OBJECTIVEThe aim of this study was to investigate whether the three species of oral Actinomyces have inhibitory effects on the growth of oral Candida albicans in vitro.

METHODSStraight o'clock method was used to observe the bacteriostasis circle. Reverse o'clock and mixed culture method were used to study the quantitative changes of Candida albicans colony respectively.

RESULTS(1) None of the groups had been viewed the bacteriostasis circle. (2) Compared with control groups, there was a significant decrease of Candida albicans colony on Actinomyces viscosus TPY soft agar (P < 0.05). Actinomyces naeslundii and Actinomyces odontolyticus TPY soft agar were both devoid of obvious Candida albicans colony (P < 0.01). The former group (Actinomyces viscosus) and the two latter groups (Actinomyces naeslundii and Actinomyces odontolyticus) showed a striking contrast (P < 0.01). (3) Compared with control groups, a decrease of Candida albicans showed up in the mixed culture, and the difference was significant (P < 0.05). The discrepancies among the three experimental groups were of no statistical value (P > 0.05).

CONCLUSIONOral Actinomyces viscosus, Actinomyces naeslundii and Actinomyces odontolyticus could inhibit the growth of Candida albicans in vitro. However, which of them contributed more to the inhibitory effects was still not affirmed.