Toothpasts Formula Retaining Activites of Cationic Antimicrobials

Abstract

Toothpaste formulae having the ideal rtheological property without inactivation of cationic antimicrobials such as cetylpyridnium chloride and chlorhexidine digluconate were developed and investigated.
Experimental tothpastes containing polyquaternium 10 (M. W. 2 million) or a high concentration of poloxamer 238 as a gelling agent were prepared. As a control, the toothpaste containing celulose gum that is anionic polymer was also prepared. All these tothpastes contained a cationic antimicrobial agent.
The bactericidal activities were retained in experimental toohpastes consisting of polyquaternium 10 or a high concentration of poloxamer 238 but not retained in the control tothpaste consisting of cellulose gum.
A non-Newtonian index, which had a positive correlation with pseudoplasticity, was introduced for evaluation of the rheological property. The indices of the above mentioned experimental toothpastes were higher than those of the control toothpaste and showed little change in spite of a change in viscosity.
Furthermore, in the delivery of cationic antimicrobials to saliva-coated hydroxyapatite disk, the toothpaste consisting of polyquaternium 10 was superior to that consisting of poloxamer 238.