Evaluation of Normal Anatomy of the Mandible Using Three Dimensions Computed Tomography and Orthopantomography

Abstract

The three-dimensional (3D) multi planar reformatted images from conventional cross-sectional computed tomography data have been increasingly used to better demonstrate the anatomy and pathologic conditions of various organ systems. This study was conducted to assess the 3D CT and OPG techniques in demonstrating the anatomy of the mandible including body, ramus, symphysis menti and TMJ, lamina Dura, pulp canal, root of the teeth, mandibular canal, mandibular angle. Samples of twenty Sudanese adult male patients of ages between (20-60years) who were clinically diagnosed as normal, without any fractures, infection, caries, periodontal disease, per apical Pathology, or affected by any bone diseases, were included in this study. 3D facial bone was done for ten of the sample and OPG was done for the other ten. This study was done in Modern Medical Center and Mursi Medical Dental Center in the period from May to August 2010. The machines used were general electric CT/with dual slice (Germany) with: Voltage: 120KV, 140KV, Current four options 60 mA, 80 mA, 100 mA and 160 mA. The orthopantomograph, model OP 5 (Siemens Bens-him, Germany), with the setting were selected typically in the range 70-100 KV and 4-12 mA. The results of this study showed that the OPG technique was the best in demonstrating the root of the teeth (45%), TMJ(10%), Ramus (15%), Lamina Dura (5%), where the 3D CT was the best in demonstrating mandibular angle, and body of the mandible, ramus, smphysis menti for (95%), respectively, and TMJ for (70%). Both techniques failed to demonstrate pulp canal, and mandibular canal, (0%).