ABSTRACT
Objetivo: determinar la tasa de muerte celular al exponer fibroblastos humanos (FBH) a concentraciones de BisGMA: IE-6[M], 6E-5[M], IE-5[M] y 4,8E-4[M], con el fin de determinar la citotoxicidad de BisGMA presente en materiales de uso odontológico. Material y métodos: las concentraciones de BisGMA se aplicaron en el cultivo FBH durante 24, 48 y 96 horas. La viabilidad celular se determinó mediante ensayos de reducción metabólica del Bromuro de 3-(4,5dimetiltiazol-2-ilo)-2,5-difeniltetrazol (MTT). Resultados: las concentraciones de BisGMA generan una disminución en la viabilidad celualr, de una forma dosis y tiempo dependiente. Conclusión: la disminución de la viabilidad celular es dependiente de la concentración de BisGMA presente en los cultivos celulares.
Subject(s)
Humans , Polymethacrylic Acids/toxicity , Fibroblasts , Composite Resins/chemistry , Cell Survival , Materials Testing , Time Factors , Cell Culture Techniques/methodsABSTRACT
This aim of this study was to evaluate the physicochemical and biological properties of novel experimental cements (Hybrid, Paste and Resin) based on synergistic combinations of existing materials, including pH, diametral tensile strength (DTS) and cytotoxicity comparing them with mineral trioxide aggregate (MTA - Angelus®) and a glass ionomer cement (GIC) developed at our laboratory. For the physicochemical and biological tests, specimens with standard dimensions were produced. pH measurements were performed with digital pH meter at the following time intervals: 3, 24, 48 and 72 h. For the DTS test, cylindrical specimens were subjected to compressive load until fracture. The MTT assay was performed for cytotoxicity evaluation. Data were analyzed by ANOVA and Tukey's test (α=0.05). Paste group showed pH values similar to MTA, and Hybrid group presented pH values similar to GIC (p>0.05). The tested materials showed pH values ranging from alkaline to near neutrality at the evaluated times. MTA and GIC showed similar DTS values. The lowest and highest DTS values were seen in the Paste and Resin groups, respectively (p<0.05). Cell viability for MTA and experimental Hybrid, Paste and Resin groups was 49%, 93%, 90% and 86%, respectively, when compared with the control group. The photo-cured experimental resin cement showed similar or superior performance compared with the current commercial or other tested experimental materials.
O objetivo deste estudo foi avaliar propriedades físico-químicas e biológicas de novos cimentos experimentais (Híbrido, Pasta e Resinoso) baseado na combinação sinérgica de materiais existentes, incluindo pH, resistência à tração diametral (RTD) e citotoxidade, comparando-os ao MTA (Angelus®) e a um cimento de ionômero de vidro (CIV) desenvolvido em nosso laboratório. Para a realização dos testes físico-mecânico e biológico, foram confeccionados espécimes com dimensões padrão. O teste de pH foi realizado por meio de pH-metro digital nos tempos: 3, 24, 48 e 72 h. Para o teste de RTD, espécimes cilíndricos foram submetidos a carga compressiva até sua fratura. Para avaliação da citotoxidade, utilizou-se o teste MTT. Os dados foram analisados utilizando ANOVA e teste de Tukey (α=0,05). O grupo Pasta apresentou valores de pH semelhantes ao MTA, assim como o grupo Híbrido seguiu os parâmetros do CIV (p>0,05). Todos os materiais apresentaram valores de pH alcalinos ou próximosà neutralidade nos tempos avaliados. MTA e CIV apresentaram valores de RTD similares. Os menores e maiores valores observados foram do grupo Pasta e Resinoso, respectivamente (p<0,05). A viabilidade celular para os grupos MTA, Híbrido, Pasta, Resinoso, quando comparados ao grupo controle foi de: 49, 93, 90 e 86%, respectivamente. O cimento experimental Resinoso apresentou desempenho similar ou superior aos materiais comerciais e experimentais avaliados.
Subject(s)
Animals , Mice , Dental Cements/chemistry , Pulp Capping and Pulpectomy Agents/chemistry , Aluminum Compounds/chemistry , Aluminum Compounds/toxicity , Biocompatible Materials/chemistry , Bismuth/chemistry , Bismuth/toxicity , Chemical Phenomena , Calcium Compounds/chemistry , Calcium Compounds/toxicity , Cell Survival/drug effects , Composite Resins/chemistry , Composite Resins/toxicity , Drug Combinations , Dental Cements/toxicity , Fibroblasts/drug effects , Glass Ionomer Cements/chemistry , Glass Ionomer Cements/toxicity , Hydrogen-Ion Concentration , Light-Curing of Dental Adhesives , Materials Testing , Methacrylates/chemistry , Methacrylates/toxicity , Oxides/chemistry , Oxides/toxicity , Polyethylene Glycols/chemistry , Polyethylene Glycols/toxicity , Polymethacrylic Acids/chemistry , Polymethacrylic Acids/toxicity , Polyurethanes/chemistry , Polyurethanes/toxicity , Pulp Capping and Pulpectomy Agents/toxicity , Resin Cements/chemistry , Resin Cements/toxicity , Self-Curing of Dental Resins , Stress, Mechanical , Silicates/chemistry , Silicates/toxicity , Tensile Strength , Time FactorsABSTRACT
OBJECTIVE: Applications of resin luting agents and high-power light-emitting diodes (LED) light-curing units (LCUs) have increased considerably over the last few years. However, it is not clear whether the effect of reduced exposure time on cytotoxicity of such products have adequate biocompatibility to meet clinical success. This study aimed at assessing the effect of reduced curing time of five resin luting cements (RLCs) polymerized by high-power LED curing unit on the viability of a cell of L-929 fibroblast cells. MATERIAL AND METHODS: Disc-shaped samples were prepared in polytetrafluoroethylene moulds with cylindrical cavities. The samples were irradiated from the top through the ceramic discs and acetate strips using LED LCU for 20 s (50 percent of the manufacturer's recommended exposure time) and 40 s (100 percent exposure time). After curing, the samples were transferred into a culture medium for 24 h. The eluates were obtained and pipetted onto L-929 fibroblast cultures (3x10(4) per well) and incubated for evaluating after 24 h. Measurements were performed by dimethylthiazol diphenyltetrazolium assay. Statistical significance was determined by two-way ANOVA and two independent samples were compared by t-test. RESULTS: Results showed that eluates of most of the materials polymerized for 20 s (except Rely X Unicem and Illusion) reduced to a higher extent cell viability compared to samples of the same materials polymerized for 40 s. Illusion exhibited the least cytotoxicity for 20 s exposure time compared to the control (culture without samples) followed by Rely X Unicem and Rely X ARC (90.81 percent, 88.90 percent, and 83.11 percent, respectively). For Rely X ARC, Duolink and Lute-It 40 s exposure time was better (t=-1.262 p=0,276; t=-9.399 p=0.001; and t=-20.418 p<0.001, respectively). CONCLUSION: The results of this study suggest that reduction of curing time significantly enhances the cytotoxicity of the studied resin cement materials, therefore compromising their clinical performance.