Platelet rich fibrin as a bioactive matrix with proosteogenic and proangiogenic properties on human healthy primary cells in vitro

Blood concentrates like platelet rich fibrin (PRF) have been established as a potential autologous source of cells and growth factors with regenerative properties in the field of dentistry and regenerative medicine. To further analyze the effect of PRF on bone tissue regeneration, this study investigated the influence of liquid PRF matrices on human healthy primary osteoblasts (pOB) and co-cultures composed of pOB and human dermal vascular endothelial cells (HDMEC) as in vitro model for bone tissue regeneration. Special attention was paid to the PRF mediated influence on osteoblastic differentiation and angiogenesis. Based on the low-speed centrifugation concept, cells were treated indirectly with PRF prepared with a low (44 g) and high relative centrifugal force (710 g) before the PRF mediated effect on osteoblast proliferation and differentiation was assessed via gene and protein expression analyses and immunofluorescence. The results revealed a PRF-mediated positive effect on osteogenic proliferation and differentiation accompanied by increased concentration of osteogenic growth factors and upregulated expression of osteogenic differentiation factors. Furthermore, it could be shown that PRF treatment resulted in an increased formation of angiogenic structures in a bone tissue mimic co-culture of endothelial cells and osteoblasts induced by the PRF mediated increased release of proangiogenic growth factors. The effects on osteogenic proliferation, differentiation and vascularization were more evident when low RCF PRF was applied to the cells. In conclusion, PRF possess proosteogenic, potentially osteoconductive as well as proangiogenic properties, making it a beneficial tool for bone tissue regeneration.

Biological Functions of Macromolecular Protein Hydrogels in Constructing Osteogenic Microenvironment

Irreversible bone defects resulting from trauma, infection, and degenerative illnesses have emerged as a significant health concern. Structurally and functionally controllable hydrogels made by bone tissue engineering (BTE) have become promising biomaterials. Natural proteins are able to establish connections with autologous proteins through unique biologically active regions. Hydrogels based on proteins can simulate the bone microenvironment and regulate the biological behavior of stem cells in the tissue niche, making them candidates for research related to bone regeneration. This article reviews the biological functions of various natural macromolecular proteins (such as collagen, gelatin, fibrin, and silk fibroin) and highlights their special advantages as hydrogels. Then the latest research trends on cross-linking modified macromolecular protein hydrogels with improved mechanical properties and composite hydrogels loaded with exogenous micromolecular proteins have been discussed. Finally, the applications of protein hydrogels, such as 3D printed hydrogels, microspheres, and injectable hydrogels, were introduced, aiming to provide a reference for the repair of clinical bone defects.

Effectiveness of Autologous Platelet Concentrates in the Sinus Lift Surgery: Findings from Systematic Reviews and Meta-Analyses

Maxillary sinus augmentation is one of the most predictable procedures for the rehabilitation of the posterior maxilla. The current overview aimed to summarize the findings provided by systematic reviews (SRs) and meta-analyses on the effectiveness of autologous platelet concentrates (APCs) in sinus lift and to assess the methodological quality of the included SRs. Three electronic databases have been explored. SRs and meta-analyses addressing the effectiveness of APCs in sinus lift technique were included. Clinical, radiographic and histomorphometric findings were considered for APCs as solely grafting materials and APCs in combination with biomaterials. Outcomes were implant survival rate (ISR), implant stability (IS), implant failure (IF), postoperative complications, histomorphometric findings, radiographic bone gain, bone volume and bone density. The methodological quality of the included SRs was assessed using the updated version of "A Measurement Tool to Assess Systematic Review" (AMSTAR-2). Thirty SRs were included. The methodological quality of the included reviews ranged from critically low (3 studies) to high (9 studies). The included SRs showed favorable clinical outcomes, short-term new bone formation and no biological complications when APCs were used both as solely graft material or in combination with other biomaterials. However, no significant additional effects in the long-term period were observed. APCs did not add any further positive effects compared to the physiological healing derived by the natural blood clot. The current overview of SRs highlighted the need for high-quality SRs evaluating the role of APCs in sinus lift though network meta-analyses, in order to identify the most powerful material for sinus lift augmentation. The use of APCs improves the healing of soft tissues and the postoperative quality of life in the short-term period. Thus, its application can be recommended.

Immunomodulation of Cancer Cells Using Autologous Blood Concentrates as a Patient-Specific Cell Culture System: A Comparative Study on Osteosarcoma and Fibrosarcoma Cell Lines

The understanding that tumor cells might evade immunity through various mutations and the potential of an augmented immune system to eliminate abnormal cells led to the idea of utilizing platelet-rich fibrin (PRF), a blood concentrate containing the body's immune elements as an adjunctive therapy for localized tumors. This study is the first that evaluated the effect of PRF generated with different relative centrifugal forces (RCFs) on osteoblastic and fibroblastic tumor cell lines MG63 and HT1080 with regard to cell viability, cytokine and growth factor release, and the gene expression of factors related to the cell cycle and apoptosis. Our findings could demonstrate decreased cell proliferation of MG63 and HT1080 when treated indirectly with PRF compared to cell cultures without PRF. This effect was more distinct when the cells were treated with low-RCF PRF, where higher concentrations of growth factors and cytokines with reduced RCFs can be found. Similar patterns were observed when assessing the regulation of gene expression related to the cell cycle and apoptosis in both MG63 and HT1080 cells treated with PRF. Despite variations, there was a consistent trend of an up-regulation of tumor-suppressive genes and a down-regulation of anti-apoptotic genes in both cell types following treatment with high- and, particularly, low-RCF PRF formulations.

Does Liquid/Injectable Platelet-Rich Fibrin Help in the Arthrocentesis Treatment of Temporomandibular Joint Disorder Compared to Other Infusion Options? A Systematic Review of Randomized Clinical Trials

Temporomandibular joint disorders (TMDs) are prevalent musculoskeletal conditions involving pain and dysfunction of jaw mobility and function, which have proven difficult to treat satisfactorily. The present study aimed to assess the effectiveness of a liquid platelet-rich fibrin (i-PRF) infusion during arthrocentesis versus other options using coadjuvant materials to reduce TMD symptoms. A literature search was conducted using PubMed, EMBASE, Web of Science, Scopus, and ClinicalTrials.gov for RCTs published before January 2024, comparing i-PRF to any other TMD treatment. This systematic review was registered on PROSPERO (CRD42023495364). The searches generated several recent RCTs that compared i-PRF injection combined with arthrocentesis (AC) to AC-only or AC with platelet-rich plasma (PRP). The outcomes analyzed included measures of pain (visual analog scale, VAS), maximum mouth opening, joint sounds, and MRI-verified changes in joint structure. Across the RCTs, the addition of i-PRF injection to AC resulted in significant improvements in pain relief, joint function, mouth opening, and structural changes compared to AC-only or with PRP over follow-up periods ranging from 6 to 12 months. Current clinical evidence favors using i-PRF as an adjunct to AC rather than AC-only or AC with PRP for the treatment of TMDs. The improvements in subjective and objective outcome measures are clinically meaningful. Still, additional high-quality RCTs with larger sample sizes and longer follow-ups are required to strengthen the evidence base and better define the role of i-PRF in TMD management guidelines.

Platelet-rich fibrin for rehydration and pre-vascularization of an acellular, collagen membrane of porcine origin

OBJECTIVES

Pre-vascularization of the collagen membranes with autologous platelet concentrates is a standard procedure in oral and maxillofacial surgery. This study analyzed the possible interaction of an acellular collagen membrane of porcine origin (NM) with platelet-rich fibrin (PRF) regarding its rehydration protocol with differences in pH values and effect on angiogenesis.

MATERIALS AND METHODS

NM was analyzed alone and combined with solid PRF by plotting or co-culturing with injectable PRF. Different media (venous blood, buffer solution with a fixed pH value of 7, saline solution, and injectable PRF) were used to analyze the influence on pH value during rehydration. Chorion allantois membrane assay (CAM) was applied to check pro-angiogenic effects after 24, 48, and 72 h, followed by immunohistochemical analysis.

RESULTS

Rehydration in injectable PRF showed acidity over time (p < 0.05). A definite pro-angiogenic effect of NM alone was found regarding neo-vessel formation supported by the respective light microscopically analysis without significant differences to PRF alone (p > 0.005). This pro-angiogenic effect could not be exaggerated when NM was combined with liquid/solid PRF (each p > 0.005).

