11 myths of dentoalveolar surgery

JADA, Vol. 129, September 1998 1271

Paul Broca (1824 to 1880) once stated, “The least questioned as-sumptions are often the most questionable.” This is certainly true ofsome surgical beliefs that have been passed orally and in writingfrom one generation of dentists to another through the years. Theseso-called facts sometimes began as statements in textbooks that arenow outdated, while others originated from mentors sharing anec-dotal experiences with students. These pseudoscientific statementsare accepted without question by many general dentists and spe-cialists performing surgical procedures.

Physicians and dentists alike are becoming increasingly interest-ed in teaching and practicing evidence-based medicine. This hasbeen defined as the conscientious, explicit and judicious use of cur-rent best evidence in making decisions about patient care, ratherthan relying solely on intuition and experiences.1,2 This has beenshown to be a desirable approach to integrating clinical expertisewith the best available evidence obtained from systematic research.In this article, I will examine 11 myths that are commonly encoun-tered in the field of dentoalveolar surgery and show that each lacksclinical importance or is based on anecdotal beliefs without support-ing scientific evidence.

MYTH NO. 1: PEOPLE WHO USE ASPIRIN WON’T STOPBLEEDING AFTER SURGERY

Aspirin (that is, acetylsalicylic acid) was first marketed by Bayer in1899 and became a popular analgesic in the United States afterWorld War I. With the market emergence of acetaminophen in theearly 1950s and subsequently other analgesics, the use of aspirinfor postsurgical pain relief dramatically declined, partially becauseaspirin’s undesirable effects on platelets were absent or diminishedwith the newer drugs. However, aspirin has enjoyed a resurgencerecently, being used as a prophylactic clotting inhibitor.

Other drugs have also emerged in the marketplace because theyinduce an aspirinlike platelet inhibition and reduce the risks of un-wanted clotting. With increasing frequency, patients needing surgi-cal procedures are being seen in dental offices and their drug regi-mens include aspirin or other platelet-inhibiting drugs. Dentists

ELEVEN MYTHS OF DENTOALVEOLAR SURGERYROGER E. ALEXANDER, D.D.S.

Through the years, dentists who

perform dentoalveolar surgery

have perpetuated many myths

and other unproven beliefs from

one generation to another.

Sometimes, these beliefs originat-

ed in older textbooks, while oth-

ers were given birth by mentors

sharing anecdotal experiences

with their students. Even today,

many of these scientifically un-

supported statements are perpet-

uated in surgical textbooks and in

continuing education forums and

are passed on to students in den-

tal schools. In today’s evolving en-

vironment of evidence-based

medicine and dentistry, these

anecdotal observations do not

withstand scrutiny. The purpose

of this article is to review the

more common surgical myths and

to test their validity against

scientific evidence.

A B S T R A C T

CLINICAL

PRACTICE

Copyright ©1998-2001 American Dental Association. All rights reserved.

have been warned of dire conse-quences when performingsurgery on such patients, sothey may deny needed treat-ment or expose the patient tounnecessary additional medicalexpenses.

One dental pharmacologytext and at least one oralsurgery text advise discontinu-ing aspirin therapy one week be-fore extensive surgery, withoutproviding any scientific justifica-tion for the recommendation orprecautionary comments on thepotential legal risks and impli-cations of discontinuing medica-tion prescribed by a physicianfor medical purposes withoutconsulting with the physician.3,4

Effects of aspirin andplatelet-inhibiting drugs onhemostasis. After injury,platelets attach to a damagedvessel wall by a release reactionmediated by the binding of vonWillebrand factor to receptorson a monolayer of endothelialcells lining the blood vessels.5

These cells are normally throm-boresistant. Factors in this re-lease reaction include the cy-clooxygenase metabolitesthromboxane A2 in plateletsand prostaglandin I2, as well asprostacyclin and nitric oxide inthe endothelial cells. Platelet-derived thromboxane A2 andendothelium-derived prostacy-clin (and nitric acid) have oppo-site effects, and the balance oftheir production is an importantdeterminant in blood fluidityand hemostasis.5

Individual platelets are sen-sitive to aspirin inactivation ofcyclooxygenase and are affectedfor the duration of their seven-to-10-day circulation lifetime.In contrast, the endothelial cellsrecover rapidly after exposurebecause they can continuouslysynthesize new, unacetylated

cyclooxygenase.6 A single doseof aspirin will inhibit plateletaggregation within two hours ofadministration, and blood sali-cylate levels can persist for fourto seven days, long after the lev-els are clinically undetectable.5

Platelet adhesion functionwill be compromised until a suf-ficient number of affectedplatelets are replaced by new,uninhibited platelets that havenot been exposed to the drug.

