Biofunctionalized hydrogel composed of genipin-crosslinked gelatin/hyaluronic acid incorporated with lyophilized platelet-rich fibrin for segmental bone defect repair.

Segmental bone defects can arise from trauma, infection, metabolic bone disorders, or tumor removal. Hydrogels have gained attention in the field of bone regeneration due to their unique hydrophilic properties and the ability to customize their physical and chemical characteristics to serve as scaffolds and carriers for growth factors. However, the limited mechanical strength of hydrogels and the rapid release of active substances have hindered their clinical utility and therapeutic effectiveness. With ongoing advancements in material science, the development of injectable and biofunctionalized hydrogels holds great promise for addressing the challenges associated with segmental bone defects. In this study, we incorporated lyophilized platelet-rich fibrin (LPRF), which contains a multitude of growth factors, into a genipin-crosslinked gelatin/hyaluronic acid (GLT/HA-0.5 % GP) hydrogel to create an injectable and biofunctionalized composite material. Our findings demonstrate that this biofunctionalized hydrogel possesses optimal attributes for bone tissue engineering. Furthermore, results obtained from rabbit model with segmental tibial bone defects, indicate that the treatment with this biofunctionalized hydrogel resulted in increased new bone formation, as confirmed by imaging and histological analysis. From a translational perspective, this biofunctionalized hydrogel provides innovative and bioinspired capabilities that have the potential to enhance bone repair and regeneration in future clinical applications.

The effect of vitamin E incorporated into injectable platelet-rich fibrin on orthodontic tooth movement in rabbits.

To evaluate the effects of injectable platelet fibrin (iPRF) and combined vitamin E-iPRF on orthodontic tooth movement (OTM) rates in rabbits, 35 male New Zealand white rabbits were involved in this study using splitmouth design. OTM was carried out on the mandibular first premolar using 100g nickel titanium closing coil. Right side served as study group, isolated iPRF in one group and combined vitamin E-iPRF in other group was injected buccally and lingually (iPRF group, Vit E-iPRF group), and left side acted as positive control group (CG) by injecting normal saline (positive CG). The rate of OTM was measured using intra-oral scanner on days 7,14 and 21. Histological and Micro CT scan were examined on days 0, 7, 14 and 21. The iPRF and combined Vitamin E-iPRF demonstrated significant greater rate of OTM on days 7 and 14 in comparison to control group, only significant differences between iPRF and combined vitamin E-iPRF were seen on day 14. In all time intervals as compared to the CG, the number of osteoclasts was significantly higher in the isolated iPRF and combined vitamin E-iPRF groups. Significant reduction in bone volume fraction (BV/TV) was demonstrated in iPRF and combined vitamin E-iPRF groups in all time points, however, non-significant differences were found in trabecular thickness (Tb.Th) and trabecullar separation (Tb.Sp). Local injection of iPRF and combined vitamin E-iPRF showed temporary increase in the rate of OTM.

The effect of titanium-platelet rich fibrin on periodontal intrabony defects: A randomized controlled split-mouth clinical study.

This study aimed to determine the contribution of titanium prepared platelet-rich fibrin (T-PRF) with open flap debridement (OFD) on clinical, biochemical and radiographic measurements of periodontal regeneration. Twenty periodontitis patients with bilateral intrabony defects and stage III grade A periodontitis were included in the study. A total of 40 defects were randomly selected for OFD alone (control group, n = 20) or combined OFD+ T-PRF (test group, n = 20). Clinical and radiographic parameters (at baseline and nine months after surgery), and growth factor levels in gingival crevicular fluid (at baseline and at two, four, six, and twelve weeks after surgical treatment) were also evaluated. Considering the clinical parameters, alterations in probing pocket depth, gingival marginal level and clinical endpoint in the test regions treated with T-PRF significantly improved (P<0.05). Fibroblast growth factor-2 and platelet-derived growth factor-BB levels between the two groups in the second and fourth weeks were also significantly different (P<0.05). Furthermore, the receptor activator of nuclear factor κB ligand/osteoprotegerin ratio between the groups was significantly different in the second, fourth, sixth, and twelfth weeks (P<0.05). The bone-filling rate was also significantly greater in the test group than in the control group (P <0.001). Compared with OFD alone, combining T-PRF with the procedure was more successful with regards to clinical, radiographic, and biochemical measurements of periodontal regeneration.

