|Year : 2017 | Volume
| Issue : 1 | Page : 33-40
Clinical evaluation of platelet rich plasma when combined with an alloplastic bone graft material in the treatment of intrabony periodontal defects
Kapil Garg1, Ruchi Srivastava2, Pushpendra Kumar Verma3, Anju Gautam4, Vivek Tripathi1, Satyendra Agarwal5
1 Department of Periodontics, Azamgarh Dental College, Azamgarh, Uttar Pradesh, India
2 Department of Periodontics, Saraswati Dental College, Lucknow, Uttar Pradesh, India
3 Department of Conservative Dentistry and Endodontics, Saraswati Dental College, Lucknow, Uttar Pradesh, India
4 Department of Periodontics, Faculty of Dental Sciences, IMS, BHU, Varanasi, Uttar Pradesh, India
5 Department of Conservative Dentistry and Endodontics, K.D. Dental College, Mathura, Uttar Pradesh, India
|Date of Web Publication||14-Feb-2017|
Department of Periodontics, Azamgarh Dental College, Azamgarh, Uttar Pradesh
Source of Support: None, Conflict of Interest: None
Introduction: For periodontal regeneration, various modalities are available; among these,use of growth factors is a developing area for clinicians and researchers, as they stimulate cells responsible for periodontal regeneration. Growth factor is a general term used to denote a class of naturally occurring proteins that function in the body to promote the mitogenesis (proliferation), directed migration, and metabolic activity of cells. Platelet-rich plasma (PRP) is a new application and is a storage vehicle for growth factors, especially platelet-derived growth factor and transforming growth factor-b both of which influence bone regeneration.
Aim: The aim of this study was to examine the clinical efficacy of autologous PRP combined with an alloplastic bone graft material (hydroxyapatite and β-tricalcium phosphate [HA/β-TCP], (Ossifi™)) in the treatment of three-wall intrabony periodontal defects.
Materials and Methods: Twenty-four patients (15 females and 9 males with age ranging from 28 years to 47 years) with moderate to advanced chronic periodontitis with three-wall intrabony defects were selected for the study. All patients were divided into two groups, i.e., “Group-I” and “Group-II;” 12 patients in each group. “Group-I” was control group with patients treated with HA/β-TCP with saline and “Group-II” was test group entitled to patients who were treated with PRP + HA/β-TCP. Clinical parameters recorded were bleeding on probing, probing depth, and clinical attachment level. Furthermore, the radiographic parameters included depth of intrabony defects, calculated as the difference of distances between cementoenamel junction (CEJ) to the bony defect and CEJ to the alveolar crest.
Results and Conclusion: Combination of PRP with alloplastic bone graft material, i.e., test Group-II (PRP + HA/β-TCP), showed a better result than control Group-I (saline + HA/β-TCP) in the treatment of intrabony defects.
Keywords: Alloplastic bone graft, growth factors, intrabony defects, platelet-rich plasma
|How to cite this article:|
Garg K, Srivastava R, Verma PK, Gautam A, Tripathi V, Agarwal S. Clinical evaluation of platelet rich plasma when combined with an alloplastic bone graft material in the treatment of intrabony periodontal defects. Saudi J Oral Sci 2017;4:33-40
|How to cite this URL:|
Garg K, Srivastava R, Verma PK, Gautam A, Tripathi V, Agarwal S. Clinical evaluation of platelet rich plasma when combined with an alloplastic bone graft material in the treatment of intrabony periodontal defects. Saudi J Oral Sci [serial online] 2017 [cited 2019 Oct 14];4:33-40. Available from: http://www.saudijos.org/text.asp?2017/4/1/33/200139
| Introduction|| |
Periodontal regeneration can be defined as regeneration of the tooth's supporting tissues, including alveolar bone, periodontal ligament, and cementum over a diseased root surface. The ultimate goal of periodontal therapy is to regenerate the lost periodontal tissues for optimal function and esthetics. The current therapeutic modalities for periodontal regeneration include the use of bone grafts, guided tissue regeneration (GTR) using barrier membranes, coronally advanced flaps, and enamel matrix proteins. Among these, GTR has been the most promising, as it provides a space for the migration of the periodontal ligament cells and prevents the formation of long junctional epithelium. However, what is lacking in this procedure is the induction and differentiation of cells responsible for periodontal regeneration. To bridge this gap, application of growth factors or biological response molecules, to stimulate cells, responsible for periodontal regeneration was proposed. Growth factor is a general term used to denote a class of naturally occurring proteins that function in the body to promote mitogenesis (proliferation), directed migration, and metabolic activity of cells. Growth factors act at very low concentrations; this may modulate cellular behaviors such as proliferation and differentiation or production of other growth factors. Growth factors are important at all stages of the cell cycle and may stimulate chemotaxis and production of extracellular matrix products.
