Platelet-rich fibrin modulates the expression of extracellular signal-regulated protein kinase and osteoprotegerin in human osteoblasts

Platelet-rich fibrin as an autologous biomaterial for bone regeneration: mechanisms, applications, optimization

Platelet-rich fibrin, a classical autologous-derived bioactive material, consists of a fibrin scaffold and its internal loading of growth factors, platelets, and leukocytes, with the gradual degradation of the fibrin scaffold and the slow release of physiological doses of growth factors. PRF promotes vascular regeneration, promotes the proliferation and migration of osteoblast-related cells such as mesenchymal cells, osteoblasts, and osteoclasts while having certain immunomodulatory and anti-bacterial effects. PRF has excellent osteogenic potential and has been widely used in the field of bone tissue engineering and dentistry. However, there are still some limitations of PRF, and the improvement of its biological properties is one of the most important issues to be solved. Therefore, it is often combined with bone tissue engineering scaffolds to enhance its mechanical properties and delay its degradation. In this paper, we present a systematic review of the development of platelet-rich derivatives, the structure and biological properties of PRF, osteogenic mechanisms, applications, and optimization to broaden their clinical applications and provide guidance for their clinical translation.

Injectable platelet-rich fibrin positively regulates osteogenic differentiation of stem cells from implant hole via the ERK1/2 pathway

Bone regeneration in dentistry is a dynamic approach for treating critical size bone defects that are unlikely to self-heal. Human bone marrow stem cell (hBMSCs) therapies are being tested clinically for various disorders and have remarkable clinical advancements in bone regeneration. Injectable platelet-rich fibrin (i-PRF), which is obtained from autologous blood centrifuged at 700 rpm (60 G) for 3 min can promote osteogenic differentiation of this cell, but the mechanism remains unclear. The objectives of this study were to explore the contents of i-PRF further and investigate its effect on the cell behavior of hBMSCs and the underlying molecular mechanisms. The results showed that i-PRF contained 41 cytokines, including macrophage colony-stimulating factor (M-CSF) and β-nerve growth factor (β-NGF), which had not been reported before. The Cell Counting Kit-8 and wound healing assay showed that 10% and 20% i-PRF improved the proliferation rate and the migration capacity of hBMSCs without toxicity to cells. Besides, the expression of osteogenic markers and the capacity to form mineralized nodules of hBMSCs were promoted by 20% i-PRF. Furthermore, i-PRF activated the ERK pathway, and the ERK inhibitor attenuated its effects. In summary, i-PRF promotes hBMSCs proliferation and migration and facilitates cell osteogenesis through the ERK pathway, which has promising potential in bone regeneration.

The Effects of Injectable Platelet-Rich Fibrin and Advanced-Platelet Rich Fibrin on Gingival Fibroblast Cell Vitality, Proliferation, Differentiation

BACKGROUND

Injectable Platelet Rich Fibrin (I-PRF) and Advanced-Platelet Rich Fibrin (A-PRF) are autologous materials derived from patients' blood and employed in periodontal regenerative surgery. Although I-PRF and A-PRF have different characteristics, their biological effects on gingival tissue fibroblasts remain unclear. This research aims to compare the in vitro capacity in inducing gene expression and proliferation of human gingival fibroblasts between A-PRF and I-PRF.

METHODS

Human donors undergoing dental implant surgery were sampled for normal human gingival fibroblasts (NHGFCs), followed by preparing A-PRF and I-PRF membranes. Enzyme-linked immunosorbent assay (ELISA) kit was used to assess the release of platelet-derived growth factor-AA (PDGF-AA), transforming growth factor-beta1 (TGF- β1), and insulin growth factor-1 (IGF-1) at different periods. Cell viability and proliferation of A-PRF and I-PRF were compared using CCK-8 assay. The impacts of platelet concentration on human gingival fibroblast cells (HGFCs) were evaluated by quantifying the level or amount of phosphorylated extracellular signal-regulated protein kinase (p-ERK), and Matrix metalloproteinases (MMPs), MMP-1 and MMP-3. The effects of PRF on aged human gingival fibroblast cells were examined retrospectively.

RESULTS

Overall, A-PRF demonstrated a higher release of TGF-B1 and PDGF-AA, while I-PRF reflected higher levels of IGF-1. A significantly higher level of cell proliferation was induced by higher cell proliferation by A-PRF and I-PRF. Additionally, in comparison to I-PRF, the expression of ERK phosphorylation and MMP-1 &MMP-3 in HGFCs was demonstrated by I-PRF and A-PRF. The increase in A-PRF was time-dependent (p < 0.05).

CONCLUSION

Both I-PRF and A-PRF induced a stimulatory biological impact on the proliferation of human gingiva fibroblasts, with the latter demonstrating better capacity in facilitating the release of different growth factors. A-PRF also induced higher gene expression of p-ERK, MMP-1 &MMP-3, and the proliferation of fibroblasts.

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.

Adjunctive use of platelet-rich fibrin in surgical treatment of furcation defects: A systematic review

Periodontitis is an infectious disease characterized by the inflammatory destruction of the tooth supporting tissues. In multi-rooted teeth, this process leads to periodontal destruction within furcations creating defects demanding in terms of treatment. Regeneration of class II furcation involvement, although possible, is considered an unpredictable procedure, especially in terms of the bone fill. The interest in wound healing improvement by additional use of autologous concentrates of growth factors remains high in many fields of dentistry. Platelet-rich fibrin (PRF) is a second-generation platelet concentrate and biomaterial. PRF forms a solid fibrin matrix, which is slowly remodeled comparable to the natural blood clot. Its utilization is associated with release of growth factors and glycoproteins over a long period of time. PRF activates alkaline phosphates, which show osteoblastic activity and this activation influences the bone formation. The aim of this review of randomized controlled trials (RCTs) was to evaluate the adjunctive use of platelet-rich fibrin in surgical treatment of furcation defects.

Clinical and Radiographic Evaluation of Autologous Platelet-Rich Fibrin With or Without Demineralized Bone Matrix in the Treatment of Grade II Furcation Defects

Introduction This study aims to differentiate the employment of demineralized bone matrix (DMBM; Osseograft, Advanced Biotech Products (P) Ltd, Chennai, India) and platelet-rich fibrin (PRF) alone to a composite graft consisting of both materials in the surgical actions toward the anomalies of the human periodontal furcation imperfection. Methods In a split-mouth study, 30 patients with mandibular molars affected by the furcation were allocated without conscious choice to test (PRF + DMBM, n = 30) or control (PRF, n = 30) categories. At the starting point, three months after surgery, and six months later, the following modifiable factors were evaluated: probing pocket depth (PPD), full-mouth plaque scores, full-mouth gingival scores, radiographic defect depth, relative vertical clinical attachment level (RVCAL), and relative horizontal clinical attachment level (RHCAL). Results Results at three and six months demonstrated substantial differences between baseline values for both treatment methods in clinical and X-ray imaging appraisal. Nonetheless, the PRF/DMBM group manifests statistically significantly soaring changes observed in comparison to the PRF group. Overall, the probing depth (PD) in the test site was significantly lower than that in the control site, showing a reduction of 68% (95% CI=41%, 95%, p<0.001). Conclusion Clinical indications significantly improved with PRF and DMBM combined instead of PRF alone. On radiographs, the test group also showed higher bone fill.

Effectiveness of the platelet-rich fibrin in the control of pain associated with alveolar osteitis: a scoping review

OBJECTIVES

The aim of this scoping review was to determine the effectiveness of the platelet-rich fibrin in the control of pain associated with alveolar osteitis.

MATERIALS AND METHODS

Reporting was based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Extension for Scoping Reviews. A literature search was conducted in the PubMed and Scopus databases to identify all clinical studies on the application of platelet-rich fibrin in the control of pain caused by alveolar osteitis. Data were extracted independently by two reviewers and qualitatively described.

RESULTS

The initial search returned 81 articles, with 49 identified after duplicates removal; of these, 8 were selected according to the inclusion criteria. Three of the eight studies were randomized controlled clinical trials, and four were non-randomized clinical studies, two of which were controlled. One study was case series. In all of these studies, pain control was evaluated using the visual analog scale. Overall, the use of platelet-rich fibrin resulted effective in the control of pain determined by alveolar osteitis.

CONCLUSIONS

Within the limits of this scoping review, the application of platelet-rich fibrin in the post-extra-extraction alveolus reduced the pain associated with alveolar osteitis in almost all the included studies. Nevertheless, high-quality randomized trials with adequate sample size are warranted to draw firm conclusions.

