الفهرس | Only 14 pages are availabe for public view |
Abstract The reconstruction of critical size bony defects is a major challenge that face many craniomaxillofacial and reconstructive surgeons. Theses defects could be encountered because of congenital or acquired etiologies as infection, trauma, post cancer ablative surgery or deforming skeletal diseases. Moreover, various approaches are available for repair by bone grafts, bone substitutes, bone transport methods or bone tissue engineering. The autografts are still the golden standard for reconstruction of critical size defects without any doubt. But on the other hand, its use is limited by graft availability, bone resorption donor site morbidity and the need of extra surgery for harvest. So, recent researches are directed towards building an already made bone tissue regenerate that mimic the natural bone in osteoconductivity, osteoinductivity, osteogenesis, biocompatibility and non-immunogenicity and at the same time, to be available, easily prepared, applied and stored. The enormous advances in the cell mediated bone tissue engineering conducted the stem cells as a rich, safe and a non-immunogenic source for multipotent cells with diverse plasticity that can be directed towards osteogenesis either in vivo or in vitro. The adipose tissue is abundant source for ADSCs, which is proved to have a powerful osteogenic differentiation with greater long-term survival abilities in adverse environments such as traumatic, hypoxic, and nutrient starved conditions. It can be harvested easily even from lipoaspirate which was thought to be a waste despite its richness for ADSCs that can be isolated and preserved even for 6 months at low temperatures without losing their abilities to differentiate and proliferate Despite the osteogenicity of ADSCs, it needs to be seeded over an ideal scaffold and to be induced by growth factors to complete the triad of bone tissue engineering. The DBM is considered an ideal scaffold as it has good biocompatibility with a controllable degradation rate. It also has a suitable surface chemistry for cell attachment, proliferation and differentiation. It is a non-immunogenic scaffold that can be harvested from allogenic donors and implanted safely in the host. Moreover, it is osteoconductive with a slight osteoinductive ability. The results obtained in this study revealed a statistically significant bone healing after reconstruction of critical size calvarial bone defects by ADSCs seeded on allogenic DBM. In conclusion, this study presents a beneficial method for reconstruction of critical size calvarial bone defects by an already made non-immunogenic new tissue regenerate. |