CONCLUSIONS

Rehydration with liquid PRF of the collagen membrane results in acidity compared to a saline solution or patient's blood. The significant pro-angiogenic potential of the membrane alone resulted in enhanced neo-vessel formation that could not be optimized with the addition of PRF.

CLINICAL RELEVANCE STATEMENT

Using injectable PRF for rehydration protocol of the collagen membrane leads to acidosis that can ultimately optimize wound healing. Differences in the physio-mechanical interplay of collagen matrices and autologous platelet concentrates must result in clinical algorithms if pre-vascularization can maximize outcomes.

Injectable platelet-rich fibrin for treatment of female pattern hair loss

This case series evaluated use of injectable platelet rich fibrin (termed i-PRF+) for the treatment of female pattern hair loss (FPHL). Eleven individuals underwent 3-monthly intradermal injections of i-PRF+ using a mesotherapy gun. The mean number of hair follicles containing hairs per unit area improved at 3- and 6-months follow-up (p < .001), and all participants had a negative hair pull test. Hair volume and thickness, and patient-reported outcome scores also improved at follow-up (p < .001). Adverse effects were minor and self-limited. A series of three i-PRF+ injection sessions were effective for the treatment of FPHL, as shown by improved hair analysis parameters and patient self-assessment scores.

Platelet-Rich Plasma in Dermatology: New Insights on the Cellular Mechanism of Skin Repair and Regeneration

The skin's recognised functions may undergo physiological alterations due to ageing, manifesting as varying degrees of facial wrinkles, diminished tautness, density, and volume. Additionally, these functions can be disrupted (patho)physiologically through various physical and chemical injuries, including surgical trauma, accidents, or chronic conditions like ulcers associated with diabetes mellitus, venous insufficiency, or obesity. Advancements in therapeutic interventions that boost the skin's innate regenerative abilities could significantly enhance patient care protocols. The application of Platelet-Rich Plasma (PRP) is widely recognized for its aesthetic and functional benefits to the skin. Yet, the endorsement of PRP's advantages often borders on the dogmatic, with its efficacy commonly ascribed solely to the activation of fibroblasts by the factors contained within platelet granules. PRP therapy is a cornerstone of regenerative medicine which involves the autologous delivery of conditioned plasma enriched by platelets. This is achieved by centrifugation, removing erythrocytes while retaining platelets and their granules. Despite its widespread use, the precise sequences of cellular activation, the specific cellular players, and the molecular machinery that drive PRP-facilitated healing are still enigmatic. There is still a paucity of definitive and robust studies elucidating these mechanisms. In recent years, telocytes (TCs)-a unique dermal cell population-have shown promising potential for tissue regeneration in various organs, including the dermis. TCs' participation in neo-angiogenesis, akin to that attributed to PRP, and their role in tissue remodelling and repair processes within the interstitia of several organs (including the dermis), offer intriguing insights. Their potential to contribute to, or possibly orchestrate, the skin regeneration process following PRP treatment has elicited considerable interest. Therefore, pursuing a comprehensive understanding of the cellular and molecular mechanisms at work, particularly those involving TCs, their temporal involvement in structural recovery following injury, and the interconnected biological events in skin wound healing and regeneration represents a compelling field of study.

Radiological Evaluation and Biomechanical Stability of Implants Simultaneously Placed at the Sites with Sole Advanced Platelet-Rich Fibrin (A-PRF) Grafted Sinus Floor

Introduction

In this retrospective study stabilities of 24 implants simultaneously placed at posterior maxillae with sinuses grafted by advanced platelet rich fibrin (A-PRF) and newly formed bone around them were evaluated.

Patient and Methods

Fourteen augmented maxillary sinuses of 11 patients with a mean residual alveolar bone height of 4.55 mm were involved in this study. Maxillary sinus lifting via lateral window approach and implant site osteotomy were performed, and prepared A-PRF clots were used as sole graft material. Each of the implants was immediately placed with a good primary stability. Postoperative sixth month tomography images were compared with preoperative ones in order to calculate the gained bone height and implant stability quotient (ISQ) values were recorded.

Results

The new vertical mean bone height of 24 implant sites was 12.21 mm with an implant survival rate of 100%. ISQ values of the implants were ranging from 62 to 75 with a mean value of 68. Statistically the diameter of implant did not have any effect on new bone formation and the ISQ values, however the length of them did.

Conclusion

A-PRF as a graft material for sinus lifting with simultaneous implant placement is a reliable technique with its low cost and lack of immunogenic reaction risk.

Use of Leukocyte- and Platelet-Rich Fibrin to Prevent Osteonecrosis of the Jaws Associated with the Use of Bisphosphonate Therapy: A Case Series

Medication-related osteonecrosis of the jaws (MRONJ) consists of an area of exposed intraoral or extraoral bone that affects patients with a history of use of antiresorptive and antiangiogenic medications, and who have not undergone head and neck radiotherapy. Leukocyte- and platelet-rich fibrin (L-PRF) is an autologous material of great potential, used as an adjuvant in surgical treatments, especially where healing is compromised. The aim of this article is to report three cases of the use of L-PRF in the prevention of MRONJ in three female Caucasian under bisphosphonates therapy. Patient 1, 86 years old, with osteoporosis, complained of intense pain in tooth 33, which presented edema and periapical lesion and association with MRONJ. Patient 2, 61 years old, undergoing treatment for bone metastases due to breast cancer, reported pain symptoms in tooth 47, as well as suppuration in the dental element, grade I mobility, pain on periapical palpation and radiographically an endoperiodontal lesion was evidenced. Patient 3, 56 years old, also undergoing treatment for breast cancer, presented with severe pain in tooth 36. On clinical examination, she presented pain, mobility and suppuration, and radiographs indicated a furcation lesion on tooth 36. The treatment option in the three cases was the extraction of the affected teeth and the use of L-PRF to promote healing. All patients present a favorable outcome in follow-up. The use of L-PRF can be an adjuvant in the prevention of MRONJ; however, further studies are needed to prove its effectiveness.

Platelet-Rich Fibrin-Conditioned Medium as an Alternative to Fetal Bovine Serum Promotes Osteogenesis of Human Dental Pulp Stem Cells

Human dental pulp stem cells (DPSCs) exhibit multilineage differentiation capabilities and superior clonogenic and proliferative properties. However, the use of animal-derived components such as FBS raises concerns regarding the clinical application of stem-cell-based therapies. Platelet-rich fibrin (PRF) derived from human blood is rich in fibrin, platelets, and growth factors and acts as a bioactive scaffold for grafting with biomaterials. In this study, we assessed the efficacy of PRF-conditioned medium (CM) in promoting DPSCs proliferation and osteogenic differentiation compared with the standard culture medium supplemented with FBS. A comparison of DPSCs cultured in FBS and PRF-CM revealed no differences in characteristics or morphology. However, cells cultured with PRF-CM exhibited inferior proliferation rates and cell numbers during passage in comparison with those cultured with FBS. In contrast, DPSCs cultured in PRF-CM showed significantly higher levels of calcification, and RT-PCR confirmed that the gene expression levels of markers associated with osteoblast differentiation were significantly increased. The PRF-CM approach offers a convenient, straightforward, and advantageous method for culturing DPSCs, without relying on animal-derived components. In summary, this study introduces a novel application of PRF-CM for enhancing the osteogenesis of DPSCs, which provides an alternative to FBS culture medium and addresses concerns associated with the use of animal-derived components in clinical settings.

The Effects of Platelet-Rich Fibrin in the Behavior of Mineralizing Cells Related to Bone Tissue Regeneration-A Scoping Review of In Vitro Evidence

Platelet-rich fibrin (PRF) is a second-generation blood concentrate that serves as an autologous approach for both soft and hard tissue regeneration. It provides a scaffold for cell interaction and promotes the local release of growth factors. PRF has been investigated as an alternative to bone tissue therapy, with the potential to expedite wound healing and bone regeneration, though the mechanisms involved are not yet fully understood. This review aims to explore the in vitro evidence of PRF's effects on the behavior of mineralizing cells related to bone tissue regeneration. A systematic electronic search was conducted up to August 2023, utilizing three databases: PubMed, Web of Science, and Scopus. A total of 76 studies were selected, which presented in vitro evidence of PRF's usefulness, either alone or in conjunction with other biomaterials, for bone tissue treatment. PRF membranes' influence on the proliferation, differentiation, and mineralization of bone cells is linked to the constant release of growth factors, resulting in changes in crucial markers of bone cell metabolism and behavior. This further reinforces their therapeutic potential in wound healing and bone regeneration. While there are some notable differences among the studies, the overall results suggest a positive effect of PRF on cell proliferation, differentiation, mineralization, and a reduction in inflammation. This points to its therapeutic potential in the field of regenerative medicine. Collectively, these findings may help enhance our understanding of how PRF impacts basic physiological processes in bone and mineralized tissue.

