Análise de cimentos à base de silicato de cálcio associado a diferentes radiopacificadores

• Ano de defesa: 2016
• Autor(a) principal: Costa, Bernardo [UNESP]
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Dental materials; Physical and chemical properties; Silicate cement; Materiais dentários; Propriedades físicas e químicas; Cimento de silicato
• Link de acesso: http://hdl.handle.net/11449/144723

The MTA and Portland cement (PC) are calcium silicate cements. Bismuth oxide in the MTA composition may affect physicochemical and biological properties. The ytterbium oxide (Yb2O3) and calcium tungstate CaWO4 amy improve the performance of the material. In Chapter 1, it were evaluated some physicochemical properties, bioactive potential and cytotoxicity of MTA Angelus (MTA), calcium silicate cement (CSC) CSC and 30% ytterbium oxide (CSC / Yb2O3). The setting time initial and final was evaluated with Gilmore needles. Compressive strength was analyzed on a mechanical testing machine. The radiopacity was observed with X-rays of the materials and aluminum scale. solubility and flow tests were conducted based on ISO 6876/2002. The data were submitted to ANOVA and Tukey test (5% significance). Cell viability was assessed by MTT assay and Neutral Red dye, while the mineralization potential were avaluated by alkaline phosphatase activity and alizarin red. The data were submitted to tests One and Two Way ANOVA and Tukey and Bonferroni (5% significance). The bioactive potential was evaluated in scanning electron microscopy. In chapter 2, tricalcium silicate based (TSC) associated with calcium tungstate (CaWO4) and Yb2O3 were evaluated in comparison to the MTA (Angelus, Londrina, Brazil) and pure TSC. The setting time initial and final was evaluated with Gilmore needles. Solubility was assessed after immersion in distilled water. The radiopacity was assessed by radiographs of materials with aluminum scale. The pH was measured by digital pH meter. The bioactivity was assessed by scanning electron microscopy after immersion in PBS. The volumetric change (in mm3 ) was evaluated in cavities filled with experimental materials and scanned in Micro-CT (SkyScan 1176, Bruker, Kontich, Belgium) after 7 and 30 days of immersion in distilled water. The data were submitted to ANOVA and Tukey's test at 5% significance. We concluded that Yb2O3 combined with calcium silicate cement provides adequate radiopacity is citocompatível and presents bioactive potential. Furthermore, the combination of tricalcium silicate cement to CaWO4 and Yb2O3 promotes radiopacity, solubility, alkalinizing ability and low dimensional change suggesting its use as radiopacifier calcium silicate based materials.