Effect of daCO-DM modified 3D-printed module on bone regeneration. (a) Circle implanted module (Φ = 4.5 mm) before implantation. (b) Critical-sized parietal bone defect model. (c) Modules were implanted in vivo for 4weeks and 8 weeks (before harvest). (d) PET-CT images of mouse critical parietal bone defect implanted with four group modules of none-DM, BMSC-DM, WTO-DM, and daCO-DMat 4 and 8 weeks, n=5. (e) H.E. staining of the cross-sections to show the histological morphology of the regenerative repair at 8 weeks. red arrow, osteoblast; black arrow, new bone. Scale bars 500 μm and 20 μm.(f) The relative new bone formation was calculated by normalization to new bone formation area in the defects, which was measured by ImageJ software. Bone area per tissue area (B.Ar/T.Ar). (g) Bone formation ratio was measured by ImageJ software based on H.E. stained cross-sections at 8 weeks BV/TV, bone volume per tissue volume, N.Ob/T.Ar, number of osteoblasts per tissue area , n = 5. DM, decellularized matrix; none-DM, PCL scaffold; BMSC, bone marrow stromal cell; WTO, wild-type osteocytes; daCO, osteocyte with dominant active β-catenin. Sections with newly formed bone were measured for each mouse. Data were expressed as mean ± SD. *p < 0.05 v.s. none-DM #p < 0.05 v.s. BMSC-DM, $p < 0.05 v.s. WTO-DM by one way ANOVA.