Simultaneous or staged lateral ridge augmentation: A clinical guideline on the decision-making process

Lateral ridge augmentation is a standard surgical procedure that can be performed prior to (staged) or simultaneously with implant placement. The decision between a simultaneous or staged approach involves considering multiple variables. This paper proposed a decision-making process that serves as a guideline for choosing the best treatment choice based on the available evidence and the author's clinical experience.

Reduction of Inflammatory RANTES/CCL5 Serum Levels by Surgery in Patients with Bone Marrow Defects of the Jawbone

Purpose

The presence of bone marrow defects of the jawbone (BMDJ) is associated with increased levels of inflammatory cytokines such as RANTES/CCL5. The purpose of this study was to analyze if BMDJ therapy under real-world conditions reduces RANTES/CCL5 serum levels in BMDJ patients.

Patients and Methods

During this retrospective study, 113 BMDJ patients received either no treatment (n = 57), BMDJ surgery (n = 25), tooth extraction (n = 20), or root canal treatment (n = 11). Serum concentrations of RANTES/CCL5, C-reactive protein (CRP), and Tumor Necrosis Factor-α (TNF-α) were assessed before and after treatment (interventional group) and at the beginning and end of the study period (control group). Statistical analyses of the results were performed by the two-sample t-test and Bonferroni post hoc test with ANOVA for multiple comparisons.

Results

BMDJ were detected in all patients with 4.42 ± 2.75 BMDJ findings per patient. RANTES/CCL5 levels were significantly reduced by any treatment when compared to no treatment (p < 0.001; effect size d = 0.90). This effect was most pronounced in the BMDJ surgery group (p < 0.001; effect size d = 1.30). In contrast, RANTES/CCL5 serum concentrations further increased in untreated patients. Mean duration between pre- and post-treatment RANTES/CCL5 measurements was 22.86 ± 19.36 weeks, with no correlation with RANTES/CCL5 levels in any interventional group or in the total sample (p = 0.104).

Conclusion

BMDJ surgery, tooth extraction, and root canal treatment significantly reduce RANTES/CCL5 serum concentrations in BMDJ patients, with surgery being most beneficial. Further research is required to establish regular RANTES/CCL5 assessments as part of an improved diagnosis, monitoring, and evaluation of therapy success in BMDJ patients.

Proteomic Analysis of Mesenchymal Stromal Cells Secretome in Comparison to Leukocyte- and Platelet-Rich Fibrin

Secretomes of mesenchymal stromal cells (MSCs) are emerging as a novel growth factor (GF)-based strategy for periodontal and bone regeneration. The objective of this study was to compare the secretome of human bone marrow MSC (BMSC) to that of leukocyte- and platelet-rich fibrin (L-PRF), an established GF-based therapy, in the context of wound healing and regeneration. Conditioned media from human BMSCs (BMSC-CM) and L-PRF (LPRF-CM) were subjected to quantitative proteomic analysis using liquid chromatography with tandem mass spectrometry. Global profiles, gene ontology (GO) categories, differentially expressed proteins (DEPs), and gene set enrichment (GSEA) were identified using bioinformatic methods. Concentrations of selected proteins were determined using a multiplex immunoassay. Among the proteins identified in BMSC-CM (2157 proteins) and LPRF-CM (1420 proteins), 1283 proteins were common. GO analysis revealed similarities between the groups in terms of biological processes (cellular organization, protein metabolism) and molecular functions (cellular/protein-binding). Notably, more DEPs were identified in BMSC-CM (n = 550) compared to LPRF-CM (n = 118); these included several key GF, cytokines, and extracellular matrix (ECM) proteins involved in wound healing. GSEA revealed enrichment of ECM (especially bone ECM)-related processes in BMSC-CM and immune-related processes in LPRF-CM. Similar trends for intergroup differences in protein detection were observed in the multiplex analysis. Thus, the secretome of BMSC is enriched for proteins/processes relevant for periodontal and bone regeneration. The in vivo efficacy of this therapy should be evaluated in future studies.

Extraction Socket Augmentation with Autologous Platelet-Rich Fibrin (PRF): The Rationale for Socket Augmentation

After tooth extraction, the alveolar ridge undergoes a physiological process of remodelling and disuse atrophy. Socket augmentation (SA) has been shown to preserve alveolar bone volume in order to facilitate implant placement and reduce the need for staged grafting at a later date. Although autogenic grafting has been shown to be the gold standard in bone regeneration, it has significant disadvantages. To prevent post-extraction volumetric alterations and alveolar bone resorption occurring, alternative grafting materials, including xenografts, alloplasts, and allografts, have been used successfully in fresh extraction sites. However, these materials act mostly as bio-scaffolds and require a slower integration period of 6-8 months prior to implant placement. Recently, the use of autologous platelet-rich fibrin (PRF) has been advocated alongside socket augmentation as a method of bio-enhancement of healing of soft and hard tissues. PRF contains platelet-derived growth factors, hormones, and bioactive components such as cytokines that have been shown to promote angiogenesis and tissue regeneration during wound healing. The aim of this article is to review the evidence base for the SA technique Clinical benefits of SA will be discussed with a reference to two cases. Therefore, this narrative review will discuss the post-extraction bone changes, the importance of SA, and the bio-enhancement role of PRF in the management of extraction site defects when the alternative technique of immediate implant placement is not possible or contraindicated.

Does the Choice of Preparation Protocol for Platelet-Rich Fibrin Have Consequences for Healing and Alveolar Ridge Preservation After Tooth Extraction? A Meta-Analysis

PURPOSE

Multiple preparation protocols for platelet-rich fibrin (PRF) are in use today, and clinical results are often heterogeneous. This study analyzes the impact of the chosen PRF preparation protocol on 1) wound healing and 2) alveolar ridge preservation.

METHODS

For this systematic review and meta-analysis, eligible studies were identified in PubMed and Cochrane databases. Included were randomized controlled and controlled clinical trials with healthy patients treated with PRF after atraumatic tooth extraction compared to untreated socket(s), reporting at least one of the following outcome variables: pain, swelling, soft tissue healing, alveolar osteitis risk, horizontal and vertical bone loss, socket fill, and new bone formation. Main predictor variable was relative centrifugal force (RCF) comparing high RCF (high PRF), intermediate RCF (standard [S-PRF]), low RCF (advanced PRF), and various RCF settings (concentrated growth factor preparation [CGF]). The type of centrifugation tubes (silica-coated plastic and glass) was a secondary predictor. Weighted or standardized mean differences, risk ratio and corresponding 95% confidence intervals were calculated.

RESULTS

Forty studies published between 2012 and 2022 were selected. The pooled effects of all outcomes were significant against untreated sockets. Within the subgroups high PRF or advanced PRF had the lowest efficacy for many outcome parameters. Pain reduction (in visual analog scale units) was highest for S-PRF (-1.18 [-1.48, -0.88], P < .00001) and CGF (-1.03 [-1.16, -0.90], P < .001). The risk ratio of alveolar osteitis (0.09 [0.01, 0.69], P < .02) and soft tissue healing (standardized mean difference = 2.55 [2.06, 3.03], P < .001) were best for CGF. No subgroup differences were found for bone-related outcomes. No meaningful analysis of the tube material effect was possible.

CONCLUSION

This study confirms that PRF is associated with reduced postoperative complications but indicates that preparation protocol influences clinical outcomes. S-PRF and CGF protocols appear to be superior for several outcome parameters.