Ingestion of alcohol can furtherprolong the bleeding time pro-duced by aspirin and non-steroidal drugs. An AmericanMedical Association pharmacol-ogy reference book notes thatlarge doses of aspirin taken forseveral days can also cause hypoprothrombinemia, but it isusually not clinically significantunless the patient is taking an-other anticoagulant.7

By contrast, nonsteroidalanalgesics, such as ibuprofen,produce a weaker, transient ef-fect that normalizes within 12hours after exposure.5 Long-term use of nonsteroidal anti-inflammatory drugs producesless-predictable changes, how-ever. One study involvingibuprofen demonstrated anatypical, significantly prolongedbleeding time two hours after asingle 600-mg dose was taken.5

The Ivy bleeding time is gen-erally considered the best clini-cal screening test for platelet ac-

tivity. Interestingly, it has beenshown that the effect is dose-de-pendent and longer bleedingtimes, paradoxically, can occurwith lower doses of aspirin.8 Thebleeding time can be prolongedbecause of other factors, howev-er, including technical artifactsin the laboratory. Furthermore,it cannot be extrapolated that aprolonged bleeding time will re-sult in a clinical bleeding prob-lem elsewhere in the body. Forexample, a prolonged skinbleeding time may not be associ-ated with prolonged bleedingfrom an endoscopic stomachbiopsy procedure.9 Bleedingtimes can also be prolongedowing to defects of platelet func-tion other than adhesion.

Aspirin has been implicatedwith clinically significant bleed-ing, but the results have notwithstood the scrutiny of meta-analysis.5 Schafer noted thatthe clinical relevance of onestudy that demonstratedincreased perioperative bloodloss during hip arthroplasty hasbeen questioned, and studies ofpatients receiving aspirin thera-py who underwent cholecystec-tomy and coronary artery by-pass procedures have shownhighly variable results.5

Although cases of spontaneousgastrointestinal hemorrhagehave been reported, the pre-dominant conclusion of the lit-erature, as reviewed by Schafer,is that aspirin-induced exces-sive bleeding is of marginalclinical significance in most pa-tients.5 A search of the litera-ture for the past three decadesfailed to discover a single articlein which clinically significantbleeding after tooth extractionwas directly and primarily at-tributable to a patient’s receiv-ing aspirin or other platelet-in-hibiting drug therapy.

1272 JADA, Vol. 129, September 1998

CLINICAL PRACTICE

Aspirin has beenimplicated withclinically significantbleeding, but theresults have not with-stood the scrutiny ofmeta-analysis.


The bottom line. The long-term use of aspirin and non-steroidal drugs appears rarelyto cause any clinically signifi-cant bleeding problems, even inmajor general surgery cases.There is no evidence in the lit-erature that dental surgerymust be delayed to discontinueaspirin therapy. The decision toperform oral surgery should bemade on a case-by-case basis,with dental professionals bal-ancing the potential risk ofbleeding with the urgency, typeand extent of the planned proce-dure(s). It is unlikely that a pa-tient taking aspirin or otherplatelet-inhibiting drugs willhave a clinically significantbleeding problem after removalof one or two teeth, placementof implants or other minor pro-cedures. With more extensivesurgery, such as full-mouth ex-tractions, extensive deep scal-ing or periodontal surgery, anincreased emphasis on localhemostatic procedures, such asuse of sutures, superficial laserand/or products such as oxi-dized cellulose or absorbablegelatin sponge, may be prudent.

MYTH NO. 2: PATIENTSSHOULD USE SALT-WATER MOUTHRINSESAFTER SURGERY

For more than 50 years, numer-ous textbooks have advocatedthe use of salt water (saline) forsurgical mouthrinses, apparent-ly on the premise that it is themost physiologic irrigant avail-able and will not adversely af-fect healing tissues. Interest-ingly, nearly every textbook hashad a different recipe for whatconstitutes saline, and the guid-ance has ranged from no guide-lines at all to explicit formulasfor mixing ingredients (general-ly 1/4 to 1 teaspoon table saltadded to tap water in amounts

ranging from 8 to 12 fluidounces to a glass or cup). Noneof the guidelines have rested onany type of scientific foundation.They were anecdotal formulaspassed from one doctor to anoth-er, and perpetuated withoutquestion. These unfounded rec-ommendations persist in arti-cles and books today.

A search of the literaturefailed to reveal a single articlethat proves that salt water (as atransient mouthrinse) has anyadvantage over plain tap water

in treating or preventing infec-tion, or in maintaining oral hy-giene. Further, I could find noarticle that proves in a scientifi-cally valid manner that inter-mittent clinical use of regular(tap) water has any adverse ef-fect on healing tissues or in theresolution of infections.