Efficacy of autogenous platelet concentrates in immediate implant therapy: A systematic review and meta-analysis of prospective controlled clinical trials.

PURPOSE: To provide an overview of the outcomes of the use of autogenous platelet concentrates in immediate implant placement. MATERIALS AND METHODS: Based on an a priori protocol, a systematic search was performed of the National Library of Medicine (MEDLINE via PubMed), Embase and Scopus databases. Randomised and non-randomised controlled clinical trials on immediate implant placement including at least one study arm with use of platelet-rich fibrin or platelet-rich plasma as a gap filler between immediately placed implants and the alveolar bone were included. A random-effects meta-analysis model was built to assess the primary outcomes of marginal bone loss and probing pocket depths between test (platelet concentrates) and control (no graft or other graft materials) groups. A risk of bias assessment was performed and the Grading of Recommendations Assessment, Development and Evaluation approach was used to assess the certainty of evidence. RESULTS: A total of 20 trials (595 immediate implants placed in 454 individuals) were included in the meta-analytic model. Based on the data from studies with a minimum post-prosthetic loading period of 6 months after immediate implant placement, overall, the application of platelet concentrates was associated with significantly lower marginal bone loss and probing pocket depth compared to the control groups (mean difference -0.36 mm; P < 0.01 and mean difference -0.47 mm; P < 0.01, respectively). No additional benefit of application of platelet concentrates was detected regarding primary stability of immediate implants. Subgroup analysis revealed significantly lower marginal bone loss with xenogeneic bone alone compared to platelet concentrates alone as grafting material in immediate implant placement (mean difference 0.66 mm; P < 0.01). Evidence on soft tissue outcomes and aesthetic parameters was scarce. CONCLUSIONS: A low level of certainty based on the Grading of Recommendations Assessment, Development and Evaluation approach indicates superior outcomes in terms of marginal bone loss and probing pocket depth in immediate implant placement with the use of platelet concentrates versus no graft. Future research should be tailored towards a standardised protocol for preparation of platelet concentrates and inclusion of soft tissue and aesthetic outcomes as well.

[Autologous platelet concentrates in regenerative dentistry - A narrative literature review. Part II: clinical application of PRF in periodontology and implantology].

The clinical impact of platelet-rich fibrin (PRF) and plasma rich in growth factors (PRGF®) respectively has been studied extensively in the field of regenerative dentistry during the last two decades. Literature supports evidence for additional benefits in regenerative periodontal therapy, alveolar ridge preservation, management of extraction sockets, implantology including guided bone regeneration as well as defect management in oral surgery. Regarding gingival wound healing and soft tissue regeneration, there is sufficient evidence for their positive effects which have been confirmed in several systematic reviews. The effects seem less clear in conjunction with osseous regenerative treatments, where the inter-study heterogenity in terms of different PRF-protocols, indications and application forms might hinder a systematic comparison. Nevertheless there is evidence that PRF might have beneficial effects on hard-tissue or its regeneration respectively.For being able to facilitate conclusions in systematic reviews, precise reporting of the used PRF-protocols is mandatory for future (clinical) research in the field of autologous platelet concentrates.

[Autologous platelet concentrates in regenerative dentistry - A narrative literature review. Part I: Theoretical and legal aspects of the PR(G)F application].

The use of autologous platelet concentrates (APC) such as platelet-rich fibrin (PRF) and/or plasma rich in growth factors (PRGF®) is considered an established treatment modality in re-generative dentistry. The possibility of delivering growth factors over aclinically relevant time of several days seems particularly interesting in the context of wound healing.The growing body of evidence in the field of APC requires a continuous and actual knowledge of the literature for being able to make evidence-based treatment recommendations with a realistic assessment of possible advantages of this technology.PR(G)F can be applied in solid or liquid form, pure or in combination with other biomaterials. Both appear to be reasonable, depending on the clinical indication and/or desired treatment outcomes. Because of the many different factors that can affect the PR(G)F products final characteristics, a basic understanding of these parameters is desirable for choosing the most suitable product and/or optimizing its clinical application. This review aims to provide an over-view of relevant theoretical, practical, legal and biologic aspects of APCs.

