Terapia fotodinâmica e plasma de baixa temperatura e pressão como tratamentos alternativos contra biofilmes endodônticos patogênicos

• Ano de defesa: 2015
• Autor(a) principal: Dantas, Thereza Cristina Farias Botelho
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Fotoquimioterapia; Desinfecção; Enterococcus faecalis
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/15302

Photodynamic Antimicrobial Therapy (PACT) and Low Pressure Cold Plasma emerged as an effective adjunctive procedure to conventional endodontic treatment, especially in case of persistent infection. This study was divided into four chapters, which objectives were: Chapter 1) investigate the antibacterial effects of photodynamic antimicrobial chemotherapy (PACT), with different concentrations of toluidine blue-O (TBO), at three different exposure times, over suspensions of Enterococcus faecalis, using a fluorescence probe – Dihydrorhodamine 1, 2,3 for detecting the release of ROS. Chapter 2) study the antimicrobial effect of PACT mediated by Toluidine blue-O activated by red light (LumaCare® LC122) on Enterococcus faecalis and Candida albicans biofilms. Chapter 3) a tissue-tolerable-plasma (TTP) was tested for its antimicrobial activity against mature biofilm of a key endodontic bacterium Enterococcus faecalis. Chapter 4) evaluate the anti-biofilm efficacy of PACT and TTP applied on saliva-coated-teeth with 2-week E. faecalis (ATCC 29212) biofilm, treated with PACT and TTP for 3 different exposure times (1, 2 and 5 minutes) and compared with 2.5% NaOCl irrigation for 5 minutes. In chapters 2 and 3 biofilms were formed on saliva-coated hydroxyapatite discs using batch culture method at 37°C, 5% CO2. BHI broth was changed daily. In chapter 2, mature E. faecalis and C. albicans biofilms were subjected to PACT using TBO (100 μg/mL), using a non-coherent red light source (LumaCare®, 630 nm, 2 mm distance) and energy density of 118.9 J/cm2, 237.8 J/cm2 and 594.5 J/cm2 (chapter 2). Using the same growth conditions, mature E. faecalis biofilms were subject to TTP on chapter 3. The results were expressed by counting colony forming units (cfu) and group means were compared using 1-way ANOVA. The anti-biofilm effect of PACT and TTP improved as exposure time was increased, reaching the maximum effect after 5 minutes of treatment for both therapies. After 5 min of exposure, there is a significant reduction in cfu numbers in PACT and TTP treatments (p<0.05), but neither treatment was as effective as 2.5% NaOCl irrigation. Using root canals in vitro model (chapter 4) TTP was better than PACT, at 5 minutes of exposure. Bacterial killing was confirmed by CLSM/COMSTAT and SEM analysis