/treatment, oral pain inpulp, 43–46

etiology/diagnosis/prevention/treatment, pulp disease,40–43

morphology/physiology/human dental pulp,pathology/periapicaltissues, 37–40

periapical pathosis, surgicalremoval, 53–66

record keeping, 98–100SOAP format, 98

referrals, 100–103four general categories, 102subsequent radiograph, 100

scopes, 65standard of care, 88–91

controversy, 89definition, 88endodontic instrument, 89finformed/uninformed,

consent, 91

Index / 1521

instrument breakage, 89legal claims, role of, 88paresthesia, 91root canal filling, 89

vital pulp therapy, 46–48Endodontic abscesses/cellulitis,

treatment of, 692acrylic stint in place for

decompression, 699fantibiotics, 692–698

in endodontics, 693–695aspirate from abscess/cellulitis,

693fbiopsy from window consistent

with radicular cyst, 699fcapillary/penrose/rubber dam,

drain, 693fcollection of a microbial sample,

696conditions not requiring,

adjunctive antibiotics,694t

cortical trephination, 696–697,699f

decompression, aspiration andirrigation, 697–701

nasogastric tubing in cyst fordecompression., 700f

drain sutured in place, 692fhealed surgical window, 699fincision for drainage, 692–693needle aspiration, 692–694prophylactic antibiotics for

medically compromisedpatients

AHA, 695surgical window into cyst, 699f

Endodontically treated teethrisks associated with post-

retained restorations of,1200

Endodontic biofilms, 278–279Endodontic considerations in

dental traumaadjunctive therapy, 1350apical neurovascular damage,

effects, 1343–1345avulsed tooth, 1348–1352crown fracture, 1330–1332dental trauma, unique aspects,

1330endodontic essentials/treatment.

See Endodontics, essentials

hard tissue apical barrier,1337–1338

internal root resorption, 1352–1353luxation injury, 1347–1348pulp revascularization, 1338–1339

mature teeth, 1339root filling visit, 1351treatment. See also Dental

trauma, treatmentmethods

established external rootresoption, 1345–1347

nonvital pulps. See Nonvitalpulps treatment

root fracture complications.See Root fracturecomplications, treatmentof

vital pulp therapy. See Vital pulptherapy, traumatic dentalinjuries

Endodontic disease, microbiologyactinomyces, 262–263bacterial biofilms, 268–269

adoption of resistance,phenotype, 276–277

BCI. See Biomaterial-centeredinfection (BCI)

characteristics, 270communicate, exchange

genetic materials/acquirenew traits, 271

in dentistry, 277–278development, 271–273endodontic, 278–279extracellular polymeric matrix,

resistance, 276extraradicular microbial,

283–284growth rate/nutrient

availability, resistance, 276intracanal microbial, 279–283microbes to antimicrobials,

resistance, 273–275organized internal

compartmentalization,270–271

periapical microbial, 284–285protection from environmental

threats, 270ultrastructure, 269–270

diagnostic techniques,microbiological, 227–228

culture, advantages/limitations, 234–236, 230t

endodontic flare-ups, 266specific bacteria, endodontic

symptoms/associations,267–269

intracanal disinfectionprocedures, 241

microbes, association, 224–227outcome, bacterial influence,

241–243primary intraradicular

infections, 236–238Endodontic disease, primaryendodontic therapy, 626in mandibular first molar with

necrotic pulp, 648fosseous repair, following trauma,

648fEndodontic endosseous implants,

69–70Endodontic examinationapical diagnosis. See Apical

diagnosisclinical examination. See Clinical

examination, endodonticsdiagnostician, requirements of,

520history

chief complaint, 523medical history form, 521, 522tpresent dental illness, 523–525

pulpal diagnosis, 526Endodontic failure, 309, 1296,

1296fcause, 1125

Endodontic flare-upsage of patient, 701anatomic location, 701–702anxiety, 702gender, 701glossary, endodontic terms, 700inter-appointment pain, causes

of, 702mechanical/chemical injuries,

702obturation, 704preoperative history, tooth, 702pulp/periapical status, 702re-treatment cases, 703

swelling associated with flare-up following revision, 703f

systemic conditions, 701

1522 / Index

treatment of teeth, vital/non-vitalpulps, 702–703

treatment visits, number of, 702working length, 703–704

Endodontic flare-ups, treatment ofdiagnosis and definitive

treatment, 705–706Endodontic implants, 1298, 1299fEndodontic infections, 223–224

anachoresis, 225colonization, 223control of

host defense system, 992instrumentation and

irrigation, 992intracanal medicaments, 1009permanent root filling, 992,

1003interaction and characteristics,

1089fmicroorganisms, 238–240

archaea, 238fungi, 238virus, 238–240

missed canals, finding, 1100and MSDO, 631–635pathogenicity, 224polymicrobial interactions/

nutritional requirements,225–226

pulpal/periapical pathoses, 224virulence factors, 245–249

Endodontic instruments, 2, 89f, 814AAE, 814ADA, 814ANSI, 814barbed broaches, 823–824, 823fcutting blades, 814endodontic instrument

standardizationautoclaving, 814K-style modification, 815–816unused instruments, condition

of (comparisons), 815ffiles, 816–820

competing brands for cuttingability, comparison, 817

instrument breakages,Sotokawa’s classificationof instrument damage,819f

instrument fracture, cracksand deformation, 820f

fracture mechanisms, 943gates glidden modification, 823hand instrument conclusions, 823hedstrom files, retraction,

821–822H-style file modification, 822Quantec ‘files,’ 823reamers, 816tip modification, 820–821

