Efficacy of an Experimental CPP-ACP and Fluoride Toothpaste in Prevention of Enamel Demineralization: An In Vitro Study on Bovine Enamel.

Abstract

Objective: This study evaluated the effects of adding casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), with and without fluoride, to a laboratory toothpaste on the inhibition of enamel demineralization under pH cycling conditions. Methods and Materials: A total of 44 enamel blocks were prepared. Samples were randomly divided into four groups: Group 1-Basic laboratory toothpaste as control; Group 2-Laboratory toothpaste containing 1100 ppm sodium fluoride; Group 3-Laboratory toothpaste containing 1% w/w CPP-ACPF; Group 4-Laboratory toothpaste containing 1% w/w CPP-ACP. Half of each enamel block was coated with nail varnish (sound area), and the other half was subjected to pH cycling for 10 days. During this period, the samples were immersed in a demineralization solution for three separate periods of 1 h each (3 h in total). In the remaining intervals, they were immersed in a remineralization solution (21 h in total). After the first step of demineralization, samples were immersed in an aqueous solution of the toothpaste and distilled water for 6 min. Vickers microhardness was measured at depths of 20, 50, and 120 μm. Results: The relative demineralization (rDEM) index in all treatment groups was significantly smaller than that in the control group. Binary analysis showed that there was no significant difference in the rDEM among the treatment groups, regardless of depth. Tukey's post hoc test revealed that the amount of hardness reduction due to the pH cycle was significant in all groups and at all depths, except for Group 4 at 50 and 120 μm depth. Therefore, CPP-ACP is more effective in preventing demineralization. Conclusion: All three remineralizing agents inhibited enamel demineralization; however, CPP-ACP was more effective at depths of 50 and 120 μm.