The Clinical Application Of Three-Dimensional Printing Alveolar Bone Defect Model Guided Advance/Injective Platelet Rich Fibrin Technology In Regenerative Periodontal Surgery

Background:Periodontitis is the main cause of tooth loss in adults,and the most difficult area in the treatments of which is to reconstitution and regeneration of periodontal attachment apparatus.So far,the guided tissue regeneration(GTR)and bone replacement graft are the most commom therapeutic approaches for periodontal tissue regeneration.However,with the shortage of limited indications,insufficient outcomes and lack of regeneration activity,these procedures has not meet the desired clinical goals for restoreing the structure and function of distructive tissue.In recent years,autologous blood-derived platelet rich fibrin(PRF)has attracted much attention due to its safety,immunogenicity and high regenerative activity with enrichment of growth factors.Currently,with the popular of cone beam computed tomography(CBCT)and three dimensional printing(3D printing)in medical application,3D reconstruction and 3D printing of surgical model make it possible to achieve the accurate treatment design,defect repair and surgery efficacy evaluation.Objective:This study is to apply the 3D printed technology into clinical periodontal surgery and add the advanced platelet rich fibrin(APRF)and injective platelet rich fibrin(IPRF)into normal GTR procedure.Besides,CBCT is used to explore the application value of this novel procedure in promotion of periodontal defects repair.And the study might offer new idea for clinical periodontal regenerative therapyMethod:Total of 5 patients diagnosed as chronic periodontitis from July,2015 to March,2017 were enrolled at the outpatient of department of Periodontology,second affilicated hospital of Zhejiang university school of medicine.They were all received initive therapy,and showed inrabony defect which need regenerative surgery after the re-evaluation.The periodontal examination and CBCT were performed 6 months before and after the operation.A 3D printed bone defect model of treated site was made based on the CBCT data and used during the surgery.Changes of clinical indexes and radiological values of the periodontal depth(PD),clinical attachment level(CAL),radiological bone level(RBL)and intrabony component(IC)depth were measured and analyzed.The filling rate of defect(DF,DR)was calculated to evaluate the therapeutic effect.Result:All surgical wound were healing well.The clinical parameters were signilicantly improved.It was observed from CBCT that the bone replacement graft keeping stable in the alveolar bone defect and the defect bottom rose higher 6 months after treatments.Conclusion:The 3D printing model guided APRF/IPRF combined with GTR procedure was able to achieve good clinical results to repair periodontal bone defects and improve the effects of concentional regenerative surgeries.And CBCT could be used to quantitatively evaluate the effectiveness of regenerative surgery.However,larger samples with long term randomized controlled trials is needed to prove the results and further study.