Fig. 2From: Surface hardness and flexural strength of dual-cured bulk-fill restorative materials after solvent storageDiagram of the “ball-on-three-ball” biaxial flexural test. (a) Frontal view; (b) upper view of the disc specimen placed concentrically on 3 balls. P is the loading ball applied at the center of the specimen at a crosshead speed of 0.5 mm/minBack to article page