Evaluation of mandibular volume using cone-beam computed tomography and correlation with cephalometric values

Abstract

Objective: To investigate the association between maxillofacial morphology and mandibular bone volume in patients with skeletal malocclusion. Materials and Methods: Subjects were 118 adult Japanese (58 males and 60 females). Skeletal malocclusion was classified, based on cephalometric analysis, into skeletal Classes I (21u # ANB , 4u), II (ANB $ 4u), and III (ANB , 21u). Using cone-beam computed tomography and threedimensional image analysis software, the dental crowns and mandible were separated, with only the mandible extracted. This was then reconstructed as a three-dimensional model, from which the mandibular volume was measured. Results: No significant difference in mandibular volume was noted among skeletal Classes I, II, and III, nor was there any significant correlation between mandibular volume and the ANB, SNB, or mandibular plane angles. There was occasional and limited correlation between mandible volume and gonial angle and certain cephalometric distance parameters. Conclusion: We conclude that proper understanding of the three-dimensional maxillofacial morphology requires not only cephalometric radiographic tracings but also high-resolution analysis of the mandibular area, width, and volume. (Angle Orthod. 2014;84:337-342.)

Growth hormone receptor gene variant and three-dimensional mandibular morphology

“…13,16 However, owing to the complex structure of the mandible, two-dimensional evaluation using cephalograms cannot be used for precise measurement of the mandible. 19 In the present study, we examined the association between the actual length of the mandibular bone and GHR gene variants using three-dimensional analysis. In previous reports, GHR gene SNPs (rs6180, rs6182, and rs6184) were described to be related to mandibular morphology, [13][14][15][16][17][18] with SNPs rs6182 and rs6184 in complete linkage disequilibrium.…”

“…Volume was measured following the method reported by Katayama et al 19 The mandibular bone region was segmented from the image data and analyzed using Analyze 3D reconstruction software (Biomedical Imaging Resource, Mayo Clinic and Foundation, Rochester, Minn). Mandibular volume and length were measured by autotracing the outer circumference of the cortical bone in all slides using Analyze.…”

Growth hormone receptor gene is related to root length and tooth length in human teeth

“…viewer.com) and exported using the DICOM format to a MacBook Pro personal computer (Mac OsX El Capitan 10.11.6 Apple, Cupertino, Calif). The difference in measurement between the two models of CBCT was evaluated using the method reported by Katayama et al 20 The difference was small and nonproblematic.…”

Three-dimensional Evaluation of Mandibular Volume in Patients with Cleft Lip and Palate During the Deciduous Dentition Period

“…This study examined mandibular volume and craniofacial measurements in patients with various types of clefts using CBCT and compared these measurements with noncleft control subjects who underwent CBCT for other reasons during the deciduous dentition period. Many recent studies used CBCT to evaluate mandibular volume in normal patients 15,16,18,19 as well as in patients with CLP. 6,7 Katayama et al 15 evaluated mandibular volume based on vertical and sagittal skeletal dimensions in adults and found significant correlations between mandibular volume and some parameters related to mandibular morphology.…”

“…48, and Class III, ANB , À18. 15,16 Patients were not categorized by side (left and right). All patients were nonsyndromic and had no systemic disease or history of previous orthodontic treatment.…”