Table 5

Variable	S group	M group	GM group	S vs. M	S vs. GM	M vs. GM
Variable	Mean (SD) in mm			P-value
Socket type 1
ΔHVC	-1.08 (0.71)	-0.52 (0.64)	-0.49 (0.26)	< 0.0001^a	< 0.0001^a	0.0561^b
ΔHLC	-0.92 (0.48)	-0.43 (0.28)	-0.41 (0.59)	< 0.0001^a	< 0.0001^a	0.0542^b
ΔRW	-2.41 (0.58)	-0.31 (0.35)	-0.27 (0.47)	< 0.0001^a	< 0.0001^a	0.0748^b
Socket type 2
ΔHVC	-1.56 (0.39)	-0.69 (0.27)	-0.42 (0.73)	< 0.0001^a	< 0.0001^a	< 0.0001^a
ΔHLC	-1.67 (0.72)	-0.52 (0.69)	-0.37 (0.81)	< 0.0001^a	< 0.0001^a	< 0.0001^a
ΔRW	-2.97 (0.61)	-1.16 (0.25)	-0.88 (0.53)	< 0.0001^a	< 0.0001^a	< 0.0001^a
Socket type 3
ΔHVC	-3.08 (0.71)	-2.51 (0.19)	-1.36 (0.27)	0.0179^b	< 0.0001^a	< 0.0001^a
ΔHLC	-2.92 (0.48)	-2.39 (0.78)	-1.18 (0.51)	0.0124^b	< 0.0001^a	< 0.0001^a
ΔRW	-4.41 (0.58)	-3.94 (0.26)	-2.73 (0.54)	0.0209^b	< 0.0001^a	< 0.0001^a

^aStatistically significant at P ≤ 0.05 (Kruskal-Wallis test).
^bStatistically significant at P > 0.05 (Kruskal-Wallis test).
SD = standard deviation; ΔRW = changes in ridge width, ΔHVC = changes in height of the vestibular crest, ΔHLC = changes in height of the lingual crest; S = spontaneous healing; M = porcine-derived collagen membrane alone; GM = porcine-derived graft material associated with collagen membrane.