Alkyl‐bisbiguanides as in vitro inhibitors of bacterial growth and dental plaque formation

Nine anllogues of chlorhexidine, including Alexidine, in which the p‐chloroophenyl group had bneen replaced by straight or branched alkyl chains were found to be substantive ot saliva coated enamel. These alkyl bisbiguanides were also found to be antimicrobial in a tube dilution assay and tn prevent the formation of plaque in an in vitro plaque assay. Each of these compounds was found to be equal to or greater than chlorhexidine in antimicrobial or plaque inhibition activity against the periodontal organisms, Actinomyces viscosus and A. naeslundii. Against the cariogenic organism, Streptococcus mutans, each of these compounds was active but none had more active than several of the other analogues.