The Oropharyngeal Airway in Young Adults with Skeletal Class II and Class III Deformities: A 3-D Morphometric Analysis

Objectives 1) To determine the accuracy and reliability of an automated anthropometric measurement software for the oropharyngeal airway and 2) To compare the anthropometric dimensions of the oropharyngeal airway in skeletal class II and III deformity patients. Methods Cone-beam CT (CBCT) scans of 62 patients with skeletal class II or III deformities were used for this study. Volumetric, linear and surface area measurements retroglossal (RG) and retropalatal (RP) compartments of the oropharyngeal airway was measured with the 3dMDVultus software. Accuracy of automated anthropometric pharyngeal airway measurements was assessed using an airway phantom. Results The software was found to be reasonably accurate for measuring dimensions of air passages. The total oropharyngeal volume was significantly greater in the skeletal class III deformity group (16.7 ± 9.04 mm3) compared with class II subjects (11.87 ± 4.01 mm3). The average surface area of both the RG and RP compartments were significantly larger in the class III deformity group. The most constricted area in the RG and RP airway was significantly larger in individuals with skeletal class III deformity. The anterior-posterior (AP) length of this constriction was significantly greater in skeletal class III individuals in both compartments, whereas the width of the constriction was not significantly different between the two groups in both compartments. The RP compartment was larger but less uniform than the RG compartment in both skeletal deformities. Conclusion Significant differences were observed in morphological characteristics of the oropharyngeal airway in individuals with skeletal class II and III deformities. This information may be valuable for surgeons in orthognathic treatment planning, especially for mandibular setback surgery that might compromise the oropharyngeal patency.published_or_final_versio

The Evolution of Dental Journals from 2003 to 2012: A Bibliometric Analysis

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How accurate are the fusion of Cone-beam CT and 3-D stereophotographic images?

Background: Cone-beam Computed Tomography (CBCT) and stereophotography are two of the latest imaging modalities available for three-dimensional (3-D) visualization of craniofacial structures. However, CBCT provides only limited information on surface texture. This can be overcome by combining the bone images derived from CBCT with 3-D photographs. The objectives of this study were 1) to evaluate the feasibility of integrating 3-D Photos and CBCT images 2) to assess degree of error that may occur during the above processes and 3) to identify facial regions that would be most appropriate for 3-D image registration. Methodology: CBCT scans and stereophotographic images from 29 patients were used for this study. Two 3-D images corresponding to the skin and bone were extracted from the CBCT data. The 3-D photo was superimposed on the CBCT skin image using relatively immobile areas of the face as a reference. 3-D colour maps were used to assess the accuracy of superimposition were distance differences between the CBCT and 3-D photo were recorded as the signed average and the Root Mean Square (RMS) error. Principal Findings: The signed average and RMS of the distance differences between the registered surfaces were -0.018 (±0.129) mm and 0.739 (±0.239) mm respectively. The most errors were found in areas surrounding the lips and the eyes, while minimal errors were noted in the forehead, root of the nose and zygoma. Conclusions: CBCT and 3-D photographic data can be successfully fused with minimal errors. When compared to RMS, the signed average was found to under-represent the registration error. The virtual 3-D composite craniofacial models permit concurrent assessment of bone and soft tissues during diagnosis and treatment planning. © 2012 Jayaratne et al.published_or_final_versio

Normative Findings for Periocular Anthropometric Measurements among Chinese Young Adults in Hong Kong

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How does mandibular advancement with or without maxillary procedures affect pharyngeal airways? An overview of systematic reviews

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Oral cavity cancer trends over the past 25 years in Hong Kong: a multidirectional statistical analysis

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Are neoclassical canons valid for southern chinese faces?

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Three-dimensional photogrammetry for surgical planning of tissue expansion in hemifacial microsomia

Background: We aim to illustrate the applications of 3-dimensional (3-D) photogrammetry for surgical planning and longitudinal assessment of the volumetric changes in hemifacial microsomia. Methods. A 3-D photogrammetric system was employed for planning soft tissue expansion and transplantation of a vascularized scapular flap for a patient with hemifacial microsomia. The facial deficiency was calculated by superimposing a mirror of the normal side on the preoperative image. Postsurgical volumetric changes were monitored by serial superimposition of 3-D images. Results. A total of 31 cm3 of tissue expansion was achieved within a period of 4 weeks. A scapular free flap measuring 8 cm × 5 cm was transplanted to augment the facial deficiency. Postsurgical shrinkage of the flap was observed mainly in the first 3 months and it was minimal thereafter. Conclusion. 3-D photogrammetry can be used as a noninvasive objective tool for assessing facial deformity, planning, and postoperative follow-up of surgical correction of facial asymmetry. © 2009 Wiley Periodicals, Inc.postprin

3-D facial anthropometric norms for the southern Chinese

Session 9 - Integration of Innovations in Teaching and Daily RoutinePURPOSE: Accurate and demographic-specific normative data are required for the precise quantification of dysmorphology when accessing facial deformities. However, normative three-dimensional (3-D) data are not currently available for Chinese faces. The aims of this study were; (1) to create a normative database of facial anthropometric measurements for young adults with southern Chinese ancestry, (2) to develop a 3-D anthropometric analysis scheme applicable for assessing dentofacial deformities and (3) to compare the facial anthropometric measurements of young Chinese males and females …postprin

Effect of Ovariectomy on Stimulating Intracortical Remodeling in Rats

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