Objective: To evaluate the potential of bioresorbable collagen membrane in a combination with bone marrow stromal cells (BMSCs) or platelet rich plasma (PRP) in repairing alveolar bone defects.
Methods: The first and second premolars were extracted from the bilateral maxillary and mandibular bone and four alveolar intrabone defects (8 mm in height, 5 mm in width, 15 mm in length) were created in 3 male mongrel dogs. The experiment included 4 groups: group A (nothing was used as control group), group B (only Bio-Gide), group C (Bio-Gide/ BMSCs) and group D (Bio-Gide/PRP). The macroscopic, radiographic and histological observations were performed at 4, 8 and 12 weeks after surgery.
Results: The cells were circle or short spindle-shape after 1 day of co-culture; and the cells were polygon and long spindle-shape with process after 3 days. The macroscopic observation: after 4 weeks in the defect region, obvious excavation and organization of hematoma were seen in group A; and new bone formation and little organization of hematoma were seen in groups B, C, D. After 8 weeks, excavation was not obvious, fibrous tissue was seen at the top of defect, organized hematoma was gradually replace by new bone in group A; the edge of membrane broke and adhered to deep tissue and needle could pierce the surface of defect in groups B, C, D. After 12 weeks, excavation disappeared in 4 groups and fibrous tissue at top of alveolar ridge in group A was thicker than that in groups B, C, D. The radiographic observation: defect was full of new bone. In groups A, B, C and D, the grey values were 68, 50, 56 and 49 after 4 weeks; 46, 30, 24 and 30 after 8 weeks; and 24, 17, 15 and 20 after 12 weeks respectively. The histological observation:after 4 weeks, a lot of fibrous connective tissues granulation tissues were seen no obvious new bone formed in group A; and the collagen structure of membrane remained and new bone formed in medial surface in groups B, C, D. After 8 weeks, new bone trabecula displayed clump and web in group A; the collagen structure of membrane were not of integrity, and many bone islands and few fibrous connective tissue formed in groups B, C, D. After 12 weeks, defect was filled with new bone in 4 groups.
Conclusion: Guided bone regeneration (GBR) treatment with collagen membranes may significantly enhance bone regeneration within 8 weeks. The influence of GBR in combination with BMSCs or PRP in accelerating the repair of alveolar bone defects shoud be further investigated.