ORIGINAL RESEARCH

https://doi.org/10.5005/jp-journals-10063-0152
CODS Journal of Dentistry
Volume 15 | Issue 2 | Year 2023

Evaluation of Mechanical, Chemical, and Structural Properties of Leukocyte Platelet-rich Fibrin, and Advanced Platelet-rich Fibrin: An In Vitro Study

Trijanya Gowda¹, Narayan N Valavalkar², Syeda M Fatima³

^1–3Department of Periodontics, College of Dental Sciences, Davangere, Karnataka, India

Corresponding Author: Narayan N Valavalkar, Department of Periodontics, College of Dental Sciences, Davangere, Karnataka, India, Phone: +91 8618725056, e-mail: editorcodsdvg@gmail.com

Received: 15 March 2024; Accepted: 10 April 2024; Published on: 17 May 2024

ABSTRACT

Aim: This study was an attempt to evaluate the mechanical and chemical degradation properties of the fibrin architecture and to compare leukocyte–platelet-rich fibrin (L-PRF) and advanced PRF (A-PRF) based on these properties.

Materials and methods: A total of 30 subjects, with 10 subjects for each test, were taken to evaluate the properties of the PRF membranes. The blood samples were immediately centrifuged using a tabletop centrifuge at 1,500 RPM for 14 minutes for A-PRF and 2,700 RPM for 12 minutes for L-PRF. A tensile test was performed using a universal testing machine. The in vitro degradation test of the prepared PRF clots was conducted by placing the PRF clots in 0.01% trypsin solution containing 2.5% glutaraldehyde in 0.1 M phosphate buffer solution for 24–48 hours. Scanning electron microscope (SEM) evaluation of the PRF clots was done under both low and high magnification.

Results: The results showed a statistically significant increase in the tensile strength, modulus of elasticity, and toughness of L-PRF when compared with A-PRF. The degree of degradation was statistically decreased in L-PRF when compared with A-PRF. On SEM analysis, L-PRF showed leukocytes and platelets were clumped with dense matrix formation with increased interfibrous space, while in A-PRF, leukocytes and platelets were well distributed along the entire surface of the membrane with decreased interfibrous space.

Conclusion: Results from the present study indicate that L-PRF through high-speed centrifugation has enhanced mechanical and structural properties, which yields a membrane with characteristics that are desirable for guided tissue regeneration (GTR) procedures.

How to cite this article: Gowda T, Valavalkar NN, Fatima SM. Evaluation of Mechanical, Chemical, and Structural Properties of Leukocyte Platelet-rich Fibrin, and Advanced Platelet-rich Fibrin: An In Vitro Study. CODS J Dent 2023;15(2):48–54.

Source of support: Nil

Conflict of interest: None

Keywords: Degradation, Modulus of elasticity, Platelet-rich fibrin, Scanning electron microscope

INTRODUCTION

Periodontal disease can be attributed to soft connective tissue breakdown, bone loss, and detachment or the connection of the connective tissues from the tooth’s cementum. The subjects were not having their dental issues treated. The process of new genesis and conversion of damaged or afflicted tissue to regain the obscured function and structures, keeping in view the plausible periodontal therapeutics, can be described as periodontal regeneration.¹^,²

Various techniques, such as guided bone regeneration (GBR) and guided tissue revival, employ barrier membranes to categorize the bone from the epithelium and connective tissue between periodontal ligaments to achieve optimal regeneration of the defect.

Guided tissue regeneration (GTR) membrane must have many different purposes with respect to physical, architectural, and biological adapting characteristics, having the potential to boost vascularized ingrowth and overall coordination without epithelial cell and connective tissue proliferation into the afflicted portion, further accelerating functional tissue regeneration of the cells that are relevant for creating the new periodontal tissue which is supposed to coincide with temporary degradation that allows space for regenerated periodontal tissue.³

Since the 1970s, the self-healing property of platelets has come to be known in scientific light. It is self-invigorating by property, with 90% composition in naturally occurring blood. The underlying concept of using platelets is associated with human blood protein production that could be managed as growth factorials and were capable of assisting angiogenesis and tissue proliferation with the objective that there would be improved blood circulation so as to achieve improved tissue regrowth.⁴

