Table 5. Masking ability of the zirconia specimens on the opaque porcelain sintered precious-metal substrate.

		Thickness (mm)
		0.7	1.0	1.2	1.5
Shade of zirconia	1M1	Ta < Yb	ta < Yb < Wc < Od	ya < Oa < Tb < Wb	wa < Tb < Yc < Oc,d < Bd
	1M2	ba < Yb < Wc < Oc < Td	oa < bb < yc < Wd < Te	ba < oa < Wb < Yb < Tc	oa < wb < yc < tc < Bd
	2M1	Wa < Yb < Ob < Bc < Td	Wa < Tb < Ob < Yc < Bd	wa < ob < bb,c < tc,d < yd	oa < wb < yc < bd < Te
	2M2	Wa < Ba < Yb < Tb	wa < Ob < Yb < Tc < Bc	oa < yb < tc < Wd < Bd	ya < ob < wb < tb < Bc
	2M3	Ta < Ob < Yc < Bd	Wa < Oa < Ta < Bb < Yc	Ta < Ob < Bb < Wc < Yd	oa < Tb < Bb < Wc < Yd
	3M2	Oa < Wa < Bb < Yc < Tc	Wa < Tb < Bc < Yd < Oe	Ta < Wb < Yc < Bc < Od	wa < yb < tc < bd < od
	4M2	ba <ta,b < wb < yc < od	ta < wa < bc < od < ye	ya < tb < wc < bd < oe	ya < ta < wb < bc < od
	5M2	Ya < Wb < Bc < Tc < Oc	ta < bb < Yb,c < Oc < Wd	ta < ya < ba < wb < Ob	ya < bb < tb,c < oc,d < wd

^*W(w), Y(y), T(t), B(b) and O(o), respectively, represent the ΔE values of different groups using try-in pastes in shades of white, yellow, transparent, bleach and opaque; Capital letters (W, Y, T, B, O) mean 2.6 ≤ ΔE < 5.5; Lowercases (w, y, t, b, o) mean ΔE < 2.6; Same superscripts represent no statistical difference between the groups.