Effects Of Platelet-rich Plasma And Seeding Periodontal Ligament Cells On The Healing Of Periodontal Furcation Defects

Objective The first aim of this study was to evaluate the influence of platelet-rich plasma (PRP) on the attachment and proliferation of periodontal ligament cells (PDLCs) on cementum slices of health teeth and periodontitis affected teeth. The second aim was to compare the regeneration effect of seeding different amount of autologous periodontal ligament cells into canine artificial furcation defects.Methods 1. Platelet-rich plasma (PRP) was isolated by two-step centrifugation. The 4th passage of human PDLCs were used in this experiment. The cementum slices of health teeth and periodontitis affected teeth were prepared and were put on the 96-well tissue culture plates, and PDLCs were seeded on the cementum slices. Attachment and proliferation of cells were studied by MTT assay. And the status of cells on the cementum slices were observed by electro microscope. 2. Twenty-four experimental class II furcation defects in four Beagle dogs were created surgically, GTR combination with the expanded PDLCs which were seeded in collagen membrane at initial concentration of 5×105 cells/ml, 5×106 cells/ml, or 5×107 cells/ml, and auto-transplanted 1×104, 1×105, 1×106PDLCs into experimental classⅡfurcation defects, underneath a Bio-Gide membrane alone was implanted into the defects as control. The animals were sacrificed at 12 weeks postsurgery and periodontal regeneration was evaluated by histological and morphometric analysis.Results 1. In the attachment experiment, the PDLCs on cementum slices were significantly increased by addition of 10%PRP, but in the proliferation experiment, there were no significant difference between the experiment group and the control group. 2. In both the experimental groups and the control group, there were different extent of regeneration. Histometric analysis showed that the percentage of new bone area in the 1×106PDLCs group were significantly higher than in the control group.Conclusion 1. The attachment of PDLCs on cementum slices was improved by addition of 10%PRP, but 10%PRP had no effect on the proliferation of PDLCs on cementum slices. 2. Auto-transplantation of periodontal ligament cells is a novel option for periodontal tissue regeneration, and the effective concentration is 5×107/ml , the effective amount is 1×106.