As the literature suggests, the benefits of platelet-rich plasma (PRP) as first-generation therapeutics are due to a high concentration of platelets but a minimal amount of fibrinogen. Nevertheless, the complexity of the blood PRP preparation process and possible cross-infection via the use of components for bovine thrombin provided the basis for the development of new platelet concentrates categories containing entirely autologous platelets called platelet-rich fibrin (PRF) or Choukroun’s PRF.⁵

The use of PRP, which was the first-generation platelet concentrate, showed appealing and successful outcomes. In 2001, Choukroun et al. concocted a fibrous matrix that is embroidered with cytokines growth factors and cells. These are the components that are released slowly with time and demonstrate selective permeability and hence get used as a resorbable barrier.⁶

The growth factors that result from platelets in the presence of fibrin matrix exhibited to proliferate the mitogenic feedback in the periosteum in order to help in a normal bone healing process.⁷

Besides that, fibrin also acts as a bridge molecule that promotes various cell interactions and offers cells all the provisional matrix where the cells can multiply, organize, and carry out their functions, particularly in areas that have infection or inflammation.⁸

Lately, the newest developments in the preparation techniques of PRF have generated advanced PRF (A-PRF). It employs the low-speed centrifugation concept (LSCC), which, consequently, results in the incremental outcome of the growth factors in comparison with those produced by traditional PRF. It is via A-PRF that leukocytes, platelets, circulating stem cells, and cells of endothelial origin gather and form a network around the fibrin clot. Through a cautious decrease in centrifugation speed, A-PRF decreases the infiltration of leucocytes into red blood cells. The LSCC has simplified the usage of PRF in periodontal reconstruction. Fewer centrifugation time may diminish cell decimation by centrifugation g-forces, which surges the whole remaining cell count inside the topmost layer of PRF, allowing an incremental number of leukocytes to lie in the fibrin meshwork. Third-generation platelet aggregate is A-PRF, which corresponds to wound ameliorative meshwork comprising circulating stem cells, leukocytes, platelets, and endothelial cells inside fibrin clots. Keeping this biological substance liberates growth factors that accelerate tissue regeneration and the healing of both the hard and soft tissue.¹⁰

Then, upon activation, platelets take their job of a binder together with fibrin, making the fibrin matrix stronger. This network is made up of both leukocytes and platelet growth factors, which are entrapped at the same time. Thus, it becomes necessary to study the architecture of fibrin. The slow-release profile of these growth factors gradually serves as the unusual biomarker that determines the regenerative potential of the biomaterial.¹¹

Measuring PRF resistance towards enzymatic degradation in periodontal tissues is crucial, especially if they are going to be employed as barriers in regenerative treatments. Despite the many studies that have been conducted to investigate platelet as well as growth factor concentrates, few have extended the analysis of the fibrin architecture mechanical and chemical degradation properties of platelet concentrates. Thus, this study is an attempt to evaluate the chemical-based and physical degeneracy characteristics of the fibrin architecture and to contrast leukocyte–PRF (L-PRF) and A-PRF established on these properties.

OBJECTIVES

To evaluate and analyze the physical properties, which encompass tensile strength, coefficient of elasticity, and firmness of A-PRF as well as L-PRF.
Correlative study of the chemical-based degenerative aspects of A-PRF and L-PRF.
To analyze the structural characteristics, such as the fibrin network and cell contents of L-PRF and A-PRF, using a scanning electron microscope (SEM).

MATERIALS AND METHODS

Patient samples in the present study were chosen from the outpatient Department of Periodontics, College of Dental Sciences, Davangere, Karnataka. The abouts of the study and its translational benefits were explained to the volunteers; thereafter, verbal and written informed consent was obtained to take part in the study before the outset.

Patients of age-group lying between 25 and 45 years with notified inclusion and exclusion criteria, incorporating both the gender-based samples.

Inclusion Criteria

Patient samples without any vascular morbidities were attributed as healthy, having platelet scores within a normal range (1.5–3 lakhs).

Exclusion Criteria

Patients with known systemic disease, which includes anemia, blood disorders, patients who consume tobacco, patients on anticoagulant therapy, patients on immunosuppressive therapy, and pregnant and lactating mothers.

Platelet-rich Fibrin Clot Preparation

From selected patient samples, venous blood was gathered inside the elbow in the antecubital vein in a 10 mL sterile glass vacuum tube. After collecting the samples, they were quickly centrifuged to collect plasma. Blood samples were centrifuged in a Remi 4C centrifuge at 2,700 RPM for about 12 minutes. In order to isolate the L-PRF (12-minute centrifugation), A-PRF was isolated by centrifuging for 14 minutes. Corresponding to centrifugation, the clot was separated carefully, and three different layers were suspended within the tube.

