Demographic profile of odontogenic and selected nonodontogenic cysts in a Brazilian population Soraya M. Grossmann, DDS, MSD, a Vinícius C. Machado, DDS, b Guilherme M. Xavier, DDS, b Mariela D. Moura, DDS, MSD, a Ricardo S. Gomez, DDS, MSD, PhD, c Maria Cássia F. Aguiar, DDS, MSD, PhD, c and Ricardo A. Mesquita, DDS, MSD, PhD, c Belo Horizonte, Brazil DEPARTMENT OF ORAL SURGERY, ORAL MEDICINE, AND ORAL PATHOLOGY, FACULTY OF ODONTOLOGY, FEDERAL UNIVERSITY OF MINAS GERAIS Objective. To determine the demographic profile of all histologically diagnosed odontogenic cysts (OC) and nonodontogenic cysts (nOC) over a 51-year period in the Brazilian population. Study design. Case records of patients with OC and nOC from the files of the Oral Pathology Service, School of Dentistry, Federal University of Minas Gerais, Belo Horizonte, Brazil, during the period of 1953-2003 were evaluated. Results. Among 19,064 oral biopsies, 2,905 (15.2%) presented criteria of OC and nOC. Of these, 2,812 specimens (14.7%) were diagnosed as OC and 93 (0.5%) represented nOC. The 3 most frequent OC diagnosed were radicular cyst (61.0%), dentigerous cyst (25.3%), and odontogenic keratocyst (7.2%). The most frequent nOC was the nasopalatine duct cyst (2.2%). Conclusion. Our results demonstrate that there is a wide range of OC and nOC, with some cysts having a predilection for age, gender, and localization. We also showed demographic aspects and clinical characteristics of these cysts. These could be used as baseline data to obtain more epidemiologic information about the OC and the nOC especially in the Brazilian population. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2007;104:e35-e41) Cysts represent a pathologic cavity surrounded by ep- ithelium, with a fluid or semisolid material in its inte- rior. The jaws play host to a wide variety of cysts, owing to the epithelial tissues involved in odontogen- esis. 1 The odontogenic cysts (OC) are osseous-destruc- tive lesions which more commonly affect the jaws. 2 They develop from the epithelial components of the odontogenic apparatus, or its remnants, that lie en- trapped within the bone or in the gingival tissue. It is considered that proliferation and cystic degeneration of this epithelium leads to the development of OC. 3,4 Epithelial remnant proliferations of nonodontogenic or- igin are responsible for the formation of nonodonto- genic cysts (nOC). 5 The OC and nOC show varied histogenesis, relative rates of frequency, clinical features, and biologic be- havior. Some of these diseases are innocuous, whereas others can behave in an aggressive and destructive fashion. 3 The biologic behavior of the jaw cysts is related to recurrence and/or aggressive growth. 1 Demographic profiles on odontogenic cysts have been performed in populations from Canada, 2 Mexi- co, 4-6 Germany, 7 and the United Kingdom. 8 Records concerning the prevalence of the main types of cysts are important and thus kept by government or health care institutes in most countries. The records of oral pathol- ogy services are the main sources of information about oral lesions. 9-14 Information about OC and nOC from different pop- ulations is scarce and there are few studies available regarding the occurrence of these lesions in the Latin American population. 11,12 The purpose of the present study was to determine the range of all histologically diagnosed OC and nOC along with age, gender, local- ization, and recurrence over a 51-year period in the Brazilian population. MATERIALS AND METHODS The study protocol was approved by the Committee of Bioethics in Research from the School of Dentistry, Federal University of Minas Gerais (FO-UFMG), Belo Horizonte, Brazil (Number 208/04). From the Oral Pathology Service files at FO-UFMG, records of 19,064 samples of oral biopsies were re- trieved. This service is one of the referral centers in oral This study was supported by grants from CAPES, FAPEMIG (CDS 895/05), and CNPq (484974/2006-8). R.S. Gomez, M.C.F. Aguiar, and R.A. Mesquita are research fellows of CNPq. a Undergraduate student. b Graduate student. c Professor. Received for publication Feb 23, 2007; returned for revision May 20, 2007; accepted for publication May 22, 2007. 1079-2104/$ - see front matter © 2007 Mosby, Inc. All rights reserved. doi:10.1016/j.tripleo.2007.05.028 e35