Abstract
The mandibular third molars are usually located near the inferior alveolar nerve, and surgical extraction may damage this nerve causing dysesthesia. Recently, cone-beam computed tomography (CBCT) has become more widespread, facilitating the diagnosis of various diseases of the oral maxillofacial region. This study investigated dysesthesia of the inferior alveolar nerve following mandibular third molar extraction and the relationship between this complication and preoperative imaging findings. A total of 401 mandibular third molars were extracted from 345 patients with a mean age 33.9 ± 14.6 years (range, 16-81 years). All patients were evaluated by panoramic radiography, and 89 mandibular third molars were evaluated by CBCT. We classified the shape of the mandibular canal into 4 types based on its shape at the point closest to the mandibular third molars. The rate of dysesthesia after mandibular third molar extraction was 5.7% among patients considered to be at high risk who underwent CBCT, and 0.64% among patients considered to be at low risk. The mandibular third molars were not in contact with the inferior alveolar nerve in 51 of the patients who underwent CBCT. These results suggest that deformation of the mandibular canal may lead to dysesthesia following mandibular third molar extraction and that CBCT was useful for predicting the risk of this complication.
