Prevalência de lesões associadas a terceiros molares impactados em radiografias panorâmicas

Abstract

Background: Prophylactic extraction of third molars (3M) is a controversy in Dentistry. Despite the lack of consensus, the extraction of asymptomatic 3M is still recommended, justified by the risks of developing pathologies due to the maintenance of the impacted tooth. Aim: To evaluate the prevalence of pathologies associated with impacted 3M, and other radiographic characteristics of these teeth, on panoramic radiographs. Methodology: Panoramic radiographs with the presence of impacted 3M (upper or lower), from the Nolla’s stage 7, were evaluated. Variables tooth positioning, tooth development, presence of changes in the second molar, and patient demographic data were collected. A trained and calibrated examiner (Intraclass Correlation Coefficient = 0.97 and Kappa Index = 0.88 - 1) evaluated all images. The outcome was the presence of pathologies related to the impacted 3M. Descriptive analysis was performed, and binary and multivariate logistic regression models were used to assess the association between the outcome and the other local (relative to the tooth) and demographic (relative to the patient) variables. A significance level of 0.05 was considered in the multivariate model. Results: The sample consisted of panoramic radiographs from 2054 patients, mostly female (59.8%), with a mean age of 27.2 ± 11.5 years. 4066 3M were evaluated and 483 pathologies (11.9%) were identified in 457 (22.25%) patients, of which 460 (95.2%) were suggestive of a dentigerous cyst. Male gender, lower 3M, vertical or distoangular positioning, and incomplete root formation were more likely to have an associate pathology. Conclusion: The prevalence of radiographic changes compatible with developmental pathologies in impacted 3M is low, but teeth with some local characteristics were more likely to present a pathology, emphasizing the value of clinical and especially radiographic follow-up of impacted teeth.