Adição de monômero com função quaternária de amônio em adesivos experimentais para colagem de bráquetes metálicos : desenvolvimento de lesão cariosa e resistência de união após desafio cariogênico

Detalhes bibliográficos
Ano de defesa: 2016
Autor(a) principal: Nascimento, Patrícia Layane de Menezes Macêdo lattes
Orientador(a): Silva, André Luís Faria e
Banca de defesa: Não Informado pela instituição
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal de Sergipe
Programa de Pós-Graduação: Pós-Graduação em Odontologia
Departamento: Não Informado pela instituição
País: Brasil
Palavras-chave em Português:
Palavras-chave em Inglês:
Área do conhecimento CNPq:
Link de acesso: https://ri.ufs.br/handle/riufs/5902
Resumo: Incipient carious lesions manifested by white spots are frequently visualized around the orthodontic brackets. Further to possible progression of these lesions to cavities, a reduction on the bond strength of the bracket to the tooth enamel might occur due to mineral loss. Adhesive systems containing monomers that inhibits the bacteria adhesion or activity have been developed to help at caries control around of brackets. This study evaluated the caries inhibition and shear bond strength reached by addition of antibacterial monomer 2-(Methacryloyloxy)ethyl]trimethylammonium chloride (MADQUAT) to adhesive used to cement orthodontic brackets when submitted to cariogenic challenge. Sound premolars were sectioned in halves and brackets are cemented to the buccal and lingual surfaces using experimental adhesives with 0 (control), 5 or 10% of MADQUAT. Half of the samples was subjected to cariogenic challenge using a microcosm biofilm model with intermittent exposure to sucrose for 6 hours per day during 5 days. Following, the samples were embedded in resin cylinders and brackets submitted to shear loading until the de-bonding. The mode failure was analyzed under optical microscopy. The tested samples were sectioned and the internal enamel hardness measured to calculate the integrated mineral loss (ΔS). Data of bond strength and ΔS were submitted to two-way ANOVA and Tukey test, while the chi-square test was used to assess the effect of factors on failure mode (α = 0.05). The adhesive containing 10% of MADQUAT significantly reduced the demineralization around the bracket, but also reached lowest bond strength values. No effect on the bond strength and ΔS was observed by addition of 5% MADQUAT to adhesive. The cariogenic challenge did not affect the bond strength and the failure mode, which was influenced only by the adhesive. It was concluded that the MADQUAT was only effective to reduce demineralization when added to the adhesive at a concentration of 10%, whereas this concentration also reduced the bond strength.