Aim: The aim of this work was to evaluate bone regeneration capacity of 
Xenogeneic bone graft and Bone marrow mesenchymal stem cells (BMSCs) mixture 
in Osseous Jaw defects. Subjects and Methods: This study was carried out on 10 
patients, aging from 15 to 50 years old, who had osseous defects due to benign tumor 
or large cyst ≥3cm3
 by clinical and radiographic examination. All Defects were 
grafted with a mixture of BMSCs seeded into collagen sponge and xenogeneic bone 
graft. All patients were subjected to a panoramic radiograph, cone-beam computed 
tomography (CBCT) to assess jaw bony defect size, bone volume, and bone density. 
Results: The significance evaluation for volumetric changes for each time interval 
revealed significant difference (P < 0.05) except for immediate postoperative which 
were insignificant different. The significance evaluation for bone density each time 
interval revealed insignificant difference except for bone density change percentage 
which revealed significant difference (P<0.05). Conclusion: The use of autologous 
BMSCs seeded on gelatin scaffold combined with xenogeneic bone graft was promising 
for regenerating bone at odontogenic large defects ≥ 3 cm3
.