Enhanced Fluoride Bioavailability with Incorporation of Arginine in Child Dentifrices

To: 1) examine the fluoride concentrations in commercial child formula dentifrices (CFD)s; and 2) investigate the effect of arginine incorporation in CFDs on fluoride bioavailability.

Five commercial CFDs were examined for fluoride concentrations. Total, total soluble, and insoluble fluorides in CFDs were determined by the modified Taves acid-diffusion method (TAD). Ionic F and MFP were estimated by modified direct method with standard addition technique. L-arginine (L-Arg)/L-arginine monohydrochloride (L-Arg.HCl) were incorporated at 2% w/w in the commercial CFDs. The pH of the toothpaste slurries, buffer capacity of the added Arg, potentially available fluorides (PAF) and 1-min PAF by TAD were determined.

The CFDs had 4 to 32% of insoluble fluorides. Addition of L-Arg/L-Arg.HCl significantly improved the fluoride bioavailability in CFDs (p<0.05). Incorporation of L-Arg significantly increased the pH of toothpaste slurries (p<0.05); while L-Arg.HCl decreased the pH. Principal component analysis showed that L-Arg.HCl decreased the pH of toothpaste slurries due to the presence of Cl in the form of HCl; whereas the inherent elements/molecules (Na/P/Pi/F) remain distinct with unidentified influence on the variables.

The CFDs containing NaF only have higher concentrations of bioavailable fluoride. Incorporating arginine (L-arginine or L-arginine monohydrochloride) at 2% w/w improves fluoride bioavailability of the child formula dentifrices.