Indian Journal of Research in Homeopathy

ORIGINAL ARTICLE
Year
: 2020  |  Volume : 8  |  Issue : 2  |  Page : 78--85

Clinical evaluation and comparison of platelet-rich fibrin and injectable platelet-rich fibrin (sticky bone) in the treatment of intrabony defects


Eldrida Dsa1, Anirban Chatterjee1, Deepa N Shetty1, AR Pradeep2,  
1 Department of Periodontology, The Oxford Dental College, Bengaluru, Karnataka, India
2 Department of Periodontology, The Oxford Dental College; Department of Periodontology, Government Dental College, Bengaluru, Karnataka, India

Correspondence Address:
Dr. Eldrida Dsa
Department of Periodontology, The Oxford Dental College, 10th Milestone, Hosur Road, Bommanahalli, Bengaluru - 560 068, Karnataka
India

Abstract

Introduction: Periodontal regeneration aims to regenerate the lost periodontium, and platelet concentrates are frequently used in the medical fields to improve the healing and promote tissue regeneration. Objective: The aim of the study was to evaluate the efficacy of injectable platelet-rich fibrin (i-PRF) (sticky bone) in comparison to platelet-rich fibrin (PRF) in the treatment of intrabony defects. Materials and Methods: A total of 54 sites treated were divided into three groups (Group I – open flap debridement [OFD alone], Group II – OFD with i-PRF [sticky bone], and Group III – OFD with PRF) in moderate-to-severe periodontitis. The clinical parameters assessed were plaque index, gingival index, probing pocket depth (PPD), relative attachment level, and defect depth reduction at baseline, 3, 6 and 9 months. Results: Nine months postoperatively, a significant improvement in clinical and radiographic parameters was observed from baseline in all three groups. However, Group II and Group III showed better results in all the parameters compared to Group I. Nine months postoperatively, the defect depth reduction was: OFD - 41.59%, i-PRF - 72.75%. and PRF - 62.11%. Conclusion: PC (i-PRF [sticky bone] and PRF) have shown better clinical and radiographic outcomes than OFD in the treatment of intrabony defects in chronic periodontitis.



How to cite this article:
Dsa E, Chatterjee A, Shetty DN, Pradeep A R. Clinical evaluation and comparison of platelet-rich fibrin and injectable platelet-rich fibrin (sticky bone) in the treatment of intrabony defects.Niger J Exp Clin Biosci 2020;8:78-85


How to cite this URL:
Dsa E, Chatterjee A, Shetty DN, Pradeep A R. Clinical evaluation and comparison of platelet-rich fibrin and injectable platelet-rich fibrin (sticky bone) in the treatment of intrabony defects. Niger J Exp Clin Biosci [serial online] 2020 [cited 2021 Apr 17 ];8:78-85
Available from: https://www.njecbonline.org/text.asp?2020/8/2/78/309166


Full Text



 Introduction



Periodontium is a specialized tissue that surrounds and supports the teeth in the jaws. Periodontium may be affected by microorganisms along with the host response, resulting in destruction of the periodontal ligament and alveolar bone. Periodontitis is not necessarily a progressive destruction; there are usually periods of exacerbation and remission. Periodontal osseous lesions represent the anatomical sequelae to the apical spread of periodontitis.[1] Various surgical techniques have been used to achieve the ideal biologic conditions required for periodontal regeneration, open-flap debridement (OFD) was among the earliest procedures used, and studies have reported successful treatment outcome in the management of intrabony defects using OFD, while it offers only limited potential toward recovering the lost periodontal structures. Hence, a broad range of treatment options such as barrier membranes, autografts, demineralized freeze-dried bone allografts, xenografts, combinations of membranes, and fillers have been explored for their ability to predictably regenerate the periodontium.[2]

Platelet concentrates (PC) are frequently used for surgical procedures in many medical fields, and the objective of these technologies is to extract (through centrifugation) all the elements from a blood sample that could be useful to improve healing and promote tissue regeneration.[3] Platelet-rich fibrin (PRF) was first developed by Dohan et al. for use in oral and maxillofacial surgery, which requires neither anticoagulant nor bovine thrombin. In the fibrin meshes, platelets are trapped and the success of this technique entirely depends on the speed of blood collection and transfer to the centrifuge.[4] In a study conducted to investigate effectiveness of autologous PRF, in the treatment of 32 intrabony defects of chronic periodontitis, participants were followed up for 9 months. The study concluded that, there was greater reduction in PD, CAL gain and greater intrabony defect fill at sites treated with autologous PRF as compared to OFD treatment alone.[5]

