Clinical evaluation of facial changes in patients treated with rapid maxillary expansion in mixed and permanent dentition

Modern orthodontics takes into account and analyzes not only changes in the tooth position and occlusion, but also changes in the soft tissues of the face. To accurately assess these changes during orthodontic treatment, models obtained from 3D facial scans are used. Facial scanners and CBCT examinations provide the ability to capture and assess three-dimensional changes in the soft tissues. This study describes the difference after orthodontic treatment in automatically generated 3D models of the face using CBCT examination. The aim is to localize the areas of change in facial structures during patient treatment. Two patients with transverse maxillary deficiency were selected – one in mixed dentition and the other in permanent dentition. The deficiency is associated with unilateral (in mixed dentition) and bilateral (in permanent dentition) distal crossbite. The patients were treated with a metal-printed appliance for tooth-borne rapid maxillary expansion. 3D bone and facial images were obtained from a CBCT examination performed in the diagnostic phase (T1) and at the end of the retention phase and immediate removal of the appliance (T2). The period between T1 and T2 was 4–5 months. Bone changes in the transverse direction are assessed and superimposition of bone and soft tissue structures is performed. An increase in the width of the maxillary base, hard palate, alveolar bone dimensions, and occlusal width is achieved. No changes in the alveolar width of the mandible was observed, but clinically, its spontaneous rotation and displacement is observed after deblocking the occlusion. The most significant change in the soft tissues is found in the nasal width, the subnasal area, the upper lip, and the area of the zygomaticomaxillary suture. Modern technologies offer various systems (software) for facial imaging. The data obtained outlines the areas of change that would be target fields when searching for discrepancies using facial imaging.

Dr Emanuel Emiliyanov

Department of Orthodontics

Faculty of Dental medicine

Medical University – Sofia

1,“St. Georgi Sofiiski” Blvd.

Sofia 1431, Bulgaria

e-mail: emanuelemilianov@gmail.com

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