Table 3. Composition, material properties, and application of zirconia66,116.

Composition	3Y-TZP	3Y-TZP	4Y/5Y-TZP	Multilayer
	1 st generation	2 nd generation	3 rd generation	4 th generation
ZrO2 (wt%)	93.4 – 94.5	93.4 – 94.5	89.0 – 92.5	89.0 – 94.5
Y2O3 (wt%)	4.5 – 5.6	4.5 – 5.6	< 10	< 10
Al2O3 (wt%)	0.25 1	0.05	< 0.01	0.05 – 0.01
Other oxides (wt%)	≤ 1.0	≤ 1.0	≤ 1.0	≤ 1.0
Material Properties
Biaxial flexural	1000 – 1500	900 – 1300	400 – 1000	550 – 650
strength (MPa)
KIc (MPa.√m)	5.0	5.0	2.4 – 3.75	2.4 – 5
Translucency parameter (TP)	16 (0.5 mm thickness)	19 (0.5 mm thickness)	32 (0.5 mm thickness)	20 (1.0 mm thickness)
E (GPa)	210	210	210	210
Hardness (GPa)	13.4	12.3	12.9	15
Applications
Anterior		x	x	x
Posterior	x	x		x
Crown	x	x	x	x
Bridge up to 3	x	x		x
Full bridge	x	x
Substructure	x	x
Inlay/onlay			x
Veneer			x	x