Injectable PRF (i PRF) is a PC in the liquid form that can be polymerized with bone graft. i PRF being autogenous, decreases the chances of adverse reaction to the implanted materials, especially immune mediated ones as with other type of grafts, which qualify it as a viable option in bone regeneration. i-PRF permits the incorporation of graft without the use of anticoagulants or additives, thereby forming a well-agglutinated “Steak for bone grafting.”[6]

The present study was undertaken with the objective of evaluating the efficacy of i-PRF (sticky bone) in comparison to PRF along with OFD in the treatment of intrabony defects in chronic periodontitis, correlating with the clinical and radiographic parameters.

 Materials and Methods



Participants who visited the Department of Periodontology, The Oxford Dental College, Bommanahalli, Hosur Road, Bangalore, India, were included in the study. Participants with moderate (probing depth of 5–7 mm with clinical attachment loss of 3–4 mm) to severe (probing depth of >7 mm with clinical attachment loss of >5 mm) chronic periodontitis (Update 1999 Classification (Task force Report 2015)[7] who fulfilled the inclusion criteria were randomly assigned into three groups. Sample size was determined based on the power analysis at confidence interval of 90% (P = 0.05). The study procedure was explained in detail to the participants, and written informed consent was obtained before including them in the study. The ethical clearance was obtained from the Institutional Committee and Review Board of The Oxford Dental College Bangalore, India (Ref. No: 258/2017-18). The study was conducted in accordance with the Helsinki Declaration, 1975.

Initially, 19 participants were selected for the study with 61 intrabony defects sites which were distributed, i.e., 20 intrabony defects to Group I, 21 intrabony defects in Group II, and 20 intrabony defects to Group III. However, due to the drop of two participants during the follow-up visits, thus, at the end of 9 months, 17 participants with 57 sites were included in the study.

The participants were divided into three groups. Group I: 18 intrabony defects were treated using OFD alone. Group II: 21 intrabony defects were treated using OFD + i-PRF (sticky bone). Group III: 18 intrabony defects were treated using OFD + autologous PRF. Based on Goldman and Cohen[8] 1958 classification, either three-walled or two-walled defects were considered. Each participant was assigned based on the number of sites present. The sites were randomly divided using the Chit system, and one of the investigators did the allocation into groups. The investigators involved in determining the results and statistical analysis were blinded.

The inclusion criteria included participants with age group 20–55 years with a minimum of 20 permanent teeth.[9] Probing pocket depth of ≥5 mm after Phase I periodontal therapy and presence of intrabony defects in Chronic periodontitis subjects.[7] Complete blood count in the normal range (platelet count: 150,000 s 450,000/ml of blood). While, the exclusion criteria included Systemically compromised patients and those on medications (corticosteroids/bisphosphonate, statin therapy/antiplatelet drugs or blood thinners), Grade II and Grade III tooth mobility, Grade III furcation, tobacco and alcohol users, Pregnant and lactating women, participants who have undergone periodontal treatment within a period of past 1 year.

Clinical parameters to be assessed

Gingival index (GI),[10] plaque index (PI),[11] pocket probing depth (PPD), and relative attachment level (RAL) using manual University of North Carolina-15 Probe (Hu-Friedy, Chicago, IL, USA) were assessed. A full-mouth scaling and root planing procedure was performed after initial examination. Re-evaluation was done after 1 week, and if the tissue response was satisfactory, the patient was scheduled for surgery after 4 weeks.

Stent preparation

Before surgery, study casts were prepared and customized acrylic stents which covered the occlusal surfaces of the teeth involved were fabricated for each subject and stored on the cast itself. An occlusoapical groove in the stent was made to standardize the insertion of the probe and to be used as a fixed reference point for vertical furcation defects measurement.

Case history was recorded. Clinical parameters were assessed at baseline and 3, 6, and 9 months.

Radiographic assessment

Radiographic assessment was carried out using orthopantomography at baseline and 9 months to evaluate the type and extent of bony defects associated with each tooth and radiovisiography to determine the bone defect associated with each site involved at baseline, during surgical procedure after placement of the regenerative material, and 3, 6, and 9 months to determine the defect depth reduction. It was subjected to analysis using Autodesk AutoCAD 2013 Version software.

