Comparative Evaluation of Tensile Bond Strength of Two Soft Liners Bonded to Heat-Cured and 3D-Printed Denture Base Materials

Abstract

The study was conducted to evaluate the tensile bond strength between acrylic-based and silicon-based denture liners bonded to conventional heat-cured PMMA and 3D-printed denture base materials. Materials and Methods: A total of forty dumbbell-shaped specimens were fabricated for the test of tensile bond strength with dimensions 75 mm in length, 12mm in diameter at its thickest portion, and 7 mm at its thinnest section. The specimens were divided into two equal groups (n=20) depending on the denture base material (conventional heat-cured PMMA and 3D- printed) and each group was subdivided into two subgroups (n =10) depending on the material of soft liner bonded to it, subgroup A: Acrylic-based soft liner and subgroup B: Silicon-based soft liner. Results: The silicon-based soft liner bonded to conventional PMMA recorded the highest tensile bond strength while the least value for bond strength mean was recorded by the acrylic-based liner bonded to the 3D-printed denture resin. Conclusion: The silicon-based soft liner showed greater bond strength to conventional PMMA and 3D-printed denture bases than the acrylic-based soft liner.