Effectiveness of Plasma-Rich Fibrin and De-Epithelialized Free Gingival Graft in the Treatment of Gingival Recessions

Introduction/Aim: Soft tissue dehiscences such as gingival recessions are a very common problem that we face in modern periodontics. This clinical study aimed to analyze the effectiveness of surgical procedures using a de-epithelialized gingival graft (DGG) combined with a coronally advanced flap and to evaluate the application of plasma-rich fibrin (PRF). Methods: The study included 40 teeth (20 patients) with Miller class I and II gingival recessions. Twenty recessions (20 patients) were treated utilizing the de-epithelialized gingival graft in combination with the coronally advanced flap, and on the opposite side of the jaw, the same number of recessions were treated utilizing plasma-rich fibrin combined with the coronally advanced flap. To evaluate tissue condition and the clinical parameters before and after the surgical procedure, the following parameters were used: the degree of epithelial attachment (DEA), the width of keratinized gingiva (WKG), and the vertical depth of recession (VDR). Results: based on the achieved results and the analysis of clinical parameters, a statistically significant reduction in the vertical depth of recession was proven in both groups, with very similar mean percentages of root coverage, with the difference being that the stability of the soft tissues of the treated region was more visible in the DGG. Conclusion: using modern surgical procedures allows the regeneration of not only the soft tissues but also deeper periodontal tissues.

GARP Regulates the Immune Capacity of a Human Autologous Platelet Concentrate

Autologous platelet concentrates, like liquid platelet rich fibrin (iPRF), optimize wound healing; however, the underlying immunological mechanisms are poorly understood. Platelets, the main cellular component of iPRF, highly express the protein, Glycoprotein A repetitions predominant (GARP), on their surfaces. GARP plays a crucial role in maintaining peripheral tolerance, but its influence on the immune capacity of iPRF remains unclear. This study analyzed the interaction of iPRF with immune cells implicated in the wound healing process (human monocyte derived macrophages and CD4⁺ T cells) and evaluated the distinct influence of GARP on these mechanisms in vitro. GARP was determined to be expressed on the surface of platelets and to exist as a soluble factor in iPRF. Platelets derived from iPRF and iPRF itself induced a regulatory phenotype in CD4⁺ T cells, shown by increased expression of Foxp3 and GARP as well as decreased production of IL-2 and IFN-γ. Application of an anti-GARP antibody reversed these effects. Additionally, iPRF polarized macrophages to a "M0/M2-like" phenotype in a GARP independent manner. Altogether, this study demonstrated for the first time that the immune capacity of iPRF is mediated in part by GARP and its ability to induce regulatory CD4⁺ T cells.

Autologous blood products: Usage and preparation protocols

FOCUSED CLINICAL QUESTION

What are the appropriate preparation protocols for autologous blood products to support their clinical utilization?

SUMMARY

Autologous blood products provide a unique clinical benefit. Their popularity among the professions is growing. However, as this is a rapidly evolving field, multiple modalities are presented within the literature. Frequently there is no demonstrated superiority to previous iterations. This brief review attempts to offer a concise chronology on their evolution, preparation, and where possible, evidence to support their clinical utilization.

CONCLUSIONS

The field of autologous blood products is expanding rapidly. These products appear to yield variable clinical benefits in specific indications. However, evidence supporting their universal application is scant, and the superiority of one formulation versus another is yet to be demonstrated.

Oro-Antral Fistulas and their Management: Our Experience

Oroantral fistula (OAF) is an epithelized, pathological communication between the maxillary antrum and oral cavity. The most common etiological factor is molar or premolar tooth extraction. The bone between maxillary sinus floor and posterior teeth is thin and occasionally the root apices of the posterior teeth reach the maxillary sinus, predisposing them to the formation of OAF. Other causes are bacterial or fungal infections, osteomyelitis, granulomatous diseases, Paget's disease, malignancy, maxillofacial trauma and iatrogenic. Small OAFs heal spontaneously but larger fistulas, persisting more than three weeks need to be closed. In repairing the persistent OAF, the maxillary sinus must be addressed. Maxillary sinusitis may lead to the failure of closure of the OAF. The basic modus operandi is clearance of disease from the sinus and covering the defect with a suitable graft. Various local and distant flaps are used to repair the OAF. We report three cases of OAF, managed by three different techniques. We also suggest a combined approach for large OAFs, repaired in 3 layers using septal cartilage, fat, and a buccal muco-periosteal advancement flap.

A Bibliometric Analysis of Platelet-Rich Fibrin in Dentistry

Platelet-rich fibrin (PRF), a second-generation platelet concentrate, has been widely recognized in numerous studies for its performance of wound healing and regeneration in dentistry. However, bibliometric analysis of PRF in dentistry is still scarce. Thus, this study aimed to conduct and delineate a bibliometric analysis of the application of PRF and its changing trend in dentistry. All papers concerning PRF up to 30 June 2022 were included in the literature search from the Web of Science Core Collection database. These data were then entered into Microsoft Excel, analyzed by the SAS statistical software, and visualized by the VOSviewer software. A total of 562 articles were retrieved following the exclusive criteria. The results demonstrated that the trend of annual publication increased continually (p for trend < 0.01), more notably in the last five years. The majority of the articles were original (58.01%), followed by reviews (17.08%), and case reports (10.14%). The three major study designs were clinical studies (20.11%), randomized controlled trials (17.62%), and review/meta-analysis (17.08%). PRF was most frequently employed in oral surgery (31.14%), periodontal regeneration (22.42%), and implant therapy (18.68%). Turkey (16.19%), India (12.28%) and China (7.12%) were the top 3 countries publishing PRF studies. By comparing the total number of publications, total citation counts and varying counting methods, a combination of numerous counting methods was suggested for use since each counting method yields different results. Taken together, we hope with these informative findings, researchers could focus on the future direction or advancement in PRF, laying a foundation for evidence-based dentistry.

Platelet-derived growth factors from a single donor by apheresis and one freeze-thaw cycle for treating medication-related osteonecrosis of the jaw

Aim: To assess whether the use of allogeneic platelet-derived growth factors could serve as a feasible, effective and safe biological therapy for the treatment of medication-related osteonecrosis of the jaw (MRONJ). Materials & methods: Patients with multiple myeloma and MRONJ were included and treated with allogeneic platelet-rich plasma, continued for between 6 and 18 weeks (mean: 9). Results: We observed a treatment success rate of 87.5% (p < 0.05). Assessing the association between healing and treatment duration, we observed a statistically significant relationship (χ² = 8.00; p = 0.018; Cramer's V = 1), confirming that healing was very closely related to the duration of the treatment. Conclusion: Allogeneic platelet-rich plasma could be a recommended treatment for MRONJ. Future research with a large sample to validate our findings is required.

Growth Factor Release within Liquid and Solid PRF

Aim: The purpose of this study was to obtain data concerning growth factor release within liquid and solid platelet-rich fibrin (PRF) matrices and to estimate the amount of potential interindividual variations as a basis for further preclinical and clinical trials. Therefore, we aimed to determine possible differences in the release of growth factors between liquid and solid PRF. Materials and Methods: Blood samples obtained from four subjects were processed to both liquid and solid PRF matrices using a standard centrifugation protocol. Five growth factors (vascular endothelial growth factor, VEGF; epidermal growth factor, EGF; platelet-derived growth factor-BB, PDGF-BB; transforming growth factor-β1, TGF-β1; and matrix metallopeptidase 9, MMP-9) have been evaluated at six time points by ELISA over a total observation period of 10 days (1 h, 7 h, 1 d, 2 d, 7 d, and 10 d). Results: Growth factor release could be measured in all samples at each time point. Comparing liquid and solid PRF matrices, no significant differences were detected (p > 0.05). The mean release of VEGF, TGFβ-1, PDGF-BB, and MMP-9 raised to a peak at time point five (day 7) in both liquid and solid PRF matrices. VEGF release was lower in liquid PRF than in solid PRF, whereas those of PDGF-BB and MMP-9 were higher in liquid PRF than in solid PRF at all time points. EGF had its peak release already at time point two after 7 h in liquid and solid matrices (hour 7 EGF solid: mean = 180 pg/mL, SD = 81; EGF liquid: mean = 218 pg/mL, SD = 64), declined rapidly until day 2, and had a second slight peak on day 7 in both groups (day 7 EGF solid: mean = 182 pg/mL, SD = 189; EGF liquid: mean = 81 pg/mL, SD = 70). Conclusions: This study detected growth factor release within liquid and solid PRF matrices with little variations. Further preclinical trials are needed to precisely analyze the growth factor release in larger samples and to better understand their effects on wound healing in different clinical indications.