The measurement of osseous defect was done using intraoral periapical radiographs of each defect site exposed at baseline and 9 months using long cone/paralleling technique.

The percentage of bone fill was calculated by the formula:[12]

[INLINE:1]

RBL is the radiographic bone level (distance between furcation fornix and base of the defect).

Preparation of injectable platelet-rich fibrin (sticky bone)

The i-PRF was prepared following the protocol developed by Mourão et al.[6],[13] 10 ml of venous blood from the participants was drawn under aseptic conditions by venipuncture of the antecubital vein and transferred into an i-PRF sterile test tube (Labtech Disposable, Gandhinagar, Gujarat, India). The test tubes were centrifuged at 700 rpm for 3 min. The orange-colored fluid that was formed above i.e., i-PRF, 1 ml of it was collected in a syringe. Bone graft particles (PerioGlas®) were placed in a sterile steel bowl, and i-PRF was added to the bone graft particles. Within 15 min polymerization started and at the end of 20 min, sticky bone was ready to be grafted.

Preparation of platelet-rich fibrin

PRF was prepared following the protocol in an earlier study by Pradeep et al.[14] 10 ml of venous blood from the participants was drawn under aseptic conditions by venipuncture of the antecubital vein in a 10 ml sterile test tube for PRF.

Blood was centrifuged on a table top centrifuge (R4C, REMI laboratory instruments Goregoan East, Mumbai, India) at 3000 rpm for 10 min (405 g) to obtain autologous PRF layer between a base of red blood cells (RBCs) at the bottom and acellular plasma on the surface. Surface acellular plasma was separated by pipetting 2–3 ml of the top layer and the RBC layer was removed/cut and the PRF was placed in a sterile Dappen dish.

Surgical procedure

Profound local anesthesia, i.e., 2% lignocaine with 1: 100,000 adrenaline, was delivered to the area of surgery. Group I site was treated using OFD which included an intrasulcular incision, the elevation of full-thickness mucoperiosteal flap with a periosteal elevator and debridement of the defect was done using Gracey curettes (Gracey, Hu-Friedy, Chicago, IL, USA). The mucoperiosteal flap was repositioned using 3-0 nonabsorbable silk (Ethicon, Johnson and Johnson Ltd., Somerville, NJ, USA) surgical suture with simple interrupted suturing technique. The Group II sites were treated using OFD followed by placement of sticky bone (i-PRF) in the defect. Similarly, the Group III sites were treated using OFD followed by the placement of PRF in the defects. Each site was covered with periodontal dressing (Coe-Pak, GC America Inc., Chicago, IL, USA) and oral hygiene instruction was given to each subject.

Post-surgical procedure

Participants were prescribed antibiotics – Amoxicillin 500 mg 3 times a day for 5 days and analgesics, ibuprofen 400 mg after the surgery if required, and 0.2% chlorhexidine mouthwash to be used twice daily, from the following day of surgery. After 1 week posttreatment, periodontal dressing (Coe-Pak, GC America Inc., Chicago, IL, USA) and sutures were removed and oral hygiene instructions were reinforced.

At 3, 6, and 9 months recall, GI, PI, PPD, RAL, and defect depth reduction were recorded, radiographic evaluation was done, and oral hygiene instructions were reinforced.

Statistical analysis

Statistical software was used to analyze the data (Statistical Package for Social Sciences [SPSS] for Windows, Version 22.0. Released 2013. Armonk, NY: IBM Corp.). To achieve 95% power and detect mean differences of the clinical parameters between groups, 18 sites per group were required.

Descriptive statistics

Descriptive analysis of all the explanatory and outcome parameters was done using frequency and proportions for categorical variables, whereas mean and Standard deviation was used for continuous variables.

Inferential statistics

One-way ANOVA test followed by Tukey's post hoc analysis was used to compare the mean values of study parameters between different study groups. Repeated measures of the ANOVA test followed by Bonferroni's post hoc analysis were used to compare the mean values of study parameters between different time intervals in each study group.

Student paired t-test was used to compare the mean defect depth reduction values between baseline and 9 months' time intervals in each study group. The level of significance (P value) was set at P < 0.05.

