Effect of a post-polymerization treatments on the flexural strength and Vickers hardness of reline and acrylic denture base resins

Autor(es)

Rosangela Seiko Seo ^[1] ; Carlos Eduardo Vergani ^[2] ; Eunice Teresinha Giampaolo ^[3] ; Ana Claudia Pavarina ^[4] ; Ana Lucia Machado ^[5]

Afiliação do(s) autor(es)

^[1] University of Várzea Grande. Dental School - Brasil

^[2] São Paulo State University. Dental School of Araraquara. Department of Dental Materials and Prosthodontics - Brasil

^[3] São Paulo State University. Dental School of Araraquara. Department of Dental Materials and Prosthodontics - Brasil

^[4] São Paulo State University. Dental School of Araraquara. Department of Dental Materials and Prosthodontics - Brasil

^[5] São Paulo State University. Dental School of Araraquara. Department of Dental Materials and Prosthodontics - Brasil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Applied Oral Science; v. 15, n. 6, p. 506-511, 2007-12-00.

Resumo

This study evaluated the effect of water-bath and microwave post-polymerization treatments on the flexural strength and Vickers hardness of four autopolymerizing reline resins (Duraliner II-D, Kooliner-K, Tokuso Rebase Fast-TR and Ufi Gel Hard C-UGH) and one heat-polymerized acrylic resin (Lucitone 550-L), processed using two polymerization cycles (short cycle - 90 minutes at 73ºC and 100ºC for 30 minutes; and long cycle - 9 hours at 71ºC). For each material, thirty specimens (64 x 10 x 3.3 mm) were made and divided into 3 groups (n=10). Specimens were tested after: processing (control group); water-bath at 55ºC for 10 minutes (reline materials) or 60 minutes (L); and microwave irradiation. Flexural strength tests were performed at a crosshead speed of 5 mm/min using a three-point bending device with a span of 50 mm. The flexural strengths values were calculated in MPa. One fragment of each specimen was submitted to Vickers hardness test. Data were analyzed by 2-way ANOVA followed by Tukey's HSD test (alpha=0.05). L microwaved specimens (short cycle) exhibited significantly higher flexural strength means than its respective control group (p<0.05). Water-bath promoted a significant increase (p<0.05) in flexural strength of K and L (long cycle). The hardness of the tested materials was not influenced by the post-polymerization treatments. Post-polymerization treatments could be used to improve the flexural strength of some materials tested. (AU)

• Processo FAPESP: 01/01403-4 - Análise da resistência flexural e da dureza de resinas acrílicas para reembasamento do tipo imediato: efeito da complementação térmica de polimerização
• Beneficiário: Rosangela Seiko Seó
• Modalidade de apoio: Bolsas no Brasil - Mestrado