Effect of the Acquired Pellicle and of Dental Plaque on the Implantation of Streptococcus mutans on Tooth Surfaces in Man

Streptomycin (SM)-resistant Streptococcus mutans was implanted onto individual tooth surfaces by the topical application of heavy cell suspensions in buffer. The presence of an acquired pellicle or of 2-day-old dental plaque decidedly impaired implantation; the recovery of implanted, SM-resistant S. mutans was greatest when the labelled cells were applied directly on newly cleansed tooth surfaces. Even though S. mutans constituted only a very small proportion of the bacteria on each tooth surface, the number of S. mutans recovered was proportional to the total number of bacteria recovered.