CLINICAL RELEVANCE

Pain associated with alveolar osteitis causes discomfort to the patient and is challenging to be treated. Use of platelet-rich fibrin could be a promising clinical strategy for pain control in alveolar osteitis if its effectiveness will be confirmed by further high-quality studies.

Network meta-analysis of platelet-rich fibrin in periodontal intrabony defects

OBJECTIVES

To evaluate the effect of platelet-rich fibrin alone or in combination with different biomaterials for the treatment of periodontal intra-bony defect.

METHODS

Up to April 2022, Cochrane library, Medline, EMBASE, and Web of Science databases were searched for randomized clinical trials. The outcomes of interest were probing pocket depth reduction, clinical attachment level gain, bone gain, and bone defect depth reduction. Bayesian network meta-analysis with 95% credible intervals was calculated.

RESULTS

Thirty-eight studies with 1157 participants were included. Platelet-rich fibrin alone or platelet-rich fibrin +biomaterials showed a statistically significant difference when compared with open flap debridement (p < 0.05, low to high certainty evidence). Neither biomaterials alone nor platelet-rich fibrin +biomaterials showed a statistically significant difference when compared to platelet-rich fibrin alone (p > 0.05, very low to high certainty evidence). Platelet-rich fibrin +biomaterials showed insignificant differences as compared to biomaterials alone (p > 0.05, very low to high certainty evidence). Allograft +collagen membrane ranked the best in probing pocket depth reduction while platelet-rich fibrin +hydroxyapatite ranked the best in bone gain.

CONCLUSION

It seems that (1) platelet-rich fibrin with/without biomaterials were more effective than open flap debridement. (2) Platelet-rich fibrin alone provides a comparable effect to biomaterials alone and platelet-rich fibrin +biomaterials. (3) Platelet-rich fibrin +biomaterials provide a comparable effect to biomaterials alone. Although allograft +collagen membrane and platelet-rich fibrin +hydroxyapatite ranked the best in terms of probing pocket depth reduction and bone gain respectively, the difference between different regenerative therapies remains insignificant, and therefore, further studies are still needed to confirm these results.

Comparative analysis of the effect of 4MATRIX with and without PRF on regeneration of infrabony periodontal pockets

Aim

The aim was to compare the effect in improvement of periodontal pocket depth (PPD) and clinical attachment level (CAL) between application of 4MATRIX and 4 MATRIX combined with PRF in advanced periodontal disease during follow-up of 6, 12 and 18 months.

Methods

Thirty patients of both genders aged 25-50 years were included. The patients were clinically and radiologically diagnosed with generalized advanced chronic periodontitis with the presence of periodontal pockets with a depth of ≥ 5 mm bilaterally in the upper jaw. Both sides were treated with a flap intervention in all patients. On one side a bone substitute 4MATRIX was applied, and the other side was treated with an application 4MATRIX and PRF. The clinical assessment and measurements were performed in four stages, immediately before the intervention, and then 6, 12 and 18 months after the intervention. PPD and CAL were determined in all four timepoints.

Results

PPD was the highest at zero time before the surgery for both groups and was 5.56 ± 0.28 mm. In the postoperative follow-up period, the PPD value decreased gradually with the lowest average value of 5.10 ± 0.18 mm after 18 months in Group I and 4.67 ± 0.13 mm in Group II (p < 0.001, respectively). Moreover, comparing the values of PPD at 6, 12 and 18 months after the surgery, a significant difference was found between the patients from the 4MATRIX vs 4MATRIX + PRF (p < 0.001 respectively). The postoperative follow-up period showed a decrease in CAL value with the lowest value after 18 months. A significant difference in CAL was found between the four measurement times (p < 0.001, respectively). The average level of CAL was the highest before surgical treatment in both groups. The intergroup analysis of CAL after 18 months in group I (4MATRIX) was 5.27 ± 0.17 mm and in group II 4.10 ± 0.14 mm (p < 0.001).

Conclusion

Treatment of adult patients with advanced chronic periodontitis with periodontal pockets of ≥ 5 mm bilaterally in the upper jaw using 4MATRIX and 4MATRIX + PRF showed improvement of PPD and lower CAL loss after 18 months of the treatment. In the group treated with 4MATRIX + PRF patients showed the highest improvement in PPD and CAL loss. The analysis of treatment with 4MATRIX and 4MATRIX + PRF showed the lowest values after 18 months of the treatment.

Quantitative assessment of platelet rich fibrin for the repair of extraction socket in a rat model

The present study evaluated the quantitative effects of platelet-rich fibrin (PRF) for the repair of extraction socket in Sprague Dawley (SD) rat model by assessing several key clinical parameters. Seventy two male SD rats were subjected to surgical extraction of the maxillary right incisor. Rats were randomly divided into four groups with eighteen rats in each group based on the treatment received: extraction socket without treatment of PRF was taken as control (group I). Extraction socket implanted with 0.1, 0.2, and 0.4 mL of PRF was taken as study groups (groups II, III, and IV). The obtained results demonstrated that, low dose of PRF efficiently enhanced the natural healing cascade. Whereas, high dose interfered with native tissue contribution and altered the natural healing process. The beneficial effects of quantity-based application of PRF may raise the possibility of a new approach as complementary therapy besides conventional treatment.

Nonsurgical Management of Strip Perforation Using Platelet-Rich Fibrin and MTA by Matrix Concept - A Case Report with One Year Follow-up

Iatrogenic errors happen especially during endodontic treatment even with the experienced clinicians. It is impossible to predict the occurrence of an event. Although many of them can be corrected and managed successfully, few conditions might have the worst prognosis leading to uneventful extraction. The present case report highlights a 1-year follow-up of managed strip perforation in mesial canals of mandibular first molar, nonsurgically using MTA obturation. The present challenging case gives an insight on the importance of regenerative capacity and osteogenic potentiality of bioactive materials, when appropriate tissue engineering concepts are applied.

Mineralized Plasmatic Matrix for Horizontal Ridge Augmentation in Anterior Maxilla with and without a Covering Collagen Membrane

Background:

Mineralized Plasmatic Matrix [MPM] is a unique form of platelet rich fibrin that contains mineralized bone graft particles within a fibrin network.

Aim:

This study was conducted to evaluate horizontal ridge augmentation using MPM with and without a coverage membrane.

Materials and Methods:

Sixteen edentulous spaces were randomly divided into 2 equal groups. MPM was used for horizontal ridge augmentation with and without a covering collagen membrane (group 1 and 2, respectively). Cone Beam CT images were obtained preoperatively as well as 1 week and 4 months postoperatively to evaluate alveolar ridge and the resorption of the grafting material at 3 predetermined points along with the site where the future dental implant will be placed.

Student’s t-test (Unpaired) was used for comparing two different groups with quantitative parametric data and student’s t-test (Paired) was used for comparing two related groups with quantitative parametric data while repeated measures ANOVA (Analysis of variance) followed by post-hoc Bonferroni was used for comparing more than two related groups with quantitative parametric data.

Student’s t-test (Unpaired) was used for comparing two different groups with quantitative parametric data and student’s t-test (Paired) was used for comparing two related groups with quantitative parametric data while repeated measures ANOVA (Analysis of variance) followed by post-hoc Bonferroni was used for comparing more than two related groups with quantitative parametric data.

Results:

There was no statistically significant difference between the gained bone width in both groups. More but not statistically significant resorption was recorded in group 2.

Conclusion:

MPM can be successfully used for horizontal ridge augmentation without a barrier membrane.

Effect of Carbonate Apatite Hydrogel-Advanced Platelet-Rich Fibrin Injection on Osteoblastogenesis during Orthodontic Relapse in Rabbits

Objective  This study aimed to determine the effect of carbonate apatite (CHA) hydrogel-aPRF on osteoblastogenesis during relapse in rabbits.

Materials and Methods  Forty-five rabbits were divided into three groups ( n = 15): the control, CHA, and CHA-autologous platelet-rich fibrin (aPRF) groups. An open-coil spring was compressed between brackets to distalize the lower incisors of the rabbits by delivering a force of 50 cN for 1 week. The new position of the teeth was retained for 14 days, and CHA hydrogel-aPRF was injected every 7 days. The appliances were then debonded to allow relapse. On days 0, 3, 7, 14, and 21 after debonding, transforming growth factor (TGF)-β1 and bone morphogenetic protein (BMP)-2 expression was examined using immunohistochemistry staining and Runx-2 levels were analyzed by enzyme-linked immunosorbent assay. The data collected were analyzed using analysis of variance and a post hoc Tukey’s test ( p < 0.05).

