Purpose: This study assessed the anti-erosive effect of Casein Phosphopeptide-Amorphous Calcium Phosphate (CPP-ACP), nano-hydroxyapatite (nano-HAP) and phosphorylated chitosan Amorphous Calcium Phosphate (Pchi-ACP) on enamel.
Materials and methods: A total of twenty five human incisors were ground and divided into five groups (n=5). Group1: intact enamel (negative control group) - Group 2: enamel + soft drink (positive control group). - Group3: enamel + soft drink+ CPP-ACP. Group4: enamel + soft drink+ 10% nano-HAP. Group5: enamel + soft drink+ Pchi-ACP. Four consecutive intervals of the immersion procedure were performed at 0, 8, 24 and 32 h for a total of 8 min. After each of the demineralizing immersion interval, the anti-erosive agent for groups 3, 4 & 5 was applied for 3 min. The total time for remineralization was 12 min. The root mean-square roughness (Rrms) was obtained from Atomic force Microscope images and the differences in the averaged values among the groups were analyzed by ANOVA, followed by Tukey's post hoc test. The level of significance was set at P < 0.05.
Results: Rrms of different groups at baseline was not statistically significant. However, after erosive demineralization, Rrms of group 2 increased and was significantly higher than all other groups. Rrms also significantly increased in group 3 subjected to CPP-ACP treatment after erosive demineralization. On the other hand, groups 4 and 5 did not show any significant change in Rrms.
Conclusions: This study had revealed that nano-HAP and Pchi-ACP are promising remineralizing nano-biomaterials