RESUMO
This study evaluated physiochemical proprieties of a calcium hydroxide-based paste (Calen®) combined with a zinc oxide cement at different ratios (1:0.5, 1:0.65, 1:0.8 and 1:1). Materials were compared regarding setting time, pH variation, radiopacity, solubility, dimensional changes, flow and release of chemical elements. Data were analyzed statistically by ANOVA and Tukey's test (α=0.05). Longer setting time and higher dimensional changes and solubility values were exhibited by 1:0.65 and 1:0.5 ratios (p<0.05). The 1:0.5 and 1:0.65 ratios exhibited the highest pH values at all time points. All materials exhibited high radiopacity values. Significant differences were found only between 1:0.5 and 1:1 ratios for calcium and zinc release (p<0.05), whereas the amount of zirconium was similar among all groups (p>0.05). Considering the evaluated proprieties, combinations of Calen® paste with ZO at 1:0.5 and 1:0.65 ratios had the best results as root canal filling materials for use in primary teeth.
Assuntos
Materiais Restauradores do Canal Radicular/química , Dente Decíduo , Humanos , Concentração de Íons de Hidrogênio , Teste de Materiais , Solubilidade , Espectrometria por Raios XRESUMO
Abstract This study evaluated physiochemical proprieties of a calcium hydroxide-based paste (Calen(r)) combined with a zinc oxide cement at different ratios (1:0.5, 1:0.65, 1:0.8 and 1:1). Materials were compared regarding setting time, pH variation, radiopacity, solubility, dimensional changes, flow and release of chemical elements. Data were analyzed statistically by ANOVA and Tukey's test (α=0.05). Longer setting time and higher dimensional changes and solubility values were exhibited by 1:0.65 and 1:0.5 ratios (p<0.05). The 1:0.5 and 1:0.65 ratios exhibited the highest pH values at all time points. All materials exhibited high radiopacity values. Significant differences were found only between 1:0.5 and 1:1 ratios for calcium and zinc release (p<0.05), whereas the amount of zirconium was similar among all groups (p>0.05). Considering the evaluated proprieties, combinations of Calen(r) paste with ZO at 1:0.5 and 1:0.65 ratios had the best results as root canal filling materials for use in primary teeth.
Resumo O objetivo do presente estudo foi avaliar propriedades físico-químicas da pasta à base de hidróxido de cálcio (Calen(r)) combinado com diferentes proporções de óxido de zinco (OZ) (1:0,5 e 1:0,65, 1:0,8 e 1:1) (Calen(r) /OZ). Os materiais foram comparados quanto ao tempo de endurecimento, variação do pH, radiopacidade, solubilidade, alterações dimensionais, escoamento e liberação de elementos químicos. Os dados obtidos foram submetidos à análise de variância (nível de 5% de significância). Maior grau de endurecimento, valores de alterações dimensionais, e solubilidade foram encontrados para Calen(r) /OZ 1:0,65 e 1:0,5. Calen(r) /OZ 1:0,5 e 1:0,65, apresentaram os maiores valores de pH em todos os momentos. Todos os materiais apresentaram valores elevados de radiopacidade com diferenças significativas (p>.05). Foram encontradas diferenças significativas apenas entre Calen(r) /OZ de 1:0,5 e 1:1 na liberação de cálcio e zinco (p< 0,05), enquanto que a quantidade de zircônia foi semelhante entre todos os grupos analisados (p>.05). Em relação às propriedades avaliadas no presente estudo, as combinações de Calen(r) com óxido de zinco nas proporções 1:0,5 e 1:0,65 são mais adequadas como material obturador para os canais radiculares de dentes decíduos.
Assuntos
Humanos , Concentração de Íons de Hidrogênio , Materiais Restauradores do Canal Radicular/química , Dente Decíduo , Teste de Materiais , Solubilidade , Espectrometria por Raios XRESUMO
This study evaluated the stepwise excavation technique in 138 permanent molars with deep carious lesions and incomplete root formation within a 24-month clinical and radiographic follow-up period. In 96.7% of the cases, success was observed (no pain, integrity of restoration margins, absence of radiographic alterations and apexogenesis). The cases of failure (3.3%) were due to the loss of the temporary restoration. In conclusion, the stepwise excavation is a promising technique for permanent teeth with deep carious lesions and incomplete root formation as a minimally invasive approach because it allows the preservation of pulp vitality and occurrence of apexogenesis.