Results  Histomorphometric analysis revealed that TGF-β1 expression in the CHA-aPRF group is statistically higher than that in other groups on days 0, 3, and 7 after debonding ( p < 0.05). BMP-2 expression in the CHA-aPRF group was also statistically higher than that in the other groups on days 3, 14, and 21 after debonding ( p < 0.05). ELISA showed that Runx-2 levels are slightly higher in the CHA-aPRF group than in the other groups ( p > 0.05).

Conclusion  Although injection of CHA-aPRF aids in osteoblastogenesis associated with enhancing TGF-β1 and BMP-2 expressions, it does not significantly upregulate Runx-2 levels.

Platelet rich fibrin versus ozone gel for periodontal regeneration in induced rats' intrabony three-wall periodontal defects

BACKGROUND

The question of whether platelet rich fibrin and ozone can enhance regeneration of periodontal defect was addressed.

MATERIALS AND METHODS

three-wall periodontal defects were surgically created in 30 rats involving mesial aspect of right mandibular first molar. Rats were randomly assigned into three groups: 1) Group I (Positive control group). 2) Group II (Ozone treated group) and 3) Group III (PRF treated group). Two weeks after surgery, five rats from each group were euthanized and the remaining was euthanized 4 weeks post surgery. The degree of periodontal regeneration was evaluated using light microscope and scanning electron microscope. Histomorphometric measurements and anti-PCNA immunohistochemical counting were statistically analyzed.

RESULTS

group I showed intense inflammatory reaction with mild new bone formation. In group II, partial regeneration was seen with moderate new woven bone formation in 2 weeks period. After 4 weeks, almost complete restoration of periodontium was seen. In group III, after 2 weeks, moderate lamellar bone formation was observed. In 4 weeks period, the periodontal regeneration was almost completed. Histomorphometric analysis showed a significant difference between group I and group II. The difference between group I and group III was significant in 2 weeks and highly significant after 4 weeks. That between group II and group III was nonsignificant in 2 weeks and significant in 4 weeks. Anti-PCNA analysis was nonsignificant between groups.

CONCLUSIONS

both Platelet rich fibrin and ozone can improve histological parameters associated with healing of experimental intrabony periodontal defects in rats with the former being superior.

Evaluation of titanium-prepared platelet-rich fibrin and leucocyte platelet-rich fibrin in the treatment of intra-bony defects: A randomized clinical trial

Background. Various treatment modalities, such as leucocyte platelet-rich fibrin (L-PRF), bone grafts, and membranes, have been used for the restoration of lost periodontal tissues. Titanium-prepared platelet-rich fibrin (T-PRF) has attracted attention for its proper haemocompatibility, thick fibrin meshwork, and long resorption time. The present study aimed to evaluate the effectiveness of T-PRF and L-PRF in the management of intra-bony defects based on clinical and radiographic criteria. Methods. Twenty-six subjects with 34 intra-bony 3- walled defects were divided into two groups (n=17) and treated with T-PRF or L-PRF. Clinical and radiographic measurements were recorded at baseline and 6- , 3- and 9- month intervals and tabulated on Microsoft Excel spreadsheets. For intra- and intergroup comparisons, paired and unpaired t-tests were performed. P<0.05 was set as statistically significant Results. Intra-group comparisons revealed statistically significant differences (P<0.05) from baseline in both groups regarding clinical measurements. On intergroup comparison, the T-PRF group exhibited a significantly higher defect fill compared to the L-PRF group (P<0.05). Conclusion. Within the limits of the present study, T-PRF seems to be a better alternative to L-PRF in the treatment of intra-bony defects.

Comparative assessment of periodontal regeneration in periodontal intraosseous defects treated with PepGen P-15 unaided or in blend with platelet-rich fibrin: A clinical and high-resolution computed tomography scan-assisted volumetric analysis

Background:

PepGen P-15, a xenograft, has proven its periodontal regenerative potential. Platelet-rich fibrin (PRF) is an autologous platelet concentrate which too contributes to periodontal redevelopment through the release of different polypeptide progression factors. The present study intended to evaluate the regenerative potential of PepGen P-15 xenograft when used unaccompanied or in blend with PRF in periodontal intraosseous defects in humans through clinical and a novel computed tomography (CT) scan analysis technique.

Materials and Methods:

Twelve chronic periodontitis individuals with paired periodontal intraosseous defects were randomly treated either with PepGen P-15 exclusively (Control/Group A) or in concoction with PRF (Test/Group B) utilizing split-mouth study design. Pocket probing depth (PPD), relative attachment level (RAL), and relative position of gingival margin were assessed at 3- and 6-month interval, whereas the linear and volumetric bone defect regeneration were assessed at 6 months postoperatively using CT scan.

Results:

Both the groups validated statistically significant PPD reduction, RAL gain at 3 and 6 months, but on intergroup comparison, test group CT images revealed significantly greater linear bone gain and volumetric bone gain, with mean difference of 0.73 ± 0.28 (P = 0.018) and 2.70 ± 1.36 (P = 0.06) at 6 months in comparison to the baseline data.

Conclusions:

PepGen P-15 and PRF blend had better regeneration potential for the management of intrabony defects. Further long-term investigations on large sample size are recommended to authenticate the same.

Platelet-rich fibrin in combination with decalcified freeze-dried bone allograft for the management of mandibular degree II furcation defect: A randomised controlled clinical trial

Background: Treatment of furcation involvement of molars with periodontal disease remains challenging and unpredictable. Platelet-rich fibrin (PRF) has received the attention of researchers due to its pleiotropic properties essential for periodontal wound healing. The osteoinductive property of demineralized freeze-dried bone allograft (DFDBA) has been successfully used in periodontal regeneration. Aim: The present study aimed to explore the effectiveness of PRF alone and with DFDBA in the treatment of mandibular degree II furcation defects in subjects with chronic periodontitis. Material and Methods: Patients treated were from the Department of Periodontology and Implantology, Institute of Dental Sciences, Bareilly. A total of 60 mandibular molars were treated with either open flap debridement (OFD) alone, [Formula: see text] combination or [Formula: see text] combination. The soft and hard tissue parameters such as vertical probing depth (VPD), vertical clinical attachment level (VCAL), gingival marginal level (GML), horizontal probing depth (HPD), vertical bone fill (VBF), horizontal bone fill (HBF) and furcation width (FW) were determined at baseline and 9 months postoperatively. A paired [Formula: see text]-test was conducted to assess the statistical significance between time period within each group for clinical and radiographic parameters. ANOVA and post-hoc Tukey's tests were also conducted for intergroup comparison of soft and hard tissue parameters. Statistical significance was set at [Formula: see text]. Results and Discussion: After 9 months, all treatment groups showed significant ([Formula: see text]) improvement in soft and hard tissue parameters, except GML in all the three groups and HBF and FW in the OFD group as compared to baseline. The mean VBF change was highest in the [Formula: see text] group ([Formula: see text]) mm, followed by that in the [Formula: see text] and OFD groups ([Formula: see text] and [Formula: see text][Formula: see text]mm, respectively). Conclusions: It was shown that both [Formula: see text] and [Formula: see text] combinations were significantly advantageous for the management of mandibular degree II furcation defects. However, the [Formula: see text] combination has significantly greater benefits than [Formula: see text] combination in terms of VBF.

Effect of platelet-rich fibrin on cell proliferation, migration, differentiation, inflammation, and osteoclastogenesis: a systematic review of in vitro studies

Objective

To systematically assess the effects of platelet-rich fibrin (PRF) on in vitro cellular behavior.

Methods

A systematic electronic search using MEDLINE database was performed. In vitro studies using PRF were considered and articles published up to June 31, 2018 were screened. Eligible studies were selected based on the use of human PRF.

Results

In total, 1746 titles were identified with the search terms, from these 37 met the inclusion criteria and were chosen for data extraction. In addition, 16 new studies, mainly published in 2019, were also included in the analysis resulting in 53 studies. No meta-analysis could be performed due to the heterogeneity of study designs. Included studies show that PRF enhances proliferation, migration, adhesion, and osteogenic differentiation on a variety of cell types along with cell signaling activation. Furthermore, PRF reduces inflammation, suppresses osteoclastogenesis, and increases the expression of various growth factors in mesenchymal cells.

Summary and conclusions

Despite some notable differences of the studies, the overall findings suggest a positive effect of PRF on cell proliferation, migration, adhesion, differentiation, and inflammation pointing towards a therapeutic potential in regenerative dentistry.

