Avaliação da perda de massa e rugosidade superficial de compômeros após teste de abrasão por escovação simulada

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.O objetivo deste estudo foi avaliar a resistência ao desgaste de compômeros submetidos a um teste escovação simulada. A hipótese nula testada foi que não haveria diferenças em perda de massa e alterações de rugosidade superficial entre os compômeros após o teste. Os materiais empregados foram o Dyract (Dentsply), Dyract AP (Dentsply), Compoglass F (Vivadent), Freedom (SDI), F2000 (3M ESPE), comparados às resinas compostas Z100 (3M ESPE) e Silux Plus (3M ESPE). Para cada material, dez espécimes cilíndricos foram confeccionados com 5 mm de diâmetro e 3 mm de espessura. Para o teste de abrasão, uma máquina com escovas de cerdas macias e uma solução de dentifrício e água deionizada foi utilizada. Foram realizados 100.000 ciclos de escovação simulada. A perda de massa foi verificada através da diferença em porcentagem entre a massa inicial (antes da escovação) e massa final (após a escovação) através de uma balança analítica Sartorius. A alteração de rugosidade superficial foi determinada pela diferença em porcentagem entre as médias de rugosidade inicial e final, após 5 leituras aleatórias por espécime realizado pelo rugosímetro Hommel Tester T 1000 antes e depois do teste de abrasão. A análise estatística (Teste t pareado, ANOVA e Tukey, á=0,05) demonstrou que todos os materiais do estudo apresentaram perda de massa e aumento significante de rugosidade. Todos os compômeros apresentaram maior perda de massa em relação às resinas compostas. Entre os compômeros, Freedom e Dyract AP apresentaram a menor perda de massa. F2000 apresentou a maior alteração de massa sem diferenças estatísticas quando comparado ao Dyract. Quanto à rugosidade superficial, Dyract, Dyract AP, Z100, Compoglass F e Silux Plus se tornaram mais rugosos, porém sem diferenças estatísticas entre si. Freedom apresentou a maior alteração de rugosidade após o teste de escovação simulada

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

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