Establishment of Systems based on Biomechanical Analysis for Cleft Palate Treatment

1998 Fiscal Year Final Research Report Summary

• Project/Area Number: 09470475
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 矯正・小児・社会系歯学
• Research Institution: Showa University
• Principal Investigator: SHIBASAKI Yoshinobu School of Dentistry, Professor, 歯学部, 教授 (40014005)
• Co-Investigator(Kenkyū-buntansha): HIRAKAWA Takashi School of Dentistry, Assistant, 歯学部, 助手 (20266175) ; MIKAWA Masatoshi School of Dentistry, Assistant, 歯学部, 助手 (20276603) ; MAKI Koutarou School of Dentistry, Lecturer, 歯学部, 講師 (80219295)
• Project Period (FY): 1997 – 1998
• Keywords: Cleft Lip Palate / Finite Element Analysis / Computed Tomographic / Ultrasonic Diagnostic Analysis / Biomechanics

Research Abstract

In cleft palate patients, it is well recognized that their dento-maxillo facial skeletons and masticatory systems demonstrate severe deformity and malfunctions. Complexity and difficulty of orthodontic treatment was caused on these morphological and functional characteristics. For further understanding of treatment effectiveness and establishment of considerable procedure, we need a biomechanical analysis of our treatment. Iii addition, evaluating bone mineralization of the maxilla has important clinical implications. Moving teeth orthodontically and/or expansion of dental arch depended upon the level of bone mineralization within the alveolar bone. In this study, we proposed some methods which integrate morphological measurement, functional evaluation and mechanical analysis. New computational software programs were developed. Individual digital data derived from CT scanning and measurement of cast model were used for analysis. Patient specific Finite Element Model was constructed from CT data. Mechanical properties (i.e., Young's modulus) were evaluated using x-ray attenuation value (i.e., GT number), structural properties were adjusted by coordinate transformation method. Bone density distribution and biomechanical behavior under palatal expansion and chin cap therapy were determined by our new system. The results showed that the normal subjects had a bilaterally symmetrical distribution of regions with high shear stress. However in cleft palate patient, altered bone density distribution and displacement by expansion depend on density value were found. These computer-assisted programs can be used to derive clinically useful information in individual subjects.