I also could find no evidencethat patients are able to mix aphysiologic saline solution froma recipe provided by a doctor.Almost a decade ago, Whineryquestioned the viability of usingsaline as a mouthwash.10 In atwo-part study, Verser andAlexander studied exactly whichformula of table salt and watermost closely resulted in a physio-logic saline solution.11 They dis-covered that several combina-tions of the two ingredientswould result in near-normalsaline, including 1/4 tsp salt in 6fluid ounces of water, 1/2 tsp saltin 10 oz of water or 3/4 tsp salt in

14 oz of water. Using the secondformula, they then asked volun-teer patients to mix the solutionfrom a written recipe, and foundthat patients could not follow theinstructions. They could not evenselect the proper container size,and wound up with hypotonic orhypertonic solutions, some signif-icantly hypertonic. The authorsrecommended that doctors whoare convinced that warm salinesolutions are superior to warmwater should provide bottledsaline to their patients to heatup.11

The bottom line. There isno evidence that intermittentuse of salt water has any ad-vantage over plain tap water inimmunocompetent patients,and patients have been shownto be incapable of mixing accu-rate solutions from provided in-structions. Warm tap watermouth soaks or rinses should beconsidered therapeuticallyequivalent to homemade salinerinses, until scientific evidencedemonstrates otherwise.

As a matter of prudence, im-munocompromised patientsmight be advised to use bottledsterile solutions of water orsaline because of potential mi-crobial contamination (for ex-ample, Cryptosporidium) incommunity water supplies,until the precise degree of riskcan be determined in futurestudies. Clinicians who believethat patients require salinerinses should provide premixedsolutions.

MYTH NO. 3: DRINKINGTHROUGH A STRAW ORSUCKING WILL DISLODGETHE BLOOD CLOT FROMTHE ALVEOLUS

Through the decades, virtuallyevery doctor’s postsurgical in-struction sheet has carried anadmonition to patients to re-


CLINICAL PRACTICE

There is no evidencethat intermittent useof salt water has anyadvantage over plaintap water in immuno-competent patients.


frain from drinking (or sucking)through a soda straw or suckingon the extraction site, apparent-ly on the premise that the in-traoral vacuum created willdraw the blood clot from thealveolus, causing localized alve-olitis (dry socket), infection orhealing problems. Again, asearch of the scientific litera-ture from the past 30 yearsfailed to discover a single articlethat provides statistically validevidence that this premise hasmerit. Likewise, the literatureis devoid of any studies thatdocument clinically significantpostsurgical dental problemsthat could be scientifically at-tributed to such activities.

When a tooth is removed, asequence of inflammation, ep-ithelialization, fibroplasia andremodeling is initiated.12,13

Within the first day, the fibrin-covered clot is held in positionby gingival tissue. Unsupportedgingival tissues collapse intothe clot-filled alveolus, whichhelps keep the clot in position.Within 48 hours, there is an in-growth of fibroblasts and capil-laries, and epithelium migratesdown the socket wall until itcontacts epithelium or granula-tion tissue. By the third day,fibroblasts have proliferatedand grown into the peripheralportions of the clot.

Therefore, the blood clot ismechanically secured withinthe first 24 to 48 hours aftertooth removal, and the securityof the clot increases over thenext 48 hours. It is logical to be-lieve that the clot has some in-ternal resistance to any me-chanical dislodgement bylow-suction vacuum or suckingon a straw, even within the firstfew hours after surgery. Itseems unlikely that a patient-induced oral vacuum would be

instrumental in causing a viableclot to be dislodged from an ex-traction site, but reliable scien-tific data are lacking to conclu-sively prove or disprove thisrationalization. Furthermore,this alleged problem should notbe confused with the pathophys-iology of localized alveolitis (drysocket), which generally occursthree to five days (or more) aftersurgery and involves fibrinolytic(not mechanical) activities with-in the clot.14

The bottom line. I couldfind no scientific evidence thatsucking through a soda strawhas any relationship to postsur-gical sequelae, and when onelogically considers the process ofintra-alveolar extraction-sitehealing, such events seem im-probable. However, a valid, dou-ble-blinded study of this topicwould be beneficial.

MYTH NO. 4: DRINKINGCARBONATED BEVER-AGES WILL CAUSE DRYSOCKETS OR OTHERPROBLEMS

For several decades, many dentalprofessionals have believed thatdrinking carbonated beverageswill bubble the blood clot out ofan alveolus. As noted in the dis-cussion of drinking through sodastraws, this belief also has no ap-parent scientific foundation. Myreview of the literature failed toyield a single study that docu-ments increased morbidity after

oral surgery when patients drinkcarbonated beverages. Perhapsthe belief arose from use of hy-drogen peroxide as a mouth-wash, which results in the re-lease of oxygen and creates abubbling action. A prospective,double-blinded clinical study thatcompares the postsurgical use ofcarbonated beverages withnonuse would be a welcome addi-tion to the literature.

