The findings yielded by this study confirm that S, αS, and αZ are reliable and reproducible. None of the 28 patients complained about postoperative asymmetry or had any requests regarding esthetic modifications. This allowed plotting the symmetry axis of facial bones, passing through the middle of the clivus c, which served as the reference origin (Fig. 1). Axial cut across the infraorbital foramen, allowing the entire zygoma complex to be visible, was selected. All tomographic images were repositioned on the orbito-meatal plane and refocused in the spatial planes. The radiological study described here was performed with the help of Osirix Lite ® software for Macintosh ®, Version 6.5.1 (April 2015). The clinical relevance of this approach is evaluated on postoperative tomographic examination with the zygoma symmetry reduction as the main success criterion. In order to optimize and simplify intraoperative tomographic control by CBCT or virtual planning, as well as postoperative CT and CBCT control, referential measures are placed on a precisely chosen single axial cut.īased on the above information, the aim of our study was to propose and to evaluate the reliability and reproducibility of 3 referential measures, taking into account the morphology, the summit, and the symmetry of the zygoma obtained from CT examination. The elaboration of osteomorphometric tomographic referential measures on computed tomography (CT) and cone beam computed tomography (CBCT) on a single axial cut, considering the maximum of the anterolateral projection of the zygoma, could have important applications in the peroperative and postoperative radiological control of fractures. In extant research, it has been used as a reference in tomographic studies of facial bone symmetry (Furst et al., 2001, Gong et al., 2014). The summit of the zygoma corresponds to the maximum of the anterolateral dimension, and has been described by different authors (Gola et al., 2006, Nagasao et al., 2011). The global criteria attesting to the quality of the reduction focus on symmetry recovery compared to the healthy side of the patient's face.įacial bones are relatively and physiologically symmetric, with up to 2.5-mm differences deemed acceptable (Farkas, 1981). The recovery of the projection, in terms of the height and the width of the cheekbone, is 1 of the main challenges in traumatized zygomatic complex surgeries. Kristensen and Tveterås, 1986, Czerwinski et al., 2005). The reasons for the resulting postoperative complications are varied and include oculomotricity problems, compromised vision, modification of the orbital volume, neurological deficit of the infraorbital nerve, and zygomatic asymmetry in particular (e.g. Ellis and Kittidumkerng, 1996, Zachariades et al., 1998 e.g. The currently used treatments have evolved as a result of technological advances, which allowed available surgical techniques to benefit from the integration of peroperative imaging (Zingg et al., 1991, Zingg et al., 1992, Rohrich et al., 1992 e.g. Bogusiak and Arkuszewski, 2010, Boffano et al., 2015) and can lead to significant functional losses and esthetic issues due to their important anatomic location. Some researchers have evaluated bone characteristics in different regions of the maxilla, mandible, and alveolar bone in order to identify the best places for miniscrew insertion.Zygoma fractures are relatively frequent (e.g. 7, 8 The most preferred sites for their placement are the interradicular vestibular alveolar zone, hard palate, and infrazygomatic crest and in the mandible, these regions include mandibular triangle, retromolar area, and mandibular buccal shelf (MBS). 1, 9 - 11 In cases requiring retraction of the lower teeth, MBS is the best area for miniscrew insertion in the extra-alveolar bone of the posterior zone of the mandible. ![]() ![]() ![]() 12, 13 MBS is bilaterally located buccal to the roots of the first and second mandibular molars and anterior to the oblique line of the mandibular ramus, and it provides adequate quantity and quality of bone for miniscrew insertion. 13 However, variations in the depth and thickness of the bone along its course may affect miniscrew placement. Therefore, the purpose of this study was to evaluate MBS in terms of the angulation and bone depth and thickness according to sex, age, sagittal skeletal pattern (SSP), and vertical skeletal pattern (VSP) using cone-beam computed tomography (CBCT) images in a Colombian population. Accordingly, we explored the optimal site for miniscrew insertion in this area. This descriptive, retrospective study included digital lateral cephalograms (DLCs) and CBCT records of 88 patients recruited from different private practices in the cities of Cartagena (n = 10), Medellín (n = 39), and Pereira (n = 39) in the country of Colombia. For all eligible patients, CBCT images were obtained as part of their initial records.
0 Comments
Leave a Reply. |