Bone Healing in a Rabbit Mandibular Defect Using Platelet-Rich Plasma

Purpose: To evaluate the effect of platelet-rich plasma (PRP) on bone healing in an osteotomized defect of the rabbit mandible. Materials and Methods: Twelve adult female New Zealand White rabbits were randomized to 1 of 2 treatment groups: group A had an osteotomy with the addition of a bone graft, and group B had an osteotomy without a bone graft. Regardless of treatment group, 1 side in each rabbit was randomly selected to receive PRP as an internal control. Bilateral 1.0- × 0.5-cm mandibular inferior border osteotomies were performed in each animal, 0.5 cm anterior to the antegonial notch to create mandibular defects. The osteotomy sites were evaluated by histologic and radiographic analyses for bone healing at 1, 2, and 3 months after surgery. Results: A 4-point ordinal scale was used to compare healing, based on radiographic density, radiographic height, and histologic height of new bone formation. Group A rabbits showed significantly shorter healing times compared with group B rabbits. A pairwise analysis indicated that the addition of PRP did not increase the overall score of any measured parameter, at any interval (P > .9). Conclusions: In the rabbit osteotomy model, bone grafting (group A) significantly improved healing in comparison with no bone grafting (group B). In defects of the mandible, an increased radiographic and histologic bone density and height were seen at 1-, 2-, and 3-month intervals in the bone graft group; however, the addition of PRP did not appear to provide any statistically significant benefit to healing in either group.