Bone Growth Capacity of Human Umbilical Cord Mesenchymal Stem Cells and BMP-2 Seeded Into Hydroxyapatite/Chitosan/Gelatin Scaffold in Alveolar Cleft Defects: An Experimental Study in Goat

Objective: To evaluate bone regeneration in alveolar defects treated with human umbilical cord-derived mesenchymal stem cells (hUCMSCs), hydroxyapatite/chitosan/gelatin (HA/CS/Gel) scaffold, and bone morphogenic protein-2 (BMP-2) in Capra hircus models. Design: Randomized posttest-only control group design. Setting: Animal Hospital at Bogor Agricultural Institute. Participants: Healthy and equally treated 24 female Capra hircus/goats. Intervention: Animals were randomly assigned to 3 experimental group design (iliac crest alveolar bone graft/ICABG [control], HA/Cs/Gel+BMP-2 [Novosys], and HA/Cs/Gel+BMP-2+UCMSCs). Graft materials were implanted in surgically made alveolar defects. Main Outcome Measures: Postoperative functional score and operating time were assessed. New bone growth, bone density, inflammatory cells recruitment, and neoangiogenesis were evaluated based on radiological and histological approach at 2 time points, week 4 and 12. Statistical analysis was done between treatment groups. Results: Operating time was 34% faster and functional score 94.5% more superior in HA/Cs/Gel+BMP-2+hUCMSC group. Bone growth capacity in HA/Cs/Gel+BMP-2+UCMSCs mimicked ICABG, but ICABG showed possibility of bone loss between week 4 and 12. The HA/Cs/Gel+BMP-2+UCMSCs showed early bone repopulation and unseen inflammatory cells and angiogenesis on week 12. Discussion and Conclusion: The HA/Cs/Gel+BMP-2+hUCMSCs were superior in enhancing new bone growth without donor site morbidity compared to ICABG. The presence of hUCMSCs in tissue-engineered alveolar bone graft (ABG), supported with paracrine activity of the resident stem cells, initiated earlier new bone repopulation, and completed faster bone regeneration. The HA/Cs/Gel scaffold seeded with UCMSCs+BMP-2 is a safe substitute of ICABG to close alveolar bone defects suitable for patients with cleft lip, alveolus, and palate.