Preparing the Membrane

Using sterile tweezers, the prepared PRF clot having platelets composed in the middle layer of the tube, the bottommost layer having red blood cells, while the acellular plasma as the topmost layer in the tube was separated from the tube. Using scissors, the clot was separated from the red blood cells (RBC) base, and the adhering red blood cells where scissors were used to separate the clot from the RBC base, and the attached red blood cells were piqued and removed. The primary PRF clots are placed into a compression box with PRFs and further covered with the compressor. Corresponding to a time span of 10 minutes, the PRF membrane can be utilized for further studies.

Preparation of a Plexiglass Mold

A custom plexiglass mold was designed to maintain the uniformity of size and volume of the fibrin specimen. The mold thickness was equal to 2 mm, and the width was gradually reduced from 2 mm and further narrowed mid to 6 mm till greater ends. The mold was estimated as 31 mm, and the total volume was 104 mm³. The neck had a smaller diameter, making it the weakest area where the specimen would eventually crack.

Tensile Test

In order to test the tensile strength of the globally accredited testing machine Tinius Olsen h50KS, India, comprising a maximal load cell of 500 N while functioning in a classically established ambient environment. The greater ends of the dog-bone shaped samples are attached using clips of the machine, preventing any tensile forces so that the primary apparent gauge dimension specified to 10 mm is fixed for the whole specimen set. The payload by tensile machine was exercised to the membrane along its vertical axis at a cross main speed of 2 mm/minute. The traction force was applied until the total rupture of the membrane. The greatest load at specimen failure was noted. Estimation of the tensile strength was made employing the formula:

Where S is strength due to tensile payloads, F is the greatest force in Newton (N), and A is reckoned as unit area (m²).

Young’s modulus of elasticity (stiffness) of the samples was determined by dividing stress by strain altogether, with the total area within the curve attributed to the firmness of the samples.

In Vitro Degradation

A 0.01% concentration of trypsin was used to degrade the PRF membranes incubated at 37.0°C to observe the alterations in the perversions of A-PRF and L-PRF. Afterward, samples were taken and weighed using an electronic micro-weighing scale before the start of the experiment. After the trypsin treatment, the trypsin solution was reintroduced every 24 hours. The noteworthy differences in weight before and after the trypsin treatment, that is, the enzymatic degradation, were marked. The degradation degree (%) of PRF was studied by correlating the percentage distinctions PRF sample weight after submersing in 0.01% trypsin and recorded after an interval of a day, with the formula:

Scanning Electron Microscope Examination

A cryo-SEM was used to examine the surface microstructure of the membrane. The PRF clots were immersed in 2.5% neutralized glutaraldehyde to fix them. Afterward, samples were dehydrated by employing cycles of ethanol solutions of varying concentrations and n-butanol. The next step included freeze-drying and further examination in a cryo-scanning microscope with an incremental voltage of 20 KV. The dried samples were sputter-coated with gold and observed in a cryo-SEM.

Statistical Analysis

The calculated datasets are depicted as mean ± standard deviation. Unpaired Student’s t-test was used to calculate mean differences among the experimental and control groups.

RESULTS

Mechanical test

A total of 20 samples were obtained for the assessment of the physical properties of the PRF membranes. Further, their mean value was calculated and compared. Upon assessing the PRF membranes, it appeared that L-PRF had ultimate tensile strength (0.14 ± 0.16 N/mm) as shown in Table 1 and Figure 1, modulus of elasticity (0.054 ± 0.003 MPa) as shown in Table 2 and Figure 2 and toughness (0.39 ± 0.067 J/m) compared to A-PRF as shown in Table 3 and Figure 3. It was observed that A-PRF had the least tensile strength (0.12 ± 0.22 N/mm²), modulus of elasticity (0.048 ± 0.11 MPa), and toughness (0.31 ± 0.063 J/m³).