Novel approach to soft tissue regeneration: in vitro study of compound hyaluronic acid and horizontal platelet-rich fibrin combination.

OBJECTIVE: This study aims to develop a compound biomaterial to achieve effective soft tissue regeneration. METHODOLOGY: Compound hyaluronic acid (CHA) and liquid horizontal-platelet-rich fibrin (H-PRF) were mixed at a ratio of 1:1 to form a CHA-PRF gel. Human gingival fibroblasts (HGFs) were used in this study. The effect of CHA, H-PRF, and the CHA-PRF gel on cell viability was evaluated by CCK-8 assays. Then, the effect of CHA, H-PRF, and the CHA-PRF gel on collagen formation and deposition was evaluated by qRT‒PCR and immunofluorescence analysis. Finally, qRT‒PCR, immunofluorescence analysis, Transwell assays, and scratch wound-healing assays were performed to determine how CHA, H-PRF, and the CHA-PRF gel affect the migration of HGFs. RESULTS: The combination of CHA and H-PRF shortened the coagulation time of liquid H-PRF. Compared to the pure CHA and H-PRF group, the CHA-PRF group exhibited the highest cell proliferation at all time points, as shown by the CCK-8 assay. Col1a and FAK were expressed at the highest levels in the CHA-PRF group, as shown by qRT‒PCR. CHA and PRF could stimulate collagen formation and HGF migration, as observed by fluorescence microscopy analysis of COL1 and F-actin and Transwell and scratch healing assays. CONCLUSION: The CHA-PRF group exhibited greater potential to promote soft tissue regeneration by inducing cell proliferation, collagen synthesis, and migration in HGFs than the pure CHA or H-PRF group. CHA-PRF can serve as a great candidate for use alone or in combination with autografts in periodontal or peri-implant soft tissue regeneration.

Evaluation optimum ratio of synthetic bone graft material and platelet rich fibrin mixture in a metal 3D printed implant to enhance bone regeneration.

BACKGROUND: This study aims to evaluate the optimal ratio of synthetic bone graft (SBG) material and platelet rich fibrin (PRF) mixed in a metal 3D-printed implant to enhance bone regeneration. METHODS: Specialized titanium hollow implants (5 mm in diameter and 6 mm in height for rabbit; 6 mm in diameter and 5 mm in height for pig) were designed and manufactured using 3D printing technology. The implants were divided into three groups and filled with different bone graft combinations, namely (1) SBG alone; (2) PRF to SBG in 1:1 ratio; (3) PRF to SBG in 2:1 ratio. These three groups were replicated tightly into each bone defect in distal femurs of rabbits (nine implants, n = 3) and femoral shafts of pigs (fifteen implants, n = 5). Animal tissue sections were obtained after euthanasia at the 8th postoperative week. The rabbit specimens were stained with analine blue, while the pig specimens were stained with Masson-Goldner's trichrome stain to perform histologically examination. All titanium hollow implants were well anchored, except in fracture specimens (three in the rabbit and one fracture in the pig). RESULT: Rabbit specimens under analine blue staining showed that collagen tissue increased by about 20% and 40% in the 1:1 ratio group and the 2:1 ratio group, respectively. Masson-Goldner's trichrome stain results showed that new bone growth increased by 32% in the 1:1 ratio PRF to SBG, while - 8% in the 2:1 ratio group. CONCLUSION: This study demonstrated that placing a 1:1 ratio combination of PRF and SBG in a stabilized titanium 3D printed implant resulted in an optimal increase in bone growth.

A randomised Trial of Autologous Blood products, leukocyte and platelet-rich fibrin (L-PRF), to promote ulcer healing in LEprosy: The TABLE trial.

