In vitro evaluation of the biocompatibility of new formulations containing lysozyme, lactoferrin and drug delivery system poloxamer 407

In children that under three years old are not suggested to use fluoridated toothpaste because of the risk of fluorosis in developing permanent teeth or chlorhexidine for a long period resulting adverse effects and cytotoxicity. New formulations containing saliva proteins such as lysozyme and lactoferrin might be effective on preventing tooth decay in younger children. Topical application of antimicrobial agents with the drug delivery system poloxamer is thought to be effective in the treatment of oral diseases. Therefore, formulations containing lysozyme, lactoferrin and drug delivery system poloxamer 407 with the trade name of Pluronic F-127 were produced and it has been proven that these formulations are effective on cariogenic bacteria such as Streptococcus sobrinus, Streptococcus mutans and Lactobacillus acidophilus. The aim of this study was to determine the biocompatibility of these new formulations in comparison with 0.2 % chlorhexidine in vitro conditions. Formulations for our study were prepared and divided into seven different groups as follows: (1) Sorensen's solution (pH: 5.0) as buffer, (2) %20 gel formulation containing only poloxamer 407, (3) %10 gel formulation containing only poloxamer 407, (4) Lysozyme and Lactoferrin with %20 concentration of poloxamer 407, (5) Lysozyme and Lactoferrin with %10 concentration of poloxamer 407 as MIC value of group 4, (6) Sorensen's Solution (pH:7.0) as negative control group and (7) dissolved Lysozyme and Lactoferrin in buffer (Sorensen's Solution pH:5.0). %0.2 chlorhexidine mouthwash was used as the control group. In mucosal irritation study, irritation levels of formulations were identified using HET-CAM test method on eggs containing chicken embriyos. In the cytotoxicity test, the MTT test method was used on L 929 cell culture in order to access the cytotoxic effects of the formulations. Mucosal irritation test was performed as two different experiments. Both test groups showed low and moderate irritation levels, none of them showed serious irritation levels. There was no statistical significance between the chlorhexidine control group and other groups. The cytotoxicitiy experiment (MTT), chlorhexidine mouthwash showed lowest cell viability rates. Sorensen's Solution pH:7.0 group showed lowest cytotoxicitiy and highest biocompatibility levels. There is no statistical significance between other groups. In this study, none of the experimental groups showed severe cytotoxicitiy or mucosal irritation. However, more in vitro studies should be carried out to test these materials' kinetic efficiency and also animal studies should be conducted. Keywords: Lysozyme, Lactoferrin, Poloxamer 407, HET-CAM, cytotoxicitiy