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http://jdr.sagepub.com/content/91/7_suppl/S72The online version of this article can be found at:

DOI: 10.1177/0022034512447949

2012 91: S72J DENT RES

M. Ferrari, A. Vichi, G.M. Fadda, M.C. Cagidiaco, F.R. Tay, L. Breschi, A. Polimeni and C. GoracciA Randomized Controlled Trial of Endodontically Treated and Restored Premolars

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JDR Clinical Research Supplement July 2012

DOI: 10.1177/0022034512447949. 1Department of Dental Materials and Fixed Prosthodontics of the University of Siena, Tuscan School of Dental Medicine, University of

Firenze and Siena, Policlinico Le Scotte, viale Bracci, Siena 53100, Italy;2Department of Endodontics, College of Dentistry, Georgia Health Sciences University, 1120 15th

Street, Augusta, GA, USA; 3Department of Medical Sciences, University of Trieste, Piazza, Ospedale 1, Trieste 34129, Italy; and 4Department of Oral Sciences, Sapienza

University of Rome, v iale Regina Elena 287/A, Roma, Italy; *corresponding author, [email protected]

International & American Associations for Dental Research

M. Ferrari1*, A. Vichi1, G.M. Fadda1, M.C. Cagidiaco1, F.R. Tay2, L. Breschi3,A. Polimeni4, and C. Goracci1

A Randomized Controlled Trialof Endodontically Treated andRestored Premolars

CLINICAL TRIALS

Abstract: Thisin vivo study examinedthe contribution o remaining coro-

nal dentin and placement o a preabri-

cated (LP) or customized fber post (ES)

to the six-year survival o endodonti-

cally treated premolars. A sample o 345

patients provided 6 groups o 60 premo-

lars each in need o endodontic treat-

ment. Groups were classifed accord-

ing to the number o remaining coronal

walls beore abutment build-up. Within

each group, teeth were allocated to one

o three subgroups: (A) no post reten-tion; (B) LP; or (C) ES (N = 20). All

teeth were protected with a crown. Cox

regression analysis revealed that fber

post retention signifcantly improved

tooth survival (p < 0.001). Failure risk

was lower in teeth restored with preab-

ricated (p = 0.001) than with custom-

ized posts (p = 0.009). Teeth with one

(p = 0.004), two (p < 0.001), and three

coronal walls (p < 0.001) had signi-

icantly lower ailure risks than those

without errule. Similar ailure risks

existed or teeth without coronal walls,regardless o the presence/absence o

errule (p = 0.151). Regardless o the

restorative procedure, the preservation

o at least one coronal wall signifcantly

reduced ailure risk (ClinicalTrials.govnumber CT01532947).

Key Words: ber posts, clinical trial,luting, restorations, errule, ailure risk.

Introduction

Fiber posts have been used clinicallyas an alternative to metal posts in therestoration o endodontically treated

teeth (Ferrari et al., 2000a,b, 2007b;Cagidiaco et al., 2008b; Goracci andFerrari, 2011). Although in vitro testsprovide valuable inormation to predictthe clinical outcome o restorativematerials and techniques, clinical trialsindisputably generate the most reliableevidence. The clinical literature on theuse o ber posts includes retrospective(Fredriksson et al., 1998; Ferrari et al.,2000a, b, 2007a) and prospective studies(Glazer, 2000; Mannocci et al., 2002;Malerrari et al., 2003; Monticelli et al.,

2003; Naumann et al., 2005a,b; Ferrariet al., 2007b; Cagidiaco et al., 2008a;Mancebo et al., 2010; Zicari et al., 2011).

Dierent ailure rates have beenreported or post-endodontic restorations

(Naumann et al., 2005a; Ferrari et al.,2007a,b; Mancebo et al.,2010; Zicariet al.,2011). Among the baseline actorsinfuencing the clinical outcome orestored pulpless teeth, tooth typeand position within the dental arch inrelation to occlusal orces (Naumannet al., 2005a,b), existence o proximalcontacts (Caplan et al., 2002), and thetype o nal restoration (Aquilino andCaplan, 2002) have been identiedto play a relevant role. Moreover,

preservation o coronal dental tissues(the so-called errule eect, acircumerential dentin collar o at least2 mm in height) has emerged as thecritical condition or unctioning o post-endodontic restorations (Stankiewiczand Wilson, 2002; Zhi-Yue and Yu-Xing,2003; Akkayan, 2004; Tan et al., 2005;Pereira et al., 2006; Dietschi et al., 2008;Mancebo et al. 2010; Juloski et al., 2011).