INTRODUCTION: Autologous blood products like Platelet Rich Plasma (PRP) and Leukocyte and Platelets Rich Fibrin (L-PRF) have been used for many years across many types of skin ulcers. However, the effectiveness of autologous blood products on wound healing is not well established. METHODS: We evaluated the 'second generation' autologous product- Leukocyte and Platelet- Rich Fibrin (L-PRF). Our trial was undertaken on patients suffering from neuropathic leprosy ulcers at the Anandaban hospital which serves the entire country of Nepal. We conducted a 1:1 (n = 130) individually randomised trial of L-PRF (intervention) vs. normal saline dressing (control) to compare rate of healing and time to complete healing. Rate of healing was estimated using blind assessments of ulcer areas based on three different measurement methods. Time to complete healing was measured by the local unblinded clinicians and by blind assessment of ulcer images. RESULTS: The point estimates for both outcomes were favourable to L-PRF but the effect sizes were small. Unadjusted mean differences (intervention vs control) in mean daily healing rates (cm2) were respectively 0.012 (95% confidence interval 0.001 to 0.023, p = 0.027); 0.016 (0.004 to 0.027, p = 0.008) and 0.005 (-0.005 to 0.016, p = 0.313) across the three measurement methods. Time to complete healing at 42 days yielded Hazard Ratios (unadjusted) of 1.3 (0.8 to 2.1, p = 0.300) assessed by unblinded local clinicians and 1.2 (0.7 to 2.0, p = 0.462) on blind assessment. CONCLUSION: Any benefit from L-PRF appears insufficient to justify routine use in care of neuropathic ulcers in leprosy. TRIAL REGISTRATION: ISRCTN14933421. Date of trial registration: 16 June 2020.

Platelet-rich fibrin as an apical barrier for MTA placement in the treatment of teeth with open apices: a pilot study.

OBJECTIVE: The aim of the present pilot study was to assess the effectiveness of the platelet-rich fibrin (PRF) apical barrier for the placement of MTA for the treatment of teeth with periapical lesions and open apices. METHODS: A total of thirty teeth on twenty-eight patients with open apices and periapical periodontitis were enrolled and divided into two groups in the present pilot study. In the PRF group (fourteen teeth in thirteen patients), nonsurgical endodontic treatment was performed using PRF as an apical matrix, after which the apical plug of the MTA was created. For the non-PRF group (fourteen teeth in fourteen patients), nonsurgical endodontic therapy was performed using only the MTA for an apical plug with no further periapical intervention. Clinical findings and periapical digital radiographs were used for evaluating the healing progress after periodic follow-ups of 1, 3, 6, and 9 months. The horizontal dimension of the periapical lesion was gauged, and the changes in the dimensions were recorded each time. The Friedman test, Dunn-Bonferroni post hoc correction, and Mann-Whitney U test were used for statistical analysis, with P < 0.05 serving as the threshold for determining statistical significance. RESULTS: All patients in both groups in the present pilot study had no clinical symptoms after 1 month, with a significant reduction in the periapical lesion after periodic appointments. The lesion width of the PRF group was significantly smaller than that of the non-PRF group in the sixth and ninth month after treatment. CONCLUSIONS: PRF is a promising apical barrier matrix when combined with MTA for the treatment of teeth with open apices and periapical periodontitis. Small number of study subjects and the short time of follow-up period limit the generalizability of these results. TRIAL REGISTRATION: TCTR, TCTR20221109006. Registered 09 November 2022 - Retrospectively registered, https://www.thaiclinicaltrials.org/show/TCTR20221109006 .

Treatment of multiple adjacent gingival recessions using leucocyte- and platelet-rich fibrin with coronally advanced flap: a 12-month split-mouth controlled randomized clinical trial.

