Figure 4
From: Osteoinductive 3D printed scaffold healed 5 cm segmental bone defects in the ovine metatarsus
Representative photomicrographs of ISO-10993-6 Histological Scoring Parameters. (A,B) Overall osteogenic response (total new bone production) scores of 4 in both a control (SM04) and scaffold-treated animal (SM02). Tissue sections are predominated by anastomosing trabeculae of new bone (white asterisk). Intertrabecular spaces are composed of either fibrosis (arrowhead, A) or void space left from the implant (B). ×4 magnification. (C,D) Images demonstrating fibrosis scores of 1 in both a control (SM01) and scaffold-treated animal (SM02). Thin bands of dense fibrous connective tissue (arrow in C, arrowhead in D) are juxtaposed between new bone and defect or implant void spaces. ×10 magnification. (E,F) Image demonstrating cumulative inflammation scores of 2 in a control animal (SM01) and 5 in a scaffold-treated animal (SM02). Inflammation in control animals (E) was characterized by few scattered lymphocytes and plasma cells (arrows) within the fibrous tissue, while scaffold-treated animals (F) were characterized by infiltrates of macrophages and multi-nucleate giant cells (arrows) present in the fibrous tissue between new bone (white asterisk) and the implant void space (black asterisk). ×20 magnification. (G,H) Osteoblast activity scores of 2 in a control animal (SM04) and 1 in a scaffold-treated animal (SM03). Few clusters of plump osteoblasts (arrows) segmentally line endosteal surfaces of new bone. ×20 magnification. (I,J) Osteoclast activity scores of 1 in both a control (SM04) and scaffold-treated animal (SM03). Rare osteoclasts (arrows) were observed along endosteal surfaces of new bone. ×20 magnification. All scale bars indicate 200 μm. Images were captured with an Olympus BX51 microscope and Olympus DP73 camera using Olympus cellSens Entry software (version 2.3, https://www.olympus-lifescience.com/en/software/cellsens/).
