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Table 1: Modified Lane and Sandhu radiological scores, mean new bone formation in Histology (%), and mean
compressive strength (MPa) of the rabbit’s radius in each group at 3 months after surgery
Group Scaffold implantation Mean radiological Mean compressive Mean new bone
scores strength (MPa) in Histology (%)
1 HDCB only 2.95 ± 0.58 31.14 ± 6.72 29.60 ± 8.33
2 Periosteum-wrapped HDCB 5.57 ± 0.51 73.00 ± 7.20 49.79 ± 11.69
3 HDCB/BM-MSCs 6.41 ± 1.03 80.57 ± 8.50 64.12 ± 11.31
4 Periosteum-wrapped HDCB/ 8.58 ± 0.64 129.31 ± 5.99 80.50 ± 4.96
BM-MSCs
HDCB: Human demineralized cancellous bone, BM‑MSCs: Bone marrow mesenchymal stem cells
source, which is more convenient for isolation and
expansion when compared with periosteum‑derived cells.
To further enhance the current bone tissue engineering
strategies, a successful cellular replacement for periosteum
or tissue‑engineered periosteum should be investigated.
Zhang et al. previously reported successful regeneration
[11]
of segmental bone defects in rabbit ulnas using
periosteum encapsulated scaffolds seeded with MSCs,
with an increase in the newly formed bone area to
80.1% ± 9.6%. This result is compatible with the results of
the current study at 80.5% ± 4.96%.

Xenogeneic demineralized cancellous bone grafts, which
have the advantages of favorable cellular compatibility
and histocompatibility as a scaffold, have widely been
used for the repair of short bony defects showing the
Figure 4: HE stained histological sections from the grafted bone of four induction of NB formation and good mechanical properties.
groups at 3 months after implantation (original magnification, ×40). Osteoinductive structures in demineralized bone graft
NB: New bone, VC: Vascular cavity, BM: Bone marrow, P: Periosteal membrane
include a series of low‑molecular‑weight glycoproteins with
bone morphogenetic proteins. These proteins promote
inner cambium layer is highly cellular and populated with chondroblastic differentiation of mesenchymal cells and
cells, which influence bone formation and bone repair, create NB formation via endochondral osteogenesis. [1,31,35]
including adult mesenchymal skeletal progenitor cells. [29,31] The bone formation process increases when decalcification
These progenitor cells proliferate and differentiate into of cortical bone exposes osteoinductive growth factors
osteoblastic and chondroblastic cells, driving the process buried within the mineralized matrix. However, bone
of bone repair via either direct intramembranous grafting has not been successful in the repair of large
bone formation or indirect endochondral mechanisms, bone defects. BM‑MSCs, which can be seeded to the
[13]
[32]
respectively. On the contrary, the absence of periosteum HDCB graft for construction of the tissue engineered bone
reduced by 75%, the number of osteoblasts on devitalized graft, has been suggested as an effective option for the
bone graft, which correlated with the poor remodeling reconstruction of large bone defects.
activity of the bone graft. These features indicate that
[33]
periosteum should be considered to be a structure with In the group repaired by periosteum‑wrapped HDCB
regenerative capacity. This suggests the need to restore the graft seeded with BM‑MSCs, bone healing and union
essential osteogenic activity of periosteum on bone graft were significantly accelerated as compared to the other
in combination with grafting of MB‑MSCs. This approach three groups. Increased density at the graft site and early
assists in the early induction of a reparative response by fusion of cortical bone were observed. In addition to
an increase in the formation of a cortical shell around NB formation demonstrated histologically, a significant
the grafted bone. [34,35] Agata et al. have also shown that amount of regenerated capillary vasculature between
[34]
periosteal cells act as progenitor cells with the ability to the NBs was also being observed in a high proportion of
[11]
proliferate and expand. Thus, periosteum‑derived cells are grafted bone pores. Zhang et al. reported similar results
another suitable source for bone tissue engineering. when incorporating MSCs and periosteum‑loaded poly
scaffolds. However, our findings have notable differences
Based on clinical observation, radiologic examination, from the results of Zhang et al., as HDCB/BM‑MSCs
[11]
histological analyses and biomechanical measurements, grafts were significantly superior to periosteum‑wrapped
the current study supports the essential role of periosteum HDCB grafts in terms of union rates and capillary density.
in the process of bone repair. In addition, the regenerative
effect of combining BM‑MSCs with periosteum showed For improved biochemical analysis for bone regeneration,
better outcomes in both the quantity and quality as a three‑point bending test should be performed to
compared to BM‑MSCs alone. Furthermore, the MB‑MSCs evaluate the degree of scaffold integration with the host
used in the current study are derived from an allogenic bone.

344 Plast Aesthet Res || Vol 2 || Issue 6 || Nov 12, 2015