The effect of recasting on the castability of the prepared Co-Cr dental base-metal casting alloys

Abstract EN

Background: The use of Co-Cr alloys in dentistry has gained wide popularity in recent years and the RPD is the primary application of this alloy.

From economic point of view, the casted alloy may be mixed with new alloy in different proportion.

The aim of this study is to evaluate the effect of recasting process on the castability value of prepared Co-Cr dental base-metal casting alloy and compare it with other commercially available alloy.

Materials and methods: The prepared Ni-Cr alloy was locally prepared in Iraq by Al-Khafagy (2003), while the Wirocast Ni-Cr was used as conventional alloy.

A wax mesh of 1mm opening and (10*10) segments square was invested in phosphate-bonded investment and casted by using induction casting machine.

The number of complete cast segments was counted, divided by 220 and multiplied by 100 to obtain a percentage designated the castability value (Cv).

Results: The prepared Co-Cr alloy showed higher castability values than the Wirocast alloy regarding all the tested groups.

However, there were non significant differences between the two groups.

ANOVA test revealed a non-significant differences within the groups regarding the conventional alloy and significant regarding the experimental alloy Conclusion: Recasting has no effect on the castability value regarding the conventional alloy while the prepared Co-Cr alloy may be recasted only with proportion of 50% used alloy and 50% new alloy without possible changes in the castability values.

Key word: Castbility, casting behavior, Co-Cr alloy, recasting.

(J Bagh Coll Dentistry 2007; 19(1)24-27)