OBJECTIVE: This split-mouth randomized study aimed to assess efficacy of leucocyte-platelet-rich fibrin (L-PRF) versus connective tissue graft (CTG) in achieving root coverage (RC) for multiple adjacent gingival recessions (MAGRs) throughout 12-month period. MATERIALS AND METHODS: The study enrolled 59 teeth from 12 patients with Miller Class I MAGRs ≥ 2 mm on bilateral or contralateral sides. Patients were randomly assigned to receive coronally advanced flap (CAF) with either CTG (control) or L-PRF (test) treatment. Various parameters, including plaque and gingival index, clinical attachment level, recession depth, probing depth, recession width (RW), papilla width (PW), keratinized tissue width (KTW), gingival thickness (GT), percentage of RC, complete root coverage (CRC), and location of the relative gingival margin concerning the cemento-enamel junctions (GMCEJ) after CAF, were recorded at baseline, 3-, 6-, and 12-months post-surgery. On June 29, 2021 the study was registred to ClinicalTrials.gov (NCT04942821). RESULTS: Except KTW and GT gain, all clinical parameters, RC, and CRC were similar between the groups at all follow-up periods (p > 0.05). The higher GT and KTW gains were detected in the control group compared to test group at 12 months (p < 0.05). Both RC and CRC were positively associated with initial PW and GMCEJ, but negatively with initial RW (p < 0.05). CONCLUSIONS: The current study concludes that L-PRF were equally effective as CTG in treating MAGRs in terms of RC and CRC. Additionally, RC and CRC outcomes appeared to be influenced by GMCEJ, PW, and RW. CLINICAL RELEVANCE: L-PRF could represent a feasible substitute for CTG in treating MAGRs.

Comparison of growth factor levels in injectable platelet-rich fibrin obtained from healthy individuals and patients with chronic periodontitis: a pilot study.

BACKGROUND: This study aimed to assess and compare the concentrations of growth factors, white blood cells (WBCs), and platelets in injectable platelet-rich fibrin (i-PRF) derived from people with healthy periodontal conditions and those with chronic periodontitis. METHODS: Venous blood samples were obtained from 30 patients diagnosed with chronic periodontitis (test group) and 30 participants with healthy periodontal conditions (control group). The i-PRF was then acquired from centrifuged blood. The growth factors (VEGF, IGF-1, TGF-ß1, PDGF-BB and EGF) released from the i-PRF samples were compared between groups with ELISA testing. The amounts of WBCs and platelets were also compared. RESULTS: No significant differences in the concentrations of growth factors were found between the groups (the mean values for the control and test groups were, respectively: IGF: 38.82, 42.46; PDGF: 414.25, 466.28; VEGF: 375.69, 412.18; TGF-ß1: 21.50, 26.21; EGF: 138.62, 154.82). The test group exhibited a significantly higher WBC count than the control group (8.80 vs. 6.60, respectively). However, the platelet count did not show a statistically significant difference between the groups (control group 242.0 vs. test group 262.50). No significant correlation was observed between WBC count and growth factor level in either group. CONCLUSIONS: The growth factor levels in i-PRFs did not exhibit significant difference between the two groups. This suggests that the levels of these growth factors may be unaffected by the periodontal disease.

Vestibular Incision Subperiosteal Tunneling Approach (VISTA) with Platelet-Rich Fibrin (PRF) vs VISTA Alone in Multiple Recession Treatment: A Split-Mouth Randomized Clinical Trial.

Gingival recession treatment is one of the major clinical challenges in periodontics, and various surgical techniques have been proposed to correct it. Most of these techniques are suitable for isolated recession sites and involve harvesting an autogenous tissue graft, which increases patient morbidity and might result in inferior esthetics due to incision design. This study assessed the benefit of adding platelet-rich fibrin (PRF) to the vestibular incision subperiosteal tunneling approach (VISTA) in treating multiple gingival recession compared to using VISTA alone. A total of 41 teeth with Miller Class I and II defects were randomized in a split-mouth design. Multiple clinical parameters were tested, including the change in gingival thickness over time, keratinized tissue width, and gingival phenotype (using the transparency of a periodontal probe). Patient-centered outcomes were also assessed via visual analog scale. Multiple Miller Class I and II recessions in the maxilla can be effectively treated with VISTA. However, when used in conjunction with PRF, no significant differences were detected in any parameter. VISTA has been shown to be associated with a low level of postsurgical pain for patients and can be used for patients with high esthetic demands.

Performance of multiple therapeutic approaches for palatal wound healing after soft tissue graft removal - an overview of systematic reviews.

