Evaluation of Tensile Bond Strength of Nanoparticle Reinforced Soft Liner Materials: A Pilot Study

OBJECTIVE: The aim of this study is to evaluate the tensile bond strength between polymethyl methacrylate (PMMA) surfaces and autopolymerized silicon-based soft lining materials with 1% w/w Titanium dioxide (TiO2) and Hydroxyapatite (HA) nanoparticles added. MATERIALS AND METHODS: For the tensile test, 60 pieces of acrylic (Meliodent, Bayer Dental, Newbury, England) samples of 30 × 10 × 10 mm3 dimensions were prepared using metal molds. Acrylic surfaces were sanded with silicon carbide sandpapers of 500, 1000, 1500, and 2000 grids to ensure standardization. After the samples were placed back in the metal mold, adhesive (Detax, Germany) was applied to the surfaces that would come into contact with the soft lining. Soft lining materials (Mollosil, Detax, Ettlingen, Germany) to which 1% by weight TiO2 and 1% HA nanoparticles were added were polymerized by placing them between two acrylic blocks. For the tensile test, a total of 30 samples were obtained, with 10 samples in each group (n=10). The specimens were placed on the holder end of the universal test device and force was applied until failure occurred. RESULTS: The tensile bond strength (0,86 ± 0,21 MPa) in the TiO2 nanoparticle-added group was found to be significantly higher than the control group (0,65 ± 0,14 MPa) (p<0.05). There is no significant difference between the control group and the HA nanoparticle-added group (0.65 ± 0.1 MPa) (p˃0.05). CONCLUSION: It was observed that the addition of nanoparticles increased the tensile strength. However, further studies are needed to evaluate the effect of nanoparticle addition on other mechanical and physical properties of soft liners.