The Effect of Curing Modes and Times of Third-Generation Led LCU on the Mechanical Properties of Nanocomposites

Abstract

This study evaluates the effect of curing modes and times on the mechanical properties of nanocomposites. Two nanocomposite resins were investigated: supra-nanohybrid (Estelite Posterior Quick; EP) and nanohybrid (Solare X; SX). They were polymerized with a light-emitting diode light-curing units (LED LCU, Valo) as follows: standard mode for 20s (ST20), high power mode for 12s (HP12), high power mode for 20s (HP20), extra power mode for 6s (XP6), and extra power mode for 20s (XP20). For Vickers microhardness (HV), disc-shaped specimens were fabricated (n=10). For the three-point bending test, bar-shaped specimens were fabricated (n=10). Flexural strength and resilience modulus were calculated. The fractured surfaces and specimen surfaces of composites were observed using scanning electron microscopy. The data were analyzed with repeated measures ANOVA, two-way variance, and Bonferroni tests (p