A comparison of transverse strength of repaired poly(methyl methacrylate) resin denture base using conventional method, with glass fiber reinforcement and with ethyl acetate surface treatment: an in-vitro study

Fracture of poly(methyl methacrylate) resin denture base is a common clinical occurrence. The fractured denture base should be repaired as an interim or a definitive measure. The goal of denture repair is to restore its original strength and to avoid further fracture. Various materials and methods have been tried to increase the fracture resistance of the repaired area. The objective of the study is to evaluate the transverse strength of denture base resin repaired by different methods, after ethyl acetate surface treatment and glass fiber reinforcement, and compare it with denture base acrylic resin repaired by conventional methods.

ADA specification No. 12 was used as a guideline for preparing the specimens. 120 standard heat polymerizing acrylic resin strips were fabricated using a customized brass flask, and were repaired to obtain 60 specimens. Of the 60 specimens, 10 each were repaired using, autopolymerizing acrylic resin (with and without surface treatment), heat polymerizing acrylic resin (with and without surface treatment), 1% glass fiber reinforced autopolymerizing acrylic resin with ethyl acetate surface treatment, and 1% glass fiber reinforced heat polymerizing acrylic resin with ethyl acetate surface treatment. These specimens were tested for transverse strength on an Instron testing apparatus. The findings were statistically analyzed using one way analysis of variance (ANOVA) and Tukeys HSD test.

The transverse strength values of samples, repaired after ethyl acetate surface treatment, were higher when compared to untreated samples. Transverse strength values of samples, repaired with ethyl acetate surface treatment and glass fiber reinforcement material, were the highest.

Surface treatment with ethyl acetate improves the repair strength. Surface treatment with ethyl acetate and incorporation of glass fiber reinforcement material provides greatest repair strength.