Evaluation of plaque pH changes following oral rinse with eight infant formulas.

Inappropriate feeding habits have been identified as major factors associated with the development of baby bottle tooth decay or nursing caries. An in vivo/in vitro combination technique was developed to investigated the plaque pH changes associated with rinsing with eight different infant formulas. These eight formulas represented four categories: 1) formulas with iron, 2) formulas with low iron, 3) soy formulas 4) and protein hydrolyzate formulas (from the manufacturers Mead Johnson Nutritionals and Ross Laboratories). All formulas had the ability to reduce the pH significantly below the pre-rinse plaque pH. Furthermore, the average minimum pH for formulas from the two manufacturers did not differ within each formula category except for the soy-based formulas, where, rinsing with Isomil produced a significantly lower plaque pH than ProSobee. These results suggest that infant formulas are acidogenic and therefore may play a significant role in the development of baby bottle tooth decay.