ABSTRACT
ABSTRACT The focus of this study was to test the hypothesis that there would be no difference between the biocompatibility of resin-modified glass ionomer cements. Sixty male Wistar rats were selected and divided into four groups: Control Group; Crosslink Group; RMO Group and Transbond Group. The materials were inserted into rat subcutaneous tissue. After time intervals of 7, 15 and 30 days morphological analyses were performed. The histological parameters assessed were: inflammatory infiltrate intensity; reaction of multinucleated giant cells; edema; necrosis; granulation reaction; young fibroblasts and collagenization. The results obtained were statistically analyzed by the Kruskal-Wallis and Dunn test (P<0.05). After 7 days, Groups RMO and Transbond showed intense inflammatory infiltrate (P=0.004), only Group RMO presented greater expression of multinucleated giant cell reaction (P=0.003) compared with the control group. After the time intervals of 15 and 30 days, there was evidence of light/moderate inflammatory infiltrate, lower level of multinucleated giant cell reaction and thicker areas of young fibroblasts in all the groups. The hypothesis was rejected. The Crosslink cement provided good tissue response, since it demonstrated a lower level of inflammatory infiltrate and higher degree of collagenization, while RMO demonstrated the lowest level of biocompatibility.
Subject(s)
Animals , Male , Rats , Biocompatible Materials/pharmacology , Materials Testing , Subcutaneous Tissue/drug effects , Glass Ionomer Cements/pharmacology , Time Factors , Double-Blind Method , Rats, Wistar , Subcutaneous Tissue/pathology , Edema/pathology , Fibroblasts/drug effects , Necrosis/pathologyABSTRACT
O objetivo deste estudo foi avaliar a citotoxicidade de 3 resinas acrílicas (RA) para bases de prótese sendo duas polimerizadas por energia de microondas (Vipi Wave-VW e Nature Cryl-NC) e uma fotoativada (Eclipse-E); e a biocompatibilidade de materiais reembasadores resilientes (MRR), sendo 2 à base de silicone (Ufi Gel P e Sofreliner S), 2 à base de resina acrílica (Durabase Soft e Trusoft) e 2 condicionadores de tecidos (Softone e Coe Comfort) por meio de análises do metabolismo celular, da morfologia celular, do padrão de morte celular, da proliferação celular e da expressão do fator de crescimento TGFß 1, da integrina α5ß1 e de citocinas. A análise das RA foi realizada com células L929; para os MRR, as análises foram realizadas utilizando-se células L929, e/ou HaCaT e/ou RAW 264,7. Os resultados obtidos foram submetidos à análise estatística, realizada ao nível de significância de 5%. Todos os materiais quando testados com eluatos não apresentaram efeitos citotóxicos, e quando testados em contato direto (MTT e azul de alamar) alteraram significativamente a viabilidade celular, tendo sido os menores valores observados para o material NC quando comparado ao E. Para os materiais reembasadores o T, S e C. Maior taxa de necrose e apoptose foram observadas para os eluatos de todos os materiais quando avaliados no período de 24 horas; além disso, foi demonstrado que os materiais avaliados podem desencadear a expressão do TGFß 1, da integrina α5ß1 e de proteínas inflamatórias (fator de necrose tumoral - TNF-α, da citocina IL-1ß e de 5 quimiocinas: CCL2, CCL3, CCL5, CXCL2 e CXCL4). Sendo assim, de acordo com as limitações do presente estudo, pode-se concluir que a resina Nature Cryl resultou em menor viabilidade celular que a resina Eclipse e que os materiais Ufi Gel P e Sofreliner S apresentaram, em geral, melhor bicompatibilidade dentre os materiais reembasadores resilientes avaliados
The aim of this study was to evaluate the cytotoxicity of 3 denture base acrylic resins with different polymerization methods (Eclipse, Vipi Wave and Nature Cryl) and the biocompatibility of soft lining materials, 2 silicone-based (Ufi Gel P and Sofreliner S), 2 acrylic-based (Durabase Soft and Trusoft) and 2 tissue conditioners (Softone and Coe Comfort), by analysing cell metabolism, cell morphology, pattern of cell death, cell proliferation and expression of growth factor TGFß 1, integrin α5ß1 and cytokines. For the acrylic resins, analyses were made with L929 cells, while for the resilient lining materials, analyzes were performed using L929, and/or HaCaT and/or RAW 264.7 cells. Results were statistically analyzed, at a significance level of 5%. The 24 and 48-h eluates from all materials were not cytotoxic to the cells. For the direct contact tests (MTT and Alamar Blue), a significant effect on cell viability was found, with the lowest values observed for materials NC when compared with E and between the reliners Trusoft, Softone and Coe Comfort. For all materials, increased rate of necrosis and apoptosis were observed for the 24 hs eluates. It was also demonstrated that all materials tested can trigger the expression of TGFß 1, α5ß1 integrin and inflammatory proteins (tumor necrosis factor -TNFα, cytokine IL-1ß and 5 chemokines- CCL2, CCL3, CCL5, CXCL2 and CXCL4). Thus, within the limitations of this study, it can be concluded that the denture base acrylic resin Nature Cryl resulted in lower cell viability compared to the Eclipse resin and that the materials Ufi Gel P and Sofreliner S showed better biocompatibility among the soft liner materials evaluated
Subject(s)
Denture Liners , Cytotoxicity, Immunologic , Materials Testing , Acrylic Resins , In Vitro TechniquesABSTRACT
OBJECTIVE: This study evaluated the response of periapical tissues to the endodontic sealer Endométhasone in root canal fillings short of or beyond the apical foramen. MATERIAL AND METHODS: Twenty root canals of premolars and incisors of 2 mongrel dogs were used. After coronal access and pulp extirpation, the canals were instrumented up to a size 55 K-file and the apical cemental barrier was penetrated with a size 15 K-file to obtain a main apical foramen, which was widened to a size 25 K-file. The canals were irrigated with saline at each change of file. The root canals were obturated either short of or beyond the apical foramen by the lateral condensation of gutta-percha and Endométhasone, originating 2 experimental groups: G1: Endométhasone/short of the apical foramen; G2: Endométhasone/beyond the apical foramen. The animals were killed by anesthetic overdose 90 days after endodontic treatment. The individual roots were obtained and serial histological sections were prepared for histomorphological analysis (H&E and Brown & Brenn techniques) under light microscopy. The following parameters were examined: closure of the apical foramen of the main root canal and apical opening of accessory canals, apical cementum resorption, intensity of the inflammatory infiltrate, presence of giant cells and thickness and organization of the apical periodontal ligament. Each parameter was scored 1 to 4, 1 being the best result and 4 the worst. Data were analyzed statistically by the Wilcoxon nonparametric tests (p=0.05). RESULTS: Comparing the 2 groups, the best result (p<0.05) was obtained with root canal filling with Endométhasone short of the apical foramen but a chronic inflammatory infiltrate was present in all specimens. CONCLUSIONS: Limiting the filling material to the root canal space apically is important to determine the best treatment outcome when Endométhasone is used as sealer.