Classification of platelet concentrates: from pure platelet-rich plasma (P-PRP) to leucocyte- and platelet-rich fibrin (L-PRF)

Effect of platelet concentrates for pain and symptom management in oral lichen planus: an evidence-based systematic review

BACKGROUND

Platelet Concentrate (PC) injection therapy has shown potential as a local therapy for oral lichen planus (OLP). However, its safety and efficacy have not yet been fully established. Our research compared the efficacy of PC with topical steroid treatment in alleviating pain and symptoms related to OLP. We aims to present evidence-based alternatives that dentists can use to improve patient outcomes while reducing potential side effects.

METHODS

We conducted a systematic search of five electronic databases up to April 2023, including Embase, Cochrane Central Register of Controlled Trials, PubMed, OVID Medline, and WanFang, to evaluate PCs' efficacy compared to topical corticosteroid therapy for OLP. The literature quality was assessed using the Cochrane ROB tool. A fixed-effects model was used to determine the Weighted Mean Difference (WMD) and Mean Difference (MD) at a 95% confidence interval (CI) for pain severity and other relevant clinical indicators.

RESULTS

The comparison between topical corticosteroid therapy and PCs showed no significant difference for pain relief (WMD = -0.07, CI = 95% -0.34 to 0.19), symptom improvement (MD = -0.21, CI = 95% -0.55 to 0.13), or the severity of included lesions measured by REU scores (MD = -0.25, CI = 95% -0.32 to 0.82).

CONCLUSIONS

Locally injected PC have been found efficient in managing oral lichen planus, indicating that they are a promising alternative option to steroid therapy for OLP patients, particularly those who have not responded favorably to steroid therapy. However, further research is needed to establish determining the recurrence rate and long-term adverse effects.

TRