Osteogenic Potential of Zirconium Enriched Bioglass on Differentiated Amniotic Fluid Derived Stem Cells and Healing of Tibia Rabbit Defect

Aims: The regeneration prospects of human bone seem to be confined due to different systemic and environmental conditions that may affect many patients. This work aimed to evaluate the biocompatibility and osteogenic potential of the prepared novel nano-bioactive glass including zirconium (NZBG) in-vitro and in-vivo studies.

Study Design: The novel nano-bioactive glass (NZBG) was fabricated by sol- gel rout for the development of bone tissue replacement.

Place and Duration of Study: NZBG: Faculty of Oral and Dental Medicine Dept. (Cairo University), Medical molecular genetics Dept. (National Research Centre (NRC), Prenatal diagnosis and fetal medicine Dept. (National Research Center) and Ceramics Dept., Biomaterials group (National Research Center) between June 2015 and July 2017.

Methodology: The novel nano-bioactive glass (NZBG) was fabricated by sol- gel rout for the development of bone tissue replacement. The prepared nano-bioactive glass (NZBG) was characterized by Photo correlation spectroscopy (PCS), transmission electron microscope (TEM), X-ray powder diffraction (XRD) and Fourier Transform infrared spectroscopy (FTIR) before the in-vitro and in-vivo studies. The in-vitro evaluation of nano-bioactive glass NZBG was obtained through seeding human osteogenic cells from amniotic fluid derived stem cells on NZBG disks in culture for different time periods, 7 and 21days. The cultures were examined for mineralization by Alizarin Red Staining. The in-vitro mineralization was evaluated by scanning electron microscopy- X-ray microanalysis (SEM- EDAX) test.

The in-vivo evaluation was done on thirty adult rabbits weighing between 2 kg and 2.5 kg. Two holes in each tibia, with a diameter of 2 mm were prepared. One of them was left without treatment as control group and the other was filled with NZBG bioactive glass. The animals were euthanized after 1, 2 and 3 weeks. The defects were examined histologically by H&E, histochemically by Masson's trichrome stain and histomorphometrically.

Results: The in-vitro examination showed the enhanced osteoblastic proliferation over the NZBG

bioactive glass disks and clusters of bone like apatite mineralization in multilayer arrangements that increased by time. While the in-vivo study demonstrated well and proper healing of the defect filled with NZBG bioactive glass regarding the bone quality and quantity in comparison to the control group.

Conclusion: An enhanced biocompatibility and faster osteogenesis with the prepared NZBG bioactive glass. This is meaning the prediction good potential applications to bone regeneration medicine.