Effects of P-15 Peptide Coated Hydroxyapatite on Tibial Defect Repair In Vivo in Normal and Osteoporotic Rats

Table 4

3D microarchitectural properties (mean ± SD) in proximal tibial defects osteoporotic rats.

	Bone volume fraction (%)	Bone surface density (mm^−1)	Bone surface-to-volume ratio (mm^−1)	Structure model index (—)	Connectivity density (mm^−3)	Trabecular separation (m)	Degree of anisotropy (—)	Trabecular thickness (m)
Empty
D0 ()	2.6 ± 1.4	1.15 ± 0.57	59.2 ± 13.2	6.5 ± 1.26	22.7 ± 18.8	0.39 ± 0.22	1.14 ± 0.05	0.06 ± 0.02
D7 ()	8.8 ± 3.5	5.38 ± 2.2	81.6 ± 16.4	4.73 ± 0.65	229.7 ± 190.8	0.2 ± 0.03	1.09 ± 0.04	0.05 ± 0.01
D14 ()	22.7 ± 6.4	10.95 ± 2.44	51.6 ± 7.2	2.57 ± 0.64	627 ± 202.5	0.13 ± 0.02	1.09 ± 0.02	0.05 ± 0.01
D21 ()	20 ± 8.7	7.43 ± 3.56	38.3 ± 6.3	2.81 ± 0.71	313.5 ± 263.7	0.18 ± 0.05	1.12 ± 0.04	0.07 ± 0.01
ANOVA	P < 0.001	P < 0.001	P < 0.001	P < 0.001	P < 0.001	P < 0.001	P = 0.001	P = 0.001
Difference between groups	D0 < D7 < D14, D21	D0 < D7, D21 < D14	D21 < D0, D14 < D7	D0 > D7 > D14, D21	D0 < D7, D21 < D14	D14 < D0, D7, D21	D0 > D7, D14	D21 > D7, D14
ABM/P-15
D0 ()	31.5 ± 6.1	8.77 ± 1.38	28.9 ± 2.2	6.33 ± 1.2	365.6 ± 128	0.11 ± 0.01	1.1 ± 0.03	0.13 ± 0.004
D7 ()	31.2 ± 7.2	10.23 ± 1.93	34.9 ± 4.9	5.91 ± 1.21	564 ± 232.9	0.11 ± 0.02	1.08 ± 0.04	0.12 ± 0,01
D14 ()	51.8 ± 5.8	16.38 ± 1.27	32 ± 4.1	1.4 ± 1.04	1348.2 ± 196.2	0.07 ± 0.01	1.08 ± 0.03	0.11 ± 0,01
D21 ()	57 ± 5.9	14.31 ± 1.23	25.3 ± 3.3	0.7 ± 1.25	969.1 ± 146.5	0.07 ± 0.01	1.07 ± 0.03	0.12 ± 0,01
ANOVA	P < 0.001	P < 0.001	P < 0.001	P < 0.001	P < 0.001	P < 0.001	P = 0.296	P < 0.001
Difference between groups	D0, D7 < D14, D21	D0 < D7 < D21 < D14	D21 < D7, D14	D0, D7 > D14, D21	D0, D7 < D21 < D14	D0, D7 > D14, D21	NS	D0 > D7, D14

D0 = day 0, D7 = day 7, D14 = day 14, and D21 = day 21 after surgery. NS = no significance. values < 0.05 are considered significant.