In a Cochrane systematic review onpost-retained restorations, the authorsadvised that clinical protocols should

eature well-dened inclusion criteria,including delineation o the numbero residual coronal walls, or a clearerassessment o the infuence o theremaining tooth structure on treatment


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JDR Clinical Research Supplementvol. 91 suppl no. 1

outcomes (Bolla et al., 2007). Also,observation times longer than three yearsare required (Bolla et al., 2007). Thenecessity or the collection o longer-term data was also stated in a recentlypublished three-year controlled study that

compared the outcome o endodonticallytreated teeth restored with glass berposts and composite cores with thato teeth restored with gold-alloy-basedposts and cores (Zicari et al., 2011).In 2008, Cagidiaco et al. published thendings o a three-year prospectiveclinical trial assessing the outcome oroot-lled premolars with dierentdegrees o coronal tissue loss (Cagidiacoet al., 2008a). The teeth were restoredwithout any radicular retention, or withpreabricated or customized posts. Over

the three-year observation period, postplacement contributed signicantly toreduced ailure risk in restored pulplesspremolars, with preabricated postshaving ewer ailures than customizedposts. The amount o residual coronaldentin also signicantly infuenced theclinical outcome. Regardless o therestorative procedure, preservation oat least one coronal wall was oundto signicantly increase survivalprobability. Similar ailure risks were

identied in teeth with no coronal walls,regardless o the presence or absenceo a errule. The nding o the minimalcontribution o a errule to clinicaloutcomes, and the awareness that longerobservation periods deliver strongerevidence prompted the collection olonger-term data. Thus, the currentprospective clinical trial was developedby recalling the enrolled patients sixyears ater the restorations had beenperormed. Patients were subjected toclinical and radiographic evaluation, to

test the null hypothesis that both theamount o residual coronal dentin andthe placement o a preabricated orcustomized ber post have no eect onthe six-year survival o endodonticallytreated and crowned premolars.

Materials & Methods

A total o 345 patients who consecutivelypresented at a private dental oce or

receiving endodontic treatment andrestoration o premolars provided 6groups o 60 teeth each. No more than 2

teethperpatient were considered or thestudy. The inclusion criteria or selectiono the baseline sample o 360 premolarsin need o root canal treatment have beenindicated in the previously publishedinterim report (Cagidiaco et al., 2008a).The rights o the enrolled participantshave been protected by the InstitutionalReview Board o the University o Siena,Italy, and written inormed consent wasprovided by all participants.

Groups were dened based on theamount o dentin let at the coronallevel ater root canal treatment and

beore abutment preparation (Table 1).Within each group, teeth were randomlysubdivided into three subgroups(N = 20) that were dened based onthe restorative procedure, involvingplacement o a customized (ES) orpreabricated (LP) post or omission othis step (no post) (Table 1).

For all teeth, nal restoration was asingle-unit metal-ceramic crown. Allrestorative procedures were perormed

Group: Amount of Residual Coronal Dentin

Subgroup: Endocanalar

Retention

All coronal walls present No post

Preabricated post*

Customized post

Three coronal walls retained No post

Preabricated post*

Customized post

Two coronal walls preserved No post

Preabricated post*

Customized post

One coronal wall intact No post

Preabricated post*

Customized post

Presence of a ferrule: no coronal wall retained, a collar

of dentin at least 2 mm in height, as measured witha periodontal probe, preserved circumferentially

No post

Preabricated post*Customized post

Absence of a ferrule: no coronal wall retained, less

than 2 mm of dentin present circumferentially

No post

Preabricated post*

Customized post

Failures

Post debonding

Post fracture

Vertical or horizontal root fracture

Failure of the core portion requiring a new coronal

restoration

Displacement of the crown

Endodontic and periradicular conditions requiring

root canal re-treatment

Table 1.