The bottom line. I couldfind no published clinical datathat prove a relationship be-tween drinking carbonated,nonalcoholic beverages andpostsurgical morbidity orwound healing problems. Untilsuch evidence is presented, thebelief appears to be a mythbased on anecdotal clinical advi-sories.

MYTH NO. 5: DRINKINGALCOHOL-CONTAININGBEVERAGES WILL CAUSEDRY SOCKETS

This common admonishment topatients appears to be groundedmore in pharmacology than inclinical sequelae. Alling and as-sociates15 pointed out that alco-hol is a direct platelet toxinand, therefore, will affect bleed-ing. However, I could find no ev-idence in the literature thatonce a blood clot has formed, oc-casional alcohol use can causehemorrhage to recur. In fact,many clinicians instruct theirpatients to use chlorhexidine-based mouthrinses beforeand/or after surgery, and theseproducts contain 11.6 percentalcohol. By comparison, mostwines contain 8 to 14 percentalcohol, and most light beerscontain only 2.5 percent alcohol.

Alcohol has many deleteriouseffects on virtually every bodytissue, especially when con-sumed daily.16 Bleeding prob-lems can arise secondary to


CLINICAL PRACTICE

It seems unlikely thata patient-induced oralvacuum would be in-strumental in causinga viable clot to bedislodged from an ex-traction site.


liver damage from long-term,preoperative alcohol use, as aresult of impaired synthesis ofseveral coagulation factors.Ethyl alcohol is also a directbone marrow depressant, solong-term use can lead tothrombocytopenia and defectivered and white blood cells.Alcohol can prolong the bleed-ing time through its interac-tions with platelets that havebeen compromised by aspirinand nonsteroidal drug use.Excessive, long-term alcohol usecan interfere with healing, com-promise inflammatory respons-es such as leukocyte migration,and damage cells, but the liter-ature does not provide evidencethat an occasional alcoholic bev-erage can dissolve establishedintra-alveolar blood clots.

The bottom line. Dentistsshould counsel all patients torefrain from drinking alcoholicbeverages after surgery, butnot to prevent dry sockets orloss of the blood clot. Such ad-vice should be based on the ad-verse effects of alcohol on heal-ing and the potential forinteractions with medicationsthat are likely to be prescribedduring the immediate postoper-ative period.

MYTH NO. 6: MENSTRU-ATING WOMEN WHO UN-DERGO SURGERY WILLHAVE SIGNIFICANT POST-OPERATIVE BLEEDING

Although this myth seems final-ly to be falling into oblivion, fordecades clinicians have believedthat women should wait untilmenstrual bleeding has finishedbefore undergoing dentalsurgery because they were atrisk of postoperative hemor-rhaging. There is only a touchof scientific reality behind thismyth, and very little clinical impact.

There is little agreement inthe literature on how long apatient should be expected tohemorrhage after an extrac-tion, with estimates rangingfrom 30 minutes to 24 hours.Presumably, prolonged bleed-ing exceeds one hour and canlast up to 24 hours, makingcomparisons difficult and de-terminations of normal subjec-tive.

I could find no publishedstudies that demonstrated clini-cally significant prolongedbleeding in women who undergooral surgical procedures duringtheir menstrual periods.

Estrogens can result in greaterclinical bleeding of cut surfaces,but it is not clinically signifi-cant or a contraindication forsurgery.17

The bottom line. There isno scientific evidence that fe-male patients will experienceany significantly prolongedhemorrhaging after dentoalveo-lar surgical procedures, regard-less of whether they are havingtheir menstrual period.

MYTH NO. 7: PATIENTSSHOULD NEVER RECEIVEBILATERAL THIRD-DIVI-SION (MANDIBULAR)ANESTHETIC BLOCKS

I have observed a perplexing be-

lief among some practicing den-tists that patients should notreceive bilateral third-division(inferior alveolar) nerve blocks.Some faculty members in excel-lent dental schools even presentthe philosophy to dental stu-dents. It is hard to imaginewhere this myth arose, since itis not found in any contempo-rary textbook on dental localanesthesia. It might be an un-conscious extension to adults ofthe conventional wisdom toavoid bilateral mandibularnerve anesthetic blocks inyoung children whenever possi-ble, to minimize the risk of thechild’s chewing on the lower lipwhile anesthetized.

However, any surgeon whoremoves four third molars atone appointment routinely ad-ministers bilateral local anes-thetic blocks, so the precau-tionary pediatric principle doesnot extend logically to adults.The myth might also havebeen perpetuated under thepremise that bilateral blockscould somehow create a poten-tial airway problem for pa-tients. This belief also is notrational or based in science.My review of the literature didnot reveal a single case of anolder child’s or adult’s experi-encing a significant complica-tion that was attributable tobilateral mandibular anesthe-sia alone.