H-style instruments, 821fU-file, 822

cross-sectional view, 822flightspeed instrument,

unusual, 822fmarketed names, 820–821

Endodontic panacea. See Calciumhydroxide

Endodontic patient, medicallycomplex, management of

adrenal suppression and long-term steroid use, 770

allergy to materials inendodontic therapy

antibiotics and analgesics,772–773

intracanal medications,cements, and fillingmaterials, 773–774

irrigating solutions, 773latex, 772local anesthetics, 770–772

assessing need for treatmentmodifications

multidimensional riskassessment model(MD-RAM), 752–754

bone marrow and solid organtransplantation

hematopoietic stem celltransplantation, 766–767

solid organ transplantation, 767cancer chemotherapy and

radiation therapy,765–766

bisphosphonate-associatedosteonecrosis of jaws, 766

cardiovascular diseaseanticoagulant therapy and

bleeding disorders, 761arrhythmias and cardiac

pacemakers, 761congestive heart failure,

762–763

diabetes, 762–763heart murmurs and valvular

disease, 757–760hypertension, 754–757ischemic heart disease,

756–767vasoconstrictor use in patients

with cardiovasculardisease, 755–756

central nervous system, 764–765human immunodeficiency virus,

768–769liver disease, 769medical consultations, 752medical history and patient

interview, 749–750medications and allergies,

750–751physical exam: vital signs, 751physical health status, 751–752pregnancy, 768previous dental treatment, 751prosthetic joints and other

prosthetic devices,767–768

pulmonary disorders: asthma,COPD, and tuberculosis,763–764

relative stress of plannedprocedure and behavioralconsiderations, 751

renal disease and dialysis, 765sickle cell anemia, 769

Endodontic–periodontal diseases,654, 654f

communication, main pathways,638

diagnosis for treatment andprognosis, 647

primary endodontic disease,647

primary periodontal disease,647

secondary periodontalinvolvement, 647–650

endodontic and periodontal, 638in mandibular first molar, 655fpresence and prevalence of fungi,

643–644role of bacteria, 641–644

Endodontic–periodontalinterrelationships

communication, 638

Index / 1523

apical foramen, 640dentinal tubules, 638lateral and accessory canals,

638–640contributing factors, 644

coronal leakage, 645developmental malformations,

646–647inadequate endodontic

treatment, 644root perforations, 646traumatic injuries, 645–646

dentin exposure, importance inprogression, 638

differential diagnosis, 647primary endodontic disease,

647with secondary periodontal

involvement, 647–650primary periodontal disease,

647secondary endodontic

involvement, 650–653prognosis, 654–656true combined diseases,

653–654etiological factors, 641

bacteria, 641–643fungi, 643–644viruses, 644

pulpal–periodontalinterrelationship, 640–641

Endodontic-periodontal lesion,608f

Endodontic procedures,nonsurgical

confined to root canal, 930Endodontic radiography, 554application of radiography to

endodontics, 554–556limitations of radiographs, 556

technology systems, 556–557cone positioning, 559diagnostic radiographs, 558extraoral film placement, 570film, 557horizontal angulation, 560horizontal cone angulations.

See Horizontal coneangulations

intraoral film placement,557–558

long cone, 557

processing, 570rapid-processing solutions,

570–571short cone, 557table-top developing, 571traditional machines, 557vertical angulation, 560working radiographs, 558–559

Endodontic retreatmentpreoperative radiograph of non-

healing maxillary centralincisor, 1094f

special concerns in, 1090Endodontics, digital imaging for,

573–574digital intraoral X-ray imaging

optionsdigital radiography, 576–577using secondary capture of

analog film images,574–576

radiation dose, 583–587working principles of digital

systemsadvantages of digital X-ray

imaging, 579conventional versus digital,

581detection of periapical lesions,

581–582detection of root canal

anatomy, 582–583digital subtraction

radiography, 583evaluation of assessment of

root canal length, 582examples of digital images

used in endodontics,579–580

solid-state systems, 577–578storage phosphor detectors,

578–579Endodontics, essentials, 1348concussion/subluxation, 1347extrusive/intrusive/lateral

luxation, 1347–1348treatment, 1350–1351

Endodontic sealers, 1068APEXIT, 1070bonding to gutta-percha and

dentin, 1072fcalciobiotic root canal sealer,

1069

kerr pulp canal sealer EWT, 1069rationale for use of sealers,

1068–1069roth’s 801, 1069SealApex, 1069–1070VITAPEX, 1070

Endodontics mode, 878accessing through crown,

disadvantages, 878areas in, use of lasers, 962–963existing restorations, advantages,

878Endodontic specialists, 3, 5f, 6f, 7fEndodontic studiesacceptable, relevant procedures,

1178categories, 1171

evidence-based practice, 1171minimizing bias in studies,

1171research design, 1170

confounding effects of differentvariables, 1179–1181

considerations specific to, 1179treatment differences in studies

on apical surgery, 1190variation in treatment

procedures, 1175–1177Endodontic surgeryanatomical considerations,

1235–1237anesthesia and hemostasis,

1237–1239adrenergic receptors in tissues,

1238beta-adrenergic effect, 1239objectives, 919osteotomy on mandibular

molar, 1238fperiradicular surgery, 1244vasoconstrictor, 1249vasopressor agents, 1237

corrective surgery. SeeCorrective surgery

emergency procedures. SeeEmergency surgicalprocedures

flap designand soft tissuemanagement. See Softtissue management andflap design

greater palatine foramen,opening of, 1235f

1524 / Index

historical perspectivesmicrosurgical endodontics,

1233specific indications, 1234

horizontal/vertical sulcularincisions, 1241, 1241f

implant surgery. See Implantsurgery

indications/contraindications/classification

endodontic surgery,contemporaryclassification of, 1234

palatal flap reflected andsutured, 1244f

periradicular surgery/treatment.See Periradicular surgery,treatment planning

rectangular flap to performperiapical surgery onmaxillary central andlateral incisors, 1242f

resection, root-end. See Root-end resections

scar (arrow) in gingival tissuesresulting from use ofsemilunar flap forperiapical surgery, 1243f

