Survival and periapical health after root canal treatment with carrier‐based root fillings: five‐year retrospective assessment

Aim This retrospective study explored survival and periapical healing outcomes in root filled teeth with Thermafil obturators. Methodology Root canals of 213 teeth (94 subjects, mean age 48±13 years), instrumented with a step-down technique, irrigated with 5% NaOCl and 10% EDTA and filled with Thermafil and AH-Plus sealer, were involved in a Recall programme. Teeth were retrospectively reexamined after 5±1 years in a controlled environment. Clinical and radiographic data that were collected included: preoperative Periapical Index (PAI) score and signs/symptoms, treatment type, root filling length and presence/absence of voids, restoration type, follow-up PAI score and signs/symptoms. Teeth were considered ‘healthy’ (PAI≤2, no signs/symptoms) or ‘diseased’ (PAI ≥ 3, signs/symptoms present, retreated, extracted for endodontic reasons). Two PAI-calibrated examiners assessed outcomes blinded to preoperative status. Bivariate and multilevel analyses were performed at level of patient and tooth (α = 5%). Results Of 213 teeth treated, 187 (88%) survived and 26 were extracted, 6 (3%) for persistent endodontic infection (considered ‘diseased’), and 20 (9%) for root fracture, periodontal disease or coronal fracture (excluded from analysis). While survival was significantly associated with tooth type (p=0.015), type of treatment (p=0.012) and pulpal/periapical diagnosis (p=0.035), none of these variables were substantiated as survival predictors by the multilevel analysis. A total of 164/193 teeth (85%) were assessed as ‘healthy’, with significantly higher (Chi-square; p < 0.04) ‘healthy’ rates for teeth with PAI score ≤2 and root-fillings of adequate length. Multilevel analysis identified PAI score ≤2 (p=0.002) as the only predictor of periapical health. Conclusions In this 5±1 year retrospective assessment, survival and healing rates after root canal treatment with Thermafil root fillings were comparable to those previously reported for conventional root filling techniques This article is protected by copyright. All rights reserved.