|Year : 2018 | Volume
| Issue : 2 | Page : 72-77
A comparative evaluation of porous hydroxyapatite bone graft with and without platelet-rich plasma in the treatment of periodontal intrabony osseous defects: A clinico-Radiographic study
Gouri Bhatia1, Manish Khatri2, Mansi Bansal2, Sameer Saxena1, Vipin Agarwal3, Ashish Kumar2
1 Department of Periodontology, Teerthanker Mahaveer Dental College and Research Centre, Moradabad, Uttar Pradesh, India
2 Department of Periodontology, Institute of Dental Studies and Technologies, Modinagar, Uttar Pradesh, India
3 Department of Periodontology, Seema Dental College and Hospital, Rishikesh, Uttarakhand, India
|Date of Web Publication||8-Jun-2018|
Department of Periodontology, Teerthanker Mahaveer Dental College and Research Centre, N.H. 24, Delhi Road, Moradabad - 244 001, Uttar Pradesh
Source of Support: None, Conflict of Interest: None
Background: Today, regenerative attempts for treatment of periodontal disease focus on the introduction of a filler material into the defect in hope of inducing bone regeneration. The purpose of this study was to clinically and radiographically evaluate the use of porous hydroxyapatite bone graft with and without platelet-rich plasma (PRP) in the treatment of intrabony defects. Materials and Methods: The study was carried out in ten patients between 18 and 60 years. Patients with pocket depth ≥5 mm and radiographic evidence of vertical bone loss in the affected site were randomly assigned to treatment with a combination of PRP + Hydroxyapatite (HA) (test sites) or HA alone (control sites). The parameters were compared at baseline and 6 months postoperatively. Results: There was a statistically significant reduction in probing depth and gain in clinical attachment in both the groups individually (more in experimental group); however, on comparing the two groups, the net reduction was not significant. Radiographic assessment showed a decrease in the defect size in both the groups. Conclusion: PRP in addition to a bone graft in the treatment of intrabony defects is safe and shows improved defect fill as compared to the use of bone graft alone.
Keywords: Bone graft, periodontal tissue regeneration, platelet-rich plasma
|How to cite this article:|
Bhatia G, Khatri M, Bansal M, Saxena S, Agarwal V, Kumar A. A comparative evaluation of porous hydroxyapatite bone graft with and without platelet-rich plasma in the treatment of periodontal intrabony osseous defects: A clinico-Radiographic study. Indian J Dent Sci 2018;10:72-7
|How to cite this URL:|
Bhatia G, Khatri M, Bansal M, Saxena S, Agarwal V, Kumar A. A comparative evaluation of porous hydroxyapatite bone graft with and without platelet-rich plasma in the treatment of periodontal intrabony osseous defects: A clinico-Radiographic study. Indian J Dent Sci [serial online] 2018 [cited 2018 Oct 17];10:72-7. Available from: http://www.ijds.in/text.asp?2018/10/2/72/233980
| IntroductIon|| |
Periodontal therapy has always strived to control or eliminate periodontal disease in an attempt to restore the structures, integrity, and the function of tissues that have been lost as a result of inflammatory periodontal disease. A well-coordinated sequence of a number of biologic events including cell migration, adherence, multiplication, and differentiation has increased the predictability of periodontal regeneration. Treatment of intrabony defects has often focused on the bony defect and this has led to the use of a number of grafting materials to stimulate bone repair. Bone grafting materials when retained in the defect site provide a structural framework for clot development, maturation, and remodeling that supports bone formation in osseous defects. A wide array of bone graft substitutes is available today and has shown to produce greater clinical bone defect fill than flap debridement alone. Bioceramic alloplasts primarily composed of calcium phosphate are available as tricalcium phosphate and hydroxyapatite. Hydroxyapatite became the ceramic of choice, producing predictable short-term and long-term results. The graft material acts as a biocompatible material within the gingival tissue, and as it resorbs, it acts as a mineral reservoir and assists bone formation through osteoconductive mechanisms, resulting in clinically acceptable responses.,