soft tissue lesion, 1250submarginal flap at time of

suture placement, 1244fsurgical outcomes. See Surgical

outcomestissue management

hard, curettage. See Hardtissue management andcurettage

soft, suturing/postoperativecare. See Soft tissuemanagement, suturingand postoperative care;Soft tissue managementand flap design

topical/local, hemostasis. SeeHemostasis, topical/local

triangular flap to performperiapical surgery

distobuccal root of maxillarymolar, 1241f

mandibular second premolar,1241f

Endodontic techniquesaspects of, 1198–1199

Endodontic therapyallergy to materials used in, 770,

771fanticipating the future, 29case representation, 10–12

considerations, 16indications, 12–15oral conditions, 16–21

changeattitudes, 4endodontics, 3–4instrument design/

standardization, 2–3nomenclature, 1–2

endodontics, controversiesapical patency and its

preparation, 28–29apicalterminus and cleaning

apical patency, 25–28postoperative pain, 23single-appointment therapy,

21–23success versus failure, 23–25

factors influencing post removaland heat transfer,1136–1138

future, as speciality, 4–10inadequate radiograph of

mandibular first molar withcrown, screw post, 1115f

mishaps and seriouscomplications of

factors influencing postremoval and heat transfer,1135–1137

thermal injury with use ofultrasonics, 1135–1136

past/present, future prologue,29–30

post insufficient, 1097fthermal injury with use of

ultrasonics, 1135–1136transforming advances

saliva, diagnostic/informativefluid, 30

tissue engineering, 30tooth regeneration, 30–31

Endodontic therapy, primary teethcomparison of primary and

permanent toothanatomy, 1400–1402

diagnosis of pulpal pathosis inchildren, 1416

educational curricula andattitudes of pediatricdentists, 1423–1425

electrosurgery/electrofulguration,1412–1414

ferric sulfate, 1259–1260formocresol, 1406–1411freeze-dried bone, 1412glutaraldehyde, 1411–1412lasers, 1414–1415medical factors in determining if

a primary tooth should besaved

contraindications, 1460–1461mineral trioxide aggregate, 1030nonvital pulp therapy for

children, 1417–1423pulpotomy, 1406treatment of deep caries: indirect

pulp therapy, 1403–1405vital pulp therapy for children:

direct pulp cap,1332–1333

Endodontic therapy and mishapmanagement, retreatmentof non-healing, 1088

air emphysema, 1146blocks, ledges, and apical

transportations, 1122techniques for managing apical

transportations, 1123–1125techniques for managing

blocked canals, 1122–1123techniques for managing canal

ledges, 1123carrier-based gutta-percha, 1141coronal leakage and prognosis

for healing, 1091–1093armamentaria and techniques

associated with missedcanals, 1097–1100

coronal disassembly, 1095coronal disassembly devices.

See Coronal disassemblydevices

factors influencing restorativeremoval, 1095–1096

non-surgical versus surgicalretreatment, 1095

technology of retreatment,1094–1095

temporary coronalrestorations, 1093–1094

Index / 1525

damage to neurovascularanatomy: causes andoutcomes, 1141–1142

diagnosis and management ofinferior alveolar nerveinjury, 1142–1143

management of inferioralveolar nerve injuries,1143–1144

fractured instrument removal,1114–1115

coronal and radicular accessfor, 1116–1117

creating a staging platform,1117

factors influencing, 1136–1137removal using microtube

system, 1120–1121techniques for, 1122ultrasonic techniques for,

1117–1119length determination

controversies inendodontics, 1139–1140

mishaps and seriouscomplications ofendodontic therapy

factors influencing postremoval and heat transfer,1136–1138

thermal injury with use ofultrasonics, 1135–1136

NaOCl accident, 1145causes of NAOCL accident,

1145management, 1145–1146prevention, 1146

obturation and irrigationmishaps, 1137–1138

anatomic and imagingcharacteristics of inferioralveolar canal, 1138–1139

anatomic and imagingcharacteristics ofmaxillary sinus, 1138

importance of accurateradiographic imaging, 1138

perforation and prognosis forhealing, 1125

barrier materials for perforationrepair, 1130–1131

clinical considerationsinfluencing perforation

repair based on evidence,1129

esthetics and perforationrepair, 1130

hemostatics for perforationrepair, 1130

location of perforation,1127–1128

MTA for perforation repair,1129

perforation repair materials,1128

periodontal condition andperforation repair,1129–1130

restorative materials inperforation repair, 1131

size of perforation, 1128techniques for perforation

repair, 1131–1135timing of perforation repair,

1125–1127treatment sequence for

perforation repair, 1130vision and perforation repair,

1130post removal, 1110

factors influencing, 1110mechanical devices,

1112–1114techniques for, 1110–1112

post-treatment infection of rootcanal system

disease factors, 1088–1089previous root canal treatment,

1089prevention of obturation

mishaps, 1144–1145removal of obturation materials,

1100gutta-percha, 1131,

1138–1389. See alsoGutta-percha (fillingmaterial), removal of

microtube removal options,1105–1107

paste removal, 1108–1110Resilon, 1103silver points, 1065

risks versus benefits, 1089benefits, 1089–1090patient considerations,

1090–1091

risks, 1090special concerns in endodontic

retreatment, 1090techniques for obturation control

when neurovascularproximity exists, 1140

thermoplasticized gutta-perchaand effects of heat,1140–1141

Endodontic treatmentaim and asymptomatic function,

1165consent, 530–531

ameloblastoma, 100fdisinfecting agents

Ca(OH)2, 1009CHX, 1002hydrogen peroxide, 1388NaOCl, 997–1002

and increased susceptibilityfracture, 920f

internal resorption, 601flocal contraindications, 48fnon-surgical, 643fpersistent disease after

