Shear Bond Strength Comparison Between Heat Cure Acrylic Resin and Other Types of Acrylic Denture Bases

Objective: The study purpose was to examine the shear bonding strength of heat cure acrylic resin to thermoplastic resin and three-dimensional printed resin materials. Methods: A total of 30 acrylic specimens were fabricated in this study. Each specimen had a basal and top parts. The basal part was rectangular in shape. We had three different groups: 10 specimens of a basal part made of heat cured polymethylmethacrylate, 10 specimens of a basal part made of thermoplastic, and 10 specimens of three dimensionally printed resin. The top part of which is attached to the basal one was formed into a cylindrical shape made of heat cure poly methyl methacrylate in all three groups. Results: Significant differences were found between the heat cured polymethylmethacrylate and the other two groups (P<.001). Heat cured polymethylmethacrylate showed the highest bond strength (75 MPa), and thermoplastic resins showed the lowest (37 MPa). No significant difference in the shear bond strength was noticed between three dimensionally printed and thermoplastic acrylic. Conclusion: This study revealed that the shear bond strength of heat cured acrylic denture base to the relining/repairing from the same material was significantly higher than three dimensionally printed and thermoplastic resins with HC relining/repairing material.