A different approach used for periodontal regeneration in the present era is the use of growth factors that are a class of naturally occurring proteins which effectively stimulate the formation of mineralized as well as nonmineralized tissues. Platelet-rich plasma (PRP) as introduced by Marx is defined as an “autologous concentration of platelets in a small volume of plasma” and is considered to be a rich source of autologous growth factors. In the field of dentistry, PRP has been used in different clinical procedures (i.e., sinus floor elevation, alveolar ridge augmentation, mandibular reconstruction, maxillary cleft repair, treatment of periodontal defects, gingival recession, and treatment of extraction sockets), where it has been applied alone or in addition to bone grafts.,,,,, PRP once grafted into the defect site begins to release alpha granules within 10 min of clot development and secrete over 90% of their prepackaged growth factors within 1 h, thereby initiating a greater and faster initial cellular response than a normal blood clot. Platelet-rich-derived fibrin clot formation stimulates collagen synthesis in the periodontium and effectively promotes wound healing at sites of injury in periodontal tissue.,
Thus, the purpose of this study was to clinically and radiographically evaluate the use of porous hydroxyapatite bone graft with and without PRP in the treatment of periodontal intrabony osseous defects.
| Materials and Methods|| |
This randomized controlled study was carried out in the Department of Periodontology after approval by the Ethical Committee. The criteria for inclusion were systemically healthy individuals between age groups 18 and 60 years of either sex, no history of any medication affecting the periodontium in the past 6 months, and those who had not undergone any periodontal treatment in the past 6 months. Patients who had a clinical evidence of an intrabony defect with probing pocket depth (PD) ≥5 mm and radiographic evidence of angular bone loss in the affected site were included in the study. Patients excluded were individuals with systemic diseases (diabetes mellitus and platelet deficiencies), pregnant and lactating females, individuals with a present history of tobacco usage, and individuals on anticoagulant or immunosuppressive therapy.
The patients were subjected to oral prophylactic procedures, occlusal equilibration, if required, and routine laboratory investigations before surgery. Patients' oral hygiene status was evaluated by plaque Index (Silness and Loe) and gingival index (Loe and Silness). On reevaluation of Phase I therapy, only those patients who had attained a score of ≤1 were selected for the surgical phase.
To standardize the reproducibility of clinical measurements, occlusal acrylic stents for positioning the periodontal probe were fabricated on a cast obtained from an alginate impression. The following clinical parameters were recorded in a tabulated pro forma to the nearest millimeter with the help of a University of North Carolina-15 probe by a single investigator for each surgical site before surgery (baseline) and at 3 and 6 months after surgery. The pocket probing depth was calculated as the difference between the measurements from the fixed reference point (apical most end of the groove of the stent) to the base of the pocket and to the gingival margin. The clinical attachment level was recorded as the difference from the fixed reference point to the base of the pocket and fixed reference point to the cementoenamel junction (CEJ). Gingival recession was calculated as the difference between the measurements from the fixed reference point to the gingival margin and to CEJ.,
Preoperative radiographs were obtained at baseline and then at 3 and 6 months postsurgery. The size of the defect or defect fill was measured using depth of the infrabony component (INFRA I), INFRA II, and the bony defect width as described by Eickholz et al.
Before the commencement of the surgical procedure, the site to be treated was randomly allocated into experimental (PRP + Hydroxyapatite [HA]) or control (HA alone) study groups.