Clinical relevance

PRF serves as a reservoir of bioactive molecules to support wound healing and bone regeneration. Although the cellular mechanisms by which PRF supports the clinical outcomes remain unclear, in vitro research provides possible explanations. This systematic review aims to provide an update of the existing research on how PRF affects basic physiological processes in vitro. The overall findings suggest that PRF induces cell proliferation, migration, adhesion, and differentiation along with possessing anti-inflammatory properties further supporting its therapeutic potential in wound healing and bone regeneration.

Positive impact of Platelet-rich plasma and Platelet-rich fibrin on viability, migration and proliferation of osteoblasts and fibroblasts treated with zoledronic acid

Bisphosphonates are frequently used for the antiresorptive treatment in bone metastasis diseases or for osteoporosis. A side effect of this therapy is osteonecrosis of the jaw. This inhibits osteoclast function, but osteoblasts and fibroblasts are also negatively affected in terms of impaired proliferation. Additive local treatment with platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) promotes adhesion, proliferation and migration of cells due to high concentrations of growth factors like PDGF, TGF and IGF. The aim of the study was to investigate the effect of PRP or PRF on proliferation, migration and viability of osteoblasts and oral fibroblasts, treated with zoledronic acid (ZA). ZA treated fibroblasts and osteoblasts were exposed to PRP/PRF. Cell proliferation, migration and viability were measured using the real-time cell-analyzer assay (RTCA), the scratch assay and the MTT assay. There was a significant increase in closure of the scratch area by PRP/PRF treated osteoblasts (PRP = 40.6%, PRF = 100.0%, NC = 0.0%) as well as fibroblasts (PRP = 100.0%, PRF = 100.0%, NC = 12.7%) in comparison to the group of negative control (all p ≤ 0.05). Furthermore, the negative effect of ZA on cell migration was generally reduced in both cell lines using PRP/PRF. The viability and proliferation of cells decreased after exposure to ZA, whereas we observed an enhancement of cell viability within 24 hours by application of PRP/PRF in ZA treated cells. The negative effect of ZA on cell proliferation was especially reduced when using PRF. The use of PRF/PRP improves the behavior of ZA-treated cells, but PRF appears to have an advantage in comparison to PRP. This study demonstrates that treatment with PRF/PRP may have positive effects in the therapy of Bisphosphonate-Related Osteonecrosis of the Jaw (BRONJ).

Platelet-rich fibrin increases the osteoprotegerin/receptor activator of nuclear factor-κB ligand ratio in osteoblasts

Platelet-rich fibrin (PRF) is a platelet concentrate derived from complete autologous blood rich in growth factors in the fibrin matrix. Although PRF has been used during oral surgery to optimize wound healing in soft and hard tissue, the precise role of PRF in bone healing remains unclear. The present study assessed the role of PRF in bone remodeling. PRF was prepared from whole blood by low speed centrifugation without any anti-coagulants. Culture of MC3T3-E1 cells with PRF induced the expression of osteoprotegerin (OPG), but had no effect on the expression of receptor activator of nuclear factor-κB ligand (RANKL), increasing the OPG/RANKL ratio. Expression of other osteoblastic differentiation makers, including BMP-2 and −4 and RUNX2, was not affected. PRF filling of a hole defect in the mental foramen bone of rats increased OPG positivity and decreased tartrate-resistant acid phosphatase positivity compared with unfilled control. In conclusion, PRF increased the OPG/RANKL ratio by inducing OPG expression, suggesting that PRF enhances early stage osteogenesis by optimizing osteoblastic differentiation. The present study provides a scientific basis for clinical findings showing that PRF can enhance bone regeneration such as sinus lift.

Study of platelet-rich fibrin combined with rat periodontal ligament stem cells in periodontal tissue regeneration

The objective of this study was to investigate the advantages and feasibility of periodontal tissue regeneration using platelet‐rich fibrin (PRF) combined with rat periodontal ligament stem cells (PDLSCs) for the first time. We first determined the effect of PRF on rat PDLSCs in vitro. We next conducted an in vivo study, in which a tissue engineering technique was performed to repair periodontal defects in five groups: a blank group, collagen group (implanted collagen membrane), collagen + cells group (implanted collagen membrane and rat PDLSCs), PRF group (implanted PRF membrane) and PRF + cells group (implanted PRF membrane and rat PDLSCs). PRF greatly enhanced cell proliferation, mRNA and protein expression levels of bone sialoprotein (BSP), osteocalcin (OC), and runt‐related transcription factor 2 (RUNX2) and activity of alkaline phosphatase (ALP) in vitro. Transplantation of PRF combined with rat PDLSCs resulted in higher expression of osteopontin (Opn), collagen I (COL1A) and RUNX2 at both 12 and 24 days after surgery. Micro‐computed tomography and histological analysis showed substantially more new bone formation in the PRF + cells group at 24 days after surgery. Based on these results, we discuss the role of PRF in the proliferation and differentiation of rat PDLSCs and suggest that PRF combined with rat PDLSCs provides a valuable tool for periodontal tissue engineering.

Evaluation of L-PRF combined with deproteinized bovine bone mineral for early implant placement after maxillary sinus augmentation: A randomized clinical trial

PURPOSE

To investigate the effectiveness of adding leukocyte and platelet-rich fibrin (L-PRF) to deproteinized bovine bone mineral (DBBM) for early implant placement after maxillary sinus augmentation.

MATERIALS AND METHODS

Twelve patients requiring two-stage bilateral maxillary sinus augmentation were enrolled to the study. The elevated sinus cavities were randomly grafted with DBBM + L-PRF (test) or DBBM alone (control) in a split-mouth design. Implants were placed in the augmented sites after 4 months in the test group and 8 months in the control group. Bone biopsies were collected during implant placement for histomorphometric evaluation. Resonance frequency analysis was performed immediately after implant placement and at implant loading in both groups. Cone-beam computed tomography was obtained preoperatively and postoperatively for evaluation of graft volume changes.

RESULTS

Both procedures were effective for maxillary sinus augmentation. Cone-beam computed tomography analysis did not reveal differences in graft volume between test and control group at any of the evaluated time points (P > .05). Histological evaluation demonstrated increased percentage of newly formed bone for the test group (44.58% ± 13.9%) compared to the control group (30.02% ± 8.42%; P = .0087). The amount of residual graft in the control group was significantly higher (13.75% ± 9.99%) than in the test group (3.59 ± 4.22; P = .0111). Implant stability quotient (ISQ) immediately after implant placement was significantly higher in the control group (75.13 ± 5.69) compared to the test group (60.9 ± 9.35; P = .0003). The ISQ values at loading did not differ between the groups (P = .8587). Implant survival rate was 100% for both groups.

CONCLUSION

The addition of L-PRF to the DBBM into the maxillary sinus allowed early implant placement (4 months) with increased new bone formation than DBBM alone after 8 months of healing.

The Combined Effect of Bioactive Glass and Platelet-Rich Fibrin in Treating Human Periodontal Intrabony Defects - A Clinicoradiographic Study

Background:

Platelets are richest source for cytokine and growth factors which are two important components for the re-establishment of bone and maturation of the soft tissue.

Aims and Objective:

The additive effect of PRF along with a synthetic bone graft material in treating human intrabony periodontal defects has been evaluated in this study. The appropriate use of platelet-rich fibrin (PRF) as an alternate comfortable graft material to restore the lost periodontal tissues has been well documented and has given clinically promising outcome.

Materials and Method:

Platelet-rich fibrin (PRF) is prepared from patient's own blood which is autologous in nature. Perio Glas (PG) is an easy to use synthetic absorbable osteostimulative as well as osteoconductive bone graft material. The selected 30 sites were randomly divided into two groups such as Test (15 sites using PRF) and Control (15 sites without PRF).

Results:

At the end of Six months, the post-operative evaluations revealed significant reduction in PPD and gain in CAL. Radiographic evidence of bone formation was also noticed. The incorporation of PRF with synthetic bone graft (perioglas) produces effective and rapid periodontal regeneration with improved healing in intrabony osseous defects. The PRF group showed a mean Radiographic Defect Fill (RDL) of 1.24 ± 0.04 compared with 0.79 ± 0.07 of control group which is statistically significant.

Conclusion:

This combination technique can be used as an alternate grafting modality for the treatment of intrabony periodontal defects with satisfactory clinical consequences.