Group Assignment Determined by the Amount o Residual Coronal Dentin

Allocation to subgroups within each group was randomized. Failure events were noted at ollow-up visits.

*DT Light Posts, RTD, St. Egrve, France.EverStick fbers, Stick Tech Ltd., Turku, Finland.


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by the same operator between Januaryand June 2003.

Clinical Procedures

Materials and procedures or root canaltreatment, placement o the intraradicular

retention, and abutment build-up werereported in detail in the three-yearclinical trial (Cagidiaco et al., 2008a).

Evaluation Parameters

Patients were recalled ater 1, 6, 12,24, 36, and 72 mos or clinical andradiographic examination. Loss toollow-up was dened as those whoailed to attend the latest study visit.Periapical radiographs were taken witha modied parallel technique and Ultra-Speed lms (Eastman Kodak Company,

Rochester, NY, USA), and examined at 5 magnication. Two examiners otherthan the operator who had perormedthe restorative procedures independentlyevaluated the patients and recorded theoccurrence o the events listed in Table 1.These occurrences were then categorizedas relative or absolute ailures. Rootractures leading to tooth extractionwere considered as absolute ailures.Success was dened as the outcomein the absence o absolute and relative

ailures, while survival was dened as theoutcome in the absence o absoluteailures (Zicari et al.,2011). The twoexaminers were well-trained in theevaluation o clinical and radiographicsigns, having participated in previousclinical studies o ber post restorations(Ferrari et al., 2000b, 2007a; Monticelliet al., 2003), and no instance odisagreement occurred between thetwo examiners. Examiners could not beblinded as to the type o restoration,since the presence/absence o an

endocanalar retention could readily berecognized in the radiograph.

Statistical Analysis

For descriptive purposes, Kaplan-Meierplots were constructed or subgroups andor subgroup within each group (Fig.).We applied the Cox regression analysis toassess the infuence o type o restoration(no post/LP/ES), amount o residualcoronal dentin, and the interaction

between these two variables on ailurerate. The level o statistical signicancewas set at p < 0.05. Statistical calculationswere handled by the SPSS sotware (SPSSInc., Chicago, IL, USA).

Results

Table 2 presents the patients recallrates at the six-year ollow-up visits.Table 3 shows ailure mode distribution,recall, success, and survival rates atersix years o observation. The loss toollow-up at the six-year recall was 11.9%or patients, 12.3% or restorations. Allthe lost patients could not be reachedby phone or e-mail or the six-yearollow-up visit and were consideredas censored in the Cox regression

analysis. Sixty percent (success rate)o the ollowed-up premolars wereailure-ree ater 72 mos o unction. Interms o the survival rate, 94.1% o theexamined restored teeth were still inclinical service ater six years. The leastsatisactory clinical perormance wasdemonstrated by teeth restored withoutany intraradicular retention (Subgroup A:success rate 42.1%, survival rate 85.9%).Teeth restored with LP (Subgroup B)had higher success and survival rates

than teeth restored with ES (SubgroupC). In the presence o a preabricatedpost, no crown dislodgement was noted,and the occurrence o root racturewas limited to only one case, while themajority o ailure events (12) consistedo post debonding. The latter was mostrequently seen in teeth with a reducedamount o residual coronal dentin(Groups 4-6).

The largest numbers o root racturesand crown dislodgements were reportedin the subgroup o teeth restored without

any intraradicular retention. In thesubgroup o restorations retained withES, a relatively high requency o post/core ractures was observed. Failure oroot canal treatment was noted in 15,7, and 11 cases or Subgroups A, B,and C, respectively. All the endodonticailures presented as asymptomatic apicalperiodontitis. The majority o crowndislodgements and all the root racturesoccurred in teeth in which the remaining

coronal tooth structure beore abutmentbuild-up was reduced to one or twowalls. All the teeth retaining 4 walls(Group 1) were ailure-ree, regardlesso the restorative procedure (i.e., with orwithout intraradicular retention). Group

