Endodontics| Volume 93, ISSUE 5, P596-604, May 2002

Survival of first-time nonsurgical root canal treatment performed in a dental teaching hospital


      Objective. The purpose of this study was to use survival analysis to evaluate the long-term treatment outcome of first-time, nonsurgical root canal therapy performed in a dental teaching hospital and to identify factors that might affect that outcome. Study Design. One-tenth of all teeth treated between 1989 and 1994 were sampled. Patients were invited to return for a recall and were examined both clinically and radiographically. Any teeth that had been extracted or retreated or that were associated with a periapical radiolucency or presented with clinical signs and symptoms were deemed to have failed. An adjusted date of failure was calculated in the survival analysis by means of the Kaplan-Meier method. Ten covariables were further analyzed with the Cox regression model by using a backward stepwise regression method. Results. Of 550 sampled teeth, 251 were examined. The mean observation period was 74 months. The failure rate was 44% (n = 111), with a median survival time of 113 months (mean, 91 months). Use of the Cox Regression model revealed that tooth type was significant in affecting the survival time of the treatment. Radiographic presence of voids in the apical and middle thirds of root canal fillings was associated with a significantly lower mean survival time than the presence of voids found in the coronal third or no void at all. The use of a calcium hydroxide dressing after initial treatment was associated with a longer survival time than failure to use medication or dressing with Ledermix alone. Conclusion. Simple calculation of percentages did not provide sufficient information on the treatment prognosis. The survival of first-time root canal therapy was significantly influenced by the tooth type, radiographic location of voids in the root canal filling, and the intracanal medicament used. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2002;93:596-604)
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        • Friedman S.
        Treatment outcome and prognosis of endodontic therapy.
        in: Essential Endodontology. : Blackwell Science, Malden1998: 367-401
        • Weiger R
        • Axmann-Krcmar D
        • Löst C.
        Prognosis of conventional root canal treatment reconsidered.
        Endod Dent Traumatol. 1998; 14: 1-9
        • Ørstavik D.
        Time-course and risk analyses of the development and healing of chronic apical periodontitis in man.
        Int Endod J. 1996; 29: 150-155
        • Hayes SJ
        • Dummer PM.
        Late failure of root canal therapy: a diagnostic and treatment planning challenge. Case report.
        Int Endod J. 1997; 30: 68-71
        • Saunders WP
        • Saunders EM.
        Coronal leakage as a cause of failure in root canal therapy.
        Endod Dent Traumatol. 1994; 10: 105-108
        • Tronstad L
        • Asbjørnsen K
        • Døving L
        • Pedersen I
        • Eriksen HM.
        Influence of coronal restorations on the periapical health of endodontically treated teeth.
        Endod Dent Traumatol. 2000; 16: 218-221
        • Lin LM
        • Pascon EA
        • Skribner J
        • Gängler P
        • Langeland K.
        Clinical, radiographic, and histologic study of endodontic treatment failures.
        Oral Surg Oral Med Oral Pathol. 1991; 11: 603-611
        • European Society of Endodontology
        Consensus report of the European Society of Endodontology on quality guidelines for endodontic treatment.
        Int Endod J. 1994; 27: 115-124
        • Anderson JD
        • Zarb GA.
        Evidence-based dentistry: prognosis.
        J Prosthet Dent. 2000; 83: 495-500
        • Bryne M
        • Eide GE
        • Lilleng R
        • Langmark F
        • Thrane PS
        • Dabelsteen E.
        A multivariate study of the prognosis of oral squamous cell carcinomas. Are blood group and hemoglobin new prognostic factors?.
        Cancer. 1991; 68: 1994-1998
        • Lee ET
        • Go OT.
        Survival analysis in public health research.
        Ann Rev Pub Health. 1997; 18: 105-134
        • Bjertness E
        • Sonju T.
        Survival analysis of amalgam restorations in long-term recall patients.
        Acta Odontol Scand. 1990; 48: 93-97
        • Weyant RJ
        • Burt BA.
        An assessment of survival rates and within patient clustering of failures for endosseous oral implants.
        J Dent Res. 1993; 72: 2-8
        • Creugers NHJ
        • De Kanter RJ
        • van't Hof MA.
        Long-term survival data from a clinical trial on resin-bonded bridges.
        J Dent. 1997; 25: 39-42
        • Mitchell L
        • Walls AWG.
        Survival analysis in practice.
        Dent Update. 1991; 18: 125-128
        • Parmar MKB
        • Machin D.
        Life table estimate of survival function compared to Kaplan-Meier estimate.
        in: Survival analysis: a practical approach. : John Wiley & Sons, Chichester1995: 21-51
        • SPSS Inc
        SPSS Advanced Models™ 10.0.
        (Chapters 10 and 21)in: : SPSS Inc, Chicago1999: 83-89 (and 283-311)
        • Reit C.
        Decision strategies in endodontics: On the design of a recall program.
        Endod Dent Traumatol. 1987; 3: 233-239
        • Smith CS
        • Setchell DJ
        • Harty FJ.
        Factors influencing the success of conventional root canal therapy—a five-year retrospective study.
        Int Endod J. 1993; 26: 321-333
        • Tse CM.
        A study of conventional root canal therapy performed by dental students.
        MDS thesis, Faculty of Dentistry, The University of Hong Kong, Hong Kong, 1990
        • Bender IB
        • Seltzer S
        • Soltanoff W.
        Endodontic success —a reappraisal of criteria. I and II.
        Oral Surg Oral Med Oral Pathol. 1966; 22: 780-802
        • Reit C
        • Grondahl HG.
        Management of periapical lesions in endodontically treated teeth. A study on clinical decision making.
        Swed Dent J. 1984; 8: 1-7
        • Hülsmann M.
        Retreatment decision making by a group of general dental practitioners in Germany.
        Int Endod J. 1994; 27: 125-132
        • Kvist T
        • Reit C
        • Esposito M
        • Mileman P
        • Bianchi S
        • Pettersson K
        • et al.
        Prescribing endodontic retreatment: towards a theory of dentist behaviour.
        Int Endod J. 1994; 27: 285-290
        • Brynolf I.
        A histological and roentgeenological study of the periapical region of human upper incisors.
        Odontol Revy. 1967; 18: 1-176
        • Byström A
        • Sundqvist G.
        Bacteriology evaluation of the efficacy of mechanical root canal instrumentation in endodontic therapy.
        Scand J Dent Res. 1981; 89: 321-328
        • Byström A
        • Sundqvist G.
        The antibacterial action of sodium hypochorite and EDTA in 60 cases of endodontic therapy.
        Int Endod J. 1985; 18: 35-40
        • Sjögren U
        • Fidgor D
        • Persson S
        • Sundqvist G.
        Influence of infection at the time of root filling on the outcome of endodontic treatment of teeth with apical periodontitis.
        Int Endod J. 1997; 30: 297-306
        • Sjögren U
        • Figdor D
        • Spångberg L
        • Sundqvist G.
        The antimicrobial effect of calcium hydroxide as a short-term intracanal dressing.
        Int Endod J. 1991; 24: 119-125
        • Abbott PV.
        Recognition and prevention of failures in clinical dentistry.
        Ann R Aust Coll Dent Surg. 1991; 11: 150-166