Comparative study using autologous platelet-rich fibrin and titanium prepared platelet-rich fibrin in the treatment of infrabony defects: An in vitro and in vivo study

Background:

The platelet concentrates had been pioneered to be used in regenerative medicine since above a decade.

Aims and Objectives:

To compare the autologous platelet rich fibrin (PRF) and titanium prepared platelet rich fibrin (T-PRF) in the treatment of infrabony defects, clinically and radiographically and to compare the histologic difference between PRF and T-PRF by light microscopy and scanning electron microscopy (SEM).

Materials and Methods:

The present study is a split mouth randomised controlled trial study in which 20 sites were selected and randomly assigned equally into 10 sites each in group A [Test group=T-PRF] and group B [Control group=PRF]. Clinical parameters were evaluated at baseline,3 months and 9 months. Radiographic parameters were evaluated at baseline and 9 months. Histologic differences between light microscopy and SEM for both PRF and T-PRF was studied after sequential processing.

Results:

There was marked reduction in Probing Pocket depth and gain in Clinical Attachment Level in both the T-PRF and PRF groups from baseline to 9 months in intragroup comparisons. However, on intergroup comparisons, no statistical significance was seen. Radiographically, mean defect depths for both the groups showed statistically significant reduction from baseline values to 9 months on intragroup comparisons but not on intergroup comparisons. In-vitro evaluation, on both light and scanning electron microscopy, T-PRF showed denser fibril meshwork as compared to PRF.

Conclusion:

The clinical parameters and radiographic outcomes showed marked improvement at 9 months with both PRF and T-PRF in the treatment of infrabony defects from baseline values in intragroup comparison. However, statistically efficacy of T-PRF was not seen to be superior to that of PRF both clinically and radiographically. Histologic evaluation showed T-PRF had denser fibrils as compared to PRF in both light and scanning electron microscopy.

Clinical and radiographic evaluation and comparison of bioactive bone alloplast morsels when used alone and in combination with platelet-rich fibrin in the treatment of periodontal intrabony defects-A randomized controlled trial

BACKGROUND

The present study aims to evaluate and compare the clinical and radiographic changes obtained through Bioactive Glass (BG) with and without autologous platelet-rich fibrin (PRF) in the treatment of intrabony defects in chronic periodontitis patients.

METHODS

The present study was a split-mouth randomized controlled clinical trial comprising 20 chronic periodontitis patients (mean age: 35.9 years) having at least one pair of bilateral intrabony defect. Group 1 included 20 sites treated with a combination of BG and autologous PRF whereas 20 sites in Group 2 were treated with BG alone. Probing pocket depth (PPD), clinical attachment level (CAL) and gingival recession (GR) were evaluated at 3 and 6 months and bone fill at 6 months by using cone beam computed tomography (CBCT) analysis. Primary study outcomes were changes in PPD, CAL, GR, and bone fill.

RESULTS

CAL gain was greater in Group 1 (5.05 ± 1.09 mm) when compared with Group 2 (4.2 ± 1.70 mm). Furthermore, a significantly greater bone fill was found in Group 1. At 6 months, statistically significant reduction in PPD in Group 1 and Group 2 was evident.

CONCLUSION

BG morsel when used in combination with PRF is found to be more effective in gain in CAL, reduction in PPD and achieving greater bone fill as compared with treatment with BG alone in periodontal intrabony defects and is indicative of enhanced periodontal regeneration.

The sole and combined effect of simvastatin and platelet rich fibrin as a filling material in induced bone defect in tibia of albino rats

Statins like simvastatin (SIM) have demonstrated to have pleiotropic actions other than their conventional use as antilipidemic drugs. Also, nowadays natural scaffolds like platelets rich fibrin (PRF) showed promising results on bone regeneration. Aim This study compare the regenerative power of SIM and PRF added locally each as a sole filling material on induced bone defect and evaluate the combined effect using PRF loaded with SIM. MATERIALS AND METHODS: A critical size bone defect was induced in 48 male albino rats of average weight 150-200 g and were divided into 4 groups according to the filling material. Control, PRF, SIM, and SIM/PRF group. Each group was subdivided according to the sacrificing period into two subgroups (one and two-months postoperatively). Tibial specimens were evaluated histologically using masson trichrome (MT) special stain to detect areas of new bone formation, immunohistochemically using anti- BMP2 and anti-VEGF, serum levels of Osteoprotegerin (OPG), RANKL, osteocalcin and alkaline phosphatase enzyme (ALP) were measured one and two months postoperatively using ELISA, Finally bone mineral density (BMD) at the bone defect area was analyzed using digital X-ray one and two-months postoperatively. RESULTS: The percentage of newly formed bone increased significantly in the three groups vs the control group with the highest significant increase (p < 0.001) in the SIM/PRF group one month postoperatively. Also, SIM/PRF group was the only group which showed significant bone maturation two-months postoperatively compared to the other groups. Immunohistochemical analysis showed significant increase in positively stained BMP-2 and VEGF expression (p < 0.001) in the three groups vs the control group with the highest significant increase (p < 0.001) in the SIM/PRF group. Serum bone anabolic markers increased significantly in the SIM and SIM/PRF groups. In contrast, RANKL serum level decreased significantly in the SIM and SIM/PRF group one month postoperatively with no significant decrease in the PRF group vs the control group. Digital X-ray results revealed the highest BMD percent change was found in the SIM/PRF group and showed complete bone healing two-months postoperatively.

Bone regeneration around immediate placed implant of molar teeth with autologous platelet-rich fibrin: Two case reports

RATIONALE

There are some challenges concerning immediate implant placement in molar region. Platelet-rich fibrin (PRF), a second generation platelet concentrate, is an autologous fibrin matrix and contains platelets, growth factors, and leukocytes. It is used for tissue healing and regeneration in periodontal and oral-maxillofacial surgery. We report 2 cases of immediate placed implant of molar teeth with autologous PRF to improve and accelerate tissue healing.

PATIENT CONCERNS

Case 1 was a 38-year-old female patient with masticatory discomfort. Case 2 was a 43-year-old male patient with a demand for his left mandibular posterior tooth restoration.

DIAGNOSES

Through the clinical and radiographic examination, the patient in case 1 was diagnosed with vertical root crown fracture of the maxillary right first molar. The patient in case 2 was diagnosed with residual root of the left mandibular first molar via cone-beam computer tomography and clinical examination.

INTERVENTIONS

The 2 patients underwent extraction of the molar teeth and immediate placed implant of molar teeth with autologous PRF was performed. In case 1, the gap between the implant surface and the socket walls of freshly extracted tooth was filled with PRF mixed with a commercial spongious bone substitute, followed by 2 PRF membranes coverage for protection. In case 2, PRF was used as a sole bone substitute material, placed between immediate implant and the socket wall of freshly extracted tooth.

OUTCOMES

Follow-up of 2 cases revealed successful osseointegration and matured gingiva with optimal form and function.

LESSONS

The results suggested that PRF could solely serve as a bone scaffold in 4-wall bony defects, or can be combined with xenograft in 3-wall bony defects during immediately placed implants in molar regions, exhibiting excellent biocompatibility and good soft and hard tissue healing.

Bone alkaline phosphatase and osteocalcin expression of rat's Gingival mesenchymal stem cells cultured in platelet-rich fibrin for bone remodeling (in vitro study)

OBJECTIVE

The aim of this study was to analyze the osteogenic differentiation of rat GMSCs cultured in PRF for bone remodeling.

MATERIALS AND METHODS

GMSCs were isolated from the lower gingival tissue of four healthy, 250 g, 1-month old, male rats (Rattus norvegicus) cut into small fragments, cultured for 2 weeks, and subsequently passaged every 4-5 days. GMSCs isolated in passage 3 were characterized by CD34, CD45, CD44, CD73, CD90, and CD105 using fluorescein isothiocyanate immunocytochemistry (ICC) examination. GMSCs in passage 3-5 cultured in five M24 plates (N = 108; n = 6/group) for 7, 14, and 21 days with three different mediums as follows: Control (-) group: α-Modified Eagle Medium; Control (+) group: High-dose glucose Dulbecco's Modified Eagle's Medium (DMEM-HG) + osteogenic medium; and treatment group: DMEM-HG + osteogenic medium + PRF. GMSCs were osteogenic differentiation cultured in vitro in three different mediums by bone alkaline phosphatase (BALP) and osteocalcin (OSC) marker using ICC monoclonal antibody.

STATISTICAL ANALYSIS USED

The one-way analysis of variance was performed (P < 0.05) based on Shapiro-Wilk and Levene's tests (P > 0.05).