Platelet-rich plasma procurement
Just before the surgery, 10 ml of blood was withdrawn from the antecubital vein of the patients and collected in tubes containing sodium citrate anticoagulant. The test tube was placed into the automated centrifuge machine always ensuring that the tubes were counterbalanced, as per the centrifuge manual. The first cycle of 2400 rpm for 10 min separated the whole blood into a platelet-poor plasma layer at the top, a white buffy coat in the middle, and a layer of red blood corpuscles (RBC) at the bottom. The upper two layers and the top 1–2 mm of RBC layer were expressed into another tube (without anticoagulant) and centrifuged at 3600 rpm for 15 min that resulted in an upper portion of clear yellow supernatant with a very low concentration of platelets and a red-tinged bottom layer with highly concentrated platelets. At the time of application, PRP was combined with an equal volume of a sterile saline solution containing 10% calcium chloride (a citrate inhibitor) and human thrombin (an activator) which resulted in a sticky gel that was relatively easy to apply in surgical defects.,
A standardized conventional periodontal flap surgery was performed by a single operator. The site was anesthetized using adequate local anesthesia (2% lidocaine hydrochloride with adrenaline 1:80,000). Intracrevicular buccal and palatal incisions were given and full thickness mucoperiosteal flaps were elevated to expose the defect. A thorough debridement was carried out to ensure a clean site followed by thorough root planing. For the control site, adequate quantity of the graft (Biograft HA ®) was mixed with a few drops of saline to obtain a workable mass and the defect was filled [Figure 1]. At the experimental site, HA graft was mixed with PRP gel in a proportion of 1:1 and was inserted up to the vertical height of the corresponding adjacent bone level [Figure 2]. Flap was repositioned and sutured with 3-0 silk suture material (Ethicon) followed by a periodontal dressing. Postoperative instructions and medications were prescribed to the patients and were recalled after 10 days for suture removal. Postoperative care included reinforcement of oral hygiene and scaling when necessary. Patients were periodically monitored and the clinical and radiographic parameters were recorded at 3 and 6 months postsurgery.
|Figure 1: Control group (a) baseline probing pocket depth in 36, (b) baseline radiograph showing intrabony defect,(c) intrabony defect after debridement, (d) defect filled with hydroxyapatite bone graft, (e) 6-month postoperative probing depth, (f) 6-month postoperative radiograph showing bone fill|
Click here to view
|Figure 2: Experimental group (a) baseline probing pocket depth in 21, (b) baseline radiograph showing intrabony defect, (c) intrabony defect after debridement, (d) defect filled with platelet-rich plasma + hydroxyapatite bone graft(e), 6-month postoperative radiograph showing bone fill, (f) 6-month postoperative probing depth|
Click here to view
The collected data were assessed for both the control and the experimental groups individually as well as compared with each other using SPSS v19 (IBM, SPSS Statistics for Windows, IBM Corp, Armonk, New York, USA). Baseline, 3 months and 6 months postoperative data were tabulated and analyzed statistically.
| Results|| |
In the present study, twenty sites were selected from ten systemically healthy individuals (4 males 6 females; average 38.3 years) after fulfilling the inclusion criteria and were randomly allocated to control group or experimental group with the arch-wise distribution as shown in [Table 1].
|Table 1: Distribution of intrabony defect in relation to tooth type and treatment modality|
Click here to view
There was a reduction in mean plaque and gingival index scores from baseline to 6 months in both the groups with no statistical difference between the groups at all time periods [Table 2].
|Table 2: Comparison of mean values of oral hygiene status within and between control and experimental groups|
Click here to view
A statistically significant mean PD reduction was observed in the control group from baseline to 6 months (4.1 ± 1.66; P = 0.000) with a greater PD reduction in the experimental group (4.4 ± 1.35; P = 0.000). The difference between both the groups with respect to the mean PD reduction was statistically insignificant at different time intervals (P > 0.05) [Table 3].
|Table 3: Comparison of mean values of various parameters within and between control and experimental groups|
Click here to view
There was a greater CAL gain in the experimental group than in the control group at the end of 6 months (50% vs. 43.24%), although both of which were statistically significant (P = 0.00). On comparison between the groups, the change in the differences of their means from baseline to 3 and 6 months was not significant (P > 0.05) [Table 3].
No significant difference in the amount of gingival recession was seen in both groups at any point of time (P = 0.09 in control group and P = 0.46 in the test group from baseline to 6 months). The difference between the groups was also not statistically significant (P = 0.34) [Table 3].
