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This paper reviews the role of three-dimensional digital imaging in dentistry and its related specialties. Current methods of image capture of the dentition are described, along with the current status of CAD/CAM-based restorative treatment. The advantages of cone beam computed tomography (CBCT) in comparison with conventional radiography are outlined in the fields of endodontics, periodontology, oral surgery and orthodontics. The integration of CBCT with state-of-the-art computer planning systems for implantology is described. The application of multi-modal imaging techniques in the management of orthognathic and cleft lip and palate patients is explained and potential future educational benefits are considered. Clinical Relevance: With three-dimensional digital imaging and its related technologies advancing rapidly, it is important for both general and specialist dental practitioners to have an awareness of its current and potential future roles in clinical practice. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To investigate a registration approach for 2-dimension (2D) based on characteristic localization to achieve 3-dimension (3D) fusion from images of PET, CT and MR one by one. Method: A cubic oriented scheme of“9-point & 3-plane” for co-registration design was verified to be geometrically practical. After acquisiting DICOM data of PET/CT/MR (directed by radiotracer 18F-FDG etc.), through 3D reconstruction and virtual dissection, human internal feature points were sorted to combine with preselected external feature points for matching process. By following the procedure of feature extraction and image mapping, “picking points to form planes” and “picking planes for segmentation” were executed. Eventually, image fusion was implemented at real-time workstation mimics based on auto-fuse techniques so called “information exchange” and “signal overlay”. Result: The 2D and 3D images fused across modalities of [CT+MR], [PET+MR], [PET+CT] and [PET+CT+MR] were tested on data of patients suffered from tumors. Complementary 2D/3D images simultaneously presenting metabolic activities and anatomic structures were created with detectable-rate of 70%, 56%, 54% (or 98%) and 44% with no significant difference for each in statistics. Conclusion: Currently, based on the condition that there is no complete hybrid detector integrated of triple-module [PET+CT+MR] internationally, this sort of multiple modality fusion is doubtlessly an essential complement for the existing function of single modality imaging. [Copyright &y& Elsevier]

After orthognathic surgery the forehead remains unchanged. To produce facial harmony, the planned projection of the maxillomandibular complex must be placed in the correct relations to the unchanged position of the forehead. We have compared the anterior soft tissue projection of the maxillomandibular complex relative to the forehead after Le Fort I advancement surgery for correction of maxillary hypoplasia with that of a local reference group chosen by lay assessors. We retrospectively studied 32 patients (16 men and 16 women) all of whom had previously been treated by Le Fort I maxillary advancement. In addition a panel of 8 lay assessors selected a reference group of 24 women and 16 men. Standard profile photographs were taken, and horizontal measurements made, of several landmarks from a true vertical line (TV) passing through glabella. Together with facial harmony values these were compared between the groups. The orthognathic group had significantly more anterior mandibular projection relative to the forehead than the female reference group (p=0.03). As a result half of the horizontal harmony values were smaller in the orthognathic group. For men the position of the mandible, particularly the chin, was acceptable even though it was positioned more anteriorly. We have provided values for maxillomandibular projection derived from lay assessors and identified areas where differences from those of a reference group were detected. The projection of the mid and lower face of the local reference group to the forehead should guide preoperative planning., (Copyright © 2014 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Background and Aims: Because there is no complete three-dimensional (3D) hybrid detector integrated PET+MRI internationally, this study aims to investigate a registration approach for a two-dimensional (2D) hybrid based on characteristic localization to achieve a 3D fusion from the images of PET and MRI as a whole., Methods: A cubic-oriented scheme of "9-point and 3-plane" for a coregistration design was verified to be geometrically practical. Through 3D reconstruction and virtual dissection, human internal feature points were sorted to combine with preselected external feature points for matching process. By following the procedure of feature extraction and image mapping, the processes of "picking points to form planes" and "picking planes for segmentation" were executed. Eventually, the image fusion was implemented at the real-time workstation Mimics based on auto-fuse techniques called "information exchange" and "signal overlay"., Results: A complementary 3D image across PET+MRI modalities, which simultaneously present metabolic activities and anatomic structures, was created with a detectable rate of 56%. This is equivalent to the detectable rate of PET+CT or MRI+CT with no statistically significant difference, and it facilitates a 3D vision that is not yet functional for 2D hybrid imaging., Conclusions: This cross-modality fusion is doubtless an essential complement for the existing toolkit of a 2D hybrid device. Thus, it would potentially improve the efficiency of diagnosis and therapy for oncology.

Unlabelled: This paper reviews the role of three-dimensional digital imaging in dentistry and its related specialties. Current methods of image capture of the dentition are described, along with the current status of CAD/CAM-based restorative treatment. The advantages of cone beam computed tomography (CBCT) in comparison with conventional radiography are outlined in the fields of endodontics, periodontology, oral surgery and orthodontics. The integration of CBCT with state-of-the-art computer planning systems for implantology is described. The application of multi-modal imaging techniques in the management of orthognathic and cleft lip and palate patients is explained and potential future educational benefits are considered., Clinical Relevance: With three-dimensional digital imaging and its related technologies advancing rapidly, it is important for both general and specialist dental practitioners to have an awareness of its current and potential future roles in clinical practice.