Injectable platelet-rich fibrin as treatment for temporomandibular joint osteoarthritis: A randomized controlled clinical trial

The purpose of this study was to assess the treatment outcomes of intraarticular injection of injectable platelet-rich fibrin (i-PRF) after arthrocentesis in patients with temporomandibular joint osteoarthritis (TMJ-OA). Patients were randomly assigned to one of two treatment groups: those who received intraarticular injection of i-PRF after arthrocentesis procedure - the i-PRF group; and those who underwent the arthrocentesis procedure alone - the control group. The primary outcome variable was pain, the level of which was measured preoperatively and at 1, 2, 3, 6, and 12 months postoperatively. The secondary outcome variables included maximum mouth opening (MMO), and lateral and protrusive movements. Of the total of 36 patients, 18 were analyzed in the i-PRF group and 18 in the control group. There were significant differences between the groups in terms of pain levels and measurements of MMO, lateral movement, and protrusive movement over the 12 months of follow-up (p < 0.001). Significant increases in pain levels and decreases in measurements of MMO, lateral movement, and protrusive movement were observed in the control group from the 6th to 12th month postoperatively (p < 0.001). In contrast, no significant differences were found in both pain levels and measurements of MMO, lateral, and protrusive movements for the i-PRF group from the 2nd to the 12th month postoperatively. Within the limitations of the study it seems that intraarticular injection of i-PRF after arthrocentesis should be preferred whenever appropriate because when reducing pain intensity and improving functional jaw movement is the priority.

In Vitro and Ex Vivo Kinetic Release Profile of Growth Factors and Cytokines from Leucocyte- and Platelet-Rich Fibrin (L-PRF) Preparations

L-PRF is an autologous blood-derived biomaterial (ABDB) capable of releasing biologically active agents to promote healing. Little is known about its release profile of growth factors (GFs), cytokines, and MMPs. This study reported the in vitro and ex vivo release kinetics of GFs, cytokines, and MMPs from L-PRF at 6, 24, 72, and 168 h. The in vitro release rates of PDGF, TGF-β1, EGF, FGF-2, VEGF, and MMPs decreased over time with different rates, while those of IL-1β, IL-6, TNF-α, IL-8, and IL-10 were low at 6 h and then increased rapidly for up to 24 h and subsequently decreased. Of note, the release rates of the GFs followed first-order kinetics both in vitro and ex vivo. Higher rates of release were found ex vivo, suggesting that significant amounts of GFs were produced by the local cells within the wound. In addition, the half-life times of GFs locally produced in the wound, including PDGF-AA, PDGF-AB/BB, and VEGF, were significantly extended (p < 0.05). This work demonstrates that L-PRF can sustain the release of GFs and cytokines for up to 7 days, and it shows that the former can activate cells to produce additional mediators and amplify the communication network for optimizing the wound environment, thereby enhancing healing.

Utilizing 3D bioprinted platelet-rich fibrin-based materials to promote the regeneration of oral soft tissue

Oral soft tissue defects remain difficult to treat owing to the limited efficacy of available treatment materials. Although the injectable platelet-rich fibrin (i-PRF) is a safe, autologous source of high levels of growth factors that is often employed to promote the regeneration of oral soft tissue, its effectiveness is restrained by difficulties in intraoperative shaping together with the burst-like release of growth factors. We herein sought to develop a bioactive bioink composed of i-PRF, alginate and gelatin capable of promoting the regeneration of the oral soft tissue. This bioink was successfully applied in 3D bioprinting and exhibited its ability to be shaped to individual patient needs. Importantly, we were also able to significantly prolong the duration of multiple growth factors release as compared to that observed for i-PRF. The growth factor bioavailability was further confirmed by the enhanced proliferation and viability of printed gingival fibroblasts. When deployed in vivo in nude mice, this bioink was further confirmed to be biocompatible and to drive enhanced angiogenic activity. Together, these data thus confirm the successful production of an i-PRF-containing bioink, which is suitable for the individualized promotion of the regeneration of oral soft tissue.

Preparation, characterization and biological properties of a novel bone block composed of platelet rich fibrin and a deproteinized bovine bone mineral

Alveolar bone defects caused by tooth loss often lead to challenges in implant dentistry, with a need for development of optimal bone biomaterials to predictably rebuild these tissues. To address this problem, we fabricated a novel bone block using platelet-rich fibrin (PRF) and Deproteinized Bovine Bone Mineral (DBBM), and characterized their mechanical and biological properties. The bone block was prepared by mixing DBBM, Liquid-PRF, and Solid-PRF fragments in various combinations as follows: (1) BLOCK-1 made with Solid-PRF fragments + DBBM, (2) BLOCK-2 made with Liquid-PRF + DBBM, (3) BLOCK-3 made with Solid-PRF fragments + Liquid-PRF + DBBM. The time for solidification and the degradation properties were subsequently recorded. Scanning electron microscopy (SEM) and tensile tests were carried out to investigate the microstructure and mechanical properties of each block. The bioactivity of the three groups towards osteoblast differentiation was also evaluated by culturing cells with the conditioned medium from each of the three groups including cell proliferation assay, cell migration assay, alkaline phosphatase (ALP) staining, and alizarin red staining (ARS), as well as by real-time PCR for genes encoding runt-related transcription factor 2 (RUNX2), ALP, collagen type I alpha1(COL1A1) and osteocalcin (OCN). BLOCK-3 made with Solid-PRF fragments + Liquid-PRF + DBBM had by far the fastest solidification period (over a 10-fold increase) as well as the most resistance to degradation. SEM and tensile tests also revealed that the mechanical properties of BLOCK-3 were superior in strength when compared to all other groups and further induced the highest osteoblast migration and osteogenic differentiation confirmed by ALP, ARS and real-time PCR. PRF bone blocks made through the combination of Solid-PRF fragments + Liquid-PRF + DBBM had the greatest mechanical and biological properties when compared to either used alone. Future clinical studies are warranted to further support the clinical application of PRF bone blocks in bone regeneration procedures.

Tooth-Derived Granules in Combination with Platelet-Rich Fibrin (“Sticky Tooth”) in Socket Preservation: A Histological Evaluation

Background: The maintenance of ridge volume following tooth extraction has gained more importance in the last few years. This clinical study aimed to assess the impact of autologous dentin particles mixed with injectable platelet-rich fibrin (i-PRF) on a sticky tooth mixture for socket preservation in terms of consecutive need for horizontal guided bone regeneration and histological findings. Methods: Eight extraction sockets in seven patients were included in this study. Autologous dentin particles were mixed with PRF, filled in the sockets, and covered with a cross-linked collagen membrane exposed to the oral cavity and fixated by crisscross sutures. An orthopantomogram was taken before the first surgical procedure and a CBCT prior to static computer-aided implant surgery. At the time of implant placement, cores were harvested with the aid of a trephine for histological examinations for every preserved socket. Results: No further horizontal GBR intervention was required in any cases, and the histological findings were unremarkable. The new bone was mostly cancellous and in direct contact with the remaining dentin granules. Conclusions: Within the limits of this clinical study, it may be concluded that this method is valuable for socket preservation and obtaining vital and good quality bone structure. The sticky tooth technique seems to be very efficient despite the more complex equipment.

Role of platelet rich fibrin in the closure of oronasal fistula. A case report

An oronasal fistula is an abnormal opening connecting the oral cavity and the nose. They could occur as complications of oral and maxillofacial procedures. Oronasal fistulas (ONF) are challenging to repair optimally. The repair of a recurrent ONF is more of an enigma in cases where a small defect often requires an extensive surgery to close. Platelet rich fibrin (PRF) was described by Choukroun as a platelet concentrate from autologous blood which forms a single fibrin biomaterial after centrifugation. This haemostatic plug rich in growth factors is easy to prepare, manipulate; and adapt for soft and hard tissue healing. It has been utilized in the various fields of dentistry especially oral and maxillofacial surgery. Reports of role of PRF in the repair of ONF closure are scarce in literature especially in conjunction with other soft tissue flaps. This case report highlights that PRF can be used with success as an adjunct for the closure of ONF fistulas.

Efficacy of platelet-rich fibrin in promoting the healing of extraction sockets: a systematic review

PURPOSE

To address the focused question: in patients with freshly extracted teeth, what is the efficacy of platelet-rich fibrin (PRF) in the prevention of pain and the regeneration of soft tissue and bone compared to the respective control without PRF treatment?

METHODS

After an electronic data search in PubMed database, the Web of Knowledge of Thomson Reuters and hand search in the relevant journals, a total of 20 randomized and/or controlled studies were included.

