Rinsing with water for 1min after milk formula increases plaque pH.

Abstract

Parents find it challenging to follow recommendations to brush young children after feeds at night despite the increase caries risk. This study compared three clinical recommendations (dilution, rinsing and wiping) on plaque pH after formula consumption. Eighteen subjects were recruited. The five interventions with 2-week washout between visits included: Rinse with undiluted formula for 30s (UF); rinse with 50% diluted formula for 30s (DF); rinse with undiluted formula for 30s, followed by rinsing with water for 1 minute (UF/R); rinse with undiluted formula for 30s, followed by wiping (UF/W); rinse with 10% sucrose for 30s as control (C). Plaque samples were collected at baseline, 2, 5, 10, 20 and 30min after the intervention and pH measured using the plaque sampling method. UF/R resulted in significantly smaller pH drops at 5, 10 and 20min compared to UF. It also resulted in higher minimum pH (UF/R: 6.34 ± 0.36 Vs UF: 6.06 ± 0.40, p = 0.02), smaller maximum pH drop (UF/R: 0.63 ± 0.35 Vs UF: 0.90 ± 0.49, p = 0.03), smaller sum of change of hydrogen ion concentration (UF/R: 9.22 × 10-7 ± 7.8 × 10-7 Vs UF: 2.30 × 10-6 ± 2.6 × 10-6, p = 0.04), and smaller area under the curve (UF/R: 7.70 ± 5.44 Vs UF: 13.44 ± 9.44, p = 0.02). DF and UF/W did not result in any significant pH change compared to UF. Of the three clinical recommendations, only rinsing with water for 1min after undiluted formula reduced plaque acidogenicity. Teeth wiping with a moist cloth and 50% dilution of infant formula did not have an effect on plaque acidity.