Incidence of cystic changes in radiographically normal impacted lower third molar follicles

The objective of this study was to investigate the cystic changes in radiographically normal follicles associated with impacted lower third molars (ILTM). The relation between the cystic changes and both the angular position and the contact of ILTM with the adjacent tooth was also evaluated.

Follicular spaces of patients who were referred to our clinic for removal of ILTM for a variety of reasons were measured from panoramic radiographs by each author independently. Pericoronal tissues of radiographically normal impacted third molars were examined histopathologically. Then the data were analyzed for associations with age, sex, angular position, and contact of the ILTM with the second molar.

There were 30 male and 64 female patients, ages ranging from 14 to 45 years (mean = 21.11). Forty-seven (50%) of the 94 specimens showed cystic changes as the only pathological condition other than inflammation. Most of the cystic changes occurred in the 20-25 year age range. The relation between cystic changes and angular position was statistically significant (chi 2 = 7.46, P < .05). The higher probability of cystic changes was found in the vertically positioned ILTM. The relation between the cystic changes and communication of ILTM with the second molar was not statistically significant (chi 2 = 2.068, P > .05).

Cystic changes may be encountered in the histopathologic examination of asymptomatic third molars, especially in patients older than 20 years. Vertically positioned ILTM especially may be suspected for the higher possibility of cystic changes.