RESULTS

66.6% of the studies showed that PRF significantly reduced the postoperative pain, especially in the first 1-3 days after tooth extraction. Soft tissue healing was significantly improved in the group of PRF compared to the spontaneous wound healing after 1 week (75% of the evaluated studies). Dimensional bone loss was significantly lower in the PRF group compared to the spontaneous wound healing after 8-15 weeks but not after 6 months. Socket fill was in 85% of the studies significantly higher in the PRF group compared to the spontaneous wound healing.

CONCLUSIONS

Based on the analyzed studies, PRF is most effective in the early healing period of 2-3 months after tooth extraction. A longer healing period may not provide any benefits. The currently available data do not allow any statement regarding the long-term implant success in sockets treated with PRF or its combination with biomaterials. Due to the heterogeneity of the evaluated data no meta-analysis was performed.

SB, Babu G, Vijayan V. Clinical Application of Platelet-Rich Fibrin in Pediatric Dentistry

Platelet-rich fibrin (PRF) is a fibrin matrix in which platelet cytokines, growth factors, and cells are trapped and may be released after a certain time and that can serve as a resorbable membrane. It can be obtained from blood with the help of a simple process. PRF is basically a concentrate of growth factors that promote wound healing and regeneration, which is used in various disciplines of dentistry to repair various lesions and regenerate dental and oral tissues. Although the use of PRF is well-documented, its use in pediatric dentistry remains unexplored, due to its restrictions and on account of the fact that it is a blood-derived product. PRF has been used globally to enhance tissue healing. This article provides an insight into the use of PRF in pediatric dentistry, its benefits, limitations, and recommendations.

Natural Polymers for the Maintenance of Oral Health: Review of Recent Advances and Perspectives

The success of modern dental treatment is strongly dependent on the materials used both temporarily and permanently. Among all dental materials, polymers are a very important class with a wide spectrum of applications. This review aims to provide a state-of-the-art overview of the recent advances in the field of natural polymers used to maintain or restore oral health. It focuses on the properties of the most common proteins and polysaccharides of natural origin in terms of meeting the specific biological requirements in the increasingly demanding field of modern dentistry. The use of naturally derived polymers in different dental specialties for preventive and therapeutic purposes has been discussed. The major fields of application cover caries and the management of periodontal diseases, the fabrication of membranes and scaffolds for the regeneration of dental structures, the manufacturing of oral appliances and dentures as well as providing systems for oral drug delivery. This paper also includes a comparative characteristic of natural and synthetic dental polymers. Finally, the current review highlights new perspectives, possible future advancements, as well as challenges that may be encountered by researchers in the field of dental applications of polymers of natural origin.

A standardized g-force allows the preparation of similar PRF qualities regardless of rotor angle

Platelet rich fibrin (PRF) is an autologous blood concentrate, that supports tissue regeneration. The effect of the centrifuge rotor angle in the fabrication of PRF is still not fully elucidated. The hypothesis of this study is: When applying the same g-force {relative centrifugal force (RCF)} and centrifugation time, PRF components and bioactivity are not modified using either a swing-out or fixed angle rotor. For this purpose, peripheral blood samples (five donors )were used to gain solid matrices (710 xg, 8 minutes) and liquid (44 xg, 8 minutes) PRF matrices using three different centrifuges (one fixed angle as a control; and two different swingout rotor centrifuges). The physical characteristics of the solid PRF were measured to evaluate the clot formation and cellular distribution. Liquid PRF was used to evaluate the cell number, bioactivity and influence on primary human osteoblasts and fibroblasts in vitro. Solid PRF clots were significantly larger in the group of fixed rotor centrifuges compared to either of the two evaluated swing-out rotor centrifuges. No differences were observed when evaluating the cellular distribution within the solid No statistically significant differences were documented in the cell's density in liquid PRF samples (platelets, lymphocytes, neutrophils, eosinophils, and basophils) among the differently gained PRF samples. No statistically significant differences were documented for the released growth factors (VEGF, EGF, TGF-β1) over 7 days. Primary human osteoblasts (pOBs) and primary human fibroblasts (pHFs) viability after treatment with PRF conditioned media showed no statistically significant differences between the evaluated groups. However, the number of adherent cells treated with PRF obtained with the use of the fixed angle rotor was significantly higher when compared to those treated with PRF obtained by using the swing-out rotors. The presented results confirmed that regardless of the centrifuge rotor used, the components and bioactivity of solid and liquid PRF matrices are modified by the applied RCF and centrifugation time. These findings are of great importance for highlighting the essential role of adapting the centrifugation protocols when using different centrifuges and to correctly report the used centrifugation protocols in scientific research to allow for reproducible results.

The effect of platelet-rich fibrin (PRF) on wound healing, adhesion, and hemostasis after endoscopic sinus surgery in patients with nasal polyposis

PURPOSE

Chronic rhinosinusitis (CRS) is one of the most common chronic diseases seen worldwide. Endoscopic sinus surgery (ESS) has become a widely accepted procedure for medically refractory chronic rhinosinusitis and nasal polyps. Prevention of revision surgery often depends on good wound healing and less adhesion formation. In recent years, the effects of platelet-rich fibrin (PRF) on tissue healing have been addressed in many surgical branches, especially for dental implant surgery and plastic surgery.

METHODS

This prospective study was conducted with 50 patients who underwent endoscopic sinus surgery for the diagnosis of nasal polyposis. While the middle meatus in one nasal cavity was filled with PRF and supported with Nasopore, only Nasopore was used in the other nasal cavity middle meatus. The patients were followed up clinically at weeks 1, 2, 3, 4, 8, and 12 postoperatively. The assessor determined the presence of adhesion, crusting, bleeding, frontal ostium stenosis, granulation, and infection, and if present, the grades of these complications were scored according to a questionnaire.

RESULTS

In our study, adhesion, infection, bleeding, granulation, and frontal ostium stenosis were less common in the PRF group, and a statistically significant difference was found between the groups.

CONCLUSION

In our study, better results were obtained in terms of adhesion, infection, bleeding, granulation, and frontal ostium stenosis after ESS as a result of the effects of PRF on wound healing. The application of PRF is an inexpensive and easy procedure. PRF can be a good alternative to other types of tampons after ESS.

Clinical outcomes of operative arthroscopy and temporomandibular medical infiltration with platelet-rich fibrin in upper and lower articular space

This study aims to describe the short-term therapeutic results of patients treated with operative arthroscopy and medical infiltration with platelet-rich fibrin in upper and lower articular space. The study design is descriptive observational with retrospective case series of patients with Wilkes II and III. These patients were managed with operative arthroscopy viscosupplementation with platelet-rich fibrin (PRF) and were followed up for up to 8 months to evaluate their response to treatment. 17 patients were included in the study. In the pre-surgical assessment (T1) mean VAS was 7.1 and MID was 22.2 mm. Eight months later (T4) a relevant improvement in both mentioned variables MID 38.2 ± 4.1 and VAS 1.1 ± 0.2 was observed. Regarding the reduction of pain, a significant improvement in symptoms were found, this being 84.6% ± 3.5% and in mandibular mobility satisfactory results were also obtained, improving in 41.7% ± 20.9%. Within the limitations of the study temporomandibular joint arthroscopy and medical infiltration platelet-rich fibrin viscosupplementation is a procedure of limited invasiveness that shows promising results.

History of autologous platelet-rich plasma: A short review

Background

Platelet‐rich plasma (PRP) is a medical material with numerous applications. It produces particularly spectacular effects when applied in cosmetic dermatology.

Aim

To illustrate the origin of the treatment.

Conclusion

The therapy originates from transfusiology, where it is applied as a concentrate of platelets to treat trombocytopenia. PRP treatment is 70 years old and has an increasing number of applications. PRP holds particular promise for cosmetic dermatology.

Platelet-rich fibrin as a treatment option for osteoradionecrosis: A literature review

The aim of this review is to establish the usefulness and effectiveness of using platelet-rich fibrin (PRF) in the treatment of osteoradionecrosis (ORN) lesions. A review of the literature was performed using keywords through the PubMed-Medline and Cochrane Library search engine. Inclusion criteria were: (1) original publication in either the French or the English language, (2) studies conducted in humans, (3) presence of ORN lesions following head and neck radiotherapy (RT), (4) use of PRF or derivates in the treatment of ORN lesions, (5) clinical variables and outcomes mentioned in the study. Overall, four case reports were retained. Two publications were removed from the initial seven results after application of the inclusion criteria. A recent randomised clinical trial was not considered since the group analysed the effectiveness of leukocyte-enriched Plasmas-Rich-Fibrin (LPRF) in preventing ORN, but not in treating it. Therefore, four publications were retained for analysis. Results suggest that using PRF as an adjunct to surgical therapy is beneficial in treating ORN lesions although no controlled studies were found. Therefore, additional controlled clinical studies are warranted to better define the effectiveness and recommendation of this approach.

