RESUMO
OBJETIVO: El objetivo de este estudio fue comparar el grado de conversión (GC) de cuatro cementos resinosos fotoactivados a través de un disco de disilicato de litio medido en dos tiempos: inicial y a las 24 horas. MATERIALES Y MÉTODOS: Se confeccionaron cinco especímenes para cada cemento evaluado : RelyXTM Veneer (RX), ChoiceTM2 (CH), NX3 NexusTM Light cure (NX) y Allcem Veneer (AC), los que fueron analizados con el Espectroscopio infrarrojo FTIR (Fourier Transmission Infrared Spectroscopy) para evaluar el GC inicial y luego almacenados durante 24 horas a 37º C realizándose una segunda medida. Todos los cementos evaluados fueron fotoactivados a través del test de ANOVA de un factor y el de comparaciones múltiples de Tukey. RESULTADOS: Se obtuvieron los siguientes resultados tanto para el GC inicial y a las 24 horas: RX (grupo control) 67.05 ± 0.22% y 76.87 ± 2.57%; CH 70.06 ± 1.52% y 84.80 ± 0.40%; NX 69.01 ± 0.52% y 81.62 ± 0.23%; AC 73,31 ± 0.40% y 85,22 ± 0.07%. Se encontraron diferencias estadísticamente significativas entre los grupos independientes y relacionados. CONCLUSIÓN: El cemento resinoso Allcem Veneer presenta un mejor GC comparado con las otras marcas. Todos los cementos aumentaron su GC significativamente a las 24 horas. (AU)
OBJECTIVE: The aim of this study was to compare the degree of conversion (DC) of four dental resin cements photoactivated through a lithium disilicate disk measured in two stages: initial and 24 hours. MATERIALS AND METHODS: Five especimens for each resin cement (RelyXTM Venner (RX), ChoiceTM 2 (CH), NX3 Nexus TM Light cure (NX) and Allcem Veneer (AC) were fabricated, which were analyzed by infrared spectroscopy FTIR (Fourier Transmission Infrared spectroscopy) to assess the initial DC and then stored for 24 hours at 37ºC performing a second measurement. All cements were photoactivated through a 1.5 mm thick lithium disilicate disk. ANOVA and Tukeys multiple comparison statistical test was performed. RESULTS: The following results were obtained for both the initial DC and 24 hours: RelyX Veneer (control group) 67.05 ± 0.22% y 76.87 ± 2.57%; Choice 2 70.06 ± 1.52% y 84.80 ± 0.40%; NX 3 96.01 ± 0.52% y 81.62 ± 0.23; Allcem Veneer 73,31 ± 0.40% y 85,22 ± 0.07%. Statistically significant differences were found between groups independent and connected. CONCLUSION: The resin cement Allcem Veneer has a better DC compared to other brands. All cements increased their DC significantly at 24 hours. (AU)