RESULTS

GMSCs were shown to present + CD44, +CD73, +CD90, +CD105 and - CD34, - and CD45 expression as MSCs markers. The treatment group showed the highest BALP expression (16.00 ± 1.732) on day 7, while OSC expression (13.67 ± 2.309) on day 21 showed the statistically significant difference between groups (P < 0.05).

CONCLUSION

GMSCs cultured in PRF demonstrated potential osteogenic differentiation ability capable of accelerating in vitro bone remodeling by enhancing BALP and OSC expression.

Platelet‑rich fibrin exudate promotes the proliferation and osteogenic differentiation of human periodontal ligament cells in vitro

The purpose of the present study was to evaluate the effects of platelet-rich fibrin (PRF) exudate on the proliferation, osteogenic differentiation and mineralization of human periodontal ligament cells (hPDLCs) in vitro. In the present study PRF was obtained with permission, from the peripheral blood of healthy donors and PRF exudates were collected on the 7th day of incubation. hPDLCs were obtained from healthy premolars, cultured by a tissue explant method and identified with anti-vimentin and anti-cytokeratin antibodies. PRF exudates were added to hPDLCs in different concentrations to evaluate cell proliferation and osteogenic differentiation. The proliferation of hPDLCs was measured using a colorimetric assay. Osteogenic differentiation and mineralization were determined by Alizarin red staining, alkaline phosphatase activity (ALP), western blotting and reverse transcription-quantitative polymerase chain reaction. Cell proliferation was enhanced by addition of the PRF exudate, which also promoted the formation of mineralized matrix nodules and upregulated ALP activity and osteoblast-associated levels of osteocalcin, runt-related transcription factor and osterix gene expression. As these stimulatory effects occurred in a dose-dependent manner, it was concluded that high concentrations of the PRF exudate served an essential role in the proliferation, osteogenic differentiation and mineralization of hPDLCs in vitro. The present study demonstrated that PRF exudate enhanced hPDLC proliferation, induced the osteoblastic differentiation of hPDLCs into mineralized tissue-formation cells in vitro, and may therefore provide potential benefits for periodontal tissue engineering; contributing to the primary processes of periodontal tissue regeneration. From the perspective of both economics and biology, PRF has greater clinical benefits than analogous growth factors.

Osteogenic potential of gingival stromal progenitor cells cultured in platelet rich fibrin is predicted by core-binding factor subunit-α1/Sox9 expression ratio ( in vitro)

Background: Alveolar bone defect regeneration has long been problematic in the field of dentistry. Gingival stromal progenitor cells (GSPCs) offer a promising solution for alveolar bone regeneration. In order to optimally differentiate and proliferate progenitor cells, growth factors (GFs) are required. Platelet rich fibrin (PRF) has many GFs and can be easily manufactured. Core-binding factor subunit-α1 (CBF-α1) constitutes a well-known osteogenic differentiation transcription factor in SPCs. Sox9, as a chondrogenic transcription factor, interacts and inhibits CBF-α1, but its precise role in direct in vitro osteogenesis remains unknown. GSPCs cultured in vitro in PRF to optimally stimulate osteogenic differentiation has been largely overlooked. The aim of this study was to analyze GSPCs cultured in PRF osteogenic differentiation predicted by CBF-α1/Sox9. Methods: This study used a true experimental with post-test only control group design and random sampling. GPSCs isolated from the lower gingiva of four healthy, 250-gram, 1-month old, male Wistar rats ( Rattus Novergicus) were cultured for two weeks, passaged every 4-5 days. GSPCs in passage 3-5 were cultured in five M24 plates (N=108; n=6/group) for Day 7, Day 14, and Day 21 in three different mediums (control negative group: αModified Eagle Medium; control positive group: High Glucose-Dulbecco's Modified Eagle Medium (DMEM-HG) + osteogenic medium; Treatment group: DMEM-HG + osteogenic medium + PRF). CBF-α1 and Sox9 were examined with ICC monoclonal antibody. A one-way ANOVA continued with Tukey HSD test (p<0.05) based on Kolmogorov-Smirnov and Levene's tests (p>0.05) was performed. Results: The treatment group showed the highest CBF-α1/Sox9 ratio (16.00±3.000/14.33±2.517) on Day 7, while the lowest CBF-α1/Sox9 ratio (3.33±1.528/3.67±1.155) occurred in the control negative group on Day 21, with significant difference between the groups (p<0.05). Conclusion: GSPCs cultured in PRF had potential osteogenic differentiation ability predicted by the CBF-α1/sox9 ratio.

Does Adding Silver Nanoparticles to Leukocyte- and Platelet-Rich Fibrin Improve Its Properties?

Objectives

Leucocyte- and platelet-rich fibrin (L-PRF) membrane can be used in various regenerative treatments. In the case of classical heterologous membrane exposure, microorganisms can be colonized on it and jeopardize the success of treatment. The aim of this study was to compare the antibacterial, mechanical, and histologic characteristics of the L-PRF membrane before and after the addition of silver nanoparticles (SNP).

Materials and Method

This study was performed on 10 volunteer men aged 25-35 years. 20 ml whole bloods were collected from each person and L-PRFs were made by routine and SNP modified method. Mechanical, antibacterial, and histological properties were evaluated.

Results

The antibacterial efficacy of L-PRF and nanosilver-modified L-PRF was presented as Klebsiella pneumonia had growth on the L-PRF membrane after 12 hours. After 24 hours, Klebsiella pneumonia and Streptococcus viridans had growth on L-PRF and only Klebsiella pneumonia had growth on SNP-L-PRF. The tensile strength and stiffness were significantly higher in the SNP-L-PRF. Precipitation of the SNPs was patchy in the outer layers and quite homogeneous in the inner core.

Conclusion

Modification of L-PRF with SNP improves the mechanical properties and antibacterial activity of the L-PRF. It can play an important role in regenerative procedures.

Enhancement of post-orthodontic tooth stability by carbonated hydroxyapatite-incorporated advanced platelet-rich fibrin in rabbits

OBJECTIVE

To evaluate the effect of carbonated hydroxyapatite-incorporated advanced platelet-rich fibrin on relapse and bone remodelling in rabbits.

MATERIALS AND METHODS

Forty-five rabbits were divided into 3 groups (n = 15): a control group, carbonated hydroxyapatite (CHA) and carbonated hydroxyapatite-incorporated advanced platelet-rich fibrin (CHA-aPRF) group. The lower incisors were subjected to an orthodontic force of 50 cN. During the retention period, CHA and CHA-aPRF hydrogel were gently injected in the mesial gingival sulcus every 7 days. Next, the appliances were debonded to allow relapse. At 5 subsequent time points (0, 3, 7, 14 and 21 days after debonding), the distance between the mesial tips of rabbits incisors was measured using a digital calliper, osteoblast quantity was evaluated using haematoxylin-eosin staining and osteoclast activity was examined using tartrate-resistant acid phosphatase (TRAP) staining.

RESULTS

The relapse rate of CHA-aPRF group was lower than that of the other groups, and the relapse distances were significantly lower on days 14 and 21 (P < .05). Histological analysis revealed that the number of osteoblasts was significantly higher and that the osteoclast activity was significantly lower in the CHA-aPRF group compared with the other groups (P < .05).

CONCLUSIONS

Intrasulcular injection of hydrogel CHA incorporated aPRF can locally reduce orthodontic relapse in rabbits.

Early Placement of Dental Implants in Maxillary Sinus Grafted With Leukocyte and Platelet-Rich Fibrin and Deproteinized Bovine Bone Mineral

This case report aimed to describe the effects of leukocyte and platelet-rich fibrin (L-PRF) associated with demineralized bovine bone mineral (DBBM) and absorbable collagen membrane (CM) on bone regeneration in maxillary sinus augmentation. A 59-year-old male patient was referred to the Department of Periodontology for implant rehabilitation of his edentulous upper jaw. The treatment plan involved maxillary sinus augmentation followed by implant installations. A split-mouth design was employed in which the right maxillary sinus was filled using L-PRF, DBBM, and CM; the left side was filled with DBBM and CM. After 4 and 8 months postoperatively, 2 dental implants were installed in each of the right and left maxillary sinuses. Cone-beam computerized tomography (CBCT) was taken before and after sinus augmentation for evaluation of tridimensional bone volume alterations. Bone biopsies were harvested from the implant sites for histomorphometric evaluation. Resonance frequency analysis was employed immediately after implant placement and before prosthetic rehabilitation for evaluation of implant stability. Implants were loaded 10 months after sinus augmentation. CBCT analysis showed a higher resorption rate in the right side of the maxillary sinus (L-PRF + DBBM) compared to the left side (22.25% and 8.95%, respectively). Implant stability quotients were above 68 in all time-points for both groups. Histomorphometric analysis showed a high amount of newly formed bone when L-PRF was used compared with DBBM alone (2 118 102 and 975 535 mm³, respectively). Taken together, both techniques were effective for maxillary sinus augmentation, however the addition of L-PRF to the graft allowed early implant placement and accelerated bone healing in the conditions studied.

