Study of bone remodeling incidental to orthodontic tooth movement.

Research Project

Project/Area Number	05671727
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	矯正・小児・社会系歯学
Research Institution	Tsurumi University
Principal Investigator	KAIDA Kiyokazu Tsurumi University, School of Dental Medicine, Assistant Professor, 歯学部, 講師 (50139606)
Co-Investigator(Kenkyū-buntansha)	HIRASHITA Ayao Tsurumi University, School of Dental Medicine, Associate Professor, 歯学部, 助教授 (70089457) KAWAMOTO Tadafumi Tsurumi University, School of Dental Medicine, Assistant, 歯学部, 助手 (60148046) SHIMIZU Masaharu Tsurumi University, School of Dental Medicine, Professor, 歯学部, 教授 (40064357) 甲斐哲也鶴見大学, 歯学部, 助手 (80169375)
Project Period (FY)	1993 – 1995
Project Status	Completed (Fiscal Year 1995)
Budget Amount *help	¥2,200,000 (Direct Cost: ¥2,200,000) Fiscal Year 1995: ¥500,000 (Direct Cost: ¥500,000) Fiscal Year 1994: ¥700,000 (Direct Cost: ¥700,000) Fiscal Year 1993: ¥1,000,000 (Direct Cost: ¥1,000,000)
Keywords	tooth movement / tension side / adult Wistar rats / serum BGP / bone formation / osteoblast / the osteoid / the bundles of collagen fibers / 牽引側 / 血清アルカリホスファターゼ / 新生骨 / 骨形成機序
Research Abstract	The mechanizm of bone remodeling incidental to orthodontic tooth movement was studied experimentally in rat) and clinically in adult women. 1.The histological study : The upper first molars in adult Wistar rats were moved in the lingual direction by wire springs with about 10g for 1,3,5,7,9,14,21 days. The following results were obtained ; 1) Two types of bone apposition were seen on the collagen fibrils and along the bundles of collagen fibers. 2) mineral deposits on the bundles of collagen fibers seemed to grow more than on the collagen fibrils in the osteoid. 3) Immunolocalization of BGP was observed on the bone surfaces of tension side in the periodontium. The results suggest that bone apposition on the tension side occurred not only on the collagen fibrils in the osteoid, but also on the collagen fibers in the region of bone surfaces. 2.The Serum biochemical study in rats : Serum BGP of 12 week-old rats showed a significant decrease in the 3 days' group versus the control group. Judging from these results, the decrease in the 3 days and the increase the 5-21 days of serum BGP may reflect bone turnover in the periodontium. 3.The Serum biochemical study in orthodontic patients : Serum BGP were measured in 10 adult woomens (19y3m-26y1m) treated with multi-bracket appliances. The 1st measurements were before treatment, the 2nd were after the tooth extraction, the 3rd were after canine retraction. Serum BGP at the each three measurements changed significantly (Mean (]SY.+-.]) S.D. : before treatment 9.36 (]SY.+-.]) 4.08ng/ml, after extraction 17.9 (]SY.+-.]) 4.24ng/ml, after canine retraction 9.37 (]SY.+-.]) 3.59ng/ml : F=5.22, p<0.05, by ANOVA). It is suggested that the changes in serum BGP may reflect bone turnover in the periodontium caused by tooth extraction and canine retraction.