Studies on Titanium-Zirconium alloy in clinical application

1994 Fiscal Year Final Research Report Summary

• Project/Area Number: 05452334
• 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: Ohu University
• Principal Investigator: NOGUCHI Hakuju Ohu university School of Dentistry Professor, 歯学部, 教授 (80083434)
• Co-Investigator(Kenkyū-buntansha): NAGAYAMA Katsuya Ohu university School of Dentistry Professor, 歯学部, 教授 (40105630) ; MASUHARA Eiichi Ohu university School of Dentistry Professor, 歯学部, 客員教授 (00013772)
• Project Period (FY): 1993 – 1994
• Keywords: Titanium・zirconium alloy / Casting accuracy / Castability / Investment / Thermal expansion

Research Abstract

Trial product and a commercially available investments and two types of casting apparatus were employed in this study. The castability was evaluated regarding the different liquid-to-powder ratio of investment and casting system (spin type centrifugal, pressure-aspirated type).
The casting behavior was found to be good by using a square wax grid pattern. An excellent castability was attained in the high liquid-to-powder ratio of investment. By using the spin type centrifugal casting apparatus, gas permeability of investment had little influence on castability, but by using the pressure-aspirated type, it exerted much influence.
On the other hand, the casting accuracy was determined as a gap between the margin of the castings and the gingival margin of the metal mold measured by means of measuring microscope.
The casting accuracy was found to be good by using a commercially available investment. An excellent casting accuracy was attained in the low liquid-to-powder ratio and the long burn out time at the temperature of 900ﾟC.The results of this study indicate that the volume expansion of 0.6% is necessary for investment to produce the good adaptability between Ti-Zr alloy castings and the mold.