Actinomyces viscosus colonization of mouse teeth.

The implantation of Actinomyces viscosus strain T14V-J1 was studied in mice in vivo. The optimum age range for implantation was from 40 to 80 days. The minimum infective dose of strain T14V-J1 required for colonization in all inoculated animals (ID100) was 5 X 10(8) CFU for 40-day-old mice and 1 X 10(9) CFU for 100-day-old mice. The high ID100 required for implantation of strain T14V-J1 in these mice is consistent with the finding that tooth surfaces of these animals are not colonized by detectable indigenous Actinomyces. The infection could also be transmitted to non-infected mice housed with infected mice. This in vivo model can be used to evaluate the potential for reducing or preventing Actinomyces colonization on teeth by vaccination with fimbrial adhesins.