Comparison of the newer preventive therapies on remineralisation of enamel in vitro

Objectives: To investigate in vitro the effect of MI Paste, MI Paste Plus and 2800 ppm fluoride (F) toothpaste (TP) on the remineralisation of enamel subsurface lesions and to compare these to the effect of 1450 ppm and 0 ppm F toothpastes. Methods: Enamel subsurface lesions were created in bovine enamel slabs (n = 120) which were assigned randomly to five groups; (1) 0 ppm F TP, (2) 1450 ppm F TP, (3) 2800 ppm F TP, (4) 1450 ppm F TP + MI Paste (Tooth Mousse-TM,10% w/v CPP-ACP) and (5) 1450 ppm F TP + MI Paste Plus (Tooth Mousse Plus,10% w/v CPP-ACP, 900 ppm F as 0.2% w/w sodium fluoride). The enamel slabs were subjected to a pH cycling regimen for 21 days. Quantitative Light-induced Fluorescence (QLF) images were taken and analysed. Data analysis was carried out using one way ANOVA. Results: In all groups, both ΔF (percentage fluorescence loss) and ΔQ (ΔF times the area) values improved significantly within the same group after the treatment. In addition, the mean difference in ΔF of the non-fluoride control group was significantly lower than all other groups but not for the 2800 ppm F⁻ group. Whereas the mean difference in ΔQ of the non-fluoride control of group was significantly lower when compared with all other groups (p < 0.05). Conclusions: Both MI Paste and MI Paste Plus when used in conjunction with 1450 ppm F did not show a significant increase in efficacy for the remineralisation of bovine enamel subsurface lesions in the model used in this study. Clinical significance: Newer preventive agents such as MI paste and MI paste plus are advocated as promoting remineralisation when used in addition to routine oral care. This in vitro study shows that they may have a limited value in promoting remineralisation over and above that of 1450 ppm F toothpaste used twice a day