Comparison of growth and susceptibility to sodium hypochlorite of mono- and dual-species biofilms of Fusobacterium nucleatum and Peptostreptococcus (micromonas) micros.

This study compared growth and susceptibility to different concentrations of sodium hypochlorite (NaOCl) of mono- and dual-species biofilms of Fusobacterium nucleatum or Peptostreptococcus micros in vitro at 24 hours or 96 hours. A Mann-Whitney U test revealed that although at 24 hours dual-species biofilms had similar viable counts to those of monospecies biofilms (p > 0.001), they were more resistant to NaOCl (p < 0.001). At 96 hours, both microorganisms had higher viable counts and were more resistant to NaOCl in dual-species biofilms than in monospecies biofilms of the same microorganism (p < 0.001). As the age of the biofilms increased, so did their resistance to NaOCl. Mixed-species biofilms of F. nucleatum and P. micros showed a time-dependent synergy in growth and resistance to NaOCl.