Efficiency of advanced-PRF usage in the treatment of alveolar cleft with iliac bone graft: A retrospective study

The aim of this study was to evaluate the efficiency of a new alveolar bone grafting protocol using advanced-PRF (a-PRF) by comparing the volumes of newly formed bone after a bone graft combining autogenous iliac crest bone with either PRF or a-PRF. Patients presenting with unilateral or a bilateral alveolar cleft were included retrospectively in two groups: one group was grafted using cancellous iliac crest bone with PRF (PRF group), whereas for the other group the same procedure was followed using a-PRF (a-PRF group). CBCT scans were performed 3 months preoperatively and 6 months postoperatively. The volume of newly formed bone was measured by subtracting the postoperative cleft volume from the preoperative cleft volume. The mean volume of newly formed bone was compared between the two groups using Student's t-test. Twenty-four patients were included, with 12 allocated to each group. Forty-eight CBCT scans were analyzed. The mean volume of newly formed bone was 0.29 (±0.09) cm³ in the a-PRF group, versus 0.20 (±0.08) cm³ in the PRF group (Student's t-test, p = 0.024). The percentage of newly formed bone was 60.4 (±10.4) % in the a-PRF group versus 51.4 (±18.4) % in the PRF group (Student's t-test, p = 0.165). Our study demonstrated improved bone regeneration in the a-PRF group. While bearing in mind the limitations of this study, the a-PRF procedure should be adopted in cleft bone grafting whenever possible.

Ultrasonographic evaluation of the titanium-prepared platelet-rich fibrin effect in free gingival graft procedures

BACKGROUND

Complications after free gingival graft (FGG) operations are generally related to the donor site. The titanium-prepared, platelet-rich fibrin (T-PRF) placement in the donor site accelerate the wound healing and prevent postoperative complications such as pain and hemorrhage. We aim to evaluate the effect of T-PRF regarding vascularization and tissue thickness and to report the advantages of the ultrasonography (US) in FGG.

METHODS

Ten individuals were divided into two groups as T-PRF and control. While the T-PRF membrane was placed at the donor site in the T-PRF group, a gelatin sponge was placed in the control group. All patients underwent US examination in terms of vascularization and tissue thickness of left and right donor sites. The correlation between the right and left donor sites was analyzed with the Pearson correlation test. Tissue thicknesses and pulsatility index (PI) were analyzed with independent samples t-test. The results were evaluated statistically at the P <0.05 significance level.

RESULTS

The T-PRF group showed increased vascularity which can be interpreted to improve healing in soft tissue. However, not a difference, but a positively very high correlation was observed between the right and left tissue thicknesses (P = 0,00; r = +0902).

CONCLUSIONS

Evaluation of tissue thickness and vascularization density of donor sites with US not only increases clinical success rate but also reduces the risk of complications during surgery and postoperative pain in FGG. Studies evaluating T-PRF membrane as palatal dressing after FGG are only clinical, however, the efficiency of T-PRF was evaluated radiologically in this study for the first time.

Guided bone regeneration simultaneous with implant placement using bovine-derived xenograft with and without liquid platelet-rich fibrin: a randomized controlled clinical trial

OBJECTIVE

To assess augmentation success after guided bone regeneration (GBR) carried out simultaneously with implant placement using bovine-derived xenograft alone and in combination with liquid platelet-rich fibrin (liquid-PRF).

METHODS

This randomized controlled clinical trial was conducted on patients with horizontal bone deficiency in the posterior regions of the mandible. After implant placement, GBR procedures were randomly performed using liquid-PRF-enriched bovine-derived xenograft (for the test group) and with bovine-derived xenograft alone (for the control group). To assess the change in augmentation thickness, the primary outcome of the study, cone beam computed tomography was carried out at the implant sites on completion and 6 months after surgery. The secondary outcomes were marginal bone level and implant survival rate at prosthetic delivery and at 6 months, 1 year, and 2 years follow-up after loading. The significance level was set at p<0.05 for all analysis.

RESULTS

Twenty patients with 50 implants were analyzed for the test group and 20 patients with 48 implants for the control group. At 6 months postoperatively, the mean values of augmentation thickness were 1.63 ± 0.21 mm, 2.59 ± 0.34 mm, and 3.11 ± 0.36 mm for the test group and 1.34 ± 0.14 mm, 2.49 ± 0.24 mm, and 2.97 ± 0.24 mm for the control group at 2 mm, 4 mm, and 6 mm below to the implant shoulder (p < 0.001, p = 0.007, and p = 0.036, respectively). The mean marginal bone loss was found to be less than 1 mm for both study groups during the 2 years of follow-up after prosthetic loading. Implant survival rate was 100% for both study groups.

CONCLUSION

Bovine-derived xenograft alone and in combination with liquid-PRF are both successful in achieving bone augmentation around the implants and produce a small change in marginal bone level and a high implant survival rate after loading.

CLINICAL RELEVANCE

There is a lack of evidence in the literature regarding the augmentation success of liquid-PRF used in combination with bone graft substitutes. This study indicates that liquid-PRF could be used as a supportive material with bovine-derived xenograft in GBR procedures carried out simultaneously with implant placement.

The Role of Platelet-Rich Fibrin (PRF) in the Prevention of Medication-Related Osteonecrosis of the Jaw (MRONJ)

Dentoalveolar surgery is probably the major risk factor for MRONJ and for other complications following a tooth extraction, especially in patients affected by systemic diseases. The aim of this retrospective study is to evaluate whether a PRF plug inserted in the post extraction socket can prevent the onset of MRONJ. The patients were divided into two groups according to the surgical protocol that included the insertion or not of the PRF following the extraction and all the anamnestic, and clinical data were analyzed. In the control group, 5 patients developed MRONJ (19.23%) while in the study group, any case of MRONJ was reported. In the control group, patients who developed MRONJ had a CTX with less than 100 pg/mL (5 high-risk patients, Spearman's rank r = .547, p < .001). The use of platelet concentrates in patients with high risk of MRONJ is a user-friendly technique with an excellent cost-benefit ratio in oral surgery.

Evaluation of the Histomorphometric and Micromorphometric Performance of a Serum Albumin-Coated Bone Allograft Combined with A-PRF for Early and Conventional Healing Protocols after Maxillary Sinus Augmentation: A Randomized Clinical Trial

The aim of this study was to compare the microarchitecture of augmented bone following maxillary sinus augmentation (MSA) after healing periods of 3 (test) and 6 (control) months using the combination of advanced platelet-rich fibrin (A-PRF) and a serum albumin-coated bone allograft (SACBA). Twenty-six patients with 30 surgical sites who required two-stage MSA were enrolled and grafted with the combination of A-PRF and SACBAs. The surgical sites were randomly allocated to the test or control group. During implant site preparation, 17 bone core biopsy samples were collected from each study group for histological, histomorphometric and micromorphometric analysis. Resonance frequency analysis was performed at the time of implant placement and 6, 8, 10, and 12 weeks postoperatively. The percentage of newly formed bone was 44.89 ± 9.49% in the test group and 39.75 ± 8.15% in the control group (p = 0.100). The results of the µCT analysis showed no significant differences in morphometric parameters between the study groups. The implant stability quotient was not significantly different between the two groups at 10 and 12 weeks postoperatively. Based on these findings, the total treatment time may be reduced by 3 months with the use of A-PRF and SACBAs for two-stage MSA.