Regenerative potential of autologous platelet-rich fibrin with and without amnion membrane in the treatment of Grade-II furcation defects: A clinicoradiographic study

Context

Platelet-rich fibrin (PRF), platelet concentrate composed of cytokines and structural glycoproteins trapped within polymerized fibrin meshwork, has the potential to accelerate healing of periodontal tissues. Amnion membrane has also attracted a lot of attention in periodontal regeneration due to the presence of variety of growth factors.

Aims

The aim of the study is to evaluate and compare the regenerative potential of autologous PRF with and without amnion membrane in the treatment of Grade II furcation defects.

Settings and Design

This was a double-masked randomized, split-mouth design study.

Materials and Methods

Fifteen patients with thirty mandibular degree II furcation defects were randomly allotted into Group I (PRF and amnion membrane) and Group II (PRF). Clinical parameters such as plaque index and gingival index-at defect site along with probing pocket depth, and relative attachment level and furcation defect depth were recorded at baseline, 3 months, and 6 months postoperatively. Assessment of radiographic parameters was done at baseline and 6 months postoperatively aided by computer-assisted tomography (Dentascan).

Statistical Analysis Used

For intragroup variations, Wilcoxon signed-rank test, and for comparison between the two groups/intergroup variations, Independent t-test and Mann-Whitney test was performed.

Results

All clinical and radiographic parameters showed statistically significant improvement at the sites treated with PRF and amnion membrane compared to those with PRF alone.

Conclusions

Within the limitation of this study, there was greater pocket reduction, attachment level gain, and bone fill at sites treated with PRF and amnion membrane as compared to PRF alone.

Maxillary sinus augmentation with leukocyte and platelet-rich fibrin and deproteinized bovine bone mineral: A split-mouth histological and histomorphometric study

OBJECTIVES

To evaluate the effect of leukocyte and platelet-rich fibrin (L-PRF) in combination with deproteinized bovine bone mineral (DBBM) on bone regeneration in maxillary sinus augmentation.

MATERIAL AND METHODS

Thirteen patients (nine males and four females, mean age ± SD; 49.92 ± 10.37) were enrolled to the study. 26 maxillary sinus augmentation procedures were randomly performed using DBBM and L-PRF mixture (test) or DBBM alone (control) in a split-mouth design. The same surgical procedures were performed in both groups, and bone biopsies were harvested from the implant sites 6 months postoperatively for histological and histomorphometric evaluations as the primary outcome of the study. Implants were placed and then loaded in the augmented sites after 6 months. The secondary outcomes included clinical and radiographic data and were obtained pre- and postoperatively.

RESULTS

There was no qualitative difference in histological analyses among the groups. In all samples, a newly formed bone was in direct contact with the residual material. The percentages of newly formed bone (test; 21.38 ± 8.78% and control; 21.25 ± 5.59%), residual bone graft (test; 25.95 ± 9.54% and control; 32.79 ± 5.89%), bone graft in contact with the newly formed bone (test; 47.33 ± 12.33% and control; 54.04 ± 8.36%), and soft tissue (test; 52.67 ± 12.53% and control; 45.96 ± 8.36%) were similar among the groups (p < .05). Similar radiographic bone height in the augmented area was observed, and implant survival rate was 100% for both groups.

CONCLUSIONS

Both techniques were effective for maxillary sinus augmentation, and after 6 months of healing, the addition of L-PRF in DBBM did not improve the amount of regenerated bone or the amount of the graft integrated into the newly formed bone under histological and histomorphometric evaluation.

Management of Dens Invaginatus Type II Associated with Immature Apex and Large Periradicular Lesion Using Platelet-rich Fibrin and Biodentine

Dens invaginatus (DI) poses peculiar challenges in endodontic treatment of teeth because of distortion of pulpal space. A case of Oehlers type II DI with open apex and large periapical lesion is reported. The case was managed using cone-beam computed tomography (CBCT), operating microscope, platelet-rich fibrin (PRF), and Biodentine. A 15-year-old male patient presented with palatal swelling. Pulp sensibility testing of right maxillary lateral incisor was negative. Intraoral periapical digital radiograph revealed an Oehlers type II DI with open apex and periapical radiolucency. A CBCT scan was performed to study the anatomy, determine the true extent of the periapical lesion, and form a treatment plan. A diagnosis of Oehlers type II DI with pulp necrosis and acute periapical abscess was made. Two-visit endodontic treatment was performed. In the first visit, the invaginated central mass was removed under operating microscope, chemo-mechanical preparation was done, and double antibiotic paste dressing was placed. In the second visit, the canal was sealed with apical matrices of PRF and Biodentine as filling material. The patient was asymptomatic and radiographs revealed continued healing of the osseous defect at follow-up visits. A CBCT scan at 30 months showed complete continuity of periodontal ligament space, healing of labial and palatal cortical plates, and formation of intercortical bone. The advances in endodontic armamentarium and technology, like CBCT and operating microscope, have made successful treatment of challenging cases possible. PRF and Biodentine as apical matrices and filling material, respectively, proved to be effective in the present case.

Adjunctive Effect of Autologus Platelet-Rich Fibrin to Barrier Membrane in the Treatment of Periodontal Intrabony Defects

BACKGROUND AND AIM

Autologous platelet-rich fibrin (PRF) and barrier membranes in the treatment of intrabony defects in chronic periodontitis patients have shown significant clinical benefits. This study evaluates the additive effect of autologous PRF in combination with a barrier membrane versus the use of barrier membrane alone for the treatment of intrabony defects in chronic periodontitis patients.

METHODS

A randomized split-mouth design was used. Sixteen patients with 32 paired intrabony defects were included. In each patient 1 defect was treated using a resorbable collagen membrane along with PRF (test group) and the other defect by guided tissue regeneration alone (control group). The following clinical parameters were measured at baseline and after 9 months: plaque index, modified sulcus bleeding index, probing pocket depth, clinical attachment level, and gingival marginal level. The radiographic defect depth was also assessed at baseline and after 9 months.

RESULTS

Test group showed a statistically significant improvement for probing depth (P = 0.002), clinical attachment level (P = 0.001), and radiographic defect depth (P < 0.001) after 9 months as compared with the control sites. Radiographic defect depth reduction was 58.19 ± 13.24% in the test group as compared with 24.86 ± 9.94% reduction in the control group.

CONCLUSIONS

The adjunctive use of PRF in combination with barrier membrane is more effective in the treatment of intrabony defects in chronic periodontitis as compared with barrier membrane alone.

Comparative evaluation of the isolation and quantification of stem cells derived from dental pulp and periodontal ligament of a permanent tooth and to assess their viability and proliferation on a platelet-rich fibrin scaffold

BACKGROUND

The present study aims to comparatively evaluate the isolation and quantification of stem cells derived from dental pulp and periodontal ligament of a permanent tooth and to assess their viability and proliferation on a platelet-rich fibrin (PRF) scaffold.

MATERIALS AND METHODS

A total of 15 systemically healthy individuals between the age group of 15-25 years requiring third molar or orthodontic premolar extractions. Teeth were extracted atraumatically and transported to the laboratory. Stem cells were isolated from dental pulp and periodontal ligament. After attaining more than 90% confluency by the 7th day, these cells were tested for their viability and characterization. Stem cells were also incubated with PRF and viability was assessed on the 7th day.

RESULTS

The mean number of cell for dental pulp stem cells (DPSCs) and periodontal ligament stem cell (PDLSC) was statistically insignificant (P > 0.05). The mean live cell viability was compared between DPSC (98.07%) and PDLSC (98%). Both DPSC and PDLSC showed a high percentage of expression of CD73 markers, 30.40% and 29.80%, respectively. However, DPSCs and PDLSCs lacked expression of CD34 expressing only 3.47% and 3.53%, respectively. PRF membrane as a scaffold exhibited no cytotoxic effects on DPCS's or PDLSC's. The cell viability of cells cultured with PRF was statistically insignificant (P > 0.05) when compared to the cells cultured with culture media.

