Katsuhiro Minami

Development of a 3-D measurement and evaluation system for facial forms with a liquid crystal range finder

A 3-D measurement and evaluation system for facial forms was developed with a liquid crystal range finder (LCRF). Its mechanical resolution was approximately/= 0.4 mm, and it was capable of measuring >30000 points from the entire facial surface in one second. An original program was developed to identify facial landmarks using not only linear distances, but also 3D-curvatures and discriminant analysis of the RGB data. With this program, the 3-D identification of anthropometrical points became possible with high accuracy. Due to the rapidity of the measuring apparatus and morphological evaluation system, it became possible to analyze the facial forms of infants such as cleft lip patients three dimensionally, without any sedation. Therefore, 97 normal infants (mean: 4.3 months of age) were measured and analyzed with this system. A cleft lip infant was measured and compared with the normal infants before and after cleft lip surgery, and the improved points and remaining problems were clearly recognized.

Maxillary Posterior Segmental Osteotomy for Correction of Skeletal Open Bite

The treatment of skeletal anterior open bite deformity using the single-stage maxillary posterior segmental osteotomy has been followed for 5 years to evaluate the final outcome of the operation. The clinical and radiographic examination during the control period show a remarkable stable result without a relapse. Treatment planning based on clinical, ceahalometric, dental plaster model examination and tongue posture analysis allows the accurate and predictable correction of this deformity. In addition, tongue posture had shifted from anteriorly and superiorly to posteriorly and inferiorly after surgery. The stable occlusion and this improvement of tongue posture after maxillary posteriorly segmental osteotomy is an effective surgical procedure for the skeletal open bite.