The bottom line. Admin-istration of local anestheticshould be dictated by the needsof the patient and the proce-dures planned, with full knowl-edge of all known risks.Bilateral mandibular anestheticblocks are appropriate proce-dures, especially in adult pa-tients, whenever the treatmentplan and doctor’s judgment dic-tate a need for them.


CLINICAL PRACTICE

A review of theliterature did notreveal a single caseof an older child’s oradult’s experiencing a significant compli-cation that wasattributable tobilateral mandibularanesthesia alone.


MYTH NO. 8: ORAL POST-OPERATIVE INSTRUC-TIONS ARE SUFFICIENT

Patients who receive both writ-ten and oral instructions aftersurgery experience less postop-erative morbidity, have lesspain and are more compliant.18,19

Patients who receive only oralinstructions do not rememberthem.20 It is medicolegally andclinically prudent to providesuch instructions in writing,but many dentists do not go tothe trouble of preparing writteninstructions. They counsel pa-tients orally after surgery, orperhaps use a generic, commer-cially produced informationsheet, which may or may not becorrect and/or useful. Even ifwritten information is provided,professionals rarely determineif the instructions can be under-stood by patients with limitedliteracy and comprehensionabilities.

Adequate postoperative coun-seling has been shown to mini-mize complications and havepositive clinical results. In astudy by Vallerand and associ-ates,18 postoperative pain con-trol and satisfaction were foundto be greater in patients who re-ceived extensive writtenpreparatory information.

There is growing concernamong health care professionalsabout the inability of a signifi-cant portion of the U.S. popula-tion to read and function in ourhealth care system.21 Studieshave estimated that as many as20 to 48 percent of adults do nothave the literacy skills neces-sary to function in modern soci-ety.21,22 Patients’ abilities tofunction well socially oftenmask their inability to under-stand instructions from healthcare professionals, and vocabu-lary is a particular problem

area.20 Many patients will notadmit that they do not under-stand common terms such asthree-fourths, hemorrhage, con-sume, discard, teaspoon or re-frain. This has significant im-plications regarding theirabilities to follow directions,comply with medication direc-tives, and read and understandpostoperative instruction sheetsafter oral surgery, if such sheetsare provided.

In one small, unpublishedclinical research project,patients, all of whom werehigh-school graduates, could re-member only 67 to 83 percent of

the significant information pro-vided to them orally, whenquestioned less than one hourafter oral surgery via a ques-tionnaire (R. Alexander, unpub-lished data, 1989). It is logicalto assume that in many less-ed-ucated patients, the oral reten-tion rate could be significantlyworse. Without written rein-forcement, the understandingand retention of oral instruc-tions over a lengthy recoveryperiod cannot be ensured, evenamong literate patients.

The bottom line. Althoughno published studies have ex-amined the importance of writ-ten reinforcement of oral post-operative instructions indentistry, nor examined howwell they are understood by pa-tients, the preponderance of

medical literature suggests it isimportant that written instruc-tions be provided, coupled withoral reinforcement. Written in-structions should contain shortsentences, drawings, brief para-graphs and words with few syl-lables. Unfamiliar medical jar-gon should be avoided.20,22,23

MYTH NO. 9: TEETHSHOULD NEVER BEEXTRACTED IN THEPRESENCE OF ACTIVEINFECTION

The primary goals of infectionmanagement are to drain pusand necrotic debris and to re-move the cause of the infection.Often, these goals can be accom-plished most expeditiously byremoving the offending tooth orteeth as soon as possible, if alloptions for salvage have beeneliminated. This often requiresestablishment of an antibioticblood level before the extractionis carried out. It is no longernecessary to wait for resolutionof the infection, however.Although the philosophy ofwaiting to extract a tooth ap-pears to be a carryover from thepreantibiotic era of infectionmanagement, Hall and associ-ates24 long ago reminded us thatearly removal actually existedbefore antibiotic use becamewidespread.

In 1951, Krogh25 studied3,000 patients and showed thatteeth could be safely extractedin the presence of acute infec-tion, which probably resulted infaster resolution of the infectionand rarely caused complica-tions. In the majority of Krogh’scases, antibiotics were not usedbefore surgery. These findingswere reproduced in three laterstudies involving 350, 720 and1,376 patients.26-28 Martis andKarakasis26 concluded that “im-mediate extraction results in a


CLINICAL PRACTICE

Patients’ abilities tofunction well sociallyoften mask theirinability to under-stand instructionsfrom health careprofessionals.


faster resolution of the infectionand that it is a safe procedurewithout serious complications.”Rud28 pointed out that the argu-ments against immediate ex-traction generally arise out ofconcern over potential litigationand anecdotal experiences in-volving a case or two in whichserious complications did occur.Such complications might haveoccurred even if the extractionhad been deferred, and shouldnot provide a foundation for ac-ceptable management practices.