In the control group, the amount of defect fill from baseline to 6 months posttreatment was 56.91% (P = 0.0007). For the experimental group, greater defect fill was observed from baseline to 6 months (57.16%; P = 0.00, respectively). When a comparison was made between the groups, statistically significant difference (P = 0.008) was seen in the differences of means between the groups from baseline to 3 months. However, from baseline to 6 months, the difference was not significant (P = 0.06) [Table 3].
| Discussion|| |
The management of periodontal osseous defects including the destruction of the periodontium has always been a challenge in clinical periodontics. A plethora of literature is available substantiating the use of bone graft materials along with growth factors with an aim to optimize the outcome of periodontal regeneration by assisting the proliferation, migration, and differentiation of periodontal ligament cells, cementoblasts, and osteoblasts. This study combined PRP with porous hydroxyapatite bone graft (Biograft HA ®) to enhance the regenerative potential of the graft used.
Various bone grafting materials have been used to fill periodontal intrabony defects with particle size between 300 and 500 μm in diameter, which has resulted in clinically acceptable responses., Hence, the particle size of porous hydroxyapatite bone graft (Biograft HA ®) used in this study was 350–500 μm. It has been seen that porous HA bone grafts have excellent bone conductive properties which permit outgrowth of osteogenic cells from existing bone surfaces into adjacent bone graft material. Since there are no organic components contained in HA, this bone graft material does not induce any allergic reaction; however, true periodontal regeneration is not achieved because the healing which occurs is a connective tissue encapsulation of the graft with a long junctional epithelium.,
Different techniques of PRP preparation have been known to yield substantially different amounts of cells, i.e., platelets and leukocytes as well as different levels of growth factors. As periodontal defects are small in size, only 8–10 ml of venous blood was withdrawn with a preparation time of about 30 min that is performed simultaneously during the surgery, thereby not increasing the chair-side time. The method of procurement of PRP used in this study was similar to that used in the study performed by Okuda et al. According to de Obarrio et al., PRP preparation assumes a sticky consistency, due to high fibrin content, making it a hemostatic and stabilizing agent that aid bone graft immobilization and has been suggested as an important event in wound healing. PRP is an autogenous preparation and is inherently safe and free from concerns over transmissible diseases. In the present study also, the lack of adverse reactions, abscesses, or rejection of implanted materials suggested that HA and PRP used were well tolerated and failed to show any foreign body reaction during the entire study period.
Improvement in plaque and gingival scores in the present study can be attributed to the fact that only those patients who showed maintenance of optimal oral hygiene were included in the study, and this level was maintained throughout the study period by reinforcement of plaque control measures and oral hygiene instructions at various recall periods. These results are in accordance with the results of Hanna et al. and Okuda et al. who reported that all patients enrolled for the study maintained very low mean plaque and gingival index scores at baseline and 6 months demonstrating high compliance with oral hygiene instructions. The change in probing depth and clinical attachment level could not be attributed to any significant difference in the levels of oral hygiene between both the groups.
Periodontal pocket is considered as a pathognomonic sign of periodontal disease and reduction in PD is one of the requisites for successful periodontal therapy. When both experimental and control groups were assessed individually, the mean reduction in the probing depth from baseline to 6 months showed statistically significant results. This reduction can be attributed to the decrease in inflammation, shrinkage of the pocket wall, change in the tissue tone and the placement of graft material into defect, that may modify the gingival tissue consistency thereby impeding the penetration of periodontal probe.,
Results of the present study are in conformity with the triple combination therapy including PRP, bovine porous bone mineral (BPBM), and guided tissue regeneration (GTR) carried out by Lekovic et al., who reported a slightly greater reduction of PD (4.19 ± 0.81) in the test group (PRP + BPBM + GTR) when compared to 3.98 ± 1.02 in the control group (PRP + BPBM) implying that GTR adds no clinical benefit to PRP + BPBM. Okuda et al. reported that the test group (PRP + HA) exhibited statistically significant changes compared to the control sites (HA alone) which differ from the results of the present study due to a longer duration of evaluation, although the mean PD reduction of both groups was comparable to the present study.
