Figure 3

Gross observations of the joint surface repair at 4 weeks. The defect having 2.0-mm depth in G-I, II, and III was completely filled with a white opaque tissue. The defect having 3.0-mm depth in G- II and III was completely filled with a white opaque tissue, while the defect in G-I was filled with inhomogenous white and reddish tissue. The defect in G-IV showed reddish opaque, patchy tissues, independent of the depth. G-I; a 0.5-mm gel sheet was implanted at the bottom of the defect. G-II; a 1.0-mm gel sheet was implanted at the bottom of the defect. G-III; a 5.0-mm gel plug was implanted at the bottom of the defect. G-IV; the control group has a defect left untreated.