Biofilm is a community of bacteria, less susceptible to traditions treatments. Although photodynamic therapy （PDT） is a very effective way to microorganism inactivation, in biofilm it is not as efficient as it is in...Biofilm is a community of bacteria, less susceptible to traditions treatments. Although photodynamic therapy （PDT） is a very effective way to microorganism inactivation, in biofilm it is not as efficient as it is in planktonic bacteria cultures. The increment of an element to increase the effectiveness of PDT was our aim. Therefore, this in vitro study evaluates the susceptibility ofa biofilm formed by Streptococcus mutans on metallic surface of orthodontic accessories under the application of PDT with a surfactant. Samples obtained from blades of orthodontic bands （NiCr）, where used as adhesion surface for the biofilm. They were treated with 1 mg/ml of curcumin, with 0.1% of sodium dodecyl sulfate and exposed to 30 J/cm^2 of light （455 nm）. Eight experimental groups were studied, including the positive and negative controls. The results show that the group with PDT and surfactant had a significant decrease （p 〈 0.001） in viability. In this case, the reduction observed was of 5.6 log10 （CFU/ml） in comparison to the control group. We have shown that, even though the biofilm is very tough and complex structure, we are able to promote almost the complete inactivation ofS. mutans in systems similar to an orthodontic treated patient＇s mouth.展开更多
文摘Biofilm is a community of bacteria, less susceptible to traditions treatments. Although photodynamic therapy （PDT） is a very effective way to microorganism inactivation, in biofilm it is not as efficient as it is in planktonic bacteria cultures. The increment of an element to increase the effectiveness of PDT was our aim. Therefore, this in vitro study evaluates the susceptibility ofa biofilm formed by Streptococcus mutans on metallic surface of orthodontic accessories under the application of PDT with a surfactant. Samples obtained from blades of orthodontic bands （NiCr）, where used as adhesion surface for the biofilm. They were treated with 1 mg/ml of curcumin, with 0.1% of sodium dodecyl sulfate and exposed to 30 J/cm^2 of light （455 nm）. Eight experimental groups were studied, including the positive and negative controls. The results show that the group with PDT and surfactant had a significant decrease （p 〈 0.001） in viability. In this case, the reduction observed was of 5.6 log10 （CFU/ml） in comparison to the control group. We have shown that, even though the biofilm is very tough and complex structure, we are able to promote almost the complete inactivation ofS. mutans in systems similar to an orthodontic treated patient＇s mouth.