The mean gain in the clinical attachment levels was greater in the experimental group than the control group 6 months posttreatment. On comparing the two groups, the results were found insignificant during any of the time intervals. The explanation for slightly higher mean gain in CAL for PRP + HA could be the potential of PRP to contribute in tissue healing. Arikan et al. and Cáceres et al. suggested the ability of PRP to stimulate gingival fibroblast and to modulate several cell responses potentially involved in wound healing such as cell adhesion, cell migration, and myofibroblastic differentiation. The results of this study are comparable with the studies of Yilmaz et al. and Demir et al.
The amount of gingival recession increased with time in both the groups; however, it was higher in the control group and was statistically not significant between the two groups at 6 months (P = 0.34). The results of the present study are in conformity with the results of the study carried out by Kaushick et al., who reported no significant change in the levels of gingival margin between the groups at the end of 6 months. Following periodontal therapy, the reduction in the probing depth was due to a combination of gingival recession and gain in the attachment levels. Hence, the levels of the gingival margins were not significant.
The defect fill from baseline to 3 months was greater in the experimental group than in the control group with a significant difference on the intergroup comparison. This can be interpreted as an increased remodeling of the graft due to addition of PRP which delivers a highly concentrated source of autologous platelets containing a variety of biological mediators and improves the handling properties of the graft material with which it is combined, facilitating graft placement and stability. The bone gain by PRP + HA observed in this study is in accordance with that of Marx et al., who reported that the addition of PRP to grafts evidenced a radiographic maturation rate 1.62–2.16 times that of grafts without PRP. In the present study, there was no significant difference between the groups at the end of 6 months. The results are in accordance with the results of Okuda et al., who observed no statistical difference in the mean radiographic intrabony defect gain between the PRP + HA group and saline + HA group at 12 months although better results were seen in the test group (PRP + HA was 70% and saline + HA was 56%). These findings were explained by the fact that both treatments have the ability to retain HA granules in intrabony defects for a period of 12 months or longer, suggesting a longer period of monitoring to determine whether the end result is true regeneration rather than repair. Defect resolution following bone grafting can be a result of connective tissue encapsulation of the graft and the long junctional epithelium formation or because of remodeling of the graft and replacement by host bone. The varying results from different studies may be derived from the use of different graft materials, the varying morphology of the initial defects, and/or study designs.
The explanations of the reason for the lack of additive effect of PRP will be speculative due to the limitations of the present study which were small sample size, shorter follow-up period, absence of re-entry, and histological examination. Furthermore, the potential mechanisms of PRP for bone formation were not tested. No blood parameters were evaluated which might have led to the production of PRP with low platelet counts.
| Conclusion|| |
Both treatment modalities demonstrated a significant improvement in the probing depth, clinical attachment level, and radiographic size of the defect at 6 months. Within the limitations of the current study, it can be concluded that PRP addition to a bone graft in the treatment of periodontal intrabony osseous defects shows improved defect fill as compared to the use of bone graft alone. The synergistic effect of PRP is safe and effective in treatment of periodontal intrabony osseous defects. However, long-term clinical trials with larger sample size are needed to evaluate the individual role of PRP along with the regenerative potential when used in combination with bone substitutes.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Sunitha J, Manjunath K. A combination of platelet rich plasma and hydroxyapatite (osteogen) bone graft in the treatment of intrabony defects – A case report: A preliminary study. J Clin Diagn Res 2010;15:2984-8.
Arvidson K, Abdallah BM, Applegate LA, Baldini N, Cenni E, Gomez-Barrena E, et al.
Bone regeneration and stem cells. J Cell Mol Med 2011;15:718-46.
