ABSTRACT
Objective: This study analyzed the effect of two light emitting diodes (LEDs) on the degree of conversion (DC) of a composite resin for bleached teeth under the influence of adhesive systems used as modeling liquid. Material and Methods: A total of 60 samples of IPS Empress Direct resin (Ivoclar, Vivadent) in BL-L shade were made in a single increment and polymerized for 20 seconds. The treatments were: 1) Type of adhesive used as modeling liquid (Adper Single Bond 2; the bond component of Adper Scotchbond Multi-Purpose; or no adhesive systems used as modeling liquid were used in the control group); and 2) Type of LED (Bluephase, polywave; and Coltolux, monowave). The DC, percentage of monomers converted to polymer during polymerization, was evaluated using Fourier Transform Infrared Spectroscopy (FTIR) with 10 scans and wavenumber related to 1/λ for observation of the peaks at 1608 and 1638 cm-1. Data were statistically analyzed by two-way analysis of variance (ANOVA) with Tukey's test (p < 0.05). Results: There was no statistical difference between LEDs in comparison to the treatments (p > 0.05). However, there was a statistically significant increase in the DC for the adhesive systems tested in comparison to the control group (p < 0.05), with the highest values for Single Bond 2. Conclusion: It is concluded that the use of adhesives as modeling liquid of Empress Direct resin for bleached teeth shade increases the degree of conversion of the composite surface, and that curing with both kinds of LEDs does not interfere in this property (AU)
Objetivo: Esse estudo analisou o efeito de dois diodos emissores de luz (LEDs) no grau de conversão (GC) de uma resina composta para dentes clareados sob a influência de sistemas adesivos usados como líquido modelador. Material e Métodos: Um total de 60 amostras da resina IPS Empress Direct (Ivoclar, Vivadent) na cor BL-L foram feitas em incremento único e polimerizadas por 20 segundos. Os tratamentos foram: 1) Tipo de adesivo usado como líquido modelador (Adper Single Bond 2; o componente "bond" do Adper Scotchbond Multi-Purpose; ou nenhum dos sistemas adesivos usados como líquido modelador foram utilizados no grupo controle); e 2) Tipo de LED (Bluephase, polifásico; e Coltolux, monofásico). O GC, percentual de monômeros convertidos em polímero durante a polimerização, foi avaliado usando Espectroscopia de Infravermelho com Transformada de Fourier (FTIR) com 10 varreduras e número de ondas relacionado de 1/λ para a observação dos picos de 1608 e 1638 cm-1. Os dados foram analisados estatisticamente por análise de variância (ANOVA) a dois fatores com pós-teste de Tukey (p < 0,05). Resultados: Não houve diferença estatística entre os LEDs na comparação para os tratamentos (p > 0,05). Entretanto, houve um aumento estatisticamente significativo no GC para os sistemas adesivos testados em comparação com o grupo controle (p < 0,05), com os maiores valores para o Single Bond 2. Conclusão: Conclui-se que o uso de adesivos como líquido modelador da resina Empress Direct para dentes clareados aumenta o grau de conversão de superfície dos compósitos e que a fotoativação com ambos os tipos de LEDs não interfere nessa propriedade (AU)
Subject(s)
Biomedical and Dental Materials , Composite Resins , Dentin-Bonding Agents , Spectroscopy, Fourier Transform Infrared , Surface PropertiesABSTRACT
The tackiness presented by resins causes problems in performing the incremental technique, which can be improved by using lubricants in handling. Aim: To evaluate the influence of two adhesive systems as brush lubricants on the degree of conversion, translucency and intrinsic color stability of composite resins. Methods: Samples (n=10) were fabricated according to the composites (Filtek Z350 XT, IPS Empress Direct, and Esthet X HD), shades (bleach shade and A2), and lubricants used (Adper Single Bond 2, Adper Scotchbond Multi-Purpose bonding agent, and no lubricant). Single composite increments were inserted into a Teflon mold. The composite surface was then modeled using a brush dipped in an adhesive system. The control group was fabricated with no additional modeling. The surface degree of conversion (DC) was measured using Fourier transform infrared spectroscopy; translucency and intrinsic color stability were accessed using a spectrophotometer. Data were analyzed using three-way ANOVA and the Tukey test (p<0.05). Results: Scotchbond Multi-Purpose decreased the DC of all composites and shades in comparison with the control group (p<0.05), although it did not decrease color stability (p<0.05). The bleach shade of IPS Empress Direct and Esthet X HD showed higher translucency than the A2 shade when lubricated with the adhesive systems (p<0.05). Conclusion: Therefore, the two tested adhesive systems used as brush lubricants on composites promoted changes to the surface degree of conversion and aesthetic properties