Project/Area Number |
11671950
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
補綴理工系歯学
|
Research Institution | Tokyo Dental College |
Principal Investigator |
HASEGAWA Koji Tokyo Dental College, Department of Dentistry, Lecturer, 歯学部, 講師 (70218444)
|
Project Period (FY) |
1999 – 2001
|
Project Status |
Completed (Fiscal Year 2001)
|
Budget Amount *help |
¥2,700,000 (Direct Cost: ¥2,700,000)
Fiscal Year 2001: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 2000: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 1999: ¥700,000 (Direct Cost: ¥700,000)
|
Keywords | ceramic / Core build up / copy grinding / 破壊試験 / 人工歯根モデル / 牛歯 |
Research Abstract |
Glued a ceramic dowel core system to a model. Cut off at median plane and measured a cement film thickness. As a result of measuring of a core and a margin was minimum 5 μm maximum 90 μm. The fitting of root canal orifice wihich was a sharp edge and a ceramics core were bad, and the maximal cement film thickness was 200 μm. The cement film thickness of a post-part was 5-50 μm. The cement film thickness for a part of apex of post was 50 μm and 8μm. The ceramic dowel core system were glued to a model using Superbond, and a compressive strength was conducted from an angle of 120.8°using a universal testing machine. The average maximum fracture load was 27.4°kgf(SD : 9.2) for the ceramic dowel core system and 30.2kgf(SD : 8.8) for the prefabricated post & composite core (the control). Fracture occurred at the tooth margin and the crown edge on the side to which the load was applied in the ceramics post-core system and the control. Nonetheless, the type of fracture did not differ significantly among all specimens. In addition, fracture and cracking were not detected in the ceramic core or at the joint between the existing root-canal post and the ceramic core. These findings suggest that the usefulness of the ceramic dowel core system is equivalent to or higher than that of the control.
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