한국인 턱끝구멍의 형태

Abstract

When implantation or genioplasy and orthogenathic surgery being performed on patients, the position of the anterior limit of the mandibular canal and the geometrical relation between the mental foramen and the mandibular canal should be considered on the basis of clinical and anatomical aspects. In an attempt to analyze the mental canal and foramen in mandibles and the internal structure of the mandibles, ninety-three adult Korean mandibles were radiographer and fifty-two hemisected mandibles were sectioned to observe the mental foramen and the internal structure of the mandible on image analyzer. In dry mandibles, the prevalence in which the mental foramen was located beneath the mandibular second premolar was the most commonly seen one(92.0%). Among them, the prevalence in which the mental foramen located beneath the center of the mandibular second premolar, mesial of the mandibular second premolar and distal of the mandibular second premolar were 47.0%, 18.0% and 27.0%, respectively. The radiographic appearances of the mandibular canal and mental foramen were classified into four types : A continuous type which showed continuity with the mental foramen through the mandibular canal, a separated type in which the mental foramen was distinctly separated from the mandibular canal, a diffused type in which the mental foramen with indistinct border and an unidentified type in which the mental foramen could not be identified on the radiographs. These prevalences in order were 28.3%, 21.7%, 22.4% and 27.6%, respectively. On sectioned specimens, the region where the mandibular canal leads to the mental foramen was formed 'cavity' and the distance between the inferior margin of the mental foramen and the inferior margin of the mandibular canal was 2.4±0.7 mm. Taken all together, in most of the cases, the anterior border of the mandibular canal is located around the premolar region, and the mental foramen is opened nearly the second premolar. Therefore, it may be suggested that osteotomy has to be taken at the anterior place next to the canine region, at the 2.4mm below to the mental foramen on genioplasty.