Platelet concentration and its effect on bone formation in calvarial defects: an experimental study in rabbits.

STATEMENT OF PROBLEM The use of the platelet concentration technique is widespread in dental implant surgery. However, its effect or mechanism is not clearly understood. PURPOSE This study introduced an animal model for the platelet concentration technique and evaluated its effect on bone formation with natural cancellous bovine bone mineral. MATERIAL AND METHODS Adult New Zealand white rabbits were used as the animal model. A density gradient medium was used to obtain a constant platelet count for the preparation of platelet concentrates. In the experimental group, natural cancellous bovine bone mineral with added platelet concentrates was grafted onto critically sized bony defects of the rabbit calvarium. Bone formation in the tissue sections was evaluated with soft x-ray imaging and computer tomography. RESULTS The average platelet count of the rabbit platelet concentrates was 1487 x 10(3)/microL (287% concentrated). In all the tested parameters, greater bone densities were obtained in grafts that were combined with platelet concentrates. CONCLUSION This study showed that the rabbit is a useful animal model for studying the platelet concentration technique. When combined with grafts of natural cancellous bovine bone mineral, the technique increased bone formation.