Platelet-rich plasma (PRP) is an autologous source of platelet-derived growth factors (PDGFs) and transforming growth factors and is obtained by sequestering and concentrating platelets by centrifugation. The patient's own blood is withdrawn and separated into its three basic components, i.e., PRP, platelet-poor plasma (PPP), erythrocytes, and leukocytes. The PRP contains a high mixture of platelets and a concentration of growth factors. PRP has been used in various surgical fields, including head and neck surgery, otolaryngology, cardiovascular surgery, oral and maxillofacial surgery, and periodontics.
One major criterion for periodontal regeneration is the maintenance of a wound space for periodontal ligament cells to migrate into. Hence, for growth factors to exert their potential, they require a medium that can provide this space. Thus, by combining a bone graft with PRP in wound space, cell induction and differentiation can be obtained. The possibility of using autologous PRP along with bone grafting procedures wasfirst explored by Marx et al., where he showed that the bone maturation increased by 1.62–2.16 times when compared to bone grafts alone at 6-month postoperative, as measured by histomorphometry. According to Wiltfang et al., β-tricalcium phosphate has been shown to combine well with PRP, and when used to augment bone, it was observed that formation of new bone was about 8–10% higher as compared to β-tricalcium phosphate alone. The purpose of this study was to determine the clinical effectiveness of autologous PRP when combined with an alloplastic bone graft material (hydroxyapatite and β-tricalcium phosphate [HA/β-TCP], (Ossifi™)) with a mixture of HA/β-TCP with saline in the treatment of intrabony periodontal defects.
| Materials and Methods|| |
Twenty-four patients (15 females and 9 males with age ranging from 28 years to 47 years) with moderate to advanced chronic periodontitis were recruited from the outpatient department of periodontics. Twelve patients were assigned to each group: test and control study groups. All patients were divided into two groups, i.e. “Group-I” and “Group-II.” “Group-I” was control group for patients who were treated with HA/β-TCP with saline and “Group-II” was test group for patients who were treated with PRP + HA/β-TCP. All patients were informed about the procedure being performed and their consent was obtained. The patients were included based on good general health with no history of allergy, presence of moderate to severe periodontitis, presence of three-wall intrabony defect with a probing depth (PD) >5 mm and clinical attachment loss (CAL) >5 mm with radiographic angular defect depth >3 mm, located in the interproximal area. Standardized parallel cone technique with grid mount was used to take radiographs. Medically compromised patients, smokers, generalized aggressive periodontitis, pregnant and lactating women, and teeth with Grade III mobility and hopeless prognosis were excluded from the study.
Initial therapy consisted of oral hygiene instructions and thorough full mouth scaling, and root planing was performed. Four weeks following Phase I therapy, reevaluation was performed to confirm the suitability for this periodontal surgical study. Patients who met all criteria for entry into surgical phase of the study were then randomized to “test Group-I” (PRP + HA and β-TCP) and “control Group-II” (saline + HA and β-TCP).
Presurgical clinical measurements
A periodontal probe was inserted into the pocket using an occlusal stent. Bleeding on probing, PD, and clinical attachment level (CAL) were recorded [Figure 1]. Measurements were performed with a University of North Carolina Probe (UNC-15).
