Pop-Cola Acids and Tooth Erosion: An In Vitro, In Vivo, Electron-Microscopic, and Clinical Report

Figure 2

Buffering capacities of pop-Cola drinks for a single unit pH change (orange) to critical pH 5.5 (red) and pH 7 (Green). The orange bars show Pepsi Cola having the highest buffering capacity while Diet-Coke and Selection Cola share the lowest buffering capacity. The red bars show buffering capacities for change from the drink’s initial pH up to the critical pH 5.5, with Diet Pepsi having the highest buffering capacity (1.9 mL of 0.5 M NaOH) while Coca Cola has the lowest buffering capacity (1.5 mL of 0.5 M NaOH). The green bars show buffering capacities for a pH change from the drink’s initial pH up to neutral (pH 7.0). Diet Pepsi has the highest buffering capacity (5.38 mL of 0.5 M NaOH), regular Selection Cola (3.78 mL of 0.5 M NaOH) has the lowest buffering capacity, and Coca Cola (3.79 mL of 0.5 M NaOH) is very similar and not significantly different from Selection Cola. All the cola-drinks absorb the alkali but vary in the amount of alkali to reach pH 7.