This philosophy of early ex-traction does not imply a cava-lier approach to surgery in aninfected patient, however. Therisks of anesthetic injection andtooth extraction must always beweighed against the anticipatedbenefits of early removal, andthe clinician must take into con-sideration the systemic medicalcondition of the patient, the an-ticipated degree of patient com-pliance with the drug regimen,surgical access to the tooth andthe clinician’s skill and experi-ence. Difficult or potentiallytraumatic surgical extractionsmight be better managed byspecialists who have extensiveexperience in such cases.

The bottom line. In thisera of antibiotic availability, itis possible to combine medicaland surgical treatment to bringabout a rapid resolution ofmost odontogenic infections.That is not to say that clini-cians should be casual aboutextracting teeth in the pres-ence of an acute infection, but,rather, that extraction neednot be deferred in healthy pa-tients until the acute infectionhas completely resolved.Indeed, deferral might resultin a worsening of the infection,if pus is not evacuated throughan incision for drainage.

Patients who are severely in-fected, are immunologicallycompromised or suppressed, orhave uncontrolled metabolicdiseases should begin an appro-priate antibiotic regimen andimmediately be referred to anexperienced surgeon. This isalso true if the anticipated pro-cedure is potentially traumaticor otherwise difficult.

MYTH NO. 10: DENTISTSSHOULD NOT PERFORMSURGERY ON A PREG-NANT PATIENT IN THEFIRST OR THIRDTRIMESTER

Many dentists are extremely re-luctant to perform dentoalveo-lar surgery on a pregnantwoman at any time, but espe-cially during the first and thirdtrimesters, even when the pa-tient has acute, severe symp-toms and no other treatment al-

ternatives exist. A variety ofreasons have been expressed forthis reluctance, including thefear of litigation if the fetus suf-fers any birth defect; the fear ofspontaneous delivery in the of-fice; concerns about radiation,anesthesia and patient manage-ment; and postoperative medi-cation concerns. These concernshave no more clinical signifi-

cance than they would for anypatient receiving treatment.

Ideally, elective surgeryshould be confined to the mid-dle trimester, because that isusually the patient’s most sta-ble time. Emergency surgery forthe relief of infection, pain orsuffering can be performed atany time during pregnancy,however, provided appropriateprecautions and risk manage-ment steps are followed. Theseinclude the following:dexposure to radiation for es-sential films only (with propershielding);dadequate and documentedpatient counseling and in-formed consent;dobstetric consultation whenand where indicated;dmedical consultation whenindicated for possible anemia(about 20 percent of pregnan-cies)30;duse of appropriate medica-tions intraoperatively and post-operatively.

Concerns about potentialfetal damage are markedly re-duced after the first trimester.Guyton and Hall17 pointed outthat the highest risk period offetal development is largelycompleted by the fifth month,and the details of all majororgan systems have been“blocked out.” During the nextfour months, cellular refine-ments occur in each organ sys-tem. After the 12th week, therisks of fetal compromise do notchange dramatically, althoughdevelopment is not fully fin-ished until the final month.Statistically, the risks are lowbut necessary when balancedagainst a needed procedure torelieve acute pain or infection.Also, I found no statistically sig-nificant incidence of sponta-neous abortions or miscarriages


CLINICAL PRACTICE

The argumentsagainst immediateextraction generallyarise out of concernover potential litiga-tion and anecdotalexperiences involvinga case or two inwhich serious compli-cations did occur.


associated with dental treat-ment in the literature over thepast 30 years.

Clinically, I occasionally hearthe belief expressed that preg-nant women will have pro-longed bleeding after surgery.In fact, pregnancy is considereda state of hypercoagulability,with increased platelet aggrega-tion, increases in coagulationfactors and decreased fibrinoly-sis.17 This would logically de-crease the possibility of unto-ward bleeding after anextraction.

Concerns over dental chairdelivery in the third trimesteralso appear to be theoretical.My review of the literature inthe past 30 years revealed nocase reports of serendipitousdental office deliveries. Even ifa patient goes into labor, thewidespread availability of emer-gency medical services meansthat assistance would be provid-ed very quickly.

A more realistic concern inthe final trimester is pregnancyhypotension, induced by thefetus pressing on the vena cavawhen the patient is in a pro-longed supine or semirecliningposition, thus reducing the re-turn of blood flow to the heart.This can be alleviated by turn-ing the patient slightly to theleft, which takes the weight ofthe fetus off the liver and venacava. Aspirin and nonsteroidalanalgesics should be avoided inthe last trimester. About 10 to20 percent of all pregnantwomen are mildly anemic, butthis would not place them atany risk during a minor surgi-cal procedure.29,30

