Effects of combined hydroxyapatite and human platelet rich plasma on bone healing in rabbit model: radiological, macroscopical, hidtopathological and biomechanical evaluation

Abstract

Hydroxyapatite is an osteoconductive material used as a bone graft extender and exhibits excellent biocompatibility with soft tissues such as skin, muscle and gums, making it an ideal candidate for orthopedic and dental implants or components of implants. Synthetic hydroxyapatite has been widely used in repair of hard tissues, and common uses include bone repair, bone augmentation, as well as coating of implants or acting as fillers in bone or teeth. On the other hand, human platelet rich plasma (hPRP) has been used as a source of osteoinductive factor. A combination of hPRP and hydroxyapatite is expected to create a composite with both osteoconductive and osteoinductive properties. This study examined the effect of a combination of hydroxyapatite and hPRP on osteogenesis in vivo, using rabbit model bone healing. A critical size defect of 10 mm long was created in the radial diaphysis of 36 rabbit and either supplied with hydroxyapatite-human PRP or hydroxyapatite or was left empty (control group). Radiographs of each forelimb were taken postoperatively on 1st day and then at the 2nd, 4th, 6th and 8th weeks post injury to evaluate bone formation, union and remodeling of the defect. The operated radiuses of half of the animals in each group were removed on 56th postoperative day and were grossly and histopathologically evaluated. In addition, biomechanical test was conducted on the operated and normal forearms of the other half of the animals of each group. This study demonstrated that hydroxyapatite-humanPRP, could promote bone regeneration in critical size defects with a high regenerative capacity. The results of the present study demonstrated that hydroxyapatite-hPRP could be an attractive alternative for reconstruction of the major diaphyseal defects of the long bones in animal models.

Three-Dimensional Porous Gelapin–Simvastatin Scaffolds Promoted Bone Defect Healing in Rabbits

“…1 mg/kg Xylazine HCl (Alfasan Co., Woerden, Netherlands), respectively [19][20][21]. Under aseptic condition, a dorsomedial skin incision was made over the forearm, the extensor muscles and tendons were retracted, and the radial bone was exposed.…”

Role of tissue engineering in tendon reconstructive surgery and regenerative medicine: Current concepts, approaches and concerns

“…Platelet-rich plasma is another healing promotive agent that initiates cell proliferation and tissue maturation 20,23,32 . These beneficial effects have been suggested to be due to the growth factors that are delivered from the platelets 62,64 . It seems that by equipping the tissueengineered scaffolds with cells and healing promotive agents, the tissueengineered graft could be optimized to open new insights in the field of tendon reconstructive surgery and regenerative medicine 12 .…”

Tendon and Ligament Tissue Engineering, Healing and Regenerative Medicine

“…Perhaps, preparation method of PRP, its concentration, source (e.g. auto-alloand xenogenic base) and its constitutions (platelet or platelet with buffy coat) are suggested to be different between several studies [30,[101][102][103]. As a general rule, effective PRP is prepared via two steps centrifugation with the combination of platelets and buffy coats (inflammatory cells) and has a 6 to 7 times more platelets than the circulating blood [30].…”

“…In vivo animal based investigations have showed beneficial effects of PRP in tendon and ligament healing while its value in clinical trial studies is questionable [103][104][105][106]. This substantial differences has been suggested to be related to the source of PRP [30].…”