THE EFFECT OF A VARNISH CONTAINING SELF-CURING RESIN ON THE SOFTNESS OF TWO TYPES OF TISSUE CONDITIONERS

Abstract

Objectives: One of the limitations of tissue conditioners (TC) is the gradual hardening of the material in a short time after insertion in the mouth. This study aimed to determine the softness of two different tissue conditioners with and without the coating made up of 1,1,1trichloroethan and self-curing acrylic resin.Materials and Methods: In this experimental study, Acrosoft (Marlic, Tehran, Iran) and GC (GC corporation, Tokyo, Japan) tissue conditioners were examined. 28 discs of 20 x 3 mm dimensions were prepared for each tissue conditioner (n=14). Half of the samples in each group were coated with varnish coating made up of 1,1,1trichloroethan and self-curing acrylic resin. The hardness of all samples was measured at five intervals of 1,3,7,14, and28 days by a Shore-A Durometer with a conical indenter. The data were analyzed by descriptive statistics and Friedman analyses. P<0.05 was considered statistically significant.Results: The mean hardness of the GC and Acrosoft tissue conditioners on days 1, 3, 7, 14, and 28 in both varnish-coated and non-varnish-coated groups were statistically different and Acrosoft tissue conditioner was harder than the GC. In the paired mean hardness comparison on days 1, 3, 7, 14, and 28 in the GV and G0 groups: this trend was the same in AV and A0 groups. The comparison of hardness in the GV and G0 groups at each time interval indicated that only on day 3, the control group(G0) was harder than the surface coating group(GV). The comparison of the hardness in the AV and A0 groups showed that on days 3 and 7, the hardness in the control group (A0) was higher than the surface coating group(AV).Conclusions: The varnish containing self-curing resin can soften the Acrosoft and GC tissue conditioner in a short time. Moreover, this varnish can be clinically applied in the borders between the soft liner and acrylic denture, which is usually the starting point for debonding.