1 teeth were thus excluded rom thesurvival analysis.Cox regression analysis indicated that

root canal retention was a signicantactor or survival (p < 0.001). Decreasein ailure risk was higher in teeth restoredwith preabricated posts (hazard ratio, HR= 0.3; 95% condence intervals, CI, orHR = 0.1 to 0.6; p = 0.001) than in thoserestored with customized posts (HR =0.4; 95% CI or HR, 0.2 to 0.8; p = 0.009).Teeth retaining one (HR = 0.3; 95% CIor HR, 0.2 to 0.7; p = 0.004), two (HR =

0.2; 95% CI or HR, 0.1 to 0.5; p < 0.001),and three coronal walls (HR = 0.1; 95%CI or HR, 0.05 to 0.3; p < 0.001) hadsignicantly lower ailure risks than teethwithout a errule. Similar ailure risksexisted or teeth without coronal walls,regardless o the presence or absenceo a errule (p = 0.151). The interactionbetween the type o restoration and theamount o residual coronal dentin wasnot statistically signicant (p > 0.05).

DiscussionThe nding that the six-year survival

o the endodontically treated crownedpremolars was infuenced by the extento coronal tissue loss and by the presenceo a preabricated or a customized postrequires rejection o the null hypothesis.This outcome conrms the resultsreported previously at the three-yearrecall (Cagidiaco et al., 2008a). Amongthe clinical studies currently availableon ber post restorations, the present

investigation has the longest ollow-uptime. In line with the previous interimevaluation, intraradicular retention withLP resulted in a higher survival rate thanES. The stronger mechanical propertieso the preabricated post in comparisonwith the adapted ber bundle have beenadvocated as a possible explanation orthe more satisactory perormance osubgroup B restorations (Cagidiacoet al., 2008a). Even in the presence o


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Figure

Kaplan-Meier plots by restorative procedure (A) and by restorative procedure within each group (B-F).




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three coronal walls, ailure was identiedrom more than 20% o the restorations

ater 6 yrs o intra-oral unction, in teethwithout intraradicular retention and inthose with ES bers or retention.

Laboratory and clinical research hasshown that the amount o preservedcoronal tooth structure has a signicantinfuence on the ailure risk o post-endodontic restorations (Stankiewicz andWilson, 2002; Akkayan, 2004; Tan et al.,2005; Naumann et al., 2005a,b; Pereiraet al., 2006; Dietschi et al., 2007, 2008;Ferrari et al., 2007a; Cagidiaco et al.,

2008a,b; Juloski et al., 2011). Findingsrom the present study are conrmatory.In particular, the absence o a errule ina restored tooth imposed a signicantlyhigher risk o ailure than when at leastone coronal wall was retained.

Biomechanical issues in crownedteeth as well as the consideration thatadhesion to intraradicular dentin isless reliable than adhesion to coronaldentin may provide explanations or theincreased ailure risk in the presenceo reduced coronal structure. It should

be emphasized that, in this prospectiveclinical trial, the presence or absence oa errule produced similar outcomes interms o the survival probability o therestorations. This nding is not in linewith the bulk o evidence collected inprevious investigations on the erruleeect, suggesting that better prognosismay be expected i a 1.5- to 2-mm-highcircumerential dentin collar is maintainedcoronal to the crown margin (Stankiewicz

and Wilson, 2002; Dietschi et al., 2007;Juloski et al., 2011). As a possible

explanation or this discrepancy in results,it should be considered that teeth wereassigned to the dierent experimentalgroups based on the amount o coronaldentin let ater root canal treatmentand beore abutment preparation.Consequently, the loss o coronal toothstructure due to the preparation onishing margin and axial walls wasnot considered. Thus, the amount oerrule was probably overestimated inmany teeth that were assigned to Group

5. Likewise, group assignment beoreabutment preparation possibly resulted inoverestimation o the amount o dentinactually remaining at the coronal levelor all the teeth examined in the presentstudy. Based on these observations, itappears that the amount o tooth structurelet at the coronal level should be moreaccurately assessed ater abutmentpreparation in uture clinical studies.In particular, the errule should beevaluated with respect to its height andcircumerential extension. Although the

importance o this issue was highlightedin in vitro studies (Juloski et al., 2011),it has not been taken into account inclinical research. A better denition oexperimental groups should shed light onthe protective role o the errule in utureclinical studies.

