The paradental cyst: a clinicopathologic study of 50 cases

The paradental cyst is an odontogenic cyst of inflammatory origin, which occurs on either the buccal, distal, or (rarely) mesial aspects of partially erupted mandibular third molars. In most cases there is an associated history of recurrent pericoronitis. The clinicopathologic features of 50 cases are reviewed. The frequency of the paradental cyst is 3% to 5% of all odontogenic cysts, although we believe its true incidence to be higher. All cases occur in the mandible, and there is a marked preponderance in males. White persons are affected more frequently than blacks. The size of the cysts varies from 1 to 2 cm; they are attached to the cementoenamel junction (CEJ) and the coronal third of the roots. Histologically, they cannot be distinguished from other inflammatory odontogenic cysts. While origin from junctional epithelium or cell rests of Malassez cannot be entirely excluded, we favor an origin from reduced enamel epithelium and suggest that cyst formation occurs as a result of unilateral expansion of the dental follicle secondary to inflammatory destruction of bone and periodontium.