The purposes of this study were ( 1 ) to investigate the effect of different milk formulas on dental plaque pH after rinsing with these three categories , type of protein-based formulas ( milk-based , soy-based , protein hydrolysate ) , type of sugar ( only lactose , lactose and other sugars , only non-milk extrinsic sugars ) , and casein ratio ( high and low casein ) , and ( 2 ) to observe organic acids formed by different milk formulas .
