Influence of ethanol concentration on softening tests for cross-link density evaluation of dental composites

• Autor(a) principal: Moraes,Rafael Ratto de
• Data de Publicação: 2007
• Outros Autores: Schneider,Luis Felipe Jochims, Correr-Sobrinho,Lourenço, Consani,Simonides, Sinhoreti,Mário Alexandre Coelho
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Materials research (São Carlos. Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392007000100017
• topic: dental composite; cross-link density; ethanol; softening

This study investigated the influence of ethanol concentration on softening tests for cross-link density evaluation (microhardness) of dental composites. Specimens of Filtek Z100 (3M ESPE) were light-activated by standard or pulse-delay methods. After initial Knoop hardness readings (KHN1), half of specimens (n = 10) for each irradiation method was stored in 100% ethanol, and half in 75% ethanol, during 24 hours, and hardness was determined anew. Hardness deterioration (DKHN) was recorded as the difference between pre and post-storage values. KHN1 data were submitted to one-way ANOVA and Tukey's test (alpha = 0.05), and hardness deterioration was analyzed by two-way ANOVA and Tukey's test (alpha= 0.05). For KHN1, no significant differences were detected between the activation modes (p = 0.697). Samples light-activated by the pulse-delay method presented significantly higher softening compared to the standard mode when samples were immersed in 100% ethanol. Conversely, no significant differences between curing modes were detected for samples stored in 75% ethanol.