Effect of CPP-ACP on Hardness of Enamel Eroded by Cola-drink

Objective: This in vitro study evaluated the remineralization effect of Casein Phosphopeptide-Amorphous Calcium Phosphate (CPP-ACP) from Toothmousse (GC Asia Dental, Japan) on hardness of enamel eroded by Cola-drink. Methods: Ten extracted human premolars were bucco-lingually cut into 2 halves and embedded in resin providing 20 specimens with buccal and lingual experimental sites. The specimens were polished (1 micron diamond slurry, Imptech, South Africa) and baseline Vickers hardness was measured (100g force, 15s) to demonstrate the effect of mineral changes. The demineralization process was done by immersion of specimens in Cola-drink (Thai Namthip Co.Ltd, Thailand) and artificial saliva (Chulalongkorn University, Thailand) (5s each for 10 cycles) for 3 times with 2 immersions in artificial saliva for 6h among the 3 alternate immersions. All specimens were rinsed with deionized water and the hardness measurements were repeated. For remineralization process, the demineralized specimens were randomly divided into 4 groups (n=10) and 4 regimens of remineralization used CPP-ACP (group 1), artificial saliva (group 2), CPP-ACP and artificial saliva (Group 3) and deionized water as control. After remineralization process, hardness measurements were repeated. Statistical analysis used Oneway ANOVA followed by Bonferroni test (alpha = 0.05). Results: The hardness of the specimens at baseline, after demineralization and after remineralization of group 1 (246.7±3.2, 209.1±13.6, 247.3±5.2), group 2 (245.2±6.4, 207.9±7.8, 228.1±9.2), group 3 (248.3±6.2, 205.6±6.5, 242.6±12.1) and control group (239.1±17.9, 207.0±8.2, 210.0±8.5) were demonstrated with standard deviation respectively in bracket. After remineralization, all groups showed significantly higher hardness value than control (p<0.05). The CPP-ACP and CPP-ACP with artificial saliva groups demonstrated significantly higher hardness value than the artificial saliva group (p<0.05). Conclusion: CPP-ACP from Toothmousse can increase hardness of enamel eroded by Cola-drink. The remineralization effect of CPP-ACP is significantly higher than that of artificial saliva in vitro.