[Clinical and imaging features of 36 odontogenic keratocysts associated with an impacted tooth].

ABSTRACT

PURPOSE: To analyse the imaging features of odontogenic keratocysts (OKCs) associated with an impacted tooth. METHODS: Clinical and radiological data of 235 cases with OKCs were respectively investigated, with emphasis on imaging features of 36 OKCs, which were associated with an unerupted tooth. RESULTS: In 36 cases of OKCs associated with an impacted tooth, the ratio of male to female was 1.771, and molar-ramus was involved in 26 cases (72.22％). OKCs in association with an unerupted tooth occurred mostly in patients ranging from 20 to 30 years (19 cases, 52.8％). There were 27 cases (75％) of unilocular and 9 cases (25％) multilocualr radiolucency. Thirteen cases (36.11%) were related to the crown of the impacted teeth, and the unerupted teeth also were impacted as a result of malposition in which the entire teeth appeared to be enveloped by cysts (15 cases, 41.67%), or adjacent to cyst wall (8 cases, 22.22%). CONCLUSIONS: Radiographically, one of the most imaging features of OKCs in association with an unerupted tooth is that its entire tooth appears to be enveloped by cyst or adjacent to cyst, while pericoronal radiolucencies surrounding an impacted tooth are rarely seen.