After initial therapy, standardized reproducible intraoral periapical radiographs with positioning aids were taken, with the KKD ™ XCP System (Germany). Radiographs were taken at baseline and 6 months postoperatively. The following landmarks were identified on the radiographs:,
- Cementoenamel junction (CEJ): if the CEJ was destroyed by restorative treatment, the margin of the restoration was taken as landmark
- Base of the defect (BD) was defined as the most coronal point where the periodontal ligament space showed a continuous width
- Alveolar crest (AC) was defined as the point of crossing of the silhouette of the AC with the root surface.
The depth of the intrabony component of the defect was calculated using grid mount [Figure 2] as the difference of the distances between the CEJ to the bony defect and CEJ to the AC.
Intrabony defect = [CEJ to BD] − [CEJ to AC].
Preparation of platelet-rich plasma
PRP was prepared from the patient's blood through modified Curasan method. One hour before surgery, 8 ml of blood was drawn from the patient by venipuncture of the antecubital vein. Blood was collected into vacutainers containing 3.2% sodium citrate solution as an anticoagulant. The vacutainers containing the blood were centrifuged at 2400 rpm for 10 min, which resulted in the separation of two basic fractions, the erythrocyte fraction and the plasma fraction containing the platelets, which is the supernatant fluid [Figure 3]. The plasma fraction was then pipetted out and centrifuged again at 3600 rpm for 15 min, which resulted again in two fractions, PRP and PPP, which is the supernatant fluid. PRP is pipetted out and placed in a petri dish [Figure 4]. The PRP was stored at − 20°C until used.
The surgical procedure was performed under local anesthesia of 2% lignocaine containing adrenaline at a concentration of 1:100,000. A mucoperiosteal flap was elevated with sulcular incisions. Complete debridement of the defect as well as scaling and root planing was achieved. The defects were packed with alloplastic bone graft material, HA/β-TCP granules (particle size 0.25–1 mm, Ossifi™, Equinox Medical Technologies, Holland, America) mixed with the coagulated PRP preparation in a proportion of 1:1 up to the level of the surrounding bony walls [Figure 5]. Care was taken not to overfill the defect. The flaps were then approximated and sutured at the original level using 3-0 silk with an interrupted horizontal mattress technique [Figure 6]. Periodontal dressing was placed over the area for 1 week. Antibiotics (amoxicillin 500 mg, every 8 h for 5 days), analgesics (ibuprofen 400 mg every 8 h for 5 days), and 0.2% chlorhexidine gluconate rinses (every 12 h for 2 weeks) were prescribed. Patients were recalled after 1 week to reevaluate the surgerized area and for suture removal. Patients were monitored on weekly schedule postoperatively, to ensure good oral hygiene. At the end of 6 months, the patients were examined again for all the clinical parameters [Figure 7]. At 6-month recall, the tooth was asymptomatic with successful healing, and the follow-up radiograph showed evidence of apparent bone fill with a resolution of the osseous defect [Figure 8] and [Figure 9]. Similarly, the surgical procedure was carried out for the control Group-I (saline + HA/β-TCP) without PRP. The pre- and post-surgical radiographs are shown in [Figure 10] and [Figure 11].
Results were averaged out (mean ± standard error) for each parameter. The net difference between each pair of measurements was then calculated (pre- and post-operative). Student's paired t-test was used to compare the differences. Student's t-test was applied to correlate and compare the data in two different sets of samples to find out the significance of difference in their means and P < 0.05 was considered statistically significant.
| Results|| |
The comparison of baseline indices and measurements of Group-I and Group-II is presented in [Graph 1]. Comparison of postoperative indices and measurements of Group-I and Group-II is presented in [Graph 2].
