Mechanical and bonding properties of different combinations of nanohybrid and bulk-fill composites / Propiedades mecánicas y adhesión entre diferentes combinaciones composite Nanohíbrido-Bulkfill

ABSTRACT

ABSTRACT The aim of this research was to determine compressive and shear bond strength of blocks prepared with bulk-fill and nanofill composite resin combinations. Materials used were Filtek Bulk Fill (FBF) and Z350 (both 3M-ESPE) and Surefil SDR flow (SFF) - Dentsply. To determine shear bond strength, cylindrical specimens 10 mm thick were prepared with composite consisting of thicknesses of 6 mm of one material and 4 mm of the other, in the following combinations: G1: FBF- FBF; G2: Z350-Z350, G3: FBF-Z350, G4: Z350-SFF and G5: SFFSFF. Materials were cured using a 1100 mw/cm2 light for 20 seconds for each layer. Samples were stored for 24 hours at 37 °C in distilled water and shear bond strength was determined. To assess compressive strength, cylindrical samples 4 mm diameter and 6 mm thick consisting of 4 mm + 2 mm were used in the same combinations as described above, stored in distilled water at 37 °C for 24 hours, after which compressive strength was determined. Both tests were performed with a Universal testing machine at a cross head speed of 1 mm/min. Results were analyzed with ANOVA and Tukey's test. Means and standard deviations in MPa for each group were the following: Shear bond strength: G1: 435.87 (65.86), G2: 233.6 (108.15), G3: 279.2 (22.05), G4:449.1 (109.35) and G5: 196.6 (51.16). Compressive strength: G1:160.07(4.27), G2: 149.49 (14.06), G3: 156.10 (29.99), G4: 199-30(39.28), G5: 171.23 (28.71). Evaluation with ANOVA showed no significant differences among combinations for compressive strength (p>0.05) and significant differences for bond strength (p<0.05). Tukey's test showed three homogeneous groups. Under these experimental conditions, it can be concluded that the study combinations have adequate mechanical behavior, equivalent to materials used individually. However, shear bond strength was affected by the combinations analyzed.

RESUMEN

RESUMEN El objetivo de este trabajo fue determinar la resistencia compresiva (RC) y la resistencia adhesiva al corte (RAC) en bloques preparados con combinaciones de composites bulk-fill y nanoparticulados. Los materiales usados fueron Filtek Bulk Fill (FBF) y Z350 (ambos de 3M-ESPE) y Surefil SDR flow (SFF) - Dentsply. Para medir la RAC, se prepararon probetas cilindricas de 10 mm de espesor consistentes en 6 mm de un material y 4 mm del otro con las siguientes combinaciones: G1: FBF- FBF; G2: Z350-Z350, G3: FBF-Z350, G4: Z350-SFF y G5: SFF-SFF. Se curaron a 1100 mw/cm2 durante 20 segundos cada capa. Se conservaron 24 horas a 37 °C en agua destilada antes de determinar la RAC. Para medir la RC se prepararon probetas de 4 mm de diametro y 6 mm de espesor (4 mm + 2 mm de cada material), con las mismas combinaciones. Se conservaron en agua destilada a 37 °C durante 24 horas y se midió la RC. Ambos ensayos se realizaron con una máquina universal para ensayos mecánicos a 1 mm/min de velocidad de desplazamiento de cabezal. Los resultados se evaluaron con ANOVA y prueba de Tukey. Las medias y desviaciones estándar (MPa) para cada grupo fueron: RAC: G1: 435.87 (65.86), G2: 233.6 (108.15), G3: 279.2 (22.05), G4:449.1 (109.35) y G5: 196.6 (51.16). RC: G1:160.07(4.27), G2: 149.49 (14.06), G3: 156.10 (29.99), G4: 199-30(39.28), G5: 171.23 (28.71). ANOVA no mostró diferencias estadísticamente significativas para RC (p>0.05) y diferencias significativas para RAC (p<0.05). La prueba de Tukey mostró tres grupos homogéneos. En las condiciones experimentales de este trabajo puede concluirse que las combinaciones evaluadas tienen un comportamiento mecánico adecuado equivalente al de los materiales individuales. Sin embargo, la adhesión entre materiales se vio afectada por las combinaciones realizadas.