re-treatment, 1174freplacing pulp tissue, 921re-treatment in conjunction with

internal perforationrepair, 1196f

role of radiograph, 574root-end management with

bonded composite resin,1177f

success of, 573Endodontic treatment failure,

microbes, 257–258Endodontic treatment outcome,

1173ambiguity of outcome definition,

1162–1165consequences of using terms

‘‘success’’ and ‘‘failure,’’1163–1165

lenient definition of ‘‘success,’’1163

outcome definition as‘‘uncertain,’’‘‘questionable,’’‘‘doubtful,’’ or‘‘improved,’’ 1163

strict definition of ‘‘success,’’1163

1526 / Index

antibacterial efficacy of intra-canal procedures, 1200

apical enlargement, 1201dressing with medication,

1200–1201factors influencing healing

after apical surgery, 1201irrigation, 1200

apical periodontitis, teethtreated with associated,1187

dynamics of healing,1199–201

functional teeth, 1184healed teeth, 1184–1189healing in progress, 1188

apical periodontitis, teeth treatedwithout associated

dynamics of developingdisease, 1184–1187

functional teeth, 1188healed teeth, 1190

apical surgery, potential forhealing and retainedfunction after, 1190

dynamics of healing, 1191functional teeth, 1191healed teeth, 1187–1188healing in progress, 1188

appraisal of endodontic outcomestudies, 1171–1181

exposure (treatment,intervention), 1175–1178

outcome assessment,1187–1179

reporting of data and analysis,1179–1181

appraisal of studies, 1171–1175appraisal of studies, general

considerations, 1170–1171dynamics of developing disease,

1184–1187evidence-base for outcome of

endodontic treatment,1165–1170

radiographic outcomeassessment, 1162

selected studies comprising‘‘best’’ evidence, 1181

potential for healing andfunction afternonsurgical treatment,1192–1194

teeth treated withoutassociated apicalperiodontitis, 1181–1183

Endogenous opioid system, 382pain modulation

endogenous opioid peptides,398

pain suppression, 398Endo-Rez, 1072Endoscope visual system (EVS), 873fEndoscopic sinus surgery

rhinosinusitis, 629Endosseous root form implants,

1298Endotoxin, 1103Enterococcus, 258–260

prevalence in endodonticinfections, 259t

Enterococcus faecaliscells, 999fsamples of, 996f

Enterococcus faecalis, 227Enzyme-linked immunosorbent

assay (ELISA), 1028Epinephrine

containing local anesthetics andall drugs, 786t

Epiphany, 1073sealer, 1028f

Epoxy resin sealers, 1035–1037Epstein–Barr virus (EBV), 238EPT. See Electric pulp test (EPT)Equal employment opportunity

(EEO), 1497Equipment, rubber dam, 791

adjuncts to rubber damplacement, 796

plastic/cement instrument/dental floss, 796

clamps, 795variety, 795fwinged clamp/wedjets cord,

796fdam material, 791–792forceps, 795–796

rubber dam clamp selection,795t

frame/dam combinations, 794fframes, 792–795hinged rubber dam frame, 794flatex-free barrier/U-shaped

Young’s rubber dams, 793fpunch, 792

swallowed endodontic file inappendix resulting inacute appendicitis, 792f

Erbium:YAG laserremoval of debris, effective, 963,

964fERISA. See Employee Retirement

Income Security Act(ERISA)

Escherichia coli, 232Ethylenediaminetetraacetic acid

(EDTA), 1075citric acid and other acids,

1000–1002Etiological factor of apical

periodontitis, bacteria,990

Eubacterium, 226Extracellular matrix (ECM), 127,

129Extraction/alveolar preservation

allograft hydroxyapatite, 1303fatraumatic extraction, 1302f

Extraction/implant placement,immediate

atraumatic extraction, 1302ffinal drill, surgical template,

1304fgrafting the gaps, implant/bone

walls, 1305fhorizontal root fracture, 1304f

Extraradicular infections,endodontics, 243–244

apical actinomycosis, 243Extraradicular microbial biofilms,

283–284, 283f

F

Fair Labor Standards Act (FLSA),1504

Federation Dentaire Internationale(FDI), 1036

Ferric sulfatecomparing with formocresol

pulpotomies andinference, 1429–1430

internal resorption in a primarymolar, 1416f

Fiber optic endoscope (orascope),873, 873f, 874f

fogging, 873

Index / 1527

Fibrefill, 1073Fibroblast, 127Fibronectin, 355Filifactor alocis, 237Fillinggutta-percha versus Resilon, 1065flateral canal, significance of,

1075, 1075fsuccess/failure of root canal

therapy, 1056twith and without radiography,

clinical success of, 1055tFilm, X-ray machine, 559film placement

extraoral film placement, 571intraoral film placement,

557–558teeth, 568f

hemostat, 558fadvantages, 561

holder, 558fprocessing, 571

rapid-processing solutions,570–571

table-top developing, 571‘‘Finger-powered’’ instruments, 3First molar, 14fFixed partial denture (FPD),

105–106Flaring apex, 22FLSA. See Fair Labor Standards

Act (FLSA)Focal infection theory, 221–223Food–drug interactions, 775Foreign body reactionnonmicrobial aspects of disease

accumulation of cholesterolcrystals, 325

cystic lesions, 320–321root canal filling, 328scar tissue healing, 336–337

Formocresol, 1417caries removal, 1407fplacement of zinc oxide, 1408fprimary molar with stainless steel

crown, 1408fpulpotomy in primary teeth,

1408fremoval of roof of pulp chamber

and coronal pulp, 1407fstudies on, 1421–1424

Fractured instrument removal,1115–1116

challenge to remove broken Ni-Ti file, 1130

coronal and radicular access forinstrument removal,1116–1117

factors influencing fracturedinstrument removal,1115–1116

File Adapter, 1119staging platform, 1118

Gates Glidden drills, 1117fgraphic representation of,

1117ftechniques, 1128Titanium instruments,

1117–1119, 1118fultrasonic preparation, 1118ultrasonic techniques, 1117–1120

design of, 1128–1129direct contact with obstruction

and activation, 1118use of piezoelectric ultrasonic,

1128using a microtube system,

1120–1121creating potential for

instrument retrieval,1120f

Freeze-dried boneinference, 1478

Furcation perforation, 1127Fusobacterium nucleatum, 237Fusobacterium periodonticum, 237

