RESUMEN
OBJECTIVE: The aim of this study was to determine the antibacterial effect of different formulations containing Lysozyme and Lactoferrin and drug delivery system as well as poloxamer 407 with the trade name of Pluronic F-127 and/or freeze dried liposome containing DOTAP [freeze dried Liposomal DOTAP] on Streptococcus sobrinus, Streptococcus mutans and Lactobacillus acidophilus in comparison with 0.2% chlorhexidine. MATERIALS AND METHODS: The antibacterial effect was assessed by determining the minimum inhibitory concentrations (MIC) for the study and control groups on Streptococcus sobrinus, Streptococcus mutans and Lactobacillus acidophilus. The amounts of biofilm formation accumulation of Mutans Streptococci for 24h on sterile hydroxyapatite discs after application of different formulations were evaluated. The different formulations studied were: (1) Sorensen's Buffer Solution, (2) a gel formulation containing only poloxamer 407, (3) Lysozyme and Lactoferrin dissolved in Sorensen's Buffer Solution, (4) poloxamer 407 combined with the third formulation, (5) Freeze dried Liposomal DOTAP dissolved in Sorensen's Buffer Solution, (6) Freeze dried Liposomal DOTAP combined with poloxamer 407 dispersed in Sorensen's Buffer Solution, (7) Freeze dried Liposomal DOTAP combined with the third formulation, and (8) Lysozyme and Lactoferrin dissolved in Sorensen's Buffer Solution, which was then incorporated into poloxamer 407 and combined with Freeze dried Liposomal DOTAP. The positive and negative control groups were 0.2% chlorhexidine gel and empty hydroxyapatite discs, respectively. Statistical evaluation was carried out with Kruskal-Wallis and Dunn's multiple comparison tests. RESULTS: It was observed that the first, third and fifth groups did not have any antibacterial effects on the tested bacteria. The groups that contained poloxamer 407 had nearly identical antibacterial effects on Mutans Streptococci and L. acidophilus. These formulations also inhibited biofilm formation of the bacteria (p<0.05) more effectively. In the positive control group, there was no biofilm formation. CONCLUSIONS: Among the formulations containing poloxamer 407, the one containing Lysozyme and Lactoferrin exhibited the highest inhibitory effect on the tested bacteria. This novel formulation can be beneficial as an antibacterial agent for the prevention of dental caries and biofilm formation.