A study of cysts in the oral region. Cysts of the jaw.

Clinical cases of cysts of the jaw treated in the Department of Oral Surgery of our university during the 10 y between 1980 and 1989 were studied clinically. Patients with radicular cyst, dentigerous cyst, odontogenic keratocyst and postoperative maxillary cyst, which were found at relatively high frequencies, were further analyzed with regard to age, sex and anatomical distribution. A diagnosis of cyst was established in 1,444 patients during the above period, and 1,234 (85.5%) of them had cysts of the jaw. According to a pathological classification by Ishikawa's method, these patients included 509 (41.2%) with radicular cyst, 259 (27.0%) with dentigerous cyst, 95 (7.7%) with odontogenic keratocyst and 267 (21.6%) with postoperative maxillary cyst. The pattern of age distribution in cases of radicular cyst, odontogenic keratocyst and postoperative maxillary cyst was similar to that found in previous studies. Among patients with dentigerous cyst, those aged under 20 y accounted for about 60%. Radicular cyst occurred most frequently in the maxillary lateral incisors, dentigerous cyst in the mandibular wisdom teeth, and odontogenic keratocyst in the region between the mandibular molar and the ramus of the mandible.