RESUMO
BACKGROUND: Photodynamic therapy (PDT) has demonstrated promising results in the treatment of several clinical pathologies through the photochemical reaction caused by the combination of a photosensitizer and a light source. The objective of this study was to evaluate the antimicrobial effect of the combination of the photosensitizers (PSs) erythrosine/methylene blue activated by a white halogen light device on Streptococcus mutans biofilm. METHODS: Two separate experiments were conducted, the first using the PSs at the concentration of 100⯵M, and the second 250⯵M. The PSs were tested on S. mutans biofilms cultured for 24â¯h in isolation, in combination, with and without light activation for 2â¯min fractionated in 4 periods of 30â¯s. After treatment, biofilms were diluted and plated on BHI medium and incubated for 24â¯h for colony forming units (CFU) counting. The results (log10) were analyzed with ANOVA followed by Tukey test (pâ¯<â¯0.05). RESULTS: The erythrosine/methylene blue combination activated by white halogen light at 100 and 250⯵M, and erythrosine at 250⯵M, methylene blue at 250⯵M presented significantly reduced cell counts (3.2 log10, 5.3 log10, 4.5 log10, 4.3 log10, respectively) when compared to controls (pâ¯<â¯0.05). CONCLUSION: PDT with the combination of erythrosine/methylene blue demonstrated better results that the PSs in isolation regardless of the concentration. The use of this combination at the concentration of 250⯵M shows promise as an antibacterial treatment for carious lesions and should be further assessed.
Assuntos
Biofilmes/efeitos dos fármacos , Eritrosina/farmacologia , Azul de Metileno/farmacologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Streptococcus mutans/efeitos dos fármacos , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Eritrosina/administração & dosagem , Azul de Metileno/administração & dosagemRESUMO
Polymerization shrinkage of resin composite can compromise the longevity of restorations. To minimize this problem, the monomeric composition of composites have been modified. The objective of this study was to conduct a meta-analysis to assess the clinical behavior of restorations performed with low polymerization shrinkage resin composite in comparison with traditional methacrylates-based resin composite. This systematic review was registered at Prospero data system (CRD42015023940). Studies were searched in the electronic databases PubMed, Web of Science, Scopus, Lilacs and EMBASE according to a predefined search strategy. The inclusion criteria were as follow: (1) randomized controlled clinical trials with at least six months of follow-up; (2) studies investigating composites with monomers designed to reduce polymerization shrinkage; (3) studies conducted with class I or II restorations in the permanent dentition; and (4) studies that assessed at least one of the following criteria: marginal integrity/adaptation, marginal discoloration, recurent caries, retention of composite restorations, and postoperative sensitivity. Two independent reviewers analyzed the articles to determine inclusion and risk of bias. The search conducted in the databases resulted in a total of 14,217 studies. After reviewing the references and citations, 21 articles remained. The longest clinical follow-up time was 60 months. The meta-analysis of the data in the included studies demonstrated that only one variable (marginal adaptation after 12 months) showed statistically significant outcomes, in which methacrylates-based composites presented significantly better results than resin composites containing modified monomers. The good level of the scientific evidence as well as the overall low risk of bias of the included studies indicate that composites with silorane, ormocer or bulk-fill type modified monomers have a clinical performance similar to conventional resin composites.