Symptomatic residual radicular cysts.

The clinical, radiological and histological characteristics of 31 symptomatic residual radicular cysts are compared and contrasted with 39 asymptomatic residual cysts. Differences in size and site incidence are demonstrated along with an inversely proportional relationship between radiographic cortication and degree of acute inflammation in the cyst wall. A number of possible aetiological factors, to account for initiation of active inflammation in deeply placed residual cysts have been examined and excluded, but explanation, in most cases, remains paradoxical.