**Table 1:** Tensile strength of the PRF membranes
Group	N	Means	Statistic (p-value)
L-PRF	10	0.14 ± 0.16
A-PRF	10	0.12 ± 0.22	p = 0.017 (statistically significant)

**Table 2:** Modulus of elasticity of the PRF membranes
Group	N	Means	Statistic (p-value)
L-PRF	10	0.054 ± 0.003
A-PRF	10	0.048 ± 0.11	p = 0.015 (statistically significant)

**Table 3:** Mean toughness between PRF membranes
Group	N	Means	Statistic (p-value)
L-PRF	10	0.39 ± 0.067
A-PRF	10	0.31 ± 0.063	p = 0.014 (statistically significant)

Fig. 1: Comparison of tensile strength between L-PRF and A-PRF

Fig. 2: Comparison of modulus of elasticity between L-PRF and A-PRF

Fig. 3: Comparison of toughness between L-PRF and A-PRF

Chemical Degradation

The maximum degradation when the PRF membranes were compared was found in A-PRF (51.18 ± 4.81), and the least was found in L-PRF (31.69 ± 3.21), as shown in Table 4 and Figure 4. The percentage difference in degradation of the PRF membrane was found to be significant when applied with statistical correlations.

**Table 4:** Mean degree of degradation between L-PRF and A-PRF
Group	N	Means	Statistic (p-value)
L-PRF	10	31.69 ± 3.21
A-PRF	10	51.18 ± 4.81	p ≤ 0.001 (Statistically significant)

Fig. 4: Comparison of degree of degradation between L-PRF and A-PRF

Scanning Electron Microscopic Findings

In the first and foremost step, the PRF samples were subjected to freeze drying and encapsulated with gold using a sputter-coating procedure. Afterward, the samples were examined using microscopic scanning electrons. Upon SEM investigation of L-PRF, the leukocytes and platelets mostly accumulate around its distal region, with a gradual decrease in platelet density in the proximal portion. The L-PRF matrix had thick-arranged fibrin fibers that were strongly polymerized with the fibrin matrix and had a dense structure with minimal interfibrous space. Under SEM investigation of A-PRF, platelets and leukocytes were regularly assigned with an acclivity in the wholesome density of platelets at the proximal portion. The matrix had a porous structure with large interfibrous space, and thin fibrin fibers were mildly polymerized with the fibrin matrix. The SEM analysis demonstrated L-PRF with dense fibers and few interfibrous spaces when compared with A-PRF (Fig. 5).

Figs 5A to D: Scanning electron microscope analysis: (A and B) L-PRF 1.5×; (C and D) A-PRF 1.5×

DISCUSSION

Collagen-derived materials have proved effective in GTR procedures due to their biocompatibility properties, which are better than those of other approaches. Yet, product variability and the inability to determine the rate of resorption, which is vital for the success of GTR, are the reasons for concern. Likewise, the utilization of membranes constructed from animal tissues is linked with elevated hazards of disease communication and has raised arguments for cultural and ethical considerations. Studies revealed that fibrin-based membranes may be superior scaffolds to promote the development of osseous cells and periosteal tissues comparable to collagen membranes in vitro conditions.⁹

Platelet concentrates have advanced in regenerative therapy. Platelet concentrates are designed to accelerate, promote, and boost the healing process, and nowadays, they are used in various procedures involving periodontal tissues to enhance the regeneration of tissues. The principle of platelet concentrates is to gather the fibrin adhesive characteristics having growth factors in platelets, thereby creating a good foundation for wound revival and tissue reformation.¹¹

Out of all platelet concentrates, PRF is labeled as a completely autologous blood concentrate system that is based on the patient’s own blood, eliminating the need for any external anticoagulants. This system provides a simple preparation process that can be fitted into the clinical routine. The preparation procedure involves exposure to a centrifugation protocol, which involves contact activation and can facilitate the internal coagulation cycle beyond any biochemical conversion. This proposition enhances the consistent and timely polymerization of blood clots, which provides a blood clot with finer and softer fibrin junctions. This not only provides greater elasticity but also strengthens the meshwork of inherent cytokines and growth factors. PRF serves a very significant role in cell proliferation, migration, and chemotaxis, so it can work as a good healing matrix.¹²

During surgical procedures, PRF is used as a resorbable membrane to accelerate GBR. It is a methodology that does not allow the circulation of undesirable cells across the defective side of the bone and enhances the comfortable space for osteogenic and angiogenic cells to migrate and grow. Furthermore, it is possible to organize the conductive fibers in a setup that lets the blood clot under it become mineralized.¹³

Platelet-rich fibrin’s key points revolve around three elements that fulfill regeneration needs. They serve as host cells as well as consist of a fibrin matrix having a three-dimensional structure and growth factors varying in kind, among which there are translating growth factor-β, platelet-derived growth factor, vascular endothelial growth factor, insulin-like growth factor, and epidermal growth factor. Recent findings have, in particular, demonstrated that white blood cells play a crucial role in the wound tissue healing process, having the potential to promote new blood vessel growth and tissue reformation.¹²

