An In Vitro Investigation of Vickers Hardness of A Single-Shade Composite Resin

Aim: This study aimed to investigate the hardness of a single-shade composite resin using two different light-curing procedures compared with a multi-shade composite resin. Material and Methods: In this study, a single-shade (Zenchroma) and a multi-shade (Estelite Sigma Quick) composite resin were used. Two different light-curing procedures (Woodpecker X Cure LED curing device (high mode-3s and soft mode-20s)) were applied as disc-shaped (5 mm in diameter and 2 mm in thickness) samples were prepared from each composite resin. Four different test groups were established with a total of 32 samples (n = 8). Vickers surface hardness measurements and SEM/EDS analyses were carried out. Data was analyzed utilizing two-way analysis of variance, and the significance level was determined as p<0.05. Results: Material and light-curing procedure main effects significantly affected hardness values (p<0.001). The highest hardness value was observed in Zenchroma-soft mode, whereas the lowest hardness value was observed in Estelite Sigma Quick-high mode. Conclusion: Single-shade composite resin exhibited higher hardness values than multi-shade composite resin. Soft mode-20 second light-curing procedure increased single-shade and multi-shade composite resins’ hardness values.