Morfologia radicular de dentes fusionados - um estudo observacional por meio de uma visão bidimensional

Abstract

Objective: To identify the prevalence of root fusion in maxillary and mandibular first and second permanent molars, as well as to investigate sexual dimorphism in the presence of fused roots in a large sample of Brazilian individuals. Methodology: Observational study, based on the analysis of digital panoramic radiographs from a dental radiology clinic in Curitiba (Paraná, Brazil). Patients of both sexes, aged between 11 and 73 years, who presented all first and second permanent molars intact (eight molars), at Nolla stages 9 and/or 10, were included. Radiographs with previous endodontic treatment, prosthetic crowns, primary teeth, third molars or supernumerary teeth, extensive metallic restorations, fractures, root resorptions or resections, absence of a visible clinical crown, as well as patients with syndromes and cleft lip and/or palate, were excluded. The images were obtained with an Axeos device and analyzed using Sidexis 4 software. Molars were considered to present root fusion when the roots were united apically to the furcation, with no radiographic evidence of periodontal ligament space or bone between them. Statistical analysis was performed using SPSS, applying the chi-square test and odds ratio (OR) with a 95% confidence interval to compare the presence of fusion between sexes, and the t-test to compare the mean number of affected teeth (p< 0.05). Results: A total of 872 panoramic radiographs were included, corresponding to 337 men and 495 women, with 6,976 molars evaluated. The presence of at least one molar with fused roots was observed in 260 individuals, resulting in an overall prevalence of 29.8%. The prevalence was 26.7% in men and 34.3% in women. Women had a statistically higher probability of presenting root fusion in molars than men (p=0.0008; OR=1.66; 95% CI: 1.23-2.25). Conclusion: Root fusion in permanent molars showed a sex-related variation in prevalence, being more frequent and more extensive in females. These findings suggest a sex-specific predisposition to the development of fused roots, possibly related to genetic factors and the influence of sex chromosomes on root formation.