Project/Area Number |
16592041
|
Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Orthodontic/Pediatric dentistry
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Research Institution | Tokyo Medical and Dental University |
Principal Investigator |
WARITA Hiroyuki Tokyo Medical and Dental University, Graduate School, Orthodontic Science, Assistant Professor, 大学院・医歯学総合研究科, 助教授 (30262207)
|
Co-Investigator(Kenkyū-buntansha) |
MATSUMOTO Yoshiro Tokyo Medical and Dental University, Dental Hospital, Orthodontics, Lecturer, 歯学部附属病院, 講師 (20292980)
KANNO Zuisei Tokyo Medical and Dental University, Graduate School, Orthodontic Science, Assistant, 大学院・医歯学総合研究科, 助手 (40345301)
KANEKO Sawa Tokyo Medical and Dental University, Graduate School, Orthodontic Science, Assistant, 大学院・医歯学総合研究科, 助手 (80372449)
HISANO Masataka Tokyo Medical and Dental University, Graduate School, Orthodontic Science, Lecturer, 大学院・医歯学総合研究科, 講師 (80282763)
TAKESHI MURAMOTO Tokyo Medical and Dental University, Graduate School, Orthodontic Science, Assistant, 大学院・医歯学総合研究科, 助手 (30345300)
|
Project Period (FY) |
2004 – 2005
|
Project Status |
Completed (Fiscal Year 2005)
|
Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2005: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 2004: ¥2,800,000 (Direct Cost: ¥2,800,000)
|
Keywords | mechanical stress / bone / periodontium / regeneration / tooth transplantation / occlusal stimuli / alveolar bone / 咬合機能低下 / 加齢 / 組織の回復再生 / 血液循環 / サーモダイナミクス |
Research Abstract |
In order to clarify the regenerative response of bone and periodontium against mechanical stress, molecular biological and histological examinations were performed. Mechanical tensional stress of low magnitude induced the increase of both type I collagen and decorin mRNA expression without changing ALP activity in periodontal ligament cells. Mechanical tensional stress of high magnitude induced the increase of type I collagen and decorin mRNA expression while decreasing ALP activity. mRNA level of Cbfa1/Runx2 increased at lower magnitudes of strain (0.8% and 5% elongation) but decreased at higher magnitude of strain (15% elongation). At 24 and 48 h, Cbfa1/Runx2 and osteocalcin mRNAs decreased at 5%, 10%, and 15% elongation, whereas cell proliferation and expression of type I collagen mRNA increased at the same elongation. the replanted teeth were given a one-week healing period and then occlusion recovery was assessed, which resulted in decreased ankylosis and root resorption. The proliferative activity of PDL cells in the occluded group was generally higher than in the nonoccluded group. The activity of PDL cells in the recovery group was also higher than that of the nonoccluded group. the replanted teeth were given a one-week healing period and then occlusion recovery was assessed, which resulted in decreased ankylosis and root resorption. The proliferative activity of PDL cells in the occluded group was generally higher than in the nonoccluded group. The activity of PDL cells in the recovery group was also higher than that of the nonoccluded group. In the hypofunctional condition of occlusal stimuli, marrow spaces had widened and elongated vertically : the activity of bone formation had decreased. On the other hand, in the recovery of occlusal function, the elongation of teeth was decreased and the activity of bone formation and regeneration had promoted.
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