ABSTRACT
Objectives Evaluate the thickness and the marking quality of different occlusal contact registration strips (OCRS) and a possible correlation between them. Material and Methods The following OCRS were selected: Accufilm II, BK20, BK21, BK22, BK23, BK28, and BK31. The thickness was measured in three points of the OCRS with an electronic measuring device (TESA), and the mean was calculated. To produce the marks on the strips, composite resin specimens were adapted to a universal testing machine (Versat 2000) with 40 kgf load cell at a speed of 1.0 mm/min. The mark images were photographed with a stereoscopic microscope (Stemi SV11) and processed and analyzed by the 550-Leica Qwin® analyzer. Results Values (μm) found in the 1st and 2nd thickness measurements were: Accufilm II - 16.4 and 14.2; BK20 - 10.0 and 8.1; BK21 - 9.5 and 8.0; BK22 - 9.7 and 8.7; BK23 - 9.8 and 7.9; BK28 - 12.8 and 10.0; and BK31 - 8.4 and 8.0, respectively. The mean (mm2) values found in the mark areas were: Accufilm II - 0.078; BK20 - 0.035; BK21 - 0.045; BK22 - 0.012; BK23 - 0.022; BK28 - 0.024; and BK31 - 0.024. The results were submitted to the Kruskal-Wallis (p<0.05) and Pearson’s correlation tests. Conclusions Only in the 2nd measurement, the OCRS thickness observed was similar to the value indicated by the manufacturers; the Accufilm II and the BK28 strips showed the better marks; and no correlation was found between the thickness and the marking area. .
Subject(s)
Dental Materials , Dental Occlusion , Jaw Relation Record/instrumentation , Analysis of Variance , Image Processing, Computer-Assisted , Jaw Relation Record/methods , Materials Testing , Reference Values , Statistics, Nonparametric , Surface PropertiesABSTRACT
Objetivo: Este estudo objetivou avaliar a resistência ao cisalhamento da união esmalte/resina/braquete de três materiais adesivos: Transbond XT (3M Unitek) de uso específico em ortodontia, RelyX ARC (3M) e Enforce (Dentsply). Metodologia: Foram utilizados 60 dentes bovinos incluídos em resina acrílica em tubos de PVC. Os espécimes foram divididos em três grupos de 20, de acordo com o material de cimentação utilizado. Os braquetes foram cimentados aos dentes e, após 24 horas, aferida a resistência ao cisalhamento em uma máquina universal de ensaios Versat 2000, com velocidade de 1 mm/min. e célula de carga de 50 kgf. Os resultados obtidos foram submetidos a análise estatística (ANOVA e teste de Tukey). Resultados: Não foi verificada diferença significativa entre os materiais avaliados (P<0,05). Conclusão: Todas as resinas testadas apresentaram adesividade suficiente para resistir às forças durante o tratamento ortodôntico, constituindo alternativa viável para a cimentação de braquetes ortodônticos