ABSTRACT
The purpose of the present study was to assess the bond strength of composite resin repairs subjected to different surface treatments and accelerated artificial aging. 192 cylindrical samples (CSs) were prepared and divided into 24 groups (n = 8). Half of the CSs were stored in water for 24 h, and the other half were subjected to C-UV accelerated aging for non-metallic specimens. The treatments were phosphoric acid + silane + adhesive (PSA); phosphoric acid + adhesive (PA); diamond bur + phosphoric acid + silane + adhesive (DPSA); diamond bur + phosphoric acid + adhesive (DPA); air abrasion + phosphoric acid + silane + adhesive (APSA); and air abrasion + phosphoric acid + adhesive (APA). The repair was performed and the specimens were again aged as described above. A control group (n = 8) was established and did not receive any type of aging or surface treatment. The specimens were loaded to failure in shear mode with a crosshead speed of 0.5 mm/min until fracture. Data were analyzed by one-way ANOVA/Tukey's test (p < 0.05). No statistically significant differences were found among DPSA, DPA, APSA, APA, and the control group. The aged PSA and PA achieved low bonding values and were statistically different from the control group, whereas the non-aged PSA and PA presented no statistically significant difference from the control group. Repairs with the proposed surface treatments were viable on both recent and aged restorations; however, phosphoric acid + adhesive alone were effective only on recent restorations.
Subject(s)
Composite Resins/chemistry , Dental Bonding/methods , Dental Restoration Repair/methods , Analysis of Variance , Dental Cements/chemistry , Materials Testing , Phosphoric Acids/chemistry , Shear Strength , Surface Properties , Time FactorsABSTRACT
El objetivo de este trabajo fue el de comparar la resistencia a compresión de tres diferentes marcas de resinas compuestas. Filtek Supreme (3M-ESPE), Charisma (Heraus-Kulzer), y Teric Ceram (Ivoclar-Vivadent), utilizando dos fuentes de fotopolimerización (Optilght,Gnathus y Ultraled (Dabi Atlante). En total fueron confeccionados 48 especímenes divididos en 6 grupos conteniendo 8 muestras cada uno. Para los grupos G1 (Filtek Supreme); G3 (Tetric Ceram) e G5 (Charisma) fue utilizada una lámpara de luz halógena; para los grupos G2 (Filtek Supreme); G4 (Tetric Ceram) e G6 (Charisma) fue utilizada una unidad de fotopolimerización por LEDs. El tiempo de polimerización fue el mismo recomendado por los propios fabricantes. Todas las muestras fueron almacenadas en recipientes plásticos negros herméticamente tapados durante 24 horas. Los ensayos mecánicos de compresión fueron realizados usando una Maquina Universal de Ensayos EMIC DL 2000, con célula de carga de 2000kgf con velocidad de acción de 0,5mm/minuto hasta producir la fractura. Los datos obtenidos fueron analizados usando los tests estadísticos ANOVA/Tukey (p<0,005). Las medias encontradas en MPa fueron: G1 248.37; G 2193.75; G3 222.00; G4 195.87; G5 280.37; G6 205.25. Se observó que las resinas compuestas Filtek Supreme y Charisma polimerizadas por luz halógena presentaron los valores de resistencia a compresión estadísticamente superiores a los mostrados por los grupos polimerizados con LEDs. El grupo de Tetric Ceram no mostró diferencia estadísticamente significante. El grupo 5 mostró valores superiores en relación a los otros grupos, siendo estadísticamente diferente de los grupos 2,3,4,6. El grupo 2 mostró los menores valores, siendo estadísticamente diferente de los grupos 1 y 5. Por los resultados obtenidos puede concluirse de que las resinas fotopolimerizadas por luz halógena presentaron los mejores resultados de resistencia a compresión con excepción de la resina compuesta Tetric Ceram.
This study main purpose was to evaluate the mechanical response of three different resin composite brands; Filtek Supreme, Charisma and Tetric Ceram cured by halogen or light emitting diode - LED (Optilght,Gnathus e Ultraled, Dabi Atlante). A nylon mold 4-mm in diameter and 8-mm in depth was used to obtain forty eight specimens dived in 6 groups of 8 varying the light-curing unit; G1 Filtek Supreme, G3 Tetric, G5 Charisma cured by halogen light-curing unit, and G2 Filtek Supreme, G4 Tetric, G6 Charisma cured by LED. The resin composites were inserted according to the incremental method. The resin composites were light cured according to the manufactures' instructions. The specimens were kept in plastic containers airtightly closed for 24 hours. In order to perform the evaluation, an EMIC DL 2000 was used at a crosshead speed of 0.5 mm/minute and a charge cell of 2000 Kg strength. The statistical analysis was performed using one-way analysis of variance (ANOVA) and Tukey test at a p<0.05 significance level. The mean were G1 248.37, G2 193.75, G3 222.00, G4 195.87, G5 280.37, G6 205.25. In conclusion, the resin composites light-cured by halogen scored higher in the compressive strength test. In the Tetric Ceram group there were no statistically relevant results.