 Results



Seventeen participants with 57 intrabony defect sites in moderate and severe chronic periodontitis were selected and distributed to Groups I, II, and III. In the age and gender among the study groups, the age range was between 31 and 52 years with the mean age range of 39.89 ± 5.85 in Group I, 38.67 ± 6.76 in Group II, and 41.39 ± 6.63 in Group III with P = 0.95. There were 12 males and 6 females in Group I, 16 males and 5 females in Group II, and 11 males and 7 females in Group III. In all the three groups, there was a male predominance seen with 76.2% in comparison to females (P = 0.77). However, there was no statistical significant difference between the age and gender in all the three groups [Table 1].{Table 1}

A one-way ANOVA test was used to compare the mean values of different study variables between the three groups at baseline. The PI scores at baseline were P = 0.86, GI P = 0.36, PPD P = 0.28, RAL P = 0.92, and pocket depth reduction P = 0.23. There was no statistical significant difference of the different study variables between the three groups at baseline [Table 2]. One-way ANOVA test followed by Tukey's post hoc analysis was used to compare the mean values of different study variables between the different groups at 3, 6, and 9 months period. The test demonstrates that the mean PI, GI, PPD, and RAL scores of Groups I, II, and III at 3, 6, and 9 months showed statistically significant difference. However no statistical significant differences were seen in PPD between Group II (5.29 ± 1.7) and III (5.56 ± 134.) and between Group II (2.29 ± 1.01) and Group III (3.06 ± 1.11) at 3 months [Table 3],[Table 4],[Table 5]. The mean defect depth reduction scores between the three groups showed higher reduction in Group II (7.38 ± 1.46) in comparison to Group I (3.73 ± 0.33) and Group III (6.35 ± 0.92). There was a statistical significant difference at 9 months' period (P < 0.001) [Table 6]. Comparison of the mean percentage of defect depth reduction in Group I, II, and III shows that Group II (72.75%) has shown better results than Group I (41.59%,) and Group III (62.11%.) [Graph 1].{Table 2}{Table 3}{Table 4}{Table 5}{Table 6}[INLINE:2]

 Discussion



Periodontitis is a multifactorial disease, but a common hallmark is alveolar bone destruction. Periodontal regenerative procedures have evolved from debridement of vertical bony defects alone to the use of various materials in regeneration of the periodontal defects. The explosion of knowledge and understanding of the role of PC and their mechanisms of action and molecular signaling pathways have paved a way for many new therapeutic alternatives that can be recruited for in situ periodontal regeneration. This study was conducted to evaluate the efficacy of i-PRF (sticky bone) in comparison to PRF with OFD in chronic periodontitis, in the treatment of intrabony defects. The results of the present clinical study have demonstrated that using either i-PRF (sticky bone) or autologous PRF along with OFD in treating intraosseous defects in chronic periodontitis will improve the clinical and radiographic outcomes in comparison to OFD alone.

OFD or access flap surgery was one among the earliest procedures used and has been shown to result in successful treatment of intrabony defects. In clinical trials, evaluation of regenerative techniques has been conventionally done using OFD as the control procedure. The mean bone gain in our study was 3.73 ± 0.33 at the end of' 9 months which was comparatively higher than the mean bone fill of 1.1 mm in a study done by Karring et al.[15] In comparison to Sharma et al.[12] study, the amount of complete clinical closure was 1.80% in the OFD group, while in our study, it was 41.59% in the OFD. Even when used as the control procedure, OFD resulted in significant clinical benefits, with PPD reduction of 3.27 ± 0.97 and also gain in RAL of 3.28 ± 1.67 which is in accordance to the systematic review by Graziani et al.[16]

A liquid formulation of PC termed i-PRF without the use of anticoagulants was investigated by Miron et al.[17] Standard PRP and i-PRF (centrifuged at 700 rpm (60G) for 3 min) were compared for growth factor release up to 10 days (8 donor samples). i-PRF possesses the ability to induce higher fibroblast migration, release higher concentrations of various growth factors, and express platelet-derived growth factor (PDGF), transforming growth factor-β (TGF-β), and collagen 1. Future research is now necessary to further validate the use of i-PRF as a bioactive agent capable of stimulating tissue regeneration.

