The Value of 3-Dimensional Computed Tomography for Jaws Osteotomies

抄録

Three dimensional computed tomography (3D-CT) has been used widely in diagnosis and treatment for patients with jaw deformity. In present study, the author assessed the value of 3D-CT in jaw osteotomies. Anatomic measurement data from 3D-CT was used to guide surgical treatment. 42 patients with dentofacial deformity (28 females and 14 males) were selected as study group who underwent Le Fort I osteotomy with bilateral sagittal split ramus osteotomy or intraoral vertical ramus osteotomy (IVRO). The patients in study group were observed on 3D-CT acquired with a slice thickness of 1.25mm between June 2006 and June 2010. 20 patients were selected as control group who underwent the same osteotomy between June 2006 and June 2010. Patients in control group underwent X-rays such as panoramic film and cephalometric radiography, but no anatomic measurements. The following anatomical data was measured for study group: 1. the distance from lingula mandibulae to anterior border of ramus, posterior border of ramus and inferior border of simoid notch; 2. the width between the outer mandibular canal and buccal side cortical bone at three location planes: the mandibular foramen plane (MFP), the mandibular angle plane (MAP) and the intermediate plane (MIP) between MFP and MAP; 3. the height of bilateral pterygomaxillary junction; 4. the anteroposterior distance from bilateral anterior nasal aperture to canalis pterygopalatinus. According to the anatomical data from 3D-CT, surgeons can take measures to avoid some complications during operation. As for study group, 42 patients satisfied with operation didn’t experience severe complications such as avascular necrosis, unexpected fracture and haemorrhage and so on. As for control group, 3 patients suffered from mandible fracture and 1 patient descending palatine artery blooding. All the results showed that 3D-CT was valuable for jaws osteotomies.