(a) Histological findings of Toluidine blue staining (TB) and Hematoxylin and eosin (H–E) staining (HE) in each group with PLLA scaffolds at 1, 3 and 6 months after the transplantation. HE stain showed that there is no osseous structures formation in each group. Proteoglycan was observed as metachromasia in the constructs with PLLA/cells/iliac and constructs with PLLA/cells in TB stain. (b) The observation revealed that the areas of metachromasia increase with time.