G

Galilean optics, 871fGates Glidden (GG) burs, 880,

1117fGeneral mental ability (GMA),

1501General practitioners (GPs), 113Gene-targeting experiments, 119Genetic polymorphism, 343Gene transfer systems, 249antibiotic resistance/virulence,

with plasmids, 252horizontal gene pool, 249–252pheromone-initiated conjugative

transfer of plasmids, 252GFR. See Glass fiber-reinforced

epoxy resin (GFR)

Giant cell granuloma, 615fGinkgo biloba, 749Glass fiber-reinforced epoxy resin

(GFR), 1453–1455,1454–1455f

Glass ionomer repairperforation repair, 1128

Glass ionomers, 1042Glickman classification system,

periodontal probing, 541Glutaraldehyde, 1411–1412GMA. See General mental ability

(GMA)Granulomas, 595–597Grossman’s sealer, 1038, 1069,

1072. See also Zincoxide–eugenol-containingsealers

Growth factorbone regeneration, 361classifications, 360t

Guarded enthusiasm, 31Gutta-balata, 1028. See also Gutta-

perchaGutta-percha delivery system,

thermoplasticizedCalamus system, 1024–1025,

1025felements system, 1024fUltraFil system, 1025

Gutta-percha (filling material),1066

biological objectives, 933carrier-based, 1025–1027, 1141

Densfil, 1025errors in technique, 1141removal, techniques used for,

1100–1107SimpliFil, 1027, 1027fSuccessFil, 107

chlorhexidine, 1021composition, 1020tdesign objectives for cases to be

filled with, 932disintegrated, 329fenterococcus faecalis, 1021giant cells within apical

periodontitis, 332finject-R fill, 1062lateral/vertical compaction of,

1062undesirable stress

concentration, 1063

1528 / Index

nickel–titanium versus stainlesssteel spreaders, 1058

observation in lateral grooves,1075f

perforation repair withphosphate cement, 1131

plastic-embedded semithin ofapical area, 331f

properties, 1027–1028removal of, 1111–1112

carrier-based, 1107–1108heat and instrument, 1102paper point and chemical

removal, 1102–1103rotary instrumentation,

1100–1102, 1108fultrasonic, 1102

versus Resilon, 1064froot-filled and periapically

affected left centralmaxillary incisor, 330f

root filling in split tooth modelwith straight and roundcanal, 1062f

sodium hypochlorite, structuraleffects, 1023

stereochemical structure, 1021fsystem B plugger technique,

1061–1062thermomechanical compaction,

1025MicroSeal System, 1022–1025

thermomechanical compactionof, 1060

thermomechanical solid core, 1060thermoplasticized, 1023–1024

and effects of heat, 1140–1141injectable, 1061

tissue reaction to, 328fultrasonic plasticized, 1060–1061vertical versus lateral, 1062–1063

Gutta-percha point, 90f

H

Hard tissue apical barriercrown-root fractures, 1339filling of root canal, 1338

‘‘Swiss cheese’’ consistency,1338

horizontal root fractures, 1339treatment, 1341

MTA barrier, 1337–1338apexification, successful,

1337fpulp revascularization,

1338–1339immature tooth, necrotic

infected canal with apicalperiodontitis, 1346f

reinforcement of thin dentinalwalls, 1338

traditional method, 1337Hard tissue deconstruction,

mechanism of, 1361Hard tissue management and

curettagebony window of adequate size to

perform periapicalsurgery on mandibularpremolar, 1250f

bur, shape, 1249fcurettage of inflammatory soft

tissue, 1251curettage of soft tissue lesion

allows for visualization ofmesiobuccal root apex,1251f

osseous tissue response, surgicalremoval, 1249

root end located followingcareful osseous removal,1249f

root surface distinguis, 1253HBD. See Hypophosphatemic

bone disease (HBD)H&D curve, 585, 586, 586fHealing, perforation and prognosis

for, 1125barrier materials for perforation

repair, 1130–1131clinical considerations

influencing perforationrepair based on evidence,1129

esthetics and perforation repair,1130

hemostatics for perforationrepair, 1130

location of perforation,1127–1128

MTA for perforation repair,1129

perforation repair materials,1128

periodontal condition andperforation repair,1129–1130

restorative materials inperforation repair, 1131

size of perforation, 1128techniques for perforation repair,

1131–1135timing of perforation repair,

1125–1127treatment sequence for

perforation repair, 1130vision and perforation repair,

1130Health Insurance Portability and

Accountability Act(HIPAA), 1488

Heart murmurs and valvulardisease, 757–760

antibiotic prophylaxis for dentalprocedures, 759f

antibiotic prophylaxisrecommended, 758f

increased risk for infectiveendocarditis, 757

risk of dental procedures, 758fHematogenous total joint infection,

767fHematopoiesis of immune cells,

344Hemostasis, topical/local, 1258

bone wax, 1258calcium sulfate, 1260collagen products, 1260ferric sulfate, 1259gelfoam/spongostan, 1260microfibrillar collagen hemostat,

1260–1261racellet container and pellets,

1258root-end filling materials,

1261–1266surgicel, 1261thrombin, 1260vasoconstrictor-impregnated

cotton pellets/sponges,1258–1259

Hemostasis, vital pulp therapy,1319–1320

enterococcus, faecalis, 1320evaluation, clinical/short-term,

1319importance, 1319

Index / 1529

irreversible pulpitis, 1319NaOCl

advantages of, 1319recommendations, 1320

Hemostat, straight, 558, 558fadvantages, 559

Herbal medicine–drug interactions,780

Hermetic, 1053. See alsoImpermeable seal

Heterogenous nature of dentintubular, 122f

HIPAA. See Health InsurancePortability andAccountability Act(HIPAA)

