A Study on Clinical Evaluation of Dental Casting Alloys

Research Project

Project/Area Number	60480420
Research Category	Grant-in-Aid for General Scientific Research (B)
Allocation Type	Single-year Grants
Research Field	補綴理工系歯学
Research Institution	Tokyo Medical and Dental University
Principal Investigator	MATSUI Yuko Tokyo Medical and Dental University, 歯学部, 助手 (20143604)
Co-Investigator(Kenkyū-buntansha)	INOUE Masayuki Tokyo Medical and Dental University, 歯学部, 助教授 (10013872) TABATA Tsuneo Tokyo Medical and Dental University, 歯学部, 教授 (20013849)
Project Period (FY)	1985 – 1986
Project Status	Completed (Fiscal Year 1986)
Budget Amount *help	¥6,700,000 (Direct Cost: ¥6,700,000) Fiscal Year 1986: ¥900,000 (Direct Cost: ¥900,000) Fiscal Year 1985: ¥5,800,000 (Direct Cost: ¥5,800,000)
Keywords	dental casting alloy / clinical test / corrosion surface / EPMA
Research Abstract	The following experiment was performed for the purpose of examining changes of dental casting alloys in human mouths. Class <II> cast inlays were fabricated with four kinds of dental casting alloys and had been temporarily fixed in molars of several young adults for 1 and 3 months. After 1 or 3 months temporary cementation, surface changes of each alloy were observed by SEM and the chemical composition was also analyzed by EPMA. The results are as follows. (1) Gold alloy and Ag-Pd-Cu-Au alloy showed very few changes in surface and there were few changes observed in chemical composition of both alloys in mouths. (2)Ag-Sn-Zn alloy was obviously changed in surface and remarkable changes were seen especially on buccal and gingival sides of proximal surface. (3)Though 70Ni-19Cr alloy showed remarkable changes in vitro and in vivo, few changes were observed in mouths. The cause of these results are now examining.