Due to the relatively small samplesize in each subgroup, in this studywe did not attempt to adjust or basicconounders such as age, gender, and

type o premolar. Moreover, the presentstudy addressed only crowned premolars.

Further work should thereore be doneto obtain evidence-based inormationon the clinical outcome o teeth otherthan premolars and o ber-post-retainedrestorations unctioning as bridgeabutments. The lack o a power analysisor preliminary denition o the samplesize might appear as a limitation o thestudy. However, such omission wasjustied by the diculty in retrievingpremolars exhibiting dierent degrees ocoronal tissue loss.

In a recent publication, Zicari etal. (2011) advised that ailure criteriashould be clearly classied in clinicalprotocols dealing with post-endodonticrestorations. In agreement with thoseauthors suggestion, ailures in thepresent study were classied as absoluteor relative. Failure was considered asabsolute only in case o root racture.Such an event was regarded as acatastrophic ailure, since it committedthe tooth to extraction. The occurrenceo root ractures generated the survival

rate. Consequently, some groups hada 100% survival rate, despite events oendodontic ailure, crown dislodgement,post debonding, and post/core racture,since teeth that underwent theseoccurrences could be returned to clinicalunction through re-intervention. Inthe literature, ve-year survival rateso over 90% have been reported orimplants (Esposito et al., 1998; Berglundhet al., 2002) and or direct esthetic

Residual Coronal Dentin

No Post

(Subgroup A)

RTD Post

(Subgroup B)

EverStick Fibers

(Subgroup C)

Total

(perGroup)

(Group 1) 4 coronal walls Recall rate 17/19 (89.5%) 17/19 (89.5%) 17/19 (89.5%) 51/57 (89.5%)



(Group 4) 1 coronal wall Recall rate 16/19 (84.2%) 17/19 (89.5%) 16/19 (84.2%) 49/57 (85.9%)

(Group 5) Ferrule present Recall rate 18/20 (90%) 17/19 (89.5%) 14/20 (70%) 49/59 (83%)

(Group 6) Ferrule absent Recall rate 19/19 (100%) 17/19 (89.5%) 18/19 (94.7%) 54/57 (94.7%)

Total (persubgroup) Recall rate 104/115 (90.4%) 101/114 (88.6%) 98/115 (85.2%) 303/344 (88.1%)

Table 2.

Recall Rate o the Patients at the Six-year Follow-up Visit




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Table 3.

Recall Rates, Distribution o Failure Modes, Success Rates, and Survival Rates Recorded or Crowned Endodontically Treated Premolars

Followed over Six Years o Clinical Service

Residual

Coronal Dentin

No Post

(Subgroup A)

RTD Post

(Subgroup B)

EverStick Fibers

(Subgroup C)

Total

(perGroup)

(Group 1)

4 coronal walls

Recall rate 17/20 (85%) 18/20 (90%) 18/20 (90%) 53/60 (88.3%)

Failures No ailure (0%) No ailure (0%) No ailure (0%) 0%

Success rate 100% 100% 100% 100%

(Group 2)

3 coronal walls

Recall rate 18/20 (90%) 17/20 (85%) 17/20 (85%) 52/60 (86.7%)

Failures 3 endodontic ailures (16.6%)

3 crown dislodgements (16.6%)

1 post debonding (5.8%) 2 endodontic ailures (11.7%)

2 post/core ractures (11.7%)

21.1%

Success rate 66.7% 94.1% 76.5% 78.8%

Survival rate 100% 100% 100% 100%

(Group 3)

2 coronal walls

Recall rate 17/20 (85%) 18/20 (90%) 18/20 (90%) 53/60 (88.3%)

Failures 2 endodontic ailures (11.7%)

1 root racture (5.8%)


1 endodontic ailure

(5.5%)

1 post racture (5.5%)

2 endodontic ailures (18.2%)



30.2%

Success rate 52.9% 88.9% 66.7% 69.8%

Survival rate 94.1% 100% 100% 91.2%

(Group 4)

1 coronal wall

Recall rate 17/20 (85%) 18/20 (90%) 16/20 (80%) 51/60 (85%)

Failures 3 root ractures (17.6%)



3 post debondings (16.6%)

1 endodontic ailure (5.5%)




