Effect of a gypsum hardener on the surface quality of stones casts obtained from alginate and silicone rubber base impression materials

ABSTRACT

This article was conducted to study the effect of Epoxy resin [Araldite] as a hardening agent on the surface quality of commonly used dental stone die material [Moldano] as regards compatibility, reproduction of fine details, surface hardness and surface morphology of stone casts obtained from alginate [CA 37] and silicone rubber base [xantopren and Optosil] impression materials. Twenty stone casts were prepared against each type of I. M. These casts were classified as following Group I [Control group] consisted of 5 casts were prepared according to manufacturers instructions without additive. w/p ratio 0.3.- Group II[a]Consisted of 5 casts which were constructed by adding 2.5% by weight epoxy resin to the mixing water just before mixing with powder. Group II[b] 5 casts were prepared by adding 5% by weight epoxy resin to the mixing water. Group II[c] 5 casts were prepared by adding 10% by weight epoxy resin to the mixing water. Multifactorial experiments were carried out on the different groups and evaluated according to the A.D.A. specification No. 25 for gypsum products