Possible Implications for Improved Osteogenesis? The Combination of Platelet-Rich Fibrin With Different Bone Substitute Materials

Bone substitute materials (BSM) are widely used in oral regeneration, but sufficient angiogenesis is crucial for osteogenesis. The combination of BSM with autologous thrombocyte concentrations such as platelet-rich fibrin (PRF) may represent a clinical approach to overcome this limitation. This study analyzes the early influence on osteoblast (HOB) in vitro. Here, four different BSM (allogeneic, alloplastic, and two of xenogeneic origin) were combined with PRF. After the incubation with osteoblasts for 24 h, cell viability, migration, and proliferation were assessed. Next, marker of proliferation, migration, and differentiation were evaluated on gene and protein levels in comparison to the native BSM and osteoblast alone. Addition of PRF increased viability for both the xenogeneic BSM (p = 0.0008, p = 0.032, respectively) in comparison to HOB and vs. native BSM (p = 0.008), and led to a tendency for increased cell proliferation and migration for all BSM (each p > 0.05). On gene basis, allogeneic and alloplastic BSM displayed a significantly increased RUNX2 expression (each p = 0.050). Expression of alkaline phosphatase for alloplastic (p = 0.050) and collagen-1 for xenogeneic BSM (p = 0.05) were significantly increased in combination with PRF. In addition, bone morphogenic protein was expressed significantly higher when xenogeneic material was combined with PRF in comparison to HOB alone (each p = 0.05). In summary, the combination of PRF with different BSM increases initial viability and may influence early proliferation and migration potential of osteoblast via RUNX2, alkaline phosphatase, collagen, and BMP2 especially in combination with alloplastic and xenogeneic BSM. Biofunctionalization of BSM using PRF might improve osteogenesis and extend the range of indications.

Biologization of Pcl-Mesh Using Platelet Rich Fibrin (Prf) Enhances Its Regenerative Potential In Vitro

INTRODUCTION

Resorbable synthetic scaffolds are promising for different indications, especially in the context of bone regeneration. However, they require additional biological components to enhance their osteogenic potential. In addition to different cell types, autologous blood-derived matrices offer many advantages to enhance the regenerative capacity of biomaterials. The present study aimed to analyze whether biologization of a PCL-mesh coated using differently centrifuged Platelet rich fibrin (PRF) matrices will have a positive influence on primary human osteoblasts activity in vitro. A polymeric resorbable scaffold (Osteomesh, OsteoporeTM (OP), Singapore) was combined with differently centrifuged PRF matrices to evaluate the additional influence of this biologization concept on bone regeneration in vitro. Peripheral blood of three healthy donors was used to gain PRF matrices centrifuged either at High (710× g, 8 min) or Low (44× g, 8 min) relative centrifugal force (RCF) according to the low speed centrifugation concept (LSCC). OP-PRF constructs were cultured with pOBs. POBs cultured on the uncoated OP served as a control. After three and seven days of cultivation, cell culture supernatants were collected to analyze the pOBs activity by determining the concentrations of VEGF, TGF-β1, PDGF, OPG, IL-8, and ALP- activity. Immunofluorescence staining was used to evaluate the Osteopontin expression of pOBs. After three days, the group of OP+PRFLow+pOBs showed significantly higher expression of IL-8, TGF-ß1, PDGF, and VEGF compared to the group of OP+PRFHigh+pOBs and OP+pOBs. Similar results were observed on day 7. Moreover, OP+PRFLow+pOBs exhibited significantly higher activity of ALP compared to OP+PRFHigh+pOBs and OP+pOBs. Immunofluorescence staining showed a higher number of pOBs adherent to OP+PRFLow+pOBs compared to the groups OP+PRFHigh+pOBs and OP+pOBs. To the best of our knowledge, this study is the first to investigate the osteoblasts activity when cultured on a PRF-coated PCL-mesh in vitro. The presented results suggest that PRFLow centrifuged according to LSCC exhibits autologous blood cells and growth factors, seem to have a significant effect on osteogenesis. Thereby, the combination of OP with PRFLow showed promising results to support bone regeneration. Further in vivo studies are required to verify the results and carry out potential results for clinical translation.

Effect of injectable platelet-rich fibrin (i-PRF) in accelerating orthodontic tooth movement : A randomized split-mouth-controlled trial

BACKGROUND

The role of platelet-rich fibrin (PRF) in accelerating orthodontic tooth movement has been controversially discussed in available clinical studies.

OBJECTIVE

To investigate the effectiveness of i‑PRF in accelerating maxillary canine retraction.

MATERIALS AND METHODS

A split-mouth design was applied in 21 participants (6 men, 15 women; mean age: 20.85 ± 3.85 years) whose class II division I malocclusion required the extraction of both maxillary first premolars. The right and left canines were randomized into intervention and control sides. After the initial leveling and alignment phase and immediately before canine retraction, i‑PRF obtained from the brachial vein was injected into the mucosa on the buccal and palatal aspects of the intervention sides. The injection was repeated one month later. Study casts were taken at the initiation of canine retraction (T0) and at monthly visits up to 5 months (T1 through T5). The paired t‑test was used to compare the total and monthly rates of canine retraction, canine rotation, and anchorage loss.

RESULTS

The average rates of canine retraction were greater on the experimental side at T2, T3, and T4, but this difference with the control side was statistically significantly different only at T2 (P < 0.05). Differences in canine rotation and anchorage loss were not statistically significant.

CONCLUSION

The rates of canine retraction following the injection of platelet-rich fibrin were not statistically significantly greater on the experimental than the control sides except at the second month (T2). This apparently transient rate of tooth movement indicates that repeated injections might be needed for sustained effects, a premise meriting more focused research.

Does Platelet-Rich Fibrin Enhance the Early Angiogenetic Potential of Different Bone Substitute Materials? An In Vitro and In Vivo Analysis

The impaired angiogenic potential of bone substitute materials (BSMs) may limit regenerative processes. Therefore, changes in the angiogenetic properties of different BSMs in combination with platelet-rich fibrin (PRF) in comparison to PRF alone, as well as to native BSMs, were analyzed in vitro and in vivo to evaluate possible clinical application. In vitro, four BSMs of different origins (allogeneic, alloplastic, and xenogeneic) were biofunctionalized with PRF and compared to PRF in terms of platelet interaction and growth factor release (vascular endothelial growth factor (VEGF), tissue growth factor ß (TGFß) and platelet-derived growth factor (PDGF)) after 15 min. To visualize initial cell–cell interactions, SEM was performed. In vivo, all BSMs (±PRF) were analyzed after 24 h for new-formed vessels using a chorioallantoic membrane (CAM) assay. Especially for alloplastic BSMs, the addition of PRF led to a significant consumption of platelets (p = 0.05). PDGF expression significantly decreased in comparison to PRF alone (all BSMs: p < 0.013). SEM showed the close spatial relation of each BSM and PRF. In vivo, PRF had a significant positive pro-angiogenic influence in combination with alloplastic (p = 0.007) and xenogeneic materials (p = 0.015) in comparison to the native BSMs. For bio-activated xenogeneic BSMs, the branching points were also significantly increased (p = 0.005). Finally, vessel formation was increased for BSMs and PRF in comparison to the native control (allogeneic: p = 0.046; alloplastic: p = 0.046; and xenogeneic: p = 0.050). An early enhancement of angiogenetic properties was demonstrated when combining BSMs with PRF in vitro and led to upregulated vessel formation in vivo. Thus, the use of BSMs in combination with PRF may trigger bony regeneration in clinical approaches.

Injectable platelet-rich fibrin for facial rejuvenation: A prospective, single-center study

BACKGROUND

Autologous platelet-derived preparations have been used in many surgical fields to improve healing outcomes, with benefits reported in several aesthetic indications.

AIMS

This single-center, prospective, uncontrolled study evaluated the efficacy of injectable platelet-rich fibrin (i-PRF) for facial skin rejuvenation using an objective skin analysis system and validated patient-reported outcome measures.

PATIENTS/METHODS

PRF^® PROCESS system technology was used to prepare i-PRP. Eleven healthy female individuals were included in the study and over 3-months received monthly intradermal injections of i-PRF in 3 facial regions: malar areas (1 mL each side), nasolabial fold (0.5 mL each side), and upper lip skin above the vermilion border (1 mL). The efficacy of the procedures was assessed by objective skin analysis (VISIA^® ) and a subjective patient-reported outcome (FACE-Q) assessment at baseline and after 3 months.

RESULTS

A significant improvement in skin surface spots (P = .01) and pores (P = .03) was seen at 3-months follow-up. Other variables, such as skin texture, wrinkles, ultraviolet spots, and porphyrins, showed a numerical improvement. FACE-Q scales that measure satisfaction with appearance all showed a significant improvement from baseline, including satisfaction with skin (P = .002), satisfaction with facial appearance (P = .025), satisfaction with cheeks (P = .001), satisfaction with lower face and jawline (P = .002), and satisfaction with lips (P = .04). No major adverse effects were reported.

CONCLUSIONS

A series of three i-PRF injections resulted in significant rejuvenation of the face skin at 3-month follow-up, as shown by improved skin analysis parameters and patient self-assessment scores.