Abstract
Application of computed tomography(CT) has significantly improved the precision of the preoperative examination for dental implant treatment.This can contribute to the successful implantation procedure with safe and less anxiety in the treatments.However,the complications such as serious hemorrhage and nerve injury may occur when the implants are carried in the mandible if the accurate information on morphologies of bone cross-section and route of mandibular canal is not obtained.The studies on the route of mandibular canal using cadavers or the morphological studies on cross-sections of mandibular bones using CT were reported previously,but,as far as the authors' knowledge,there was no report on them using the panoramic images,cross-sectional images or three-dimensional(3D) images obtained by CT.The purpose of this study was to examine the efficacy of CT images on the morphologies of crosssection and the route of mandibular canal near mental foramen in mandible.A total of 105 human subjects was investigated using dental CT( New Tom).The gourd-shaped (or hourglass-shaped) cross-sectional bone image was found in 30.5% of the crosssectional images near mental foramen obtained by CT.The panoramic images and 3D images exhibited that the average length and the maximal length of mandibular incisive canal were respectively 8mm and 21mm in this study.The study suggests that CT examination should be essential in preoperative examination and more precise and accurate treatment planning could be achieved by diagnosis using CT.
