Grant-in-Aid for General Scientific Research (C)
|Allocation Type||Single-year Grants|
|Research Institution||HOKKAIDO UNIVERSITY|
TAKAHASHI Naoyuki(1995) HOKKAIDO Univ., School of Dentistry, Inst., 歯学部, 助手 (40261317)
友近 晃(1994) 北海道大学, 歯学部, 助手 (20241341)
山村 雅彦(1993-1994) 北海道大学, 歯学部, 助手 (90220441)
松野 功(1993) 北海道大学, 歯学, 助手
ANDOH Yohsuke HOKKAIDO Univ., Dental Hospital, Inst., 歯学部附属病院, 助手 (10271686)
YAMAMOTO Takaaki HOKKAIDO Univ., Dental Hospital, Lec, 歯学部附属病院, 講師 (40230560)
ISHIKAWA Hiroyuki HOKKAIDO Univ., Dental Hospital, Lec, 歯学部附属病院, 講師 (20184492)
IMAI Thoru HOKKAIDO Univ., School of Dentistry, Assoc. Pro., 歯学部, 助教授 (40160030)
NAKAMURA Shinji HOKKAIDO Univ., School of Dentistry, Inst., 歯学部, 教授 (80001791)
高橋 直行 北海道大学, 歯学部附属病院, 助手 (40261317)
友近 晃 北海道大学, 歯学部・附属病院, 助手 (20241341)
|Project Period (FY)
1993 – 1995
Completed(Fiscal Year 1995)
|Budget Amount *help
¥2,100,000 (Direct Cost : ¥2,100,000)
Fiscal Year 1995 : ¥400,000 (Direct Cost : ¥400,000)
Fiscal Year 1994 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1993 : ¥1,200,000 (Direct Cost : ¥1,200,000)
|Keywords||3D CT / Facial Asymmetry / Mandibular Morphology / Cleft lip and palate / Masseter muscle activity / 9 channel EMG analyzing system / Asymmetry Index / Occlusal stability undex / 3DCT / Facial Asymmetry / Mandibular Morphology / 多チャンネル筋電図分析システム / EMG / 咬筋筋活動パターン|
The purpose of the present study is to analyze morphologically with the three-dimensional reconstruction of CT images and to investigate functionally with the 9 channel EMG analyzing system.
22 mandibular landmarks were used from the 3D CT image tomeasure 12 bilateral linear, angular, and area items.
From these bilateral measurement items, we established averages, differences between the left and right sides of the mandible, the percentage of difference in relation to the average, the degree of asymmetry, and an index of degree of asymmetry. the Asymmetry Index. With this index morphological asymmetries in the hemifacial microsomia patients were found in more locations and of a higher degree than in patients with other skeletal deformities.
The relationship between the muscle activity of the masseter muscle at maximum voluntary clenching and the occlusal stability were studied in cleft lip and palate patients and normal subjects, both in children and adults. The masseter muscle activity (amount and symmetry) was investigated with 9 channel EMG analyzing system.
The child Non-constricted Arch Group (NCG) showed almost the same muscle activity and Occlusal Stability Index (OSI) as that of normal child subjects. However, the child Constricted Arch Group (CG) showed both poor and asymmetric muscle activity and occlusal stability. A strong relationship between the masseter muscle activity and OSI was recognized. After wearing an occlusal splint for 10days, the masseter muscle activity of the child CG was observed to improve and became well balanced, bilaterally with increased occlusal force. In comparing child groups with adult groups, the NCG and the normal subjects showed very similar rates of increase in the amount of muscle activity and OSI,the CG showed remarkable rates of increase, above those of normal subjects and the NCG.These increases in the CG may result from the effect of orthodontic treatment as well as normal development.