The bottom line. Althoughelective procedures are per-formed with the least risk dur-ing the middle trimester, thereis no valid reason for deferring

or withholding essential, emer-gency surgery from a patientwho has an uncomplicated preg-nancy, solely because of con-cerns for the fetus or the moth-er. Dentists should consult withthe patient’s obstetrician orother physician whenever man-agement questions exist, and itis incumbent on every dentist tounderstand the risks related tosurgical management. This in-formation is readily available innumerous dental textbooks.29

MYTH NO. 11: PATIENTSSHOULD NOT EAT ORDRINK ANYTHING AFTERMIDNIGHT BEFORE RE-CEIVING INHALATION ORINTRAVENOUS SEDATION

For decades, patients who havebeen scheduled to undergo in-halation or receive oral or intra-venous conscious sedation orgeneral anesthetic have beenadmonished to eat or drinknothing after midnight the nightbefore the procedure. Over theyears, this directive has been re-

laxed somewhat, and doctorsnow typically counsel their pa-tients to eat or drink nothing forfive to six hours before dentalprocedures. Data in the lastthree to five years suggest thateven these relaxed advisoriesare of doubtful scientific validi-ty, and the American Society ofAnesthesiology reportedly is onthe verge of releasing newguidelines that will further

modify these recommendations.In the past decade, studies

have been published that refutethe need for prolonged preoper-ative fasting in patients to pre-vent aspiration; this includespatients undergoing inhalationand intravenous conscious seda-tion procedures. In a 1993study, Warner and colleagues30

found only 67 cases of aspira-tion out of more than 215,000cases involving general anes-thetics, and 15 of the 67 wereemergency cases involving pa-tients who were known to havefull stomachs.

As early as 1833, researchersshowed that fluids pass throughthe stomach fairly quickly andsolid foods require three to fivehours to empty (Roger Maltby,M.D., oral communication,American Association of Oraland Maxillofacial SurgeonsAnnual Meeting, Seattle, Sept.21, 1997). Since about 1970,however, the empiric “nothingby mouth” past midnight direc-tive has been with us in oneform or another.

Several physiology studiessince the 1970s showed thatsolid foods are normally emp-tied from the gut within fourhours and 99 percent of water isgone after two hours.31,32 Studieshave also shown that patientswho drink fluids before surgeryhave smaller residual gastricvolumes at surgery than pa-tients who drink no fluids foreight to 12 hours beforesurgery. Researchers haveshown that even in cases of ob-served aspiration, patients whodo not develop symptoms withintwo hours rarely have respirato-ry sequelae.29 American anes-thesiologists are consideringnew guidelines that allow inges-tion of clear liquids (water,pulpless fruit juice, plain tea or


CLINICAL PRACTICE

In the past decade,studies have beenpublished that refutethe need for pro-longed preoperativefasting in patients toprevent aspiration.


coffee, or soda pop) up to twohours before surgery and solidfoods or dairy products up tofive hours before surgery.

Numerous studies within thepast decade have shown thatthe routine use of antacids, acidblockers, gastrointestinal stim-ulants or antiemetics are of nobenefit before conscious seda-tion or general anesthetic is ad-ministered (Roger Maltby,M.D., oral communication,AAOMS Annual Meeting,Seattle, Sept. 21, 1997).

The bottom line. Prolongedfasting and restriction of fluidintake have been proven to be ofno value and of some possibleharm in patients about to re-ceive conscious sedation or gen-eral anesthetic. Clear fluids needbe restricted for only two tothree hours, and solid foods forfour to five hours before admin-istration of any conscious seda-tion. Even when a general anes-thetic is to be administered, therisk of aspiration is extremelysmall to nonexistent with theseguidelines in place.

CONCLUSIONS

J. Chalmers Da Costa (1863 to1933) once said, “A man whohas a theory which he tries to fitto facts is like a drunkard whotries his key haphazardly indoor after door, hoping to findone it fits.” Many oft-cited be-liefs, including those reviewedabove, are seemingly innocent.They have, however, been per-petuated for decades in our liter-ature, our schools and our con-tinuing education courses asfacts, despite the lack of valid,scientific, statistically verifiable

and unbiased data to supportthem. In this evolving era of evi-dence-based practice, it is timefor these surgical myths to besubjected to unbiased scientificscrutiny. Until then, they shouldbe set aside as anecdotal fiction,and not be perpetuated as scien-tific gospel. ■

1. Evidence-based Medicine Working Group.Evidence-based medicine: a new approach toteaching the practice of medicine. JAMA1992;268:2420-5.

2. Sackett DL, Rosenberg WM, Gray JAM,Haynes RB, Richardson WS. Evidence basedmedicine: what it is and what it isn’t. BMJ1996;312:71-2.

3. Holroyd SV, Wynn RL, Requa-Clark B.Clinical pharmacology in dental practice. 4thed. St. Louis: Mosby–Year Book; 1988:135.

