Fig. 2From: The impact of collagen membranes on 3D gingival fibroblast toroidsAttachment and metabolic activity of gingival fibroblast toroids on plastic or collagen membranes. Gingival fibroblast toroids on plastic (N = 5) (a) did not show any changes in shape over 72 h, but were metabolically active as shown in relative fluorescence units (N = 3) (b). Gingival fibroblast toroids on collagen membranes showed dilatation after 48 h and 72 h (N = 5) (c) and were metabolically active over the whole observation period (N = 3) (d). Error bars represent standard deviationBack to article page