Antimicrobial efficacy of chlorine agents against selected oral pathogens

ObjectivesMethod-dependent comparison of antimicrobial agents' efficacy against oral pathogens.Materials and methodsSeveral sodium hypochlorite solutions (NaOCl)-Perisolv(& REG;), Carisolv(& REG;) and Dakin's solution-were equated with chlorhexidine (CHX) and hydrogen peroxide (H2O2) against ten oral micro-organisms related to caries and periodontitis using different minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) techniques. Agents were adjusted to the final 70 mmol/L concentration of active chlorine molecule.ResultsApart from H2O2 and the amino acids of Perisolv(& REG;), all the agents revealed an antimicrobial effect. Agar diffusion test ranked CHX (p < 0.05) as the most effective against all ten specimens, followed by the NaOCl of Perisolv(& REG;) and Dakin's solution. Correspondingly, in broth microdilution on agar, CHX was the most effective in eradicating micro-organisms at 0.03 mmol/L compared with 2.2 mmol/L of Dakin's solution. In contrast, the bactericidal concentration of Dakin's solution was the most effective at 0.2 mmol/L, (p < 0.001), followed by Perisolv(& REG;) (2.14 mmol/L), CHX (2.38 mmol/L) and Carisolv(& REG;) (3.33 mmol/L) after 5 and 10 min in broth dilution test. In live/dead analysis, 60-min exposure to a 2-fold concentration of agents resulted in two-log Aggregatibacter actinomycetemcomitans inhibition by CHX (35 mmol/L) whilst Streptococcus mutans was more susceptible, in 0.8 and 8.8 mmol/L, after 10 min to CHX and Dakin's respectively.ConclusionReplacement of CHX with tested hypochlorite agents showed evident potential and promoted rapid antimicrobial effect.