Periapical Complications Associated with Tooth-Supported Fixed Dental Prostheses: A Long-Term Clinical Evaluation

Objectives: Endodontic complications are among the most frequently reported biological complications in tooth-supported fixed dental prostheses (FDPs). The aim of this study was to evaluate the prevalence of periapical complications in FDPs placed on vital and non-vital abutments and to identify risk factors for these lesions. Methods: This retrospective clinical trial was conducted on participants who had attended routine follow-up visits at the dental hospital at Qassim University, Saudi Arabia. Participants were examined clinically and radiographically for the presence of periapical lesions. Information was recorded on the design, material, location of the prostheses, and oral hygiene. The survival and lesion-free survival rates were determined using the Kaplan–Meier method. Life-table analysis was performed to assess the mean time to event. Univariate Cox proportional hazards regression analysis was used to assess potential risk factors for the development of periapical lesions (α = 0.05). Results: A total of 495 FDPs were placed in 302 participants, with a mean age of 45.7 ± 13.4 years and a mean follow-up period of 7.5 ± 6.5 years. Lesions were detected in 32.3% of FDPs during follow-up. There were no significant differences in the prevalence of lesions in vital compared with non-vital abutments or between males and females (p > 0.05). Poor oral hygiene was the most significant risk factor for the development of periapical lesions (p < 0.05). Univariate Cox regression analysis showed that anterior–posterior FDPs had a higher risk of lesions (p = 0.035). No significant associations were found between lesions and the material used or the design of the abutment (p > 0.05). Conclusions: Periapical complications in FDPs are mainly influenced by oral hygiene and the location of the FDPs, whereas abutment vitality and material type appear to have limited impact.