Graph 1 reveals that the mean bleeding probing index was found to be 0.667 ± 0.778 for Group-I and 0.583 ± 0.793 for Group-II. Statistically, there was no significant difference between the two groups. The mean PD was recorded as 7.333 ± 1.073 mm for Group-I and 7.500 ± 1.000 mm for Group-II. The mean CAL was measured as 7.250 ± 1.055 mm for Group-I and 7.583 ± 0.515 mm for Group-II. The mean distance between CEJ and BD was 8.000 ± 1.206 mm in Group-I and 8.417 ± 1.832 mm in Group-II while the mean distance between CEJ and AC was 3.500 ± 1.087 mm in Group-I and 3.167 ± 1.115 mm in Group-II. The mean intrabony defect was recorded as 4.500 ± 0.905 mm in Group-I and 5.250 ± 1.913 mm in Group-II. Statistically, there was no significant difference between the two groups for any of the baseline indices. The groups were thus matched.
Graph 2 reveals that group-wise the mean bleeding probing index was found to be 0.250 ± 0.452 for Group-I and 0.167 ± 0.389 for Group-II. Statistically, there was no significant difference between the two groups. The mean PD was recorded as 4.000 ± 0.603 mm for Group-I and 3.333 ± 0.651 mm for Group-II. The mean CAL was measured as 4.250 ± 0.866 mm for Group-I and 3.583 ± 0.669 mm for Group–II, thus showing a statistically significant difference between the two groups, both for PD as well as CAL. The mean distance between CEJ and BD was 5.000 ± 1.706 mm in Group-I and 4.417 ± 1.929 mm in Group-II while the mean distance between CEJ and AC was 3.250 ± 1.055 mm in Group-I and 2.833 ± 1.193 mm in Group-II. The mean intrabony defect was recorded as 1.750 ± 0.429 mm in Group-I and 1.667 ± 2.229 mm in Group-II. Statistically, there was no significant difference between the two groups for any of the hard tissue measurements.
The test Group-II (PRP + HA/β-TCP) showed a mean reduction in PD of 4.16 mm, CAL gain of 3.9 mm, and defect fill of 3.6 mm and the control Group-I (saline + HA/β-TCP) showed a mean reduction in PD of 3.33 mm, CAL gain of 3.0 mm, and defect fill of 2.7 mm. Hence, the results of the test Group-II (PRP + HA/β-TCP) were statistically significant than the control Group-I (Saline + HA/β-TCP).
| Discussion|| |
Regenerative therapy strengthens the fabric of our teeth. They contribute to strong and healthy periodontal support. The use of growth factors for periodontal regeneration has recently attracted the attention of periodontal researchers and clinicians., Growth factors are produced locally, have paracrine or autocrine effects, and appear to play a significant role in wound healing. They exert their effects by binding to high-affinity cell membrane receptors, resulting in the activation of second messenger pathways and gene activation. PGFs are the biological mediators that have the ability to regulate cell proliferation, chemotaxis, and differentiation. PDGF is stored in bone matrix  and released on the activation of osteoblasts, resulting in an increase of new bone formation. Thus, it is generally accepted that PDGF function as an anabolic factor in bone metabolism. Transforming growth factor-b (TGF-b) is also found at higher levels in bone matrix and on activation facilitates wound healing under inflammatory conditions. It also stimulates the proliferation of gingival fibroblastic cells, the formation of blood vessels, and the remodeling of extracellular matrix which resulted in increased formation of granulation tissue within the healing periodontal tissues. PDGF and TGF-b are known to be abundant in alpha granules of platelets. A convenient or economical approach to obtain autologous PDGF and TGF-b is the use of PRP. The present study, therefore, envisaged to determine the efficacy of combining PRP with hydroxyapatite and β-tricalcium phosphate (Ossfi™, Equinox Medical Technologies, Holland) in the treatment of periodontal intrabony defects. Biphasic calcium phosphate grafts are advantageous because resorption of β-tricalcium phosphate triggers macrophages, which may affect cell differentiation of soft tissue cells into osteoblasts. The PRP was prepared before the surgical procedure, and when platelet count was randomly checked, the number of platelets was in the range of 500,000–800,000 per cubic mm of plasma. The PRP preparation, due to its high fibrin content, presents with a “sticky” characteristic which works as a hemostatic and stabilizing agent and may aid the blood clot and bone graft immobilization in defect area., This method scores over other techniques of PRP preparation in that it requires minimal blood for preparation (8 ml), is more economical, time for preparation is less, and can be employed in a routine dental setup.
