Peripheral (extraosseous) calcifying odontogenic cyst. A review of forty-five cases.

The peripheral calcifying odontogenic cyst (PCOC) is a rare lesion. The number of well-documented cases reported in the English-language literature until now is 38. The purpose of the present study is twofold: (1) to report seven new cases of PCOC and (2) to review and analyze the clinical and histomorphologic features of the previously reported cases of PCOC together with those of the present study. Most of the lesions were located in the maxillary and mandibular gingiva or alveolar mucosa anterior to the region of the first molar. Histologically, 66% of the lesions were of the cystic variant and 34% of the solid (neoplastic) variant. The terminology of the lesion and its histogenesis are discussed.