Comparative Evaluation of Platelet-rich Plasma and Guided Tissue Regeneration Membrane in the Healing of Apicomarginal Defects: A Clinical Study Bhawna Goyal, MDS,* Sanjay Tewari, MDS,* Jigyasa Duhan, MDS,* and P.K. Sehgal, MD † Abstract Introduction: The aim of the study was to compare the healing responses of platelet-rich plasma (PRP), PRP + a collagen sponge, and a collagen membrane used as guided tissue regeneration (GTR) materials for the treat- ment of apicomarginal defects. Methods: Thirty patients with suppurative chronic apical periodontitis and apico- marginal communication were selected and allocated randomly into three groups according to the barrier technique to be used during periradicular surgery: the collagen membrane group, the PRP group, and the PRP + collagen sponge group. Clinical and radiographic measurements were determined at baseline and every 3 months after surgery up to 1 year. Cases were defined as healed when no clinical signs or symptoms were present, and radiographs showed complete or incomplete (scar tissue) healing of previous radiolucencies. Results: The PRP and PRP + collagen sponge groups depicted 83.33% and 88.89% healing, respectively, in terms of combined clinical-radiographic healing as compared with 80% in the collagen membrane group. All the three treatments showed highly significant (P < .05) reductions in the periodontal pocket depth (PD), the clinical attach- ment level (CAL), the gingival margin position (GMP), the size of the periapical lesion, the percentage reduction of the periapical rarefactions, and periapical healing. No significant differences between the three groups were evident for these parameters (P > .05). Conclusions: GTR applied to apicomarginal defects using PRP or PRP + collagen sponge lead to similar enhancements of the clinical outcome of periradicular surgery in terms of periapical healing, gain of periodontal support, PD reduc- tion, and PRP may be an alternative treatment for GTR membrane in the treatment of apicomarginal defects. (J Endod 2011;37:773–780) Key Words Apicomarginal communication, clinical study, collagen sponge, guided tissue regener- ation, periapical surgery, platelet-rich plasma P eriradicular surgery is an established treatment option in endodontics for the management of periapical pathologies. The amount and location of bone adjacent to the root structures affect the prognosis of periradicular surgery. In general, the prog- nosis of periradicular surgery varies between 25% and 90% (1). However, when bony destruction of the pathological process includes a localized loss of marginal bone, the prognosis for success is reported to be 27% and 37% (2, 3). The reason for the limited success has been identified as the formation of long junctional epithelium over the dehisced root surface (4). Although apicomarginal defects are infrequent, they represent a significant challenge to healing. Guided tissue regeneration therapy introduced in 1980s has been widely used to regenerate lost periodontium from periodontal disease. Guided tissue regeneration (GTR) therapy has also been implemented in the endodontic surgeries as a concomitant treatment during the management of endodontic-periodontal lesions (5–8). These studies have shown significantly higher success with the use of GTR membrane in apicomarginal defects. The placement of a physical barrier over an osseous defect can prevent the faster proliferating oral epithelium and gingival connective tissue from growing into the bone defect, allowing the cells of the periodontal ligament and endosteum to colonize the blood clot and regenerate the lost tissue (9). However, GTR membranes are also associated with certain disadvantages like its high cost, the possibility of contamination, a difficulty in proper flap approximation, and also a greater risk for mechanical trauma resulting in micro endo-perio communica- tions (possibility of infection) (10). Some studies have also reported the risk of root resorption and ankylosis with the use of GTR membrane (11, 12). A membrane barrier might actually prevent osteoprogenitor cells in the periosteum from proliferating into the bone defect to help new bone formation (13). In recent years, platelet-rich plasma (PRP) combined with graft materials has been used for the purpose of periodontal regeneration (14, 15). PRP is a volume of autologous plasma that has a higher platelet concentration than baseline. Concentration of platelets increases by up to 338% because of the application of PRP in surgical sites (16). It is known that an increased number of platelets deliver an increased number of polypeptide growth factors that regulate cell proliferation, chemotaxis, and differentiation to the surgical area with PRP. The aggregation of platelets releases chemotactic factors for leukocytes along with growth factors such as platelet-derived growth factor (PDGF) and transforming growth factor (TGF)– a and –b, which promote tissue regeneration (16). One case series (17) and one histologic study (18) comparing autologous platelet concentrate with a bioab- sorbable membrane in periodontal defects found similar results between the two groups, suggesting that autologous platelet concentrate could be used in lieu of a membrane for periodontal GTR applications (17, 18). However, in endodontics, no reports have been found comparing the efficacy and equivalence of PRP with GTR membrane during the treatment of apicomarginal defects. Therefore, the purpose of this clinical study was to compare the healing response of PRP and From the *Department of Conservative Dentistry and Endodontics, Government Dental College; and † Department of Blood Transfusion, PGIMS, Rohtak, Haryana, India. Address requests for reprints to Dr Sanjay Tewari, Senior Professor and Head, Department of Conservative Dentistry and Endodontics, Government Dental College, Rohtak, Har- yana, India. E-mail address: tewarisanjayrohtak@yahoo.co.in 0099-2399/$ - see front matter Copyright ª 2011 American Association of Endodontists. doi:10.1016/j.joen.2011.03.003 Clinical Research JOE — Volume 37, Number 6, June 2011 Role of PRP in the Healing of Apicomarginal Defects 773