OBJECTIVE: To overview the literature to answer the following question: "What is the performance of different therapies on wound healing and postoperative discomfort after palatal ASTG removal?" METHODS: SRs that evaluated the wound healing (WH), postoperative pain, bleeding, and analgesic consumption of patients submitted to de-epithelialized/free gingival grafts (FGG) or subepithelial connective tissue grafts (SCTG) removed from the palate were included. The searches were conducted on six white and two gray databases up to December 2023. Methodological quality was evaluated through AMSTAR 2. The synthesis of results was described as a narrative analysis. RESULTS: Ten SRs (involving 25 randomized clinical trials) related to low-level laser therapy (LLLT) (3), platelet-rich fibrin (PRF) (4), cyanoacrylate tissue adhesives (CTA) (2), and ozone therapy (OT) (1) were included in this overview. All techniques demonstrated improvements in WH. LLT, PRF, and CTA reduced pain and analgesic consumption. PRF and CTA reduced bleeding. Regarding methodological quality, the SRs were classified as critically low (2), low (5), moderate (2), or high quality (1). CONCLUSIONS: In SRs related to LLLT, PRF, CTA, and OT, the use of different therapies after palatal ASTG removal improved WH and postoperative discomfort. Due to the studies' low methodological quality and high heterogeneity, data should be interpreted with caution. CLINICAL RELEVANCE: The present overview compiles the evidence of SRs related to different therapies for WH and patients' postoperative experience and reveals that different treatments can significantly improve the clinical outcomes of patients who require ASTG removal for periodontal or peri-implant surgeries. REGISTRATION: PROSPERO registration number: CRD42022301257.

Use of platelet- and leukocyte-rich fibrin (L-PRF) as a healing agent in the postoperative period of third molar removal surgeries: a systematic review.

OBJECTIVE: The aim of this study was to analyze the effectiveness of L-PRF as a healing agent in the postoperative period of third molar extraction surgeries, as well as to investigate secondary effects, such as the reduction of pain, edema and other discomforts after the surgical intervention. MATERIALS AND METHODS: The methodology adopted consisted of carrying out a systematic review of the literature, following the model outlined by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The inclusion criteria were previously established according to a systematic review protocol approved by the Prospective Register of Systematic Reviews (PROSPERO) under number CRD42023484679. In order to carry out a comprehensive search, a search in five databases was carried out, PubMed, Web of Science, Scopus, Cochrane Library and Embase. RESULTS: The search resulted in the selection of randomized controlled trials that conformed to the established criteria. Two authors independently screened the records and extracted the data. The assessment of bias was conducted according to the guidelines recommended by the Cochrane Collaboration, using version 2 of the Cochrane tool for assessing the risk of bias in randomized trials (RoB 2). CONCLUSION: This study demonstrated that L-PRF stands out by providing direct benefits to healing, vascularization and tissue regeneration. CLINICAL RELEVANCE: L-PRF plays an important role in reducing postoperative pain, edema, the incidence of alveolar osteitis and infections after third molar removal surgery, compared to patients who did not undergo the use of L-PRF.

[Genistein loaded by PRF improved bone healing in obese mice].

PURPOSE: To clarify the effect of genistein(GEN) on osteogenic differentiation and explore the effect of GEN loaded by platelet-rich fibrin (PRF) on the repair process of bone defects in obese mice. METHODS: In in vitro experiments, the effect of GEN(0, 0.1, 1, 10, 50 µmol/L) on the proliferation of mouse embryonic osteoblast precursor cells (MC3T3-E1) was determined by CCK 8. Alkaline phosphatase(ALP) staining and quantitative detection of ALP activity were performed to determine the changes of ALP activity in cells; RNA and protein expression levels of ALP, osteopontin (OPN) and osteocalcin (OCN) were detected by quantitative real-time PCR(qRT-PCR) and Western blot. Alizarin red staining was used to define the effect of GEN on mineralization of MC3T3-E1. To verify the feasibility of the PRF drug loading, the ultrastructure of PRF was subsequently observed under SEM. In in vivo experiments, obese C57 mouse models were established by high-fat diet feeding. On this basis, skull defect models with a diameter of 2.8 mm were established, and the prepared GEN/PRF complexes were placed into the bone defect area. The effects of GEN on skull defect repair in obese mice were evaluated by Micro-CT scanning and hematoxylin-eosin(H-E) staining. Statistical analysis was performed with GraphPad Prism 5.0 software package. RESULTS: CCK 8 results showed that 0.1, 1 µmol/L GEN promoted cell proliferation within 7 days(P＜0.05); 10 µmol/L GEN had no significant effect on the process of cell proliferation. From the second day, 50 µmol/L GEN significantly inhibited cell growth and showed cytotoxicity(P＜0.05). These two concentrations had similar effects in promoting cellular osteogenic differentiation. SEM results showed that PRF presented a 3-dimensional network structure, providing space for loading drug molecules. In in vivo experiments, the body weight of mice in the high-fat diet (HFD) group was 27.7% greater than that in the normal diet group(P＜0.05) and had abnormal glucose tolerance (P＜0.05). Micro-CT showed that compared with the normal diet group, the number of bone trabeculae in the femur of obese mice was decreased(P＜0.05), the distance between bone trabeculae was widened(P＜0.05), and the bone density was decreased (P＜0.05). In addition, GEN (0.1, 1.0 µmol/L) loaded by PRF increased bone volume fraction in the skull of obese mice (P＜0.05). H-E results showed that GEN/PRF promoted the healing of the bone defects. CONCLUSIONS: GEN promotes osteogenic differentiation of MC3T3-E1, and it can effectively accelerate the healing of cranial bone defects after loading with PRF in obese mice.

