Table 2.

Nonlinear Regression Fit Parameter Estimates for rhBMP-2 Release

Formulation	Short-term diffusion parameter,, ±SEM (1/min)	Long-term diffusion parameter,, ±SEM (1/min)	R2value of fit
KOS with rhBMP-2	1.43 × 10−3 ± 1.28 × 10−4*,#	1.17 × 10−2 ± 4.46 × 10−4*,#	0.99
70:30 KOS:KTN with rhBMP-2	2.02 × 10−3 ± 2.56 × 10−4*	9.61 × 10−3 ± 8.01 × 10−4*,#	0.98
50:50 KOS:KTN with rhBMP-2	1.90 × 10−3 ± 9.33 × 10−5*	1.08 × 10−2 ± 5.63 × 10−4*,#	0.99
30:70 KOS:KTN with rhBMP-2	1.79 × 10−3 ± 1.63 × 10−4*	1.14 × 10−2 ± 3.37 × 10−4*,#	0.99
KTN with rhBMP-2	3.15 × 10−3 ± 4.89 × 10−4*	9.41 × 10−2 ± 9.93 × 10−3*	0.97
Collagen with rhBMP-2	6.2 × 10−3 ± 5.16 × 10−4#	0.276 ± 0.011#	0.85

Based on model described by Fu and Kao.²³ Owing to geometrical differences where δ is unknown in our system, the short- and long-term diffusion parameters were computed as a lumped parameter.

^*p < 0.05 compared with collagen with rhBMP-2.

^#p < 0.05 compared with KTN with rhBMP-2 as determined by ANOVA with Tukey's test for n = 3.