The effect of pH and fluoride concentration of liquid dentifrices on caries progression

Objective This randomized clinical trial evaluated the effect of pH and fluoride concentration of liquid dentifrices (LD) on caries progression and fluoride uptake in the toenails of 2–4-year-old children. Materials and methods Schoolchildren living in a fluoridated area, with (A) or without (I) active caries lesions, were randomly allocated into three groups according to the LD they would use over 12 months: group 1 ( n = 48-A/56-I): 550 μg fluoride (F)/g, pH 4.5; group 2 ( n = 56-A/48-I) 1,100 μg F/g, pH 7.0; and group 3 ( n = 52-A/55-I): 550 μg F/g, pH 7.0. The number of lesions becoming active/cavities or inactive was clinically evaluated by determining progression or regression. Additionally, white spot lesions were evaluated by the quantitative light-induced fluorescence (QLF) method in 75 children. Toenail fluoride concentration was also evaluated. Data were analyzed by ANOVA and followed by Dunn's test or ANCOVA followed by Tukey's test ( p