Odontogenic cysts: a clinicopathological study of 507 cases.

The purpose of this study was to determine the prevalence of odontogenic cysts at the Pernambuco School of Dentistry - Universidade de Pernambuco (Brazil) and compare this prevalence with other international studies. Data for the study were obtained from reports of patients diagnosed with odontogenic cysts between 1992 and 2007. Case records of patients who fit the Histological Classification of the World Health Organization (2005) were included. The following variables were analyzed: gender, age group, anatomical location, histological type and ethnic background. Odontogenic cysts accounted for 9.94% of all lesions biopsied throughout the study period. Mean patient age was 28.9 years and 57.6% of the patients were males (P > 0.05). Radicular cyst was the most prevalent histological type (52.2%), followed by dentigerous cyst (30.7%). Regarding ethnic background, 41.8 % of the patients were of African descent, followed by Caucasians and other ethnic groups (P > 0.05). The mandible was the most prevalent site of the lesions (56%). Odontogenic cysts appear to have a distinct predilection for the male gender, the second and third decades of life (P < 0.05) and are more frequent in the mandible. The removal of odontogenic keratocysts from the new WHO classification has not altered the order of the most prevalent cysts in the maxillofacial complex.