1. Treatment of Intrabony Defects With Bovine-Derived Xenograft Alone and in Combination With Platelet-Rich Plasma: A Randomized Clinical Trial Journal of Peridontology. 2004 Dec;75(12):1668-77
BACKGROUND: In the treatment of periodontal intrabony defects, the benefits of adding platelet-rich plasma (PRP) to a bone replacement grafting material have not been tested. The purpose of this study was to compare the clinical outcomes obtained by the combination of PRP and a bovine derived xenograft (BDX) to those obtained from the use of the bone replacement graft alone.
METHODS: Thirteen patients were enrolled in a randomized, split mouth, double-masked clinical trial. Bilateral defects were matched according to their intrasurgical measurements. Qualifying defects had loss of attachment of > or = 6 mm, a radiographically detectable defect of > or = 4 mm, at least two remaining osseous walls, and not primarily related to a furcation involvement. After the hygienic phase, at the baseline examination, probing depth (PD), clinical attachment level (CAL), and recession (REC) were measured. During open flap debridement, the defects were randomly assigned to receive either BDX mixed with PRP or BDX alone. Baseline osseous intrasurgical measurements were obtained. Post-surgical follow-up and maintenance were performed and PD, CAL, and REC were remeasured at 6 months. The mean baseline and 6-month PD, CAL, and REC of the deepest buccal and lingual measurements related to the defect for each group were computed. The change from baseline to 6 months for each parameter measured was calculated. Pre- and postoperative comparisons were made between treatment groups at 6 months.
RESULTS: Randomization of the defects resulted in comparable groups (P > or = 0.05). At 6 months, paired t test comparisons within groups showed statistically significant benefits with both treatment modalities (P < or = 0.05). The mean changes (delta) at 6 months for the test and the control groups at the deepest sites were: PD reduction: 3.54 and 2.53 mm; CAL gain: 3.15 and 2.31 mm; and REC: -0.38 and -0.23 mm, respectively. Paired t test comparisons yielded significant differences between treatments for PD and CAL (P < or = 0.05).
CONCLUSION: In this 6-month clinical trial, the addition of a high concentration of autologous platelets to a bovine derived xenograft to treat intrabony defects significantly improved their clinical periodontal response.
2. 2. Platelet-Rich Plasma Influence on Human Osteoblasts Growth
Clinical oral implants research. 2005 Aug;16(4):456-60
Objective: The influence of progressively high concentrations of platelet-rich plasma (PRP) on human osteoblast hFOB1.19 proliferation was evaluated.
Material and methods: The PRP was obtained from a human source. Two experiments were conducted. In the first one, PRP was diluted to 50%, 25%, 12.5% and 6.125% (v/v) with culture medium (Modified Eagle’s Medium (MEM) : Ham’s F12 Medium (HAM-F12%) and 1% antibiotics-antimicotic) supplemented with 10% of fetal bovine serum (FBS). In the second experiment, all conditions were identical except for the absence of FBS in the culture medium.
Results: The results of the osteoblast proliferation test were higher when stimulated by the 50% PRP dilution, with or without FBS. A further study is suggested to determine if concentrations above 50% could cause higher rates of osteoblast proliferation. In this study, the results were not statistically different (P<0.05) with 12.5% and 6.125% PRP dilutions. Additionally, it was shown that FBS is not necessary for PRP-mediated induction of osteoblast proliferation.
Conclusion: This study concluded that PRP promotes osteoblast proliferation and suggested its clinical application to bone graft procedures in implant dentistry.
3. 3. Platelet-Rich Plasma Combined With a Porous Hydroxyapatite Graft for the Treatment of Intrabony Periodontal Defects in Humans: A Comparative Controlled Clinical Study Journal of Peridontology. 2005 Jun;76(6):890-8
BACKGROUND: The aim of the present controlled clinical study was to compare platelet-rich plasma (PRP) combined with a biodegradable ceramic, porous hydroxyapatite (HA) with a mixture of HA and saline in the treatment of human intrabony defects.
METHODS: Seventy interproximal intrabony osseous defects in 70 healthy, non-smoking subjects diagnosed with chronic periodontitis were included in this study. Thirty-five subjects each were randomly assigned to either the test group (PRP and HA) or control group (HA with saline). Clinical and radiographic measurements were determined at baseline and the 12-month evaluation.
RESULTS: When compared to baseline, the 12-month results indicated that, while both treatment modalities resulted in significant changes in all clinical parameters (gingival index, bleeding on probing, probing depth, clinical attachment level, and intrabony defect fill; P <0.001), the test group exhibited statistically significant changes compared to the control sites in probing depth reduction: 4.7 +/- 1.6 mm versus 3.7 +/- 2.0 mm (P <0.05); clinical attachment gain: 3.4 +/- 1.7 mm versus 2.0 +/- 1.2 mm (P <0.001); and vertical relative attachment gain: 70.3% +/- 23.4% versus 45.5% +/- 29.4% (P <0.001).