Choukroun and Ghanaati[18] analyzed systematically the influence of the relative centrifugation force on leukocytes, platelets, and growth factor release within fluid PRF matrices. Flow cytometry was applied to determine the platelets and leukocyte number. A quantification of 1 and 24 h after clotting using ELISA was done to determine the growth factor concentration. Low-speed centrifugation concept enriches growth factors, platelets, and leukocytes within fluid PRF-based matrices. In a study by Jasmine et al.[19] focused on an in vitro antibacterial and antibiofilm activity of i PRF against pathogenic oral Staphylococcus isolates. This could act as an antimicrobial peptide and potential bioactive agent to prevent postoperative infections at surgical sites.

i-PRF being a recent invention, most of the studies done are animal studies and clinical trials done in the field of oral surgery. However, to date, no study has been done with the use of sticky bone in intrabony defects. In our study, in the sticky bone group, the mean PI (1.65 ± 0.18) and GI (1.19 ± 0.06) showed subsequent improvement from baseline to 9 months. Similarly, there was a reduction in the PPD from baseline to 9 months (5.80 ± 1.54). The RAL scores (5.43 ± 1.47) and defect depth reduction (7.39 ± 1.46) from baseline to 9 months also showed improvement; however, a statistically significant difference was observed in all the parameters in the sticky bone group.

PRF has been utilized in various procedures such as management of intrabony defects, gingival recession, furcation defects, extraction socket preservation, and accelerated healing of wounds.

In comparison to a study done by Sharma and Pradeep,[12] they explored the effectiveness of autologous PRF in the treatment of intrabony defects; there was a mean defect fill of 48.6% in the PRF group. In our study, there was a significantly greater defect fill of 62.11% in comparison to the above study. A clinical study done by Pradeep et al.[20] explored the effectiveness of autologous PRF versus PRF + hydroxyapatite (HA) in treatment of inflammatory bowel disease (IBDs) in patients with chronic periodontitis. A significant greater percentage of mean bone fill was found in the PRF + HA (63.39% ± 16.52%) and PRF (56.46% ± 9.26%) groups compared to controls (15.96% ± 13.91%). In our study, the percentage of bone fill (62.11%.) was higher in comparison to the PRF group and was almost similar to the PRF + HA group. The variations in fibrin network patterns of the PRF in different age groups were determined. Mean radiographic IBD fill for Group I was 69.29%, for Group II was 74.44%, and for Group III was 75.01%. However, the percentage of bone fill at the end of 9 months was 62.11% in the PRF group, which was less in comparison to a study done by Yajamanya et al.[21] This study is first of its kind because of the comparison of PRF and i-PRF (sticky bone) in comparison to OFD was done in the intrabony defects. There was a statistically significant difference in all the three groups and their subgroups. However, Group II (i-PRF) showed much better results in terms of improvement in the clinical parameters and the defect depth reduction with marginal higher bone level. At the end of 9 months, the percentage of defect depth reduction for OFD was 41.59%, i-PRF was 72.75%, and PRF was 62.11%.

Thus, within the limitations of the present study, it can be demonstrated that, compared to OFD alone, the use of either sticky bone and PRF along with OFD in the treatment of intraosseous defects presents with better clinical and radiographic outcomes. Further, intergroup comparison of sticky bone and PRF showed no statistically significant differences. However, in terms of percentage of defect fill, Group II (sticky bone) shows better results than autologous PRF which could be attributed to the ability of i-PRF to release higher concentrations of various growth factors and induced higher fibroblast migration and expression of PDGF, TGF-β, and collagen 1, and its higher BMP and cytokine release; further, the use of bone graft has contributed to the improvement in the defect depth reduction from baseline to 9 months.

The limitations of this study include a small sample size and only two- and three-walled defects were considered. To overcome the shortcomings of this study, a greater number of multicenter trials, longitudinal, prospective studies should be carried out in different ethnic groups, with larger sample size to determine the efficacy of i-PRF (sticky bone) in intrabony defects with standard clinical parameters. Clinical trials can be performed using i PRF and PRF in horizontal bone defects, in degree II furcation defects, two and three walled and combined intrabony defects. It can also be used in diabetic, smokers, and with biomarkers such as BMP 2, osteoprotegerin.

 Conclusion



Thus, within the limitations of the present study, it can be concluded that, compared to OFD alone, the use of either i-PRF or autologous PRF along with OFD in the treatment of periodontal intraosseous defects presents with better clinical and radiographic outcomes.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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