RESUMO
Introduction: This study aimed to evaluate the dentinal tubule penetration of an endodontic bioceramic sealer, Sealer Plus BC, after three final irrigation protocols. Methods: Thirty distobuccal roots of maxillary molars were selected. Root canal preparation was performed up to an #40.06 instrument (X1 Blue) under 2.5% sodium hypochlorite irrigation. Specimens were randomly divided into three groups (n=10), according to the final irrigation protocol: G-NaOCl (2.5% sodium hypochlorite + PUI), G-SS (0.9% saline solution + PUI) and G-H20 (Deionized water + PUI). After final irrigation protocols, all specimens were irrigated with phosphate buffer solution. Root canal obturation was performed using the single cone technique and Sealer Plus BC, stained with a specific fluorophore. Specimens were transversely sectioned and each root third was evaluated in a confocal scanning laser microscopy. Images obtained were analyzed for sealer penetration in the dentinal tubules. Results: Dentinal tubule penetration of Sealer Plus BC was not observed in any root third, regardless of the final irrigation protocol investigated. Conclusions: Sealer Plus BC dentinal tubule penetration was not observed after none of the protocols tested. Dentinal tubule penetrability of Sealer Plus BC may be related to other factors rather than the final irrigation protocol.
Assuntos
Selantes de Fossas e Fissuras , Selantes de Fossas e Fissuras/uso terapêutico , Cimentos Dentários/uso terapêutico , Hipoclorito de Sódio/uso terapêutico , Soluções Tampão , Bis-Fenol A-Glicidil Metacrilato/análiseRESUMO
The aim of this double-blind randomized study was to evaluate the biocompatibility of resin-modified glass ionomer cements (RMGIC) by means of morphological and immunohistochemical analyses. RMGICs were selected and divided into four groups: Group CK (Crosslink Orthodontic Band Cement); Group RS (Resilience Light Cure Band Cement) Group RMO (RMO Band Cement), Group TP (Transbond Plus Light Cure Band), and Group C (Control-polyethylene). The materials were implanted in rat subcutaneous tissues, randomly selected for this study. After time intervals of 7, 15, and 30 days the tissues were submitted to morphological analysis. In immunohistochemical analysis, the immuno-marking of antibody CD68 was evaluated. The results obtained were statistically analyzed by the Kruskal-Wallis and Dunn tests (p < .05). In the morphological analysis after 7 days, Groups RS, RMO and TP showed more intense inflammatory infiltrate (p = .004) and only Group RMO presented greater intensity of multinucleated giant cells (p = .027). In the immunohistochemical analysis, Groups RMO and RS were observed to present a larger quantity of CD68+ (p = .004) in the time interval of 7 days and only Group RMO presented statistically significant difference for this parameter after 15 days (p = .026). In the time interval of 30 days, Group RMO presented the largest quantity of multinucleated giant cells (p < .004). The RMGICS Crosslink and Transbond Plus provided significantly better tissue biocompatibility than the Resilience and RMO Cements.
Assuntos
Materiais Biocompatíveis/química , Bis-Fenol A-Glicidil Metacrilato/análise , Cimentos Dentários/análise , Cimentos de Resina/química , Animais , Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Materiais Biocompatíveis/análise , Bis-Fenol A-Glicidil Metacrilato/química , Colagem Dentária , Cimentos Dentários/química , Método Duplo-Cego , Células Gigantes/imunologia , Células Gigantes/ultraestrutura , Humanos , Imuno-Histoquímica , Inflamação , Macrófagos/imunologia , Macrófagos/fisiologia , Masculino , Teste de Materiais/métodos , Distribuição Aleatória , Ratos , Ratos Wistar , Cimentos de Resina/análise , Tela Subcutânea/anatomia & histologia , Tela Subcutânea/imunologia , Tela Subcutânea/fisiologiaRESUMO
OBJECTIVES: The aim of this study was to evaluate the degradation of different resin filling materials after a caries challenge, by high performance liquid chromatography (HPLC) and contact angle (θ) measurement. METHODS: Four different polymeric restorative materials (a resin composite, a polyacid-modified resin composite, an ormocer and a resin-modified glass ionomer cement) were tested. Five samples (30 mm × 6 mm × 2 mm) of each material were formed in a Teflon mold, following the manufacturer's instructions. After pH cycles, the solutions were injected in an HPLC. The θ was obtained, before and after pH cycle, by a goniometer at 60% air humidity and 25°C. A distilled water drop (0.006 ml) was put on the material surface, and after 6 min, 10 measures were obtained at 20s intervals. Each sample received 4 drops, one at a time, on different areas. RESULTS: HPLC results showed elution of byproducts in all materials. This was greater in the acid medium. Bis-GMA and TEGDMA were detected in TPH Spectrum and Definite residues. Analyses of the contact angle by ANOVA and Student-Neuman-Keuls's test showed that the surfaces of TPH Spectrum, Dyract AP and Definite were altered, except Vitremer (p<0.05). SIGNIFICANCE: All materials tested degraded on a caries simulated medium, suggesting that a great effort should be made to disseminate oral health information, since a high caries challenge environment (low pH) can lead to dental composite degradation, with potential toxic risks to patients.
