Novas terapias no controle de biofilmes orais

Abstract

Biofilms are related to most diseases and antimicrobial agents can be used as alternative treatments to mechanical removal of biofilms. Faced with the emergence of microbial resistance versus the use of conventional antimicrobials, interest in therapies that make the emergence of resistance unlikely has increased. In this context, antimicrobial photodynamic therapy and the use of low temperature plasmas, both based on the formation of reactive oxygen species, can be used. Thus, the objective of this study was to analyze the use of new therapies in the control of oral biofilms. In Chapter 1, an experiment was carried out with a phototherapy on the biofilm formation of Candida albicans (SN 425). The biofilm was exposed to blue or red light (400-690 nm), without the use of photosensitizers, twice a day. Chlorhexidine 0.12% and NaCl (0.89%) were used as control groups. Biofilm samples were analyzed by counting the colony forming units (CFU), dry weight and polysaccharides. A dry weight analysis of the biofilm product of C. albicans revealed a significant reduction after treatment with blue and red light when compared to the control groups. Although it has not been accompanied by the reduction in viability of the cells and considering the growth of this microorganism in the form of hyphae, it was concluded that the treatment twice a day with blue and red light it is a promise therapy for inhibition of C. albicans biofilms. In the second chapter, a low-temperature plasma experiment was performed with volunteers using intraoral devices containing blocks of bovine enamel, treated 10 times daily with a solution of 10% sucrose for 7 days. After the experimental period, the enamel blocks were treated for 5 minutes of plasma, Chlorhexidine 0.12%, argon gas or 0.89% saline solution. The biofilm samples were collected and processed for identification of the genes of the bacteria of interest. The results demonstrated that treatment of plasma biofilms significantly reduced concentrations of Streptococcus mutans, Lactobacillus acidophillus, Streptococcus mitis, Actinomyces naeslundi and Bifidobacterium group (p <0.05) compared to other treatment groups. As concentrations of Lactobacillus casei and Streptococcus gordonii were not influenced by treatment with low temperature plasma. This study provides results for a better understanding between the difference of microbiotes after different antimicrobial treatments in biofilms. In conclusion, the use of low temperature plasmas and photodynamic therapy are effective therapies in inactivation of bacteria and/or in the development inhibition of pathogenic oral biofilms associated with various diseases that generate the oral cavity of humans.