Concentração de flúor no esmalte adjacente a diferentes materiais restauradores diretos após desafio cariogênico
Fluoride concentration on enamel adjacent to different direct restorative materials after in vitro cariogenic challenge with Streptococcus mutans
Paradella, T.C.; Koga Ito, C.Y.; Jorge, A.O.C.
Rev. odontol. UNESP, vol.37, n3, p.291-296, 2008
Resumo
O objetivo deste estudo foi avaliar a concentração de flúor no esmalte dentário humano adjacente a diferentes materiais restauradores após desafio cariogênico in vitro com Streptococcus mutans. Para isso, 72 terceiros molares humanos, recém-extraídos receberam preparos classe V padronizados e foram restaurados conforme os grupos: RC-Z: resina composta convencional Z250; RC-F: resina composta modificada por poliácidos Freedom; CIV-V: ionômero de vidro modificado por resina Vitremer: CIV-F: cimento de ionômero de vidro convencional Fuji IX. Foram cortados espécimes de 4 x 4 x 2 mm e subdivididos em Grupo controle (n = 6 mantidos em umidade relativa 100% a 37 °C durante todo o experimento) e Grupo experimental (n = 12). No Grupo experimental, os espécimes foram submetidos ao desafio cariogênico com cultura de S. mutans ATCC 35688 em caldo contendo sacarose a 5%, sendo este caldo substituído a cada 48 horas. Após 14 dias, os espécimes foram imersos em solução remineralizante por 14 dias, sendo então desidratados, metalizados e submetidos à espectroscopia por dispersão de raio X (EDS). Os resultados foram submetidos à análise estatística Kruskall-Wallis e Student-Newman-Keuls (α = 5%) e demonstraram que somente RC-Z apresentou diferença entre o Grupo controle e experimental (p = 0,0037). No Grupo experimental, houve diferença entre RC-Z e RC-F (p = 0,0450), RC-Z e CIV-V (p = 0,0107); RC-Z e CIV-F (p < 0,0001), demonstrando que a concentração de flúor no esmalte adjacente a CIV-V e CIV-F foi superior a dos materiais resinosos, que não apresentaram alta concentração de flúor no esmalte após desafio cariogênico, em comparação aos outros materiais.
Palavras-chave
Streptococcus mutans, cárie, esmalte, flúor
Abstract
The purpose of this study was to evaluate the concentration of fluoride on human tooth enamel adjacent to different direct restorative materials after in vitro cariogenic challenge with Streptococcus mutans. For that, 72 freshly-extracted human third molars received standard class V preps and were restored according to the groups: RC-Z: Z250 conventional composite resin; RC-F: Freedom polyacid-modified composite resin; CIV-V: Vitremer resin-modified glass-ionomer: CIV-F: Fuji IX conventional glass-ionomer cement. Specimens of 4 x 4 x 2 mm were cut and subdivided into control Group (n = 6 kept in 100% relative humidity at 37 °C during all the experiment) and experimental Group (n = 12). In the experimental Group, specimens were submitted to cariogenic challenge with S. mutans ATCC 35688 in 5% sucrose broth, being this broth replaced every 48 hours. After 14 days, specimens were immersed in remineralizing solution for 14 days, being then dehydrated, gold-sputtered and submitted to X-ray diffraction spectroscopy. Results were statistically analyzed by Kruskall-Wallis and Student-Newman-Keuls (α = 5%) tests and showed that only Group RC-Z presented difference between control and experimental Group (p = 0.0037). In the experimental Group, there were differences between RC-Z and RC-F (p = 0.0450), RC-Z and CIV-V (p = 0.0107); RC-Z and CIV-F (p < 0.0001), showing that the fluoride concentration on enamel adjacent to CIV-V and CIV-F was higher than the resinous materials, which did not present high fluoride concentration on enamel after cariogenic challenge, in comparison to the other materials
Keywords
Streptococcus mutans, caries, enamel, fluoride
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