Abstract:
Purpose: To evaluate the effect of a desensitizing toothpaste, containing calcium sodium phosphosilicate, on microtensile bond strength of adhesive systems treated to dentine.
Methods: Fifty-two human third molars were embedded into acrylic resin, and cut to expose flat dentin surface. The specimens were randomly divided into two groups, 1) no brushing, and 2) brushing with Sensodyne Repair&Protect (GSK, London, UK) for 10,000 cycles with a V-8 cross brushing machine (Sabri Dental Enterprise, Inc., USA). Subsequently, both groups were divided into three groups for resin composite build-up using different adhesive agents (OptiBond FL® (Kerr, Orange, CA, USA), Clearfil SE Bond® (Kuraray Medical Inc, Japan), Single Bond Universal® (3M ESPE, USA)). All samples were subsequently sectioned to obtain microtensile test specimen, after which the sectioned sticks in the same tooth were divided into two subgroups: 1) microtensile bond strength test, and 2) thermocycling for 10,000 cycles, followed by microtensile bond strength test.
Results: Two-way ANOVA revealed that μTBS values of each adhesive system was not significantly affected by brushing with desensitizing toothpaste containing calcium sodium phosphosilicate. After brushing with desensitizing toothpaste containing calcium sodium phosphosilicate, OptiBond FL® had a significant highest μTBS value. Clearfil SE Bond® showed no significant different immediate μTBS value compared to Single Bond Universal®, but showed a significant higher μTBS value than Single Bond Universal® after 10,000-cycle thermocycling. In addition, 10,000-cycle thermocycling significantly decreased the μTBS value of Single Bond Universal® after brushing.
Conclusion: Desensitizing toothpaste containing calcium sodium phosphosilicate had no effect on OptiBond FL® Clearfil SE Bond® and Single Bond Universal® adhesive in both immediate μTBS or after 10,000-cycle thermocycling. In addition, 10,000-cycle thermocycling significantly reduced μTBS value of Single Bond Universal® brush group.
