Effect of Milk and Soy-based Infant Formulas on In Situ Demineralization of Human Primary Enamel

Purpose: The effect of infant formulas sweetened or not with sucrose on primary enamel demineralization and dental biofilm is not known. This study's purpose was to evaluate the effect of infant formula and sucrose association on demineralization of primary enamel and dental biofilm formed. Methods: A cross-over, split-mouth, and blind in situ study was conducted during 3 phases, each of 10 days duration, during which 11 volunteers wore palatal appliances containing slobs of human primary enamel. The dental slabs were extraorally subjected 8 times a day to 6 groups of treatment: distilled and deionized water; 10% sucrose solution; and milk-based and soy-based formula with or without 10% sucrose added. After each phase, the acidogenicity, biochemical and microbiological composition of dental biofilm formed was analyzed, and enamel demineralization was assessed by microhardness. Results: Both formulas induced significant enamel mineral loss, which increased when sucrose was added. Both formulas were fermented, resulting in a decrease of biofilm pH, irrespective of sucrose addition. Also, lactobacilli counts were higher in biofilm formed in the presence of both formulas when compared to the water group. Conclusions: Milk and soy-based formulas present potential to induce demineralization in primary enamel, which increased when sweetened with sucrose. (Pediatr Dent 2010;32:35-40) Received August 20, 2008 I Last Revision January 22, 2009 I Revision Accepted January 25, 2009