Table 1.

The blocks tested in the study.

Material	Manufacture	Composition
Vita Enamic	Vita Zahnfabric, Germany	86 % inorganic (58–63 % SiO2, 20–23 % Al2O3, 9–11 % Na2O, 4–6 % K2O, 0.1 % ZrO2) 14 %
Shofu block HC	Shofu inc., Kyoto, Japan	UDMA, TEGMA, 61 wt% silica powder, micro fumed silica, zirconium silicate
Trilor	Bioloren, Saronno, Italy	Epoxy resin matrix (25 % vol), multi directional glass fiber reinforcement (75 % vol)
PEKK	Pekkton Ivory, Cendres + Métaux, Biel/Bienne, Switzerland	Polyetherketoneketone, titanium dioxide pigments