Histopathology of periapicallesions of endodonticorigin

‘‘abscess theory,’’ 506acute apical abscess, 500, 508

apical granuloma, 501fepithelial strands in apical

granuloma, 505fapical cyst, 506, 506fapical scar, 508–509asymptomatic apical

periodontitis, 507cellulitis, 508chronic apical abscess, 508condensing osteitis, 508normal periapical tissues, 507nutritional deficiency theory, 506symptomatic apical

periodontitis, 507true cysts, 506

Historical stalwarts, endodontics,73–74

Homeostasis phenomenon of pulp,periodontal ligamentpreventing osteoclasticattacks, 1358

Horizontal cone angulations, 560mandibular anterior teeth,

568–569mandibular molars, 560–565mandibular premolars, 565–566maxillary anterior teeth, 569–570maxillary molars, 566–567maxillary premolars, 567–568

Host defense, 1011Human cytomegalovirus (HCMV),

238–240

Human immunodeficiency virus,768–769

Human pulp, 126fHuman resources, operations

management inendodontics

confidentiality/non-competitioncovenants, 1507

dental assistant wages, 1504tEEO, 1497employee benefit and salary

administrationERISA, 1504FLSA, 1504HIPAA, 1504

employee handbook, suggestionsfor creation, 1499–1501

standard operatingprocedures: computers,1500t

employee notices, posting, 1503employee selection criteria,

1501–1502GMA, 1501

employment law, 1505–1507law issues, 1506suggestions, avoid common

legal pitfalls, 1506employment liability practices

insurance, 1507hiring best person for job,

1502–1503areas to avoid, interviews,

1503job description, 1497management program, elements,

1497staff meetings and peak

performance, 1507–1508standard operating procedure

(SOP), 1497–1499tasks/knowledge/ability tasks,

1498t–1499ttermination, 1504–1505

factors, preserve objectivity,1505

workers’ compensation, 1507Hurter and Driffield curve. See

H&D curveHydrogen peroxide, 1002Hygroscopy, desiccation by, 483Hyperparathyreoidism, primary,

616f

Hypersensitivity reactionsinnate, 368types, 367–368

Hypertension, 754–755blood pressure classification,

755fHypophosphatemic bone disease

(HBD), 487

I

IASP. See InternationalAssociation for the Studyof Pain (IASP)

Iatrogenic effects, dental pulp,479–482

‘‘blushing,’’ 480cavity cleansing, 481

dentin-enamel junction (DEJ),481

etching dentin/smear layer,481

cavity/crown preparationheat

cutting dentin, 480experimental observations,

480laser beams, 481

tooth structure, safepreparation, 481

crown cementation, 482dental materials, 482

desiccation by hygroscopy, 483heat upon setting, 482microleakage/cytotoxicity, 482

impressions and temporarycrowns, microleakage,482

local anesthetics, 479pins, 481

Iatrogenic perforationsmanagement, 1144setting of MTA and required

treatment, 1124fIdiopathic osteosclerosis, 608IHS. See International Headache

Society (IHS)Imaging Plate, 573–579Immune complex reactions,

367–368Immunological methods, 230Immunologic reactions, 367

1530 / Index

Impermeable seal, 1053Implant fracture, esthetic, 1307Implant surgery

endodontic endosseous implants,1294

osseointegrated implants, 1295Incisive canal cyst, 613fIndirect pulp therapy, 1425Inferior alveolar nerve (IAN), 714Inflamed dental pulp

acute inflammatory process, 381Inflammation, 344Inflammation and immunological

responses�-defensins, 348cells of adaptive immunity,

348–351cells of innate immunity, 344–348cytokines

proinflammatory cytokines,356–358

systemic effects of, 358growth factors, 360–361hypersensitivity reactions,

367–368inflammation-induced bone

resorptioninhibition of bone resorption

by bisphosphonates, 366mechanisms of bone

resorption, 364–365microbial role in pathogenesis

of periradicular lesion,363

role of immune cells inperiapical lesionformation, 364

roles of cytokines inperiradicular boneresorption, 366–367

innate and adaptive immunesystems, 344–345

MHC and antigen presentation,351–352

molecular mediators of anti-inflammatory reactions

anti-inflammatory cytokines:IL-10, TGF-�, IL-4, andIL0–0, 362

membrane phospholipids/arachidonic acidmetabolic pathways,361–362

NF-kB and NF-kB-activatingpathways, 362–363

molecular mediators ofproinflammatoryresponse

adhesion molecules, 352chemokines, 352plasma proteases, 353

coagulation cascade andfibrinolytic systems, 354

complement system, 354kinin system: bradykinin,353

matrix metalloproteinases,354–355

neutrophil elastase, 355platelet-activating factor, 352

neuropeptides, 358–359nitric oxide, 355oxygen-derived free radicals,

355–356toll-like receptors, 359–360

Inflammatory mediators, 383Inflammatory response, 343, 352,

353, 353f, 357, 358, 468Infraorbital nerve block injection,

721Ingle’s MBD rule, 561, 564, 935Inhibition of bone resorption by

bisphosphonatesmechanism of bisphosphonate

(BP)-induced, osteoclastapoptosis, 366, 365f

Innate immune system, 344phagocytosis, 345

Innate immunity, cells ofcomparison of mast cells and

basophils, 347tdendritic cells (DCs) and NK

cells, 347–348eosinophils and basophils, 347odontoblasts, 348PMNs and macrophages,

346–347Instrumentation and irrigation, 242Instrumented and uninstrumented

root canal wall afterirrigation, 1000f, 1001f,1007f

Instrument Removal System (iRS),1107, 1108f, 1120, 1121

clinical case utilizing, 1120fInsular cortex (IC), 398

Intact coronal structure, 1296Intentional replantation, 1220–1221Intentional teeth replantation, 67–69Interactions, microorganisms,

