Comparative evaluation of the spectral-domain optical coherence tomography and microhardness for remineralization of enamel caries lesions

Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) slows the progression of caries and remineralizes enamel subsurface lesions. The aim of this study was to determine the ability of CPP-ACP to increase the incorporation of fluoride into plaque and to promote enamel remineralization in situ. Randomized, double-blind, cross-over studies involved mouthrinses and dentifrices containing CPP-ACP and fluoride. The mouthrinses were used for 60 sec, three times/day for 5 days, and supragingival plaque was collected and analyzed for F. The dentifrices were rinsed as a water slurry for 60 sec four times/day for 14 days in an in situ model. The addition of 2% CPP-ACP to the 450-ppm-F mouthrinse significantly increased the incorporation of fluoride into plaque. The dentifrice containing 2% CPP-ACP produced a level of remineralization similar to that achieved with a dentifrice containing 2800 ppm F. The dentifrice containing 2% CPP-ACP plus 1100 ppm F was superior to all other formulations.

Aim: This in vitro study was conducted on enamel blocks of human premolars with the aim of evaluating the remineralization potential of fluoride and ACP-CPP and the combination of ACP-CPP and fluoride on early enamel lesions. Materials and Methods: Fifteen intact carious free human premolars were selected. The coronal part of each tooth was sectioned into four parts to make 4 enamel blocks. The baseline SMH (surface microhardness) was measured for all the enamel specimens using Vickers microhardness (VHN) testing machine. Artificial enamel carious lesions were created by inserting the specimens in demineralization solution for 3 consecutive days. The SMH of the demineralised specimens was evaluated. Then the four enamel sections of each tooth were subjected to various surface treatments, i.e. Group 1- Fluoride varnish, Group 2- ACP-CPP cream, Group 3- Fluoride + ACP-CPP & Group 4- Control (No surface treatment). A caries progression test (pH cycling) was carried out, which consisted of alternative demineralization (3hours) and remineralization with artificial saliva (21 hours) for five consecutive days. After pH cycling again SMH of each specimen was assessed to evaluate the remineralization potential of each surface treatment agent. Then, to asses the remineralization potential of various surface treatments at the subsurface level, each enamel specimen was longitudinally sectioned through the centre to expose the subsurface enamel area. Cross-sectional microhardness (CSMH) was evaluated to assess any subsurface remineralization Results: Statistical analysis using one-way ANOVA followed by multiple comparisons test was applied to detect significant differences at P ≤ 0.05 levels between various surface treatments at different phases. Conclusions: With in the limits, the present study concludes that; ACP-CPP cream is effective, but to a lesser extent than fluoride in remineralizing early enamel caries at surface level. Combination of fluoride and ACP-CPP does not provide any additive remineralization potential compared to fluoride alone. Fluoride, ACP-CPP and their combination are not effective in remineralizing the early enamel caries at the subsurface level.