The greater reduction in PD, gain in CAL, and bone defect fill observed in PRP + HA and β-TCP group as compared to saline + HA and β-TCP group in the present study may be explained by additional biological effects of PRP. The adjunctive clinical benefit of the PRP preparation can be explained on the basis of tissue engineering. That is, tissue engineering generally combines three key elements for regeneration: (1) scaffolds or matrices, (2) signaling molecules or growth factors, and (3) cells. By combining these elements under appropriate biological and environmental conditions as well as enough time, tissue regeneration will become more predictable. When this tissue engineering concept becomes applicable to the present method, HA + β-TCP and PRP could become suitable scaffolds and growth factors, respectively. PRP preparations modulate cell proliferation in a cell-type-specific manner, which has shown to potently stimulate PDL cells and osteoblastic proliferation while inhibiting epithelial cell proliferation. In addition, PRP has been shown to form a gel-like material in several cell cultures of either PDL or osteoblastic cells. This gel-like material was shown to be fibrin clots that were capable of upregulating collagen synthesis in the extracellular matrix. Blood clot immobilization has been suggested as an important event in the early phases in wound healing in periodontal regenerative procedures. In a study, the clinical effect of porous particulate hydroxyapatite on human periodontal osseous defect repair was reported with mean PD as 2.9 mm and mean CAL was 1.6 mm after 6 months as compared to baseline.
In the experimental group, a mean reduction in PDs of 4.16 mm was observed while the clinical attachment gain was 3.91 mm and the radiographic bone fill was 3.67 mm which were statistically and clinically significant, which coincided with the findings obtained by Lekovic et al. in which they reported a PD reduction of 4.19 mm, CAL gain of 4.12 mm, and a defect fill of 4.96 mm. Another combination of periodontal therapy using PRP for treating intrabony defects has been reported by Camargo et al. This triple combination therapy was composed of PRP, bovine porous bone mineral, and GTR. Camargo et al. demonstrated a clinical attachment gain in the range of 4.28–4.37 mm and defect fill in the range of 4.66–4.78 mm. The values obtained in our study are slightly lower; the difference in clinical response likely was due to the additional benefits of GTR when used in combination with PRP in their study.
The type of bony defects taken in this study varied from three-walled to two-walled defects, often combined defects. In strictly three-walled defects, bone fill was complete while the others showed partial bone fill. This confirms to the prevalent opinion of clinicians about the number of walls of bony defects that are required to have a better degree of bone fill. It can therefore be concluded that defect configuration plays an important role in the outcome as much as biomechanics of regeneration. It is also pertinent to note here that a maximum number of the regenerative studies have reported bone fill to continue beyond 12 months following surgery. In the present study, results were evaluated up to the end of 6 months following surgery. Hence, if the time was permitted longer for the observation, maybe the results would have been better.
The methods employed for evaluating the results of this study were simple. The clinical measurements were made using the UNC-15 probe. The radiographic measurements were made with the X-ray grid mount. The use of advanced diagnostic techniques such as third-generation periodontal probes and subtraction radiography would have perhaps made it possible for a more accurate estimation of values. However, keeping in view of the ample information available about the properties of PRP and taking cognizance of improvements seen in various clinical parameters seen in this study, it is reasonable to assume that the use of PRP resulted in qualitatively superior healing than using synthetic bone grafts alone.
| Conclusion|| |
Periodontal therapy using a combination of PRP with other bone graft materials has enhanced the outcome of regenerative surgery. Within the limits of the current study, it can be concluded that both a combination of PRP plus HA and β-TCP or saline plus HA and β-TCP bone graft treatment led to significant improvements of investigated clinical parameters. The added benefits of PRP combined with HA and β-TCP are not only of statistical but also of clinical significance. The ease of applying PRP in dental clinic and its beneficial outcomes hold promise for further procedures. Most importantly, this autologous product eliminates concerns about immunogenic reactions and disease transmission.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9], [Figure 10], [Figure 11]