Effect of two denture cleansers on tensile bond strength of a permanent resilient denture liner bonded to a conventional heat polymerized denture base resin

Aim: To study the effect of enzymatic and sodium perborate denture cleansers on tensile bond strength between permanent resilient liner and heat polymerized denture base immersed in different durations of immersion solutions. Materials and Methods: Sixty three samples with the resilient denture liner sandwiched between two polymerized PMMA blocks were divided into three groups A, B and C with 21 samples in each subgroup. All samples were stored in artificial saliva in an incubator at 370C for 15 days. They were then immersed in distilled water (Group A-Control group), enzymatic (Group B-Test group) and sodium perborate denture cleanser (Group C-Test group) for 8 hours once a day and repeated for fifteen days. Tensile bond strength values were evaluated using universal testing machine on 1st, 7th and 15th day. The type of bond failure was assessed using a stereomicroscope. The data was statistically analyzed using one way ANOVA (F-Test), Dunnett D test and Student’s paired t test. Results: Group A, B and C showed maximum tensile strength on 14th, 7th and 1st day respectively. Group A and B showed adhesive type of bond failure. Group C showed both adhesive and cohesive types of bond failure. The enzymatic denture cleanser showed more tensile bond strength compared to sodium perborate denture cleanser. Conclusion: This study demonstrated that there were significant differences among the samples for different types and durations of immersion solutions which are due to leaching out of plasticizers from resilient liner and composition of the different immersion solutions.