To Compare and Evaluate the Bond Strength of Acrylic Denture Teeth with Heat Cure Acrylic Resin and Thermoplastic Denture Base Material after Different Surface Treatments of Acrylic Teeth - An In Vitro Study

Background: Denture teeth made of acrylic resin are preferred because they chemically bond to denture base material but the problem of debonding is also common with the use of acrylic teeth. Many attempts have been done to improve bond strength of acrylic teeth which involves mechanical and chemical means. With the use of recently introduced thermoplastic denture base materials, the problem of tooth debonding has been increased due to the mechanical nature of the bond between these materials and the acrylic teeth. There is limited literature on bond strength of acrylic teeth and flexible denture materials and the methods to enhance it. The present study evaluates and compares the bond strength between acrylic teeth and heat cure resins and thermoplastic resins after different known denture tooth surface treatment methods, including use of methyl methacrylate; sandblasting and prefabricated vertical groove. Method: A total of 180 maxillary right central incisors were selected and divided into six groups of 30 samples each, according to the surface treatments and denture base material (heat cure or thermoplastic resins) used for processing. The bond strength of all specimens were tested in Universal Testing Machine. The obtained data were subjected to statistical analysis. Result: Results showed that there was statistical significant difference in mean bond strength after various surface treatments and processing of acrylic teeth with either heat cure or flexible denture material. Interpretation & Conclusion: The present findings suggest that vertical groove in the ridge lap area has highest bond strength amongst the groups processed with flexible denture material, and treatment of specimens with methyl methacrylate monomer for 5 sec has highest bond strength amongst all groups.