Assuntos
Compômeros/metabolismo , Resinas Compostas/metabolismo , Cárie Dentária/metabolismo , Restauração Dentária Permanente/métodos , Biotransformação , Bis-Fenol A-Glicidil Metacrilato/análise , Cromatografia Líquida de Alta Pressão , Compômeros/química , Resinas Compostas/química , Cimentos de Ionômeros de Vidro/química , Cimentos de Ionômeros de Vidro/metabolismo , Concentração de Íons de Hidrogênio , Teste de Materiais , Metacrilatos/análise , Polietilenoglicóis/análise , Ácidos Polimetacrílicos/análise , Poliuretanos/análise , Termogravimetria , MolhabilidadeRESUMO
La introducción de la tecnología de las resinas compuestas dentro de la odontología restauradora, ha sido una de las contribuciones más significativas para la odontología en los últimos veinte años. Las ventajas de las restauraciones adheridas a la estructura dental, incluyen conservación de tejido dental sano, reducción de la microfiltración, prevención de la sensibilidad postoperatoria, refuerzo de la estructura dental y la transmisión / distribución de las fuerzas masticatorias a través de la interfase adhesiva del diente. A pesar de sus ventajas, las resinas compuestas presentan significativas deficiencias en cuanto a su desempeño, sobre todo lo relacionado con la contracción de polimerización y al estrés que esta produce en la interfase diente - restauración. Actualmente, las mejoras en las formulaciones, el desarrollo de nuevas técnicas de colocación y la optimización de sus propiedades físicas y mecánicas, han hecho la restauración de resina compuesta más confiable y predecible. El objetivo principal de este artículo fue analizar los avances en los materiales de restauración de resina compuesta, a través de una exhaustiva revisión de la literatura, donde se valoraron aspectos tales como: composición, clasificación, propiedades físicas y mecánicas, aspectos de manipulación y tendencias actuales de estos materiales
The introduction of composite-based resin technology to restorative dentistry was one of the most significant contributions to dentistry in the last twenty year. The advantages of bonded restorations include conservation of sound tooth structure, reduction of microleakage, prevention of postoperative sensitivity, tooth reinforcement and the transmission / distribution of functional stress across the bonding interface of the tooth. Today, improvements in formulations, development of new placement techniques and the optimization of physical and mechanicals properties had made the direct composite restoration more reliable and predictable. The main objective of this article was analyzing the advances of resin composites restoration material. Trought an exhaustive literature revision. Valuing aspect as composition, classification, phisycal and mechanical properties, manipulation and current trends of this material.
Assuntos
Humanos , Bis-Fenol A-Glicidil Metacrilato/análise , Bis-Fenol A-Glicidil Metacrilato/uso terapêutico , Materiais Dentários/análise , Materiais Dentários/uso terapêutico , Resinas Compostas/análise , Resinas Compostas/uso terapêutico , OdontologiaRESUMO
The effect of different anatomic shapes and materials of posts in the stress distribution on an endodontically treated incisor was evaluated in this work. This study compared three post shapes (tapered, cylindrical and two-stage cylindrical) made of three different materials (stainless steel, titanium and carbon fibre on Bisphenol A-Glycidyl Methacrylate (Bis-GMA) matrix). Two-dimensional stress analysis was performed using the Finite Element Method. A static load of 100N was applied at 45 degrees inclination with respect to the incisor's edge. The stress concentrations did not significantly affect the region adjacent to the alveolar bone crest at the palatine portion of the tooth, regardless of the post shape or material. However, stress concentrations on the post/dentin interface on the palatine side of the tooth root presented significant variations for different post shapes and materials. Post shapes had relatively small impact on the stress concentrations while post materials introduced higher variations on them. Stainless steel posts presented the highest level of stress concentration, followed by titanium and carbon/Bis-GMA posts.