4. Kwon PH, Laskin DM. Clinician’s manu-al of oral and maxillofacial surgery. Chicago:Quintessence; 1991:114.

5. Schafer AI. Effects of nonsteroidal antiin-flammatory drugs on platelet function andsystemic hemostasis. J Clin Pharmacol1995;35:209-19.

6. Jaffe EA, Weksler BB. Recovery of en-dothelial cell prostacyclin production after in-hibition by low doses of aspirin. J Clin Invest1979;63:532-5.

7. Division of Drugs and Toxicology,American Medical Association. Drug evalua-tion annual 1995. Chicago: American MedicalAssociation; 1995:788.

8. O’Grady J, Moncada S. Aspirin: a para-doxical effect on bleeding-time (letter). Lancet1978;2:780.

9. O’Laughlin JC, Hoftiezer JW, MahoneyJP, Ivey KJ. Does aspirin prolong bleedingfrom gastric biopsies in man? GastrointestEndosc 1981;27:1-5.

10. Whinery JG. Destroying some old myths(letter). J Oral Maxillofac Surg 1988;46:94.

11. Verser SJ, Alexander RE. Use of salineas a postsurgical rinse (letter). Oral Surg OralMed Oral Pathol 1994;77:438-9.

12. Hupp JR. Wound repair. In: PetersonLJ, Ellis E, Hupp JR, Tucker MR.Contemporary oral and maxillofacial surgery.2nd ed. St. Louis: Mosby–Year Book; 1993:66.

13. Shafer WE, Hine MK, Levy BM.Textbook of oral pathology. 4th ed.Philadelphia: Saunders; 1983:602.

14. Swanson AE. Prevention of dry socket:an overview. Oral Surg Oral Med Oral Pathol1990;70:131-6.

15. Alling CC, Helfrick JF, Alling RD.Impacted teeth. Philadelphia: Saunders;1993:83.

16. Leonard RH. Alcohol, alcoholism, anddental treatment. Compend Contin EducDent 1991;12:274-83.

17. Guyton AC, Hall JE. Textbook of medi-cal physiology. 9th ed. Philadelphia:

Saunders; 1996:1024-47.

18. Vallerand WP,Vallerand AH, HeftM. The effects ofpostoperativepreparatory informa-tion on the clinicalcourse following thirdmolar extraction. JOral Maxillofac Surg1994;52:1165-70.

19. Culbertson VL,Arthur TG, RhodesPJ, et al. Consumerpreferences for verbaland written medica-tion information.Drug Intell ClinPharmacol1988;22:390-6.

20. Weiner MF,Lovitt R. An examina-tion of patients’ un-derstanding of infor-mation from health

care providers. Hosp Community Psych1984;35:619-20.

21. Miles S, Davis T. Patients who can’tread: implications for the health care system.JAMA 1995;274:1719-20.

22. Levoy B. Communicating with low-liter-acy patients. Dent Economics 1995;85:14.

23. Baker GC, Newton DE, BergstresserPR. Increased readability improves the com-prehension of written information for patientswith skin disease. J Am Acad Dermatol1988;19:1135-41.

24. Hall HD, Gunter JW, Jamison HC,McCallum CA. Effect of time of extraction onresolution of odontogenic cellulitis. JADA1968;77:626-31.

25. Krogh HW. Extraction of teeth in thepresence of acute infections. J Oral Surg1951;9:136-51.

26. Martis CS, Karakasis DT. Extractionsin the presence of acute infections. J Dent Res1975;54:59-61.

27. Martis C, Karabouta I, Lazaridis N.Extractions of impacted mandibular wisdomteeth in the presence of acute infection. Int JOral Surg 1978;7:541-8.

28. Rud J. Removal of impacted lower thirdmolars with acute pericoronitis and necrotis-ing gingivitis. Br J Oral Surg 1970;7:153-60.

29. Little JW, Falace DA, Miller CS, RhodusNL. Dental management of the medicallycompromised patient. 5th ed. St. Louis:Mosby–Year Book; 1997:434-5.

30. Warner MA, Warner EW, Weber JG.Clinical significance of pulmonary aspirationduring the perioperative period.Anesthesiology 1993;78:56-62.

31. Hinder RA, Kelly KA. Canine gastricemptying of solids and liquids. Am J Physiol1977;233:E335-40.

32. Miller M, Wisehart HY, Nimmo WS.Gastric contents at induction of anesthesia: isa 4-hour fast necessary? Br J Anaesth1983;55:1185-8.


CLINICAL PRACTICE

Dr. Alexander is an

associate professor

of oral and maxillofa-

cial surgery,

Department of Oral

and Maxillofacial

Surgery and

Pharmacology,

Baylor College of

Dentistry–TAMUS,

P.O. Box 660677,

Dallas, Texas 75266-

0677. Address

reprint requests to

Dr. Alexander.


11 myths of dentoalveolar surgery

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