CONCLUSION: Treatment with a combination of PRP and HA compared to HA with saline led to a significantly more favorable clinical improvement in intrabony periodontal defects.
4. Platelet-rich plasma: A preliminary report in routine impacted mandibular third molar surgery and the prevention of alveolar osteitis
Journal of Oral and Maxillofacial Surgery, Volume 61, Number 8, Supplement 1, August 2003
Jerome D. Mancuso, J.W. Bennion, M.J. Hull, B.W. Winterholler
Purpose: One hundred seventeen patients undergoing elective impacted mandibular third molar removal were enrolled in the study. Median age was 17.2 with a range from 14 to 22. There were 68 males and 49 females, and all females were questioned regarding use of oral contraceptives, the use of which precluded enrollment in the study. Also, the use of tobacco in any form resulted in removal from the study. Inclusive study dates were July 2002 to December 2002.
Patients and Methods: The 117 patients underwent elective removal of impacted mandibular third molars in the absence of any clinical pericoronitis, infection, or opposing traumatic occlusion. Platelet-rich plasma (PRP) was prepared as described by the manufacturer by collecting 20 cc of autogenous blood at the time of venipuncture, before intravenous fluids or sedative medications were administered. The specimen was centrifuged using the Harvest Technology Prep 2 centrifuge according to manufacturers’ specifications. The platelet concentrate, containing an average of 338% platelets, was then reconstituted with blood plasma and combined with calcium chloride and topical thrombin to form the platelet gel. The PRP was then placed into either position 17 or 32 by the surgeons (J.D.M. and J.W.B) The remaining platelet-poor plasma (PPP) was applied over the suture line on the same side to aid in hemostasis. Follow-up evaluation was performed immediately before discharge from the office, at seven days, fourteen days, and thirty days by two other surgeons (M.J.W. and B.W.W.), and compared to the contralateral side. The evaluating surgeons were unaware which side was treated with the PRP.
Results: The overall rate of alveolar osteitis in the PRP treated site was 3.4% (4 cases) versus the untreated site, which was 12.8% (15 cases), representing an almost four-fold increase. The PRP- and PPP-treated sides showed better hemostasis at time of discharge, faster soft tissue flap healing, decreased swelling seven days postsurgically, and a lower level of pain. One-month follow-up Panelipse radiographs demonstrated more dense bone fill and radiopacity in the extraction site of the PRP-treated side. PRP is an inexpensive and widely available modality to minimize the occurrence of AO and enhance both hard and soft tissue healing potentials.
5. Platelet-Rich Plasma: Growth Factor Enhancement for Bone Grafts
Oral Surgery, Oral Medicine, Oral Pathology; 85, 638-646; 1998
R. Marx, E. Carlson, R. Eichtaedt, S. Schimmele, J. Strauss, K. Georgeff
Platelet-rich plasma is an autologous source of platelet-derived growth factor and transforming growth factor beta that is obtained by sequestering and concentrating platelets by gradient density centrifugation. This technique produced a concentration of human platelets of 338% and identified platelet-derived growth factor and transforming growth factor beta within them. Monoclonal antibody assessment of cancellous cellular marrow grafts demonstrated cells that were capable of responding to the growth factors by bearing cell membrane receptors. The additional amounts of these growth factors obtained by adding platelet-rich plasma to grafts evidenced a radiographic maturation rate 1.62 to 2.16 times that of grafts without platelet-rich plasma. As assessed by histomorphometry, there was also a greater bone density in grafts in which platelet-rich plasma was added (74.0% +/- 11%) than in grafts in which platelet-rich plasma was not added (55.1% +/- 8%; p = 0.005).
- The results of the radiographic and histomorphometric studies suggested that Platelet Rich Plasma addition to graft material accelerated the rate of bone formation and the degree of bone formation at least through the first 6 months.
- Furthermore these studies showed that cancellous marrow grafts contain cells bearing PDGF and TGF-B receptors as the probable targets of Platelet Rich Plasma, as well as being intimately involved in the bone regeneration process.
- A threefold or greater concentration of platelets, as was measured in Platelet Rich Plasma can be expected to have a profound effect on wound healing enhancement and bone regeneration.
- In this study it was shown that platelet Rich plasma contains a concentration of platelets and a concentration of growth factors. Our study presented evidence that these growth factor additions to bone grafts produced a quantifiably enhanced result in comparison with grafts performed without its use.