249–257antibiotic resistance and

virulence associated withplasmids, 252

cooperative/antagonistic,253–254

extra-chromosomal DNA,horizontal gene pool,249–252

gene transfer systems, 249pheromone-initiated conjugative

transfer of plasmids, 252plasmids in oral and endodontic

microflora, 253species-specific interactions,

microorganisms in rootcanal infections, 254–256

International Association for theStudy of Pain (IASP), 393

International Headache Society(IHS), 426

International StandardsOrganization, 573

Interradicular periodontal lesions, 69Intracanal disinfection procedures,

241Intracanal irrigation, 696Intracanal medicaments containing

antibiotics, 1011Intracanal medications, cements,

and filling materials,772–773

Intracanal microbial biofilms,279–283, 279f

Intranasal drug (IN drug), 746Intraoral X-ray sensors, diversity

of, 575fIntravenous conscious sedation,

743–745Iodine potassium iodide, 1006IRM, 1043Irrigants and intracanal

medicaments, 992alternatives for interappointment

medicamentsintracanal medicaments

containing antibiotics,1011

phenol compounds, 1011

Index / 1531

developments in root canaldisinfection, 1009

effect of instrumentation on rootcanal microbes, 993–994

elimination of microbes in rootcanal system, 992–993

goal of endodontic treatment, 993infection control in human body,

992instrumentation of root canal,

985intracanal interappointment

medicamentsCa(OH)2, 1006–1007CHX, 1002–1006

physical means of canal cleaningand disinfection

lasers, 1008–1009ultrasonic cleaning, 1007–1008

root canal disinfection bychemical means

antibacterial irrigatingsolutions, 997

CHX, 995–1003EDTA, citric acid and other

acids, 1000–1002hydrogen peroxide, 1002iodine potassium iodide, 1006NaOCl, 997–1001

antibiotic-containingirrigation solutions

MTAD and tetraclean,1006–1007

challenges, 994ex vivo and in vivo models,

995–997in vitro models, 994–995

Irrigating solutions, 771Irrigation dynamics, 967–968effect of sizes and canal

diameters needle position,967f

irrigation performance and sizeof needle, 968

Ischemic heart disease, 756–758treatment modification, 757

J

Japaneseand one appointment therapy, 21

Journal of Endodontia, 36

K

Kava, 787Kerr Broach, 2fKerr pulp canal sealer EWT, 1069Ketac-endo, 1071Khat, 787

L

Lactobacillus casei, 245Lamina dura, 564–566Laser-assisted canal preparation,

962–964limitations of, 964removal of debris using

erbium:YAG laser, 989feffective, 990f

shaping of single rooted teeth,989f

use in endodontics, 968Laser beam, 857–861Laser doppler flowmetry (LDF),

859applications. See Applications of

LDF, dentistrylaser Doppler setup, example, 548fpotential modalities, 551–552technology, development and

principle, 547Fast Fourier Transform (FFT)

analysis, 548laser Doppler machine,

readout, 563fuse and development, 552

Laser in endodonticsapical surgery, 865–866

preparation of apical cavities,Er:YAG laser/ultrasonics,866

cleaning/disinfecting, root canalsystem, 860–864

intra-canal use of lasers,limitations, 861

endodontic retreatment, 865laser interactions, basic types,

874flaser irradiation, 878fobturation, root canal system,

864–865thermoplasticized compaction,

concept, 864

parameters, while operatinglaser, 874f

principles of operationLASER beam, 857–859‘‘surgical’’ beam, 857

pulpal diagnosis, 859LDF, 859

pulp capping/pulpotomy,859–860

mineral trioxide aggregate(MTA), 1030–1033

radiograph, vertical rootfracture, 879f

schematic diagram of laser, 873fwavelengths, laser types

according to emissionspectra, 873f

Lasers, 1428compared with four pulpotomy

techniques, 1415in endodontics, 1005–1006

Lasers in Endodontics, 857Lateral canalsclinical aids for identification,

640detection, 640vessels, 131f

Latex, use of, 770LDF. See Laser Doppler

Flowmetry (LDF)LDF technology, development/

principle, 547–549Licorice, 787LightSpeed (LSX), 944Lightspeed NiTi rotary instrument,

805Limited liability company (LLC),

1481Limited liability partnership (LLP),

1481Lipopolysaccharide (LPS), 224,

245–246, 468Lipotechoic acid (LTA), 246–247,

468Liver disease, 769LLC. See Limited liability

company (LLC)LLP. See Limited liability

partnership (LLP)Loading protocol, immediateadditional requirement, 1306advantages, 1315

Local anesthetics, 768

1532 / Index

and all drugs, 783EPT, 714preliminary factors, clinical trial

literature, 713Loupes, visual enhancement

single/multi lens loupes, 870Low-compliance system theory,

135LPS. See Lipopolysaccharide (LPS)LPS-binding protein (LBP), 346LTA. See Lipotechoic acid (LTA)Luxation injuries

definitionsconcussion, 1347direction, 1342extrusive, 1342lateral luxation, 1347subluxation, 1353

trauma, types, 1354external/internal inflammatory

root resorption, 1343

M

Macrolidespotential reactions between

macrolide antibiotics andall drugs, 783t

Macrophage colony-stimulatingfactor (MCSF), 365

Macrophages, 327activation and function, 346f

Macrophages release somatostatin(SRIF), 502

Major histocompatibility complex(MHC), type II, 470

Malignant tumors in jaws, 617Malpractice/negligence, common

elements, 86tManagement (winning) practices,

operations managementin endodontic practice

focusing matrix, 480tmeasuring customer defections,

1479tprimary, 1479–1480secondary, 1480

Mandibular anesthesia, 714–716adverse effects, 722articaine, 715bidirectional rotation method,

