Effect of Artificial Saliva, Bioactive Glass and Fluoride Varnish on Micro-hardness and Micro -shear Bond Strength of Demineralized Enamel Surface

Objectives: the aim of this study was to compare the effect of 3 different remineralizing agents on microhardness and microshear bond strength of demineralized enamel surface.
Materials and methods: A total of 50 teeth were divided into five groups (10 each) that were summarized as follows: Group 1: sound unprepared teeth (base line control); Groups 2: demineralized enamel (negative control). Group 3: demineralized enamel stored in artificial saliva for one month. Group 4: demineralized enamel treated by bioactive glass (sylic powder). Group 5: demineralized enamel treated by fluoride varnish (positive control). Five samples from each group were used to test the micro-hardness and the other five samples were used to microshear bond strength.
Results: A statistical significant difference was found in microhardness between the sound enamel group and both of the demineralized enamel and the fluoride varnish test groups ,meanwhile no statistically significant difference was found between sound enamel group and both of the artificial saliva test group and the Sylc powder test group. Also, there was a statistically significant difference in microshear bond strength between sound enamel and each of demineralized enamel, demineralized enamel with artificial saliva, demineralized enamel with Sylc powder and demineralized enamel with Fluoride varnish.
Conclusion: The two remineralizing agents; bioactive glass and artificial saliva are capable of enhancing microhardness and micro shear bond strength of demineralized enamel more effectively than fluoride varnish .