47%

Success rate 29.4% 77.8% 50.0% 52.9%

Survival rate 82.4% 100% 100% 94.1%

(Group 5)

Ferrule present

Recall rate 18/20 (90%) 18/20 (90%) 14/20 (70%) 50/60 (83.3%)

Failures 4 root ractures (22.2%)


9 crown dislodgements (50%)

1 post racture (5.5%)






66%

Success rate 11.1% 61.1% 28.5% 34%

Survival rate 77.8% 100% 100% 92.6%

(Group 6)

Ferrule absent

Recall rate 20/20 (100%) 18/20 (90%) 19/20 (95%) 57/60 (95%)

Failures 7 root ractures (35%)

4 endodontic ailures (20%)


1 root racture (5.5%)




3 root ractures (15.7%)




77.2%

Success rate 0% 38.9% 31.6% 22.8%

Survival rate 65% 94.4% 84.2% 80.7%

Total

(persubgroup)

Recall rate 107/120 (89.2%) 107/120 (89.2%) 102/120 (85%) Grand total,

316/360 (87.7%)

Success rate 42.1% 76.6% 61.3% 60%

Survival rate 85.9% 99.1% 97.2% 94.1%




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restorations (Manhart et al., 2004). Nosuch inormation is available or post-endodontic restorations. Analysis o thedata collected in the present investigationindicated that over 90% o single crownsretained by preabricated ber posts

were in clinical service six years aterplacement. However, the percentage oailure-ree restorations (success rate)decreased drastically in the absence oa residual coronal wall. The decline insuccess rates or teeth deprived o anycoronal wall was even sharper i the teethhad been restored with customized postsor without intraradicular retention. Undersuch conditions, alternative strategies,such as crown lengthening or implantreplacement, should be considered.

In conclusion, over a six-year

observation period, the placement o apreabricated or a customized post wasshown to contribute signicantly to thesurvival o pulpless restored premolars.This contribution was more eectiveor LP than or ES. Regardless o therestorative procedure, preservation oat least one coronal wall signicantlyreduced the ailure risk.

Acknowledgments

The authors received no nancialsupport and declare no potential confictso interest with respect to the authorshipand/or publication o this article.

ReferencesAkkayan B (2004). An in vitro study evaluating

the eect o errule length on racture resi-stance o endodontically treated teeth resto-red with ber-reinorced and zirconia dowelsystems.J Prosthet Dent92:155-162.

Aquilino SA, Caplan DJ (2002). Relationship bet-ween crown placement and the survival oendodontically treated teeth.J Prosthet Dent87:256-263.

Berglundh T, Persson L, Klinge B (2002). A syste-matic review o the incidence o biologicaland technical complications in implant den-tistry reported in prospective longitudinalstudies o at least 5 years. J Clin Periodontol29(Suppl 3):197-212.

Bolla M, Muller-Bolla M, Borg C, Lupi-Pegurier L,Laplanche O, Leorestier E (2007). Root canalposts or the restoration o root lled teeth.Cochrane Database Syst Rev1:CD004623.

Cagidiaco MC, Garca-Godoy F, Vichi A, GrandiniS, Goracci C, Ferrari M (2008a). Placemento ber preabricated or custom madeposts aects the 3-year survival o endodon-tically treated premolars.Am J Dent21:179-184.

Cagidiaco MC, Goracci C, Garcia-Godoy F,

Ferrari M (2008b). Clinical studies o berposts: a literature review.Int J Prosthodont21:328-336.

Caplan DJ, Kolker J, Rivera EM, Walton RE(2002). Relationship between number o pro-ximal contacts and survival o root canaltreated teeth.Int Endod J35:193-199.

Dietschi D, Duc O, Krejci I, Sadan A (2007).Biomechanical considerations or the resto-ration o endodontically treated teeth: asystematic review o the literaturePart 1.Composition and micro- and macrostructurealterations. Quintessence Int38:733-743.

Dietschi D, Duc O, Krejci I, Sadan A (2008).

Biomechanical considerations or the resto-ration o endodontically treated teeth: asystematic review o the literature, PartII (Evaluation o atigue behavior, inter-aces, and in vivo studies). Quintessence Int39:117-129.