CONCLUSION

The study thus indicates that dental pulp and periodontal ligament are both rich sources of mesenchymal stem cells and can be successfully used for obtaining stem cells. PRF exhibits no cytotoxic effects on the cells and can be used in conjunction with dental stem cells.

Positive effect of platelet rich fibrin on osseointegration

Background

Leukocyte-platelet rich fibrin (L-PRF) is a second generation platelet concentrate clinically used to accelerate tissue healing and bone regeneration. Achieving reduced implant osseointegration time could provide immediate or early loading of implants. The aim of this study was to evaluate the L-PRF-induced osseointegration and bone-implant contact (BIC) in an experimental animal model.

Material and Methods

Twelve 4-month-old New Zealand white rabbits were used. Following general anesthesia, 3-5 mL of blood was obtained from the central artery in rabbit ear and L-PRF was prepared. Two implant cavities (5 mm long and 3 mm in diameter) were created in each tibia with a total of four cavities in each animal. Two of these cavities were selected and covered with PRF (test group). The remaining L-PRF was used to soak the implants placed into the L-PRF covered sockets. Other cavities were left as controls. In total, 48 implants were placed. Animals were sacrificed after two, three, or four weeks. Histological samples were obtained and peri-implant tissues were histomorphometrically evaluated for bone-to-implant contact and new bone formation.

Results

Histomorphometric analyses of the defects revealed that the L-PRF was detectable up to the second week. Application of L-PRF increased the rate and amount of new bone formation in the experimental group compared to the control group. Bone-to-implant contact was enhanced when the surface was pre-wetted with L-PRF (p<0.01).

Conclusions

The results of this study demonstrated that L-PRF application may increases amount and rate of new bone formation during the early healing period and provides a faster osseointegration around implants.

Key words:Dental implants, platelet rich fibrin, osseointegration, bone regeneration, matrix for growth factors.

Surgical Re-entry of an Intentionally Replanted Periodontally Compromised Tooth Treated with Platelet Rich Fibrin (PRF): Hopeless to Hopeful

Intentional replantation is generally contraindicated in periodontally compromised teeth however, there are reports suggesting that it can be a successful treatment alternative for periodontally involved hopeless teeth. Currently there is dearth of evidence regarding the success of this therapy, especially evidence for the effectiveness of autologous platelet rich fibrin is lacking. We present a case report of a 23-year-old male patient with periodontally hopeless left maxillary central incisor having bone loss extending beyond root apex. The tooth was gently extracted and replanted utilizing root conditioning and combined regenerative therapy (Xenograft, PRF and Type I Collagen Membrane). Surgical re-entry at nine months revealed bone formation in the apical third of the tooth. At one year, 87% radiographic bone gain was accomplished. The improvement in the clinical and radiographic parameters reinforced by the re-entry surgery findings strongly suggest that intentional replantation may be a cost-effective substitute to implants and tooth supported prosthesis in situations where conventional periodontal therapy would yield compromised outcomes.

Evaluation of osteoblastic activity in extraction sockets treated with platelet-rich fibrin

OBJECTIVE

The aim of this study was to determine whether the use of platelet rich fibrin (PRF) improved the healing of extraction sockets.

STUDY DESIGN

A total of 20 patients with bilateral soft tissue impacted mandibular third molars were included in this study. The left and right third molars were extracted during the same session. Subsequently, the PRF membrane was randomly administered to one of the extraction sockets, whereas the contralateral sockets were left without treatment. On postoperative 30. and 90. days, panoramic images and bone scintigrams were taken to evaluate the bone healing between PRF-treated and non-PRF-treated sockets. Also, periodontal evaluation was performed in the same control sessions. Dependent group t test for paired samples was used for statistical analysis.

RESULTS

The average increase in technetium-99m methylene diphosphonate uptake as an indication of enhanced bone healing did not differ significantly between PRF-treated and non-PRF-treated sockets 30 and 90 days postoperatively. Radio-opacity that can show the bone healing on panoramic images were measured by Image J programme and they did not differ significantly. Also periodontal values did not differ significantly.

CONCLUSIONS

PRF might not lead to enhanced bone healing in impacted mandibular third molar extraction sockets 30 and 90 days after surgery. It is thought that PRF has the potential characteristics of an autologous fibrin matrix and can accelerate the healing. To better understand the effects of PRF on healing, further research is warranted with larger sample sizes.

Role and Efficacy of L-PRFmatrix in the Regeneration of Periodontal Defect: A New Perspective

The ultimate goal of periodontal therapy is to achieve complete wound healing and regeneration of the periodontal unit. The therapeutic use of L-PRF matrix constitutes a relatively new biotechnology that has been a breakthrough in the acceleration of hard and soft tissue healing. Platelet-rich fibrin (PRF) belongs to a new generation of platelet concentrates, with simplified processing and without biochemical blood handling. The slow polymerization during PRF preparation seems to generate a fibrin network very similar to the natural one. Such a network leads to a more efficient cell migration and proliferation and thus cicatrization. This article proposes an overview of use of platelet-rich fibrin in management of periodontal hard and soft tissue defects and goes on to describe the clinical benefits of PRF and its advantage over PRP.

Platelet rich fibrin and xenograft in treatment of intrabony defect

For complete periodontal regeneration, delivery of growth factors in the local environment holds a great deal in adjunct to bone grafts. Platelet rich fibrin (PRF) is considered as second generation platelet concentrate, consisting of viable platelets, releasing various growth factors such as platelet-derived growth factor, vascular endothelial growth factor, transforming growth factor, insulin-like growth factor, epidermal growth factor and basic fibroblast growth factor. Hence, this case report aims to investigate the clinical and radiological (bone fill) effectiveness of autologous PRF along with the use of xenogenic bone mineral in the treatment of intra bony defects. Intrabony defect was treated with autologous PRF along with the use of xenogenic bone mineral. A decrease in probing pocket depth, gain in clinical attachment level and significant bone fill was observed at end of 6 months. The result obtained with the use of PRF may be attributed to the sustained and simultaneous release of various growth factors over a period of 7 days. In this case report, the positive clinical impact of additional application of PRF with xenogenic graft material in the treatment of periodontal intrabony defect was seen.

Role of platelet-released growth factors in detoxification of reactive oxygen species in osteoblasts

INTRODUCTION

Oxidative stress can impair fracture healing. To protect against oxidative damage, a system of detoxifying and antioxidative enzymes works to reduce the cellular stress. The transcription of these enzymes is regulated by antioxidant response element (ARE). The nuclear factor (erythroid-derived 2)-like2 (Nrf2) plays a major role in transcriptional activation of ARE-driven genes. Recently it has been shown that vascular endothelial growth factor (VEGF) prevents oxidative damage via activation of the Nrf2 pathway in vitro. Platelet-released growth factor (PRGF) is a mixture of autologous proteins and growth factors, prepared from a determined volume of platelet-rich plasma (PRP). It has already used to enhance fracture healing in vitro. The aim of the present study was to elucidate if platelets can lead to upregulation of VEGF and if platelets can regulate the activity of Nrf2-ARE system in primary human osteoblast (hOB) and in osteoblast-like cell line (SAOS-2).

METHODS

Platelets and PRGF were obtained from healthy human donors. HOB and SAOS-2 osteosarcoma cell line were used. The ARE activity was analysed using a dual luciferase reporter assay system. We used Western blot to detect the nuclear accumulation of Nrf2 and the amount of cytosolic antioxidant Thioredoxin Reductase-1 (TXNRD-1), Heme Oxygenase-1 (HO-1) and NAD(P)H quinine oxidoreductase-1 (NQO1). Gene expression analysis was performed by real-time RT PCR. ELISA was used for the quantification of growth factors.

RESULTS

The activity of ARE was increased in the presence of PRGF up to 50%. Western blotting demonstrated enhanced nuclear accumulation of Nrf2. This was followed by an increase in the protein expression of the aforementioned downstream targets of Nrf2. Real-time RT PCR data showed an upregulation in the gene expression of the VEGF after PRGF treatment. This was confirmed by ELISA, where the treatment with PRGF induced the protein level of VEGF in both cells.

CONCLUSIONS

These results provide a new insight into PRGF's mode of action in osteoblasts. PRGF not only leads to increase the endogenous VEGF, but also it may be involved in preventing oxidative damage through the Nrf2-ARE signalling. Nrf2 activation via PRGF may have great potential as an effective therapeutic drug target in fracture healing.