Effects of a Multifunctional Dentifrice on Dentin Microhardness and Dentinal Tubule Occlusion: An In Vitro Study

Objective: This in vitro study aimed to evaluate the effects of a multifunctional dentifrice containing tricalcium phosphate, sodium fluoride, sodium metaphosphate, potassium nitrate, and tocopherol acetate on dentin microhardness and dentinal tubule occlusion.Methods: Bovine dentin specimens were prepared and treated with either a control dentifrice or an experimental multifunctional dentifrice.Surface microhardness was measured at baseline, day 7, and day 14 using a microhardness tester.Dentinal tubule occlusion was assessed after 7 and 14 days by scanning electron microscopy, and occlusion scores were quantified at 5,000 magnification.Intergroup comparisons were performed using independent two-sample t-tests.Results: At baseline, no significant difference in dentin microhardness was observed between the groups.After 14 days, the experimental group showed significantly higher microhardness values than the control group (p=0.003).Dentinal tubule occlusion scores were significantly greater in the experimental group than in the control group at both day 7 (p=0.007)and day 14 (p0.001). Conclusion:Within the limitations of this in vitro study, the multifunctional dentifrice demonstrated superior preservation of dentin microhardness and enhanced dentinal tubule occlusion compared with the control dentifrice.Further clinical studies are required to confirm these findings under oral conditions.