Leukocytes within Autologous Blood Concentrates Have No Impact on the Growth and Proliferation of Human Primary Osteoblasts: An In Vitro Study.

Platelet-rich fibrin (PRF) is a widely used autologous blood concentrate in regenerative medicine. This study aimed to characterize the cellular composition and distribution of different PRF matrices generated by high (710 g) and low (44 g) relative centrifugal forces (RCFs) and to analyze their bioactivity on human primary osteoblasts (pOBs). PRF was separated into upper layer (UL) and buffy coat (BC) fractions, and their cellular contents were assessed using histological and immunohistochemical staining. The release of platelet-derived growth factor (PDGF) and transforming growth factor (TGF-ß) was quantified using an ELISA. Indirect PRF treatment on pOBs was performed to evaluate cell viability and morphology. A histological analysis revealed higher quantities of leukocytes and platelets in the low-RCF PRF. TGF-ß release was significantly higher in the low-RCF PRF compared to the high-RCF PRF. All PRF fractions promoted pOB proliferation regardless of the centrifugation protocol used. The low-RCF PRF showed higher TGF-ß levels than the high-RCF PRF. These findings contribute to understanding the cellular mechanisms of PRF and provide insights into optimizing PRF protocols for bone regeneration, advancing regenerative medicine, and improving patient outcomes.

Ultrasonographic analysis of palatal donor site healing accelerated with platelet-rich fibrin following subepithelial connective tissue harvesting.

OBJECTIVE: Platelet-rich fibrin (PRF) contains a variety of growth factors and bioactive molecules that play crucial roles in wound healing and angiogenesis. We aimed to evaluate the effects of PRF on tissue thickness and vascularization of the palatal donor site by ultrasound (USG) following subepithelial connective tissue harvesting. METHODOLOGY: A subepithelial connective tissue graft was harvested from the palatal region with a single incision for root coverage in 20 systemically healthy patients. In the test group (n = 10), the PRF membrane was placed at the donor site, whereas no material was applied in the control group (n=10). Palatal tissue thickness (PTT) and pulsatility index (PI) were evaluated by USG at baseline and on the 3rd, 7th, 14th, 30th, and 90th days after surgery. The early healing index (EHI) was used to evaluate donor site healing for 30 days. RESULTS: PTT was significantly higher in the PRF group on the 3rd and 14th days after surgery when compared to the controls. In the PRF-treated group, PI levels were significantly higher than in the controls, especially on the 14th day. PTT increased significantly 90 days after surgery compared to the test group baseline, but controls showed a significant decrease. The PRF group showed statistically significant improvements in EHI scores compared to controls on days 3, 7, and 14. This study found a negative correlation between PI values and EHI scores on postoperative days three and seven in the test group. CONCLUSION: USG is a non-invasive, objective method to radiographically evaluate the regenerative effects of PRF on palatal wound healing after soft tissue harvesting. To overcome graft inadequacy in reharvesting procedures, PRF application may enhance clinical success and reduce possible complications by increasing tissue thickness and revascularization in the donor area.