Evaluation of weight loss and surface roughness of compomers after simulated toothbrushing abrasion test

Abstract

This study aimed at analyzing the compomers wear by an "in vitro" toothbrushing abrasion test. The null hypotheses tested were that there would be no differences in weight loss and no significant changes in surface roughness of the compomers after this test. The utilized commercial brands were Dyract (Dentsply), Dyract AP (Dentsply), Compoglass F (Vivadent), Freedom (SDI), F2000 (3M ESPE), which were compared to the two resin composites Z100 (3M ESPE) and Silux Plus (3M ESPE). Ten cylindrical specimens for each commercial brand were prepared with 5mm diameter and 3mm thickness. An appropriate machine with soft bristle tips containing dentifrice solution and deionized water was used. A total of 100,000 brushing cycles were performed. The amount of weight loss was measured by the percentage alteration between the initial (before toothbrushing) and final weight (after toothbrushing), measured by a Sartorius analytical balance. The surface roughness change was determined by the percentage difference between initial and final means after 5 tracings by a T 1000 Hommel Tester roughness meter on the specimen's surfaces before and after toothbrushing abrasion test. The statistical analysis (Students paired t-test, ANOVA and Tukey, á=0.05) showed that all materials presented statistically significant weight loss and roughness increase after abrasion test. All compomers presented higher weight loss than resin composites. Freedom and Dyract AP presented the lowest weight loss among compomers. F2000 presented the worst abrasion resistance, without statistical differences with Dyract. For roughness changes, Dyract, Dyract AP, Z100, Compoglass F and Silux Plus showed the lowest surface roughness alteration, in increasing order, without statistical differences between them. Freedom was the statistically roughest material of the study.

Evaluation of surface physical properties of acrylic resins for provisional prosthesis

“…Several authors 27,28,29,30 have stated the importance of choosing adequate parameters for surface roughness measurements. Because the Ra parameter is limited to horizontal measurements 27,28,29 , different surfaces could present the same roughness values, thus rendering the results questionable.…”

“…Because the Ra parameter is limited to horizontal measurements 27,28,29 , different surfaces could present the same roughness values, thus rendering the results questionable. Nevertheless, since this parameter is a routine method 1,14,15,16,17,30 , it was adopted here to facilitate comparisons with previous studies.…”

Efeito da escovação na formação in situ de biofilme dentário inicial e na rugosidade superficial em cerâmica de y-tzp após vitrificação e polimento

“…Foram simulados no presente estudo 400.000 ciclos, o que corresponde a aproximadamente três anos de escovação (Hossain et al, 2006(Hossain et al, , 2007Wataha et al,1999) e a pressão aplicada de 200g (Amaral et al, 2006;Correr Sobrinho et al, 2001;Garcia et al, 2004;Mondelli et al, 2005;Wang et al, 2004).…”

“…No presente estudo, optou-se por reproduzir, através de uma máquina de escovação, condições semelhantes às que ocorrem in situ, por ser este um método efetivo para avaliar a resistência ao desgaste de materiais restauradores tais como: resinas compostas, cimento de ionômero de vidro, cerâmicas, titânio, ouro, amálgama e resinas acrílicas (Amaral et al, 2006;Heintze;Forjanic, 2005;Hossain et al 2006;Johannsen et al, 1992;Mondelli et al,2005;Yesil Duymus et al, 2006).…”

Avaliação de massa e rugosidade superficial de pastilhas de Ti-6Al-4V com aplicação de nanopartículas de prata submetidos ao teste de escovação

“…A cada 50000 ciclos, os corpos de prova eram removidos da barra e novamente limpos com álcool isopropílico e máquina de ultrassom por mais 20 minutos, sendo pesados por 3 vezes, obtendo-se assim as massas parciais e avaliada suas rugosidades superficiais. Este procedimento foi repetido até alcançado 200.000 ciclos, equivalentes a 10 anos de escovação (MONDELLI et al, 2005).…”