Root caries lesions inhibition and repair using commercial high-fluoride toothpastes with or without tri-calcium phosphate and conventional toothpastes containing or not 1.5% arginine CaCO(3): an in situ investigation.

OBJECTIVES: This double-blind, crossover, and in situ study evaluated the effect of commercial high-F toothpastes with or without functionalized beta-tri-calcium phosphate (fTCP) and conventional-F toothpaste containing or not 1.5% arginine-CaCO(3) in preventing and repairing root caries-like lesions. METHODS: Twelve volunteers wore palatal appliances containing sound (S) and pre-demineralized (PD) bovine root dentin blocks in 4 phases of 14 days/each. They used F toothpastes, 3x/day: (i) 1,450 mug F/g (conventional-F); (ii) 1,450 mug F/g + 1.5% arginine-CaCO(3) (conventional-F + arginine/CaCO(3)); (iii) 5,000 mug F/g (high-F); and (iv) 5,000 mug F/g (high-F + fTCP). Sucrose solution (20%) was dropped 8x/day on the S blocks. The demineralization in the S blocks and the remineralization in the PD ones were estimated by % of surface hardness difference (%SH-S) and % of SH recovery (%SHR-PD), respectively. Caries lesion area (DeltaS) was determined in the blocks. Statistical analyses were performed by one-way ANOVA/Kruskal-Wallis and multiple comparisons tests (p < 0.05). RESULTS: Both high-F toothpastes presented similar effect to prevent early caries lesions and it was higher than conventional-F + arginine/CaCO(3.) All treatments resulted in significantly lower DeltaS values compared with conventional-F toothpaste (p < 0.0001). High-F + fTCP showed non-significantly higher preventive and reversible effect compared to high-F. The effect of conventional-F + arginine/CaCO(3) was similar to high-F and lower than high-F + fTCP in preventing and reverting in-deep caries lesions. CONCLUSIONS: Overall, high-F toothpastes seem to be more effective and interesting feasible strategy for both prevention and remineralization actions in root dentin. CLINICAL RELEVANCE: With the trend of increasing dentin root caries, this study brings new evidences about the preventive and repair effect of high-F toothpastes with or without fTCP in root caries and support the use of arginine in toothpastes.