Platelet-rich fibrin meets all three crucial criteria for tissue regeneration: it comprises a scaffold with the intrinsic three-dimensional fibrin structure, contains autologous cells that play a pivotal part in amelioration, and is also a reservoir for growth factors that accompany the healing process and are gradually released over a 10–14-day period.¹²

Recent accomplishments in PRF preparation have made a breakthrough of advanced PRF possible with the addition of the LSCC. This technique relies on lesser centrifugal forces to ensure that more leukocytes get retained within the fibrin matrix. The low centrifugation duration reduces cell sedimentation because of stronger g-forces, which in turn leads to more cells staying within the upper layer of PRF. The dense presence of leukocytes within the fibrin matrix enhances the production of factorials, causing overall growth. The usage of LSCC indicates that matrix regeneration potential can be improved by minimizing the relative centrifugal force (RCF). With this variegated conglomeration of these processes, a more porous scaffold is developed, which behaves as a cistern of growth factors and thus enhances the process of regeneration.¹⁴

The objective of this study is to accomplish a microscopic examination of scanning electron microscopy (SEM). The samples for this study were from a population of 25–45 years old and will also specifically avoid gender, race, weight, and malfunction in order to avoid potential biased altering from these groups. In acute traumatic injuries, despite the presence of studies on platelet concentration levels, the biomechanical properties of these materials are the least investigated in comparison to the concentration of platelets and growth factors. Nevertheless, the quality of the mechanical characteristics of the membrane also plays a role in the success rate of GTR procedures.

Mechanical testing can be conducted by applying several tests like the use of the universal testing machine (Tinius Olsen h50KS, India) (Rahman) or performing a surface indentation test with T1 950 Tribo indenter (Sam et al.).¹^,¹² The study was planned to determine and correlate the physical properties between two platelet concentrates. A PRF compression box is implemented in order to make sure the standard size and thickness obtained from the clot are uniform in the PRF membrane. These membranes were then formed in bone-shaped plexiglass molds that allowed for a replication of the size, shape, and volume required.

The findings revealed that L-PRF showed significantly higher tensile strength, highest tensile strain, coefficient of elasticity, and overall firmness compared to A-PRF. These differences in mechanical properties may stem from structural disparities attributed to variations in polymerization processes. Furthermore, the elevated modulus of elasticity noticed in L-PRF in relation to A-PRF indicates that reducing gravitational force during centrifugation can lead to the generation of a more elaborate fibrin meshwork, leading to reduced firmness of autologous platelet-fibrin preparations.¹⁵

This outcome is consistent with the research conducted by Khorshidi et al. in 2016, which correlated L-PRF membranes with PRGF/Endoret membranes. Their study concluded that L-PRF membranes exhibited superior mechanical strength and were more clinically manageable than membranes produced by the PRGF-Endoret system.¹⁶

Maintaining the architectural probity of the implanted bioabsorbable impediments inside the membrane is vital for achieving the desired outcomes as a GTR membrane. Various techniques can be employed to assess the structural integrity of fibrin membranes, including the orbital shaker test (Sam et al.) and numerous enzymes like plasmin (Rahman et al.) and trypsin (Rusyanti et al.).¹^,¹²^,¹⁷

The purpose of the study was to assess the chemical degradation properties of two types of platelet concentrates by comparing them. In vivo, fibrin is mainly degraded by plasmin, which is a long process. On the other hand, the evaluation of fibrin degradation using plasmin in vitro is time-consuming. Besides, fibrin may also be processed by other proteases outside of cell culture. Thus, in this study, the commonly used trypsin plus EDTA was employed. Additionally, trypsin–EDTA 0.25% was used in the degradation test, which was acting by the breakage of chemical bonds of peptidyl nature over the carboxylic side of amino acid side chains in the fibrin matrix. The research focused on the in vitro degradation of 0.01% trypsin enzymes targeting PRF membranes, which served as a reflection on the proteolytic resistance of PRF in periodontal tissues. This is vital because the PRF membranes are used as barrier membranes in regenerative treatment, adhering to GTR and also with GBR.

