A Retrospective Brazilian Multicenter Study of Biopsies at the Periapical Area: Identification of Cases of Nonendodontic Periapical Lesions.

Introduction: The purpose of this study was to analyze the features of lesions obtained from biopsies at the periapical area of teeth with a radiographic or clinical initial diagnosis of apical periodontitis.

Methods: A retrospective study was conducted on biopsies obtained from 1953-2018 at 3 Brazilian oral and maxillofacial pathology centers. Cases of endodontic and nonendodontic periapical lesions (NPLs) with a clinical diagnosis of endodontic pathoses were retrieved. Data regarding patient age, sex, and anatomic location were obtained from patients' records. The frequency and percentage of cases with clinical diagnoses of a periapical cyst, periapical granuloma, or dentoalveolar abscess were recorded, and the final histopathologic diagnosis was documented.

Results: Among 66,179 oral biopsies, 7246 (10.94%) were clinically diagnosed as periapical disease, 306 (4.22%) of which were histopathologically diagnosed as NPLs. The most frequent NPLs were odontogenic keratocysts (n = 107, 34.96%) followed by dentigerous cysts (n = 48, 15.68%). The mean age at diagnosis was 39.68 years with a range of 6-80 years. A total of 159 (51.96%) cases occurred in females and 147 (48.03%) in males (female to male ratio = 1.08:1). Most lesions (137, 44.77%) were located in the posterior mandible.

Conclusions: A wide variety of histopathologic diagnoses, including benign odontogenic and nonodontogenic cystic and tumorous lesions, infectious diseases, and malignant neoplasms, was reported in the present survey. The features presented in this study were consistent with previous findings reported in the literature.