A randomised, observer-blind, clinical study investigating the effect of fluoridated milk on artificially created early enamel caries using transverse microradiography.

Much of the research regarding the efficacy of fluoridated milk was obtained prior to the routine use of fluoridated dentifrices. The aim was to investigate, in situ, the effect of fluoridated and non-fluoridated milk on mineral change in artificial caries lesions, with the additional use of fluoridated dentifrice. The roles of different milk fluoride concentrations, volumes and frequencies in mineral change were studied. In total, 29 edentulous subjects were recruited and tooth blocks, containing artificial caries lesions, were inserted into their full dentures at 4 areas (sites). Each subject followed 5 randomly ordered, 6-week beverage experiments: 0.5 mg of F in 200 ml of milk, 3 times per day; 1.5 mg of F in 200 ml of milk, once per day; 200 ml of milk, once per day; 200 ml of milk, 3 times per day, and no beverage (negative control). In addition, the subjects were allocated to 1 of 2 groups; experimental treatment only or treatment and dentifrice. Mineral change was measured with transverse microradiography. Statistical analysis was performed using 2-sample t tests and a general linear modelling procedure. For integrated mineral loss there was a statistically significant effect of group (p = 0.001), indicating fluoridated toothpaste significantly increased remineralisation. For lesion depth there was a statistically significant combined effect of 'group and site'. 'Experiment' had no statistically significant influence on change in integrated mineral loss or lesion depth. The study demonstrated that the use of fluoridated dentifrice twice per day had a positive effect on the remineralisation of caries lesions. However, no additional significant effect of fluoridated milk was observed.