Carranza FA, Camargo PM. The periodontal pocket. In: Newman MG, Takei HH, Carranza FA, editors. Carranza's Clinical Periodontology. 9th
ed. Philadelphia: W.B. Saunders and Co.; 2002. p. 336-53.
Reynolds MA, Aichelmann-Reidy ME, Branch-Mays GL. Regeneration of periodontal tissue: Bone replacement grafts. Dent Clin North Am 2010;54:55-71.
Nasr HF, Aichelmann-Reidy ME, Yukna RA. Bone and bone substitutes. Periodontol 2000 1999;19:74-86.
Aichelmann-Reidy ME, Yukna RA. Bone replacement grafts. The bone substitutes. Dent Clin North Am 1998;42:491-503.
Yukna RA. Synthetic bone grafts in periodontics. Periodontol 2000 1993;1:92-9.
Wagner JR. Clinical and histological case study using resorbable hydroxylapatite for the repair of osseous defects prior to endosseous implant surgery. J Oral Implantol 1989;15:186-92.
Plachokova AS, Nikolidakis D, Mulder J, Jansen JA, Creugers NH. Effect of platelet-rich plasma on bone regeneration in dentistry: A systematic review. Clin Oral Implants Res 2008;19:539-45.
Marx RE, Carlson ER, Eichstaedt RM, Schimmele SR, Strauss JE, Georgeff KR, et al.
Platelet-rich plasma: Growth factor enhancement for bone grafts. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1998;85:638-46.
Carlson NE, Roach RB Jr. Platelet-rich plasma: Clinical applications in dentistry. J Am Dent Assoc 2002;133:1383-6.
Alissa R, Esposito M, Horner K, Oliver R. The influence of platelet-rich plasma on the healing of extraction sockets: An explorative randomised clinical trial. Eur J Oral Implantol 2010;3:121-34.
Boyapati L, Wang HL. The role of platelet-rich plasma in sinus augmentation: A critical review. Implant Dent 2006;15:160-70.
Rutkowski JL, Johnson DA, Radio NM, Fennell JW. Platelet rich plasma to facilitate wound healing following tooth extraction. J Oral Implantol 2010;36:11-23.
Wojtowicz A, Chaberek S, Urbanowska E, Ostrowski K. Comparison of efficiency of platelet rich plasma, hematopoieic stem cells and bone marrow in augmentation of mandibular bone defects. N Y State Dent J 2007;73:41-5.
Kumar A, Triveni MG, Mehta DS. Subepithelial connective tissue graft used with platelet-rich plasma in treatment of gingival recession. Dent Update 2012;39:218-20.
Lacoste E, Martineau I, Gagnon G. Platelet concentrates: Effects of calcium and thrombin on endothelial cell proliferation and growth factor release. J Periodontol 2003;74:1498-507.
Rodrigues SV, Acharya AB, Thakur SL. Platelet-rich plasma. A review. N Y State Dent J 2012;78:26-30.
Löe H. The gingival index, the plaque index and the retention index systems. J Periodontol 1967;38:610-6.
Loe H, Silness J. Periodontal disease in pregnancy. I. Prevalence and severity. Acta Odontol Scand 1963;21:533-51.
Camargo PM, Lekovic V, Weinlaender M, Vasilic N, Madzarevic M, Kenney EB, et al.
Platelet-rich plasma and bovine porous bone mineral combined with guided tissue regeneration in the treatment of intrabony defects in humans. J Periodontal Res 2002;37:300-6.
Okuda K, Tai H, Tanabe K, Suzuki H, Sato T, Kawase T, et al.
Platelet-rich plasma combined with a porous hydroxyapatite graft for the treatment of intrabony periodontal defects in humans: A comparative controlled clinical study. J Periodontol 2005;76:890-8.
Subbaiah R, Thomas B. Efficacy of a bioactive alloplast, in the treatment of human periodontal osseous defects-a clinical study. Med Oral Patol Oral Cir Bucal 2011;16:e239-44.
