Long-term Retrospective Analysis of Root Canal Treatments

Objectives: Only few information is available on endodontically treated teeth after more than 10 years. The reason of failure and the typology of new endodontic lesions is not well documented. The goal of the present retrospective study is to investigate the percentage of endodontically-treated teeth still healthy after an observational time of approximately 18 years.
Methods: Sixty patients received one or more root-canal treatment between April 1990 and November 1996. Twenty-one patients were excluded because they could not be contacted.One patient deceased: drop-out consisted of 37%. One-hundred eleven root-treated teeth (n=38 patients: 20-females and 18-males; mean-age 44±10 years) met inclusion criteria. Four groups were established on the basis of radiographic presence/absence of initial-apical-periodontitis (IAP) and clinical data: vital-pulp (39.91%), pulpitis (50.4%) (both without IAP), (necrotic teeth with) periapical-lesion (14.5%) and retreatment (4.27%) (both with IAP). Root canals were prepared using stainless-steel files (FKG, La Chaux-de-Fonds, Switzerland) with step-back technique. Five mL of 5% NaOCl (Niclor-5, OGNA, Muggiò, Italy) and H2O2 (OGNA, Muggiò, Italy) were used as irrigants. Compacted-warm guttapercha points (Coltene/Whaledent-inc., Cuyahoga-Falls, OH, USA) and CRCS sealer (Coltene/Whaledent-inc., Cuyahoga-Falls, OH, USA) filled the canals. Metal-ceramic crowns were provided. Intra-oral radiographs were taken pre-operatively, post-operatively, at end-point and blindly twice evaluated by two examiners. Mean-observation time was 18.55 ± 2.2 years.
Results: Periapical status was classified at the end-point on the basis of the Toronto study criteria and dichotomized. Final survival rate was 80.64%. Percentage of healthy teeth was 68.48% (Table 1). Extraction data were recorded (Table 2).
Conclusions: Survival rate is according with data reported by literature. Teeth treated for pulpitis are less subject to long term complications. Teeth treated for prosthetic reasons are related to a less favorable outcome: a higher possibility of periodontal loss was observed.