Effect of Surface Treatments with Plasma and Chemical Bond on Shear Bond Strength of Acrylic Denture Teeth to Flexible and Heat-Cured Denture Base Material: An In Vitro Study

Introduction: We aimed to evaluate the shear bond strength of acrylic denture teeth to flexible and heat-cured denture base material after surface treatments with argon plasma, chemical bonding agent (PALFIQUE universal), and combination. Methods: A total of 80 incisor acrylic denture teeth were treated with a argonplasma, chemical bond (PALFIQUE universal bond), and a combination with 10 samples for each group. The neck (gingival portion) of teeth was cut at a 45° angle, and the teeth were attached to heat-cured acrylic resin and flexible denture base material. All the specimens were stored in artificial saliva for 7 days in an incubator (37 °C). A shear bond strength test was conducted using an Instron universal testing machine. Data were analyzed by the analysis of variance (ANOVA) and the Tukey’s honest significant difference post hoc test using R 4.2.3. Results: A statistically significant difference was found among study groups regarding the type of base, surface treatment with bond, plasma, and combination of bond and plasma (P < 0.00). The Tukey’s test showed that in a heat-cured base, the difference between the control and surface treatment with bond was not significant (P > 0.05). Also, in the flexible base group, the difference between the control and surface treatment with plasma was not significant (P = 0.162). Conclusion: In heat-cured denture-base group, the shear bond strength increased significantly with the combination of surface treatment with argon plasma and a chemical bonding agent (PALFIQUE universal). In the flexible denture-base group, the shear bond strength increased significantly with use of a surface treatment with a chemical bonding agent (PALFIQUE universal).