Microtensile bond strength of zirconia nanofillers reinforced acrylic resin to denture teeth after thermocycling

Abstract

Statement of problem: Addition of zirconium oxide nanofillers to PMMA had improved the mechanical properties of heat polymerized acrylic resin, but it's effect on bond strength to acrylic teeth hadn't been evaluated yet. Purpose: The purpose of the study was to evaluate the effect of Zirconium oxide (ZrO 2) nanofillers powder with different concentrations (1.5%, 3%, 5%) on bond strength of resin denture base to acrylic teeth before and after thermocycling. Material and methods: Zirconium oxide nanoparticles powder were added to heat cured (PMMA) with different concentrations (0, 1.5% ,3%, 5%). The base surfaces of 16 molar acrylic teeth were flattened, and zirconia reinforced heat-polymerized acrylic resin was applied to them. Thereafter, bar specimens were produced for the microtensile bond strength testing either before or after thermocycling. Results: The results showed that 5% ZrO 2 conc. recorded the highest value of microtensile bond strength. The lowest value was recorded in 1.5%, followed by 3%. Regarding thermocyling, the non-thermocycled groups always recorded higher values of microtensile bond strength either significant (1.5% & 5%) or insignificant (0% & 3%) than thermocycled ones at p < 0.05. Conclusions: Within the limitation of this study, it was concluded that reinforcement of acrylic denture base with zirconia nanofillers had significantly decreased bond strength with acrylic denture teeth in 1.5 % and 3% concentration; however, 5% had increased the bond strength values insignificantly. Thermocycling had reduced the bond strength in all concentrations.

The Effect of Salinized Nano ZrO2 Particles on the Microstructure, Hardness, and Wear Behavior of Acrylic Denture Tooth Nanocomposite

“…This procedure was accomplished by mixing 30 g of ZrO 2 nanoparticles with 0.3 g of TMSPM dissolved in 100 mL of acetone for 1 h with the help of a magnetic stirrer at 300 rpm (Hot plate with a magnetic stirrer, MSH-A 30A, Seoul, Korea) for 60 min. Subsequently, the solvent was removed using a rotary evaporator under vacuum for 30 min at 60 • C and 150 rpm, followed by heating for 2 h at 120 • C. Next, the treated powder was allowed to cool to 28 • C [28][29][30].…”