Enhanced bactericidal activity of Arm and Hammer Dental Care.

ABSTRACT

PURPOSE: To compare and contrast antibacterial activities of a baking soda-containing dentifrice, Arm and Hammer Dental Care (AHDC) with two fluoride dentifrices without baking soda (Crest and Colgate). MATERIALS AND METHODS: A biphasic approach was taken, utilizing newly-developed laboratory model systems to (1) assess the activity of brief exposure to dentifrices on single and mixed cultures; and (2) determine the effect of multiple, short-term exposure of sucrose-colonized Streptococcus mutans to simulate cumulative activity against cariogenic plaque. RESULTS: The short-term exposure assays revealed that S. mutans was significantly more susceptible to AHDC than either Crest of Colgate (P<0.05). Moreover, exposure of mixed suspensions of bacteria by AHDC resulted in complete killing of Actinomyces viscosus and significantly greater decreases in S. mutans (P<0.05). This enhanced bactericidal effect was not due to an alkaline pH as pH-adjusted AHDC solutions exhibited similar activity. The comprehensive in vitro plaque studies showed that exposure of colonized S. mutans to AHDC resulted in significantly greater decreases in numbers of viable cells than Crest (P<0.05). Under the conditions employed, the baking soda-containing AHDC exhibited greater antibacterial efficacy overall than the standard Crest or Colgate pastes. These studies suggest that the use of AHDC may provide additional clinical benefit as a result of the enhanced bactericidal activity.