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Anterior maxillary osteotomies are performed to correct sagittal and vertical discrepancies in the maxilla.

This case report describes the successful orthodontic treatment of a 12-year-old girl with skeletal Class III malocclusion and severe root resorption of the maxillary anterior teeth. Ectopic eruption and mesial inclination of the bilateral maxillary canines caused severe root resorption of the right central and lateral incisors and the left lateral incisor. These 3 teeth were extracted, and traction was applied to the maxillary right and left canines toward the extracted right central incisor and left lateral incisor, respectively. In the mandibular arch, the bilateral first premolars were extracted, and the crowding was corrected. The extracted mandibular right first premolar was transplanted after extraction of the maxillary right lateral incisor. To prepare for the tooth transplantation, a cone-beam computed tomography image was used to fabricate a 3-dimensional printed replica of the donor tooth. The crown shape of the maxillary anterior teeth was corrected, and the patient achieved functional occlusion with pleasing esthetics. Root resorption was negligible in the transplanted tooth. This study demonstrates the satisfactory treatment outcome and an effective 3-dimensional simulation for tooth transplantation.

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BackgroundThe precise characteristics of posterior cranial vault deformation are difficult to identify using a two-dimensional analysis. Recently, three-dimensional analysis using computed tomography (CT) data and software analysis has enabled us to examine the craniofacial structure precisely. To identify the deformation in the cranial vaults by a three-dimensional analysis and examine its effects on other structures, CT data of skeletal mandibular protrusion cases without lateral deviation of pogonion (Pog) were examined.MethodsThirty-two adult female patients with skeletal mandibular protrusion who visited Meikai University Hospital were included in this study. CT images were taken before orthognathic surgeries, and the craniofacial structures were examined threedimensionally.The lateral deviation of Pog was less than 3 mm in all cases.Genetic/congenital anomaly cases, endocrine disorders, or cases with severe trauma or temporomandibular disorder were excluded.ResultsMany cases had three-dimensional deformations in the cranial vaults. The cranial vaults with unilateral posterior deformation had posteriorly positioned mandibular fossae on the same sides. Mandibular body lengths were related to the position of the mandibular fossae, and the posterior mandibular fossae tended to have longer mandibular body lengths on the same sides. Masseter muscles with larger volumes were related to longer mandibular body lengths.ConclusionsMandibular body lengths can compensate for the bilateral difference in the position of the mandibular fossae to avoid lateral deviation of the Pog. The masseter muscles are likely one of the factors related to the bilateral differences in the mandibular body length.