Eickholz P, Hörr T, Klein F, Hassfeld S, Kim TS. Radiographic parameters for prognosis of periodontal healing of infrabony defects: Two different definitions of defect depth. J Periodontol 2004;75:399-407.
Tözüm TF, Demiralp B. Platelet-rich plasma: A promising innovation in dentistry. J Can Dent Assoc 2003;69:664.
Pradeep AR, Pai S, Garg G, Devi P, Shetty SK. A randomized clinical trial of autologous platelet-rich plasma in the treatment of mandibular degree II furcation defects. J Clin Periodontol 2009;36:581-8.
Mellonig JT. Autogenous and allogenic grafts in periodontal therapy. Crit Rev Oral Biol Med 1992;3:333-52.
Stahl SS, Froum SJ. Histologic and clinical responses to porous hydroxylapatite implants in human periodontal defects. Three to twelve months postimplantation. J Periodontol 1987;58:689-95.
Meffert RM, Thomas JR, Hamilton KM, Brownstein CN. Hydroxylapatite as an alloplastic graft in the treatment of human periodontal osseous defects. J Periodontol 1985;56:63-73.
Sculean A, Jepsen S. Biomaterials for the reconstructive treatment of periodontal intrabony defects. Perio 2004;1:5-15.
Weibrich G, Kleis WK. Curasan PRP kit vs. PCCS PRP system. Collection efficiency and platelet counts of two different methods for the preparation of platelet-rich plasma. Clin Oral Implants Res 2002;13:437-43.
de Obarrio JJ, Araúz-Dutari JI, Chamberlain TM, Croston A. The use of autologous growth factors in periodontal surgical therapy: Platelet gel biotechnology – case reports. Int J Periodontics Restorative Dent 2000;20:486-97.
Hanna R, Trejo PM, Weltman RL. Treatment of intrabony defects with bovine-derived xenograft alone and in combination with platelet-rich plasma: A randomized clinical trial. J Periodontol 2004;75:1668-77.
Blumenthal NM. The effect of supracrestal tricalcium phosphate ceramic-microfibrillar collagen grafting on postsurgical soft tissue levels. J Periodontol 1988;59:18-22.
Strub JR, Gaberthüel TW, Firestone AR. Comparison of tricalcium phosphate and frozen allogenic bone implants in man. J Periodontol 1979;50:624-9.
Lekovic V, Camargo PM, Weinlaender M, Vasilic N, Kenney EB. Comparison of platelet-rich plasma, bovine porous bone mineral, and guided tissue regeneration versus platelet-rich plasma and bovine porous bone mineral in the treatment of intrabony defects: A reentry study. J Periodontol 2002;73:198-205.
Arikan F, Becerik S, Sonmez S, Gurhan I. Effect of platelet-rich plasma on gingival and periodontal ligament fibroblasts: New in-vitro
growth assay. Braz J Oral Sci 2007;6:1432-7.
Cáceres M, Hidalgo R, Sanz A, Martínez J, Riera P, Smith PC, et al.
Effect of platelet-rich plasma on cell adhesion, cell migration, and myofibroblastic differentiation in human gingival fibroblasts. J Periodontol 2008;79:714-20.
Yilmaz S, Cakar G, Ipci SD, Kuru B, Yildirim B. Regenerative treatment with platelet-rich plasma combined with a bovine-derived xenograft in smokers and non-smokers: 12-month clinical and radiographic results. J Clin Periodontol 2010;37:80-7.
Demir B, Sengün D, Berberoğlu A. Clinical evaluation of platelet-rich plasma and bioactive glass in the treatment of intra-bony defects. J Clin Periodontol 2007;34:709-15.
Kaushick BT, Jayakumar ND, Padmalatha O, Varghese S. Treatment of human periodontal infrabony defects with hydroxyapatite + β tricalcium phosphate bone graft alone and in combination with platelet rich plasma: A randomized clinical trial. Indian J Dent Res 2011;22:505-10.
] [Full text]
[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3]