Objectives: Retrospective description of the 10-year success rate of endodontic treatments with Thermafil (TF).
Materials and methods: Patients treated by postgraduate students in an Endodontics Master's Program (2006-2008) were enrolled. All treated root canals were filled with TF and AH Plus. Teeth satisfying the inclusion criteria (206 teeth in 89 patients) were reexamined clinically and radiographically to estimate a 10-year survival and periapical health. Demographic and medical data were registered; collected information included pre-, intra-, and postoperative variables. Teeth were classified as "healthy" (PAI ≤ 2 in absence of signs/symptoms), "endodontically diseased" (presenting at least one of the following: PAI ≥ 3, signs/symptoms, retreated in the course of the follow-up, or extracted for endodontic reasons), or "non-endodontically diseased" (extracted for non-restorable fractures or periodontal disease). For teeth lost during the 10-year follow-up, details and reason of extraction were analyzed. Two PAI-calibrated examiners assessed outcomes blinded to preoperative status. Bivariate and multilevel analyses were performed (α level set at 0.05).
Results: At 10 years, 179 (87%) teeth survived and 27 were extracted: 20 for non-endodontic reasons (excluded from success analysis) and 7 for endodontic reasons (considered "endodontically diseased"). Multilevel analysis revealed that the probability of extraction was increased by the presence of preoperative pain (odds ratio = 6.720; 95% confidence interval, 1.483-30.448) and by maxillary location (odds ratio = 2.950; 95% confidence interval, 1.043-8.347). Concerning periapical status, 159/186 teeth (85%) were assessed as "healthy." Multilevel analysis confirmed that maxillary location (odds ratio = 3.908; 95% confidence interval, 1.370-11.146), presence of flare up (odds ratio = 9.914; 95% confidence interval, 2.388-41.163), and fracture occurrence (odds ratio = 35.412; 95% confidence interval, 3.366-372.555) decreased the odds of healing, respectively.
Conclusions: After 10 years, teeth filled with Thermafil in a specialist master's program presented a survival and a periapical health comparable to cohorts where root canals were filled with other obturation techniques.
Clinical relevance: Carrier-based techniques provide time savings for clinicians while satisfying clinical quality criteria for the root filling and consequently the clinical outcome.
Keywords: Carrier-based system; Clinical outcome; Long term; Retrospective study; Survival.