Pattern of odontogenic and nonodontogenic cysts.

The jaws are host to a variety of cysts due in large part to the tissues involved in tooth formation. Odontogenic cysts (OCs) are unique in that they affect only the oral and maxillofacial region. There are few studies from sub-Saharan Africa. This study was aimed at describing the pattern of various types of cysts in the oral and maxillofacial region in a Kenyan population. This was done at the Departments of Oral and Maxillofacial Surgery and Oral Medicine and Pathology, University of Nairobi Dental Hospital. This was a retrospective audit. All histopathologic records were retrieved from 1991 to 2010 (19 years) and were counted. The following information was extracted and recorded in a data sheet: age, sex, and the type of cystic lesions. There were 194 cysts (4.56%) diagnosed of 4257 oral and maxillofacial lesions. Of these, 64.4% were from male and 35.6% were from female patients with an age range of 1 to 70 years (mean, 23.76 [SD, 14.05] years; peak and median of 20 years). The most common OCs (57.2%) were dentigerous and radicular, whereas the most common nonodontogenic cyst (42.8%) was nasopalatine duct cyst. Other soft tissue cysts reported were epidermoid, branchial, thyroglossal, dermoid, and cystic hygroma. Oral and maxillofacial cysts are not uncommon in this population, the majority being the OC, dentigerous cyst, followed by the nonodontogenic cyst, nasopalatine cyst. The cysts are male predominant and occur 10 to 15 years earlier compared with those in the white population.