716

IAN block injections, 716factors, for success, 717lack of success, 716reasons, lack of success, 716

intraligamentary injection,supplemental, 717–718

effects, potential adverse, 717intraosseous

anesthesia delivery systemX-tip, 737f

characteristics, 718–720stabident system, 718

intrapulpal injection, 720long-acting local anesthetics, 715mepivacaine, 715prolonged pain control, 715ropivacaine, 716time-response curve,

development of pulpalanesthesia, 712f

VGSC, 716Mandibular anterior teeth

horizontal cone angulations,560–570

horizontal X-ray projections, 583fprojecting directly through

canine, 584fMandibular canines

anatomy and morphology,909–913

versus mandibular incisors,912

canal system, 188, 188tclinical, 913–914external root morphology,

191–192labial and mesial view, 194fmesial curvature of root in

apical third, 196f1 root and 1 wide canal, 195froot cross-sections, 195f

labial, mesial, and incisal views,933f

root number and form, 193, 193tsimilarity to maxillary incisors,

930ftreatment sequence of two canals

in, 934fvariations and anomalies, 197

dens invaginatus, 197, 198ffusion, 191gemination, 197, 198fpresence of two canals, 191

radicular third rootbifurcation, 196f

two canals and two roots, 194Mandibular central incisor

canal system, 181–183number of canals and apices,

179shape, 184

external root morphology, 184labial and mesial view, 185froot cross-sections, 185f

length of, 184versus mandibular lateral incisors

exihibiting fusion, 188fnumber of canals, 183t

root number and form, 1841 root and 1 canal, 186f

two canalsconnecting apical third web-

canal and one apicalforamen, 187f

and one apex, 187ftwo separate apical foramina,

188fvariations and anomalies, 186

dens invaginatus, 184fusion, 188fgemination, 188–189, 189f

Mandibular first molarsachieving SLA, 939fanatomical variations in, 940fanatomy and morphology,

915–916canal system, 210

three-rooted, 205ttwo-rooted, 209t

clinical, 919–921distal canal, 915external root morphology,

205–206buccal and mesial, 209f, 210froot cross-sections, 210f2 roots and 3 canals, 210f, 211f

length of, 206with periapical lesion, 1165fpresence and impact of furcation

canals, discussion, 915root and root canal anatomy

of distal root, 932tof mesial root, 932t

root number and form, 209–210Mongoloid versus non-

Mongoloid, 206–208

Index / 1533

number of roots, 208tsearching middle mesial canals,

939, 940fvariations and anomalies,

209–210extra canal, 213fsupernumerary roots and

canals, 213f, 214ftaurodontism, 214f

Mandibular first premolarsanatomy and morphology, 909bifurcated teeth, 193buccal, mesial, and occlusal

views, 935fcanal system, 201–202

number of canals and apices,204t

clinical, 915external root morphology,

191–193buccal and mesial view of, 199froot cross-sections, 200f

length of, 198versus mandibular second

premolarnumber of canals and apices,

204tseparate canals, 209

removal of more buccal cuspthan lingual, accesscavity, 936f

root and root canal anatomy,912t

root number and form, 203main buccal and vestigial mid-

root lingual root, 195fsingle root and single canal,

194f, 195fTome’s root, 193two root canals, incidence,

199–200variations and anomalies, 200

rare three-rooted, 202fthree canals and two roots,

196, 196fthree canals in single root, 196,

196fMandibular incisorsanatomy and morphology, 909buccal and lingual canals with

separate apical foramina,916f

clinical, 909

fin or groove with pulp tissuebetween them, 928f, 910

labial, mesial, and incisal views,890f, 905f

root and root canal anatomy,912t

Mandibular lateral incisorscanal system, 191t

shape, 191two canals and one apical

foramen, 192fexternal root morphology, 187

labial and mesial view, 188froot cross-sections, 189f

length of, 187root number and form, 187–188,

190t1 root and 1 canal, 190f1 root and 1 canal with

multiple lateral canals,190f

separation of single canal into2 canals, 190f

variations and anomalies, 191dens invaginatus, 191fusion, 192, 193fgemination, 192, 193f

Mandibular molarsaccess preparations, 918f, 938f

moderate/severe rootcurvature, 937f

buccal mesial occlusal views,936f

four canals, 578fhorizontal cone angulations,

560–570hourglass-shaped canal, 579fand lamina dura, 565–566lingual and mesial inclination of,

880‘‘opening up’’ roots, 571froot canal-treated, 928fstandard horizontal X-ray

projection, 561fMandibular premolarsfirst premolar, 580fhorizontal cone angulations,

560–570Mandibular second molars, 209anatomy and morphology, 915canal system, 213–215

two-rooted teeth, 216, 209tclinical, 921

C-shaped canals, 915external root morphology, 205

buccal and mesial view, 214froot cross-sections, 215f2 roots and 3 canals, 215f, 216f

length of, 216root number and form, 206, 208tvariations and anomalies, 209–210

additional canals, 218fC-shaped canal, 216fused or single roots, 209, 210ftwo canals, 210f

variations in anatomy, 926fMandibular second premolarsanatomy and morphology, 915buccal, mesial, and occlusal

views, 928fcanal system, 208–209, 208t

incidence of two or morecanals, 200

clinical, 915external root morphology,

202–203buccal and mesial view, 205froot cross-sections, 205fsingle root and single canal,

194flength of, 203, 205root number and form, 205t, 206variations and anomalies, 205

dens evaginatus, 200, 200ftwo canals, 200, 201ftwo roots, 208

Mandibular third molarsanatomy and morphology,

915–916clinical, 922

Master apical file (MAF), 880Matrix database elements,

diagnostic software(AEL), 850f

Matrix metalloproteinase (MMP),127, 354, 355t

Maxillary anesthesiaanterior middle superior alveolar

(AMSA), 721infraorbital nerve block

injection, 721palatalanterior superior alveolar

(P-ASA) injection, 721Maxillary anterior teethhorizontal cone angulations,

560–561

1534 / Index