Esposito M, Hirsch J, Lekholm U, Thomsen P(1998). Biological actors contributing to ai-lures o osseointegrated implants. I. Successcriteria and epidemiology.Eur J Oral Sci106:527-551.

Ferrari M, Vichi A, Mannocci F, Mason PN(2000a). Retrospective study o the clini-cal perormance o ber posts.Am J Dent13

(Spec No):9B-13B.Ferrari M, Vichi A, Garcia-Godoy F (2000b).

Clinical evaluation o ber-reinorced epoxyresin posts and cast post and cores. Am J

Dent13 (Spec No):15B-18B.

Ferrari M, Cagidiaco MC, Goracci C, VichiA, Mason PN, Radovic I, et al. (2007a).Long-term retrospective study o the clini-cal perormance o ber posts.Am J Dent20:287-291.

Ferrari M, Cagidiaco MC, Grandini S, De SanctisM, Goracci C (2007b). Post placement aectssurvival o endodontically treated premolars.

J Dent Res86:729-734.

Fredriksson M, Astback J, Pamenius M, ArvidsonK (1998). A retrospective study o 236 pati-ents with teeth restored by carbon ber-rein-orced epoxy resin posts.J Prosthet Dent80:151-157.

Glazer B (2000). Restoration o endodonticallytreated teeth with carbon bre postsa pro-spective study.J Can Dent Assoc 66:613-618.

Goracci C, Ferrari M (2011). Current perspecti-ves on post systems: a literature review.AustDent J56(Suppl 1):77-83.

Juloski J, Radovic I, Goracci C, Vulicevic ZR,Ferrari M (2011). Ferrule eect: a literaturereview.J Endod38:11-19.

Malerrari S, Monaco C, Scotti R (2003). Clinicalevaluation o teeth restored with quartzber-reinorced epoxy resin posts. Int J

Prosthodont16:39-44.

Mancebo JC, Jimnez-Castellanos E, Caadas D(2010). Eect o tooth type and errule onthe survival o pulpless teeth restored withber posts: a 3-year clinical study.Am J Dent23:351-356.

Manhart J, Chen H, Hamm G, Hickel R (2004).Buonocore Memorial Lecture. Review o theclinical survival o direct and indirect resto-rations in posterior teeth o the permanentdentition. Oper Dent29:481-508.

Mannocci F, Bertelli E, Sherri M, Watson TF,Ford TR (2002). Three-year clinical compa-rison o survival o endodontically treatedteeth restored with either ull cast coverage

or with direct composite restoration.J Prosthet Dent88:297-301.

Monticelli F, Grandini S, Goracci C, Ferrari M(2003). Clinical behavior o translucent-ber posts: a 2-year prospective study.Int J


Naumann M, Blankenstein F, Dietrich T (2005a).Survival o glass bre reinorced compositepost restorations ater 2 yearsan observa-tional clinical study.J Dent33:305-312.

Naumann M, Blankenstein F, Kiessling S, DietrichT (2005b). Risk actors or ailure o glassber-reinorced composite post restorations:a prospective observational clinical study.

Eur J Oral Sci113:519-524.

Pereira JR, de Ornelas F, Conti PC, do Valle AL(2006). Eect o crown errule on the rac-ture resistance o endodontically treatedteeth restored with preabricated posts.

J Prosthet Dent95:50-54.

Stankiewicz NR, Wilson PR (2002). The er-rule eect: a literature review.Int Endod J35:575-581.

Tan PL, Aquilino SA, Gratton DG, Stanord CM,Tan SC, Johnson WT, et al. (2005).In vitroracture resistance o endodontically treatedcentral incisors with varying errule heights

and congurations.J Prosthet Dent93:331-336.Zhi-Yue L, Yu-Xing Z (2003). Eects o post-core

design and errule on racture resistance oendodontically treated maxillary central inci-sors.J Prosthet Dent89:368-373.

Zicari F, Van Meerbeek B, Debels E, Lesare E,Naert I (2011). An up to 3-year controlled cli-nical trial comparing the outcome o glassber post and composite cores with goldalloy-based posts and cores or the resto-ration o endodontically treated teeth.Int J




ferrari 2012. randomized clinical trial

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