Figure 5. The effect on plaque pH levels of rinsing for 2 min, first with 100 mL of a 1% and then with 100 mL of a 20% (w/v) glucose solution. Each point is the mean pH of 2 plaque sites in each of five subjects. Each rinse was divided into two 50-mL portions, and rinsing with each was for 1 min (adapted from Kleinberg et al., 1981).