The degradation process was started by immersing both the sets of A-PRF and L-PRF membranes in a liquid solution containing 0.01% trypsin. The degree of degradation (%) of PRF was assessed by comparing the weight percentage difference of the PRF samples before and after immersion in the trypsin solution, with observations made at 24-hour intervals. The samples underwent degradation induced by trypsin, which was evident through a decrease in the weight of the PRF membranes after treatment, with some samples experiencing complete degradation within 48 hours. The results of the chemical degradation test indicated that the mean degree of degradation observed in L-PRF samples was 31.69 ± 3.21%, whereas in A-PRF samples, it was 51.18 ± 4.81%.

A correlation between mechanical properties and chemical degradation rate was observed, with L-PRF exhibiting the superlative physical property amounts with diminished deterioration, whereas A-PRF demonstrated the greatest perversion rates and the minimum mechanical characteristics in calculatable decrees. These findings were statistically important, demonstrating a clear trend favoring L-PRF over A-PRF in terms of both mechanical strength and resistance to degradation.

These study findings align with the former investigation conducted by Sam et al. in 2015, which compared the in vitro degradation rate of PRF with two commercially available collagen membranes, directing to assess its overall degradation profile. The study revealed that the degree of degradation of the L-PRF membrane was almost 31% of its initial weight. Moreover, the results indicated that the PRF membrane presented correlative results to other membranes in measures of setting its physical characteristics with time.¹

Scanning electron microscopic analysis was used to examine the ultrastructure of L-PRF and A-PRF membranes, aiming to gain an understanding of their biological properties. Both membranes exhibit a composition of fibrillar and cellular components, primarily containing human platelet cells. This unique architecture potentially presents a meshwork with an interarray of cells necessary for periodontal regeneration. When examined in the SEM, it was noted that inside L-PRF membranes, the platelets and white blood cells were clustered together, forming a dense matrix. In contrast, A-PRF membranes displayed a more uniform distribution of leukocytes and platelets across the entire membrane surface without noticeable clustering. Furthermore, A-PRF exhibited a major porous architecture with wider interfibrous spacing when correlated with L-PRF membranes.

The data found by Sam et al. in 2015 compared L-PRF with commercially available membranes. The results in L-PRF membranes indicated resemblances at a structural level. Spherical structures were revealed at the border of red and yellow part of the fibrin clot. These spheres were most likely immune cells. However, apart from this, plates were seen as a compact layer above the base fibrin on the border of the sediment area.¹

These findings align with those reported by Simões-Pedro et al. in 2022 in their in vitro comparative structural analysis of three distinct PRF membranes labeled as L-PRF, A-PRF, and A-PRF+. One eminent study showed that the PRF-L matrix was characterized by a compact structure in a refined network with thick fibers in an interfibrous area and the destruction of erythrocytes and leukocytes. Unlike the A-PRF method, which produced an intricate matrix containing interconnected and relatively thin fibers, the P-PRF method resulted in a dense network with fibers interconnected in an intricate manner.¹⁸

The importance of in vitro studies on various properties of altered types of PRF lies in their clinical implications for treatments such as addressing periodontal infrabony defects, wound healing promotion, extraction sockets management, etc.

Based on the article of Dragonas et al. in the 2018 review literature, the L-PRF can be used for the preservation of ridge, ridge augmentation, and maxillary sinus augmentation. L-PRF was exemplary in extraction sockets, but its effect on maxillary sinus lifting could not be generalized, and available data about ridge augmentation were scanty.¹⁹

Miron et al., in 2021, systematically review and meta-analysis highlights that PRF has positive results in terms of clinical conclusions with intrabony periodontal defects, like open flap debridement with bone grafting. It indicates the parity of both approaches. According to them, PRF combined with biomolecules can create a unique setting that could contribute to increased healing, which requires more research for clinical application.²⁰

The current study compares the mechanical and chemical properties and fibrin structure of two dissimilar PRF membranes. The above findings patronage the eminence of L-PRF in dimensions of material characteristics and degradability of the PRF membrane, which may be advantageous for the treatment of periodontal disease. Further clinical studies are required to examine the paraphernalia of cell types over a wide spectrum of platelet concentrates.

CONCLUSION

The limitation of the present study lies in the fact that L-PRF material made by high-speed centrifugation would display better mechanical features and can be used as a tissue regeneration (GTR) membrane. Moreover, the current research provides a strong basis for future studies probing growth factor release and its possible cytotoxic effects; these discoveries will give rise to clinical applications of L-PRF in the regeneration of periodontium.

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