Anticaries effectiveness of low-fluoride acidic dentifrice: a randomized clinical trial

In order to reduce the fluoride intake of children at the age of risk to dental fluorosis, the use of low-fluoride dentifrices has been suggested. However, there is still no consensus on their anticaries effectiveness. The reduction of the dentifrice pH has been suggested as an alternative to improve its efficacy. Objective: The purpose of this randomized double-blind clinical trial was to evaluate the effectiveness of a liquid dentifrice with reduced pH and low fluoride concentration for the prevention of new carious lesions. Methods: 1,402 4-year-old schoolchildren with caries experience were randomly allocated to 4 groups, differing according to the dentifrice used for 20 months: G1–liquid dentifrice (1,100 ppmF, NaF, pH 4.5, n=345), G2-liquid dentifrice (1,100 ppmF, NaF, pH 7.0, n=343), G3-liquid dentifrice (550 ppmF, NaF, pH 4.5, n=354), G4-commercial toothpaste (control-1,100 ppmF,NaF, pH 7.0, n=360). The liquid dentifrices and toothpaste were applied to the toothbrush using the “drop” (Vilhena et al. Caries Res 2006;40:304) and “transverse” (Villena et al. Pediatr Dent 2000;22:312-7) techniques, respectively. Caries progression (dmfs) was evaluated at baseline and 20 months after continuous use of the respective dentifrices. Data were analyzed by ANOVA (p<0,05). Results: 1,053 children were examined after 20 months (271, 262, 250 and 270 children for G1, G2, G3 and G4, respectively). Mean dmfs(±SD) at baseline, after 20 months and % increment were, respectively: G1) 5.07±5.11, 7.13±6.53 and 30.8%; G2) 4.80±5.00, 6.88±6.78 and 31.9%; G3) 5.24±5.37, 7.29±7.27 and 30.5%; G4) 5.05±4.89, 7.13±6.35 and 31.1%. No significant differences were found among the groups for all the variables tested. Conclusions: The results suggest that the low-fluoride (550 ppm F) acidic dentifrice has the same anticaries effectiveness as the conventional 1,100 ppm F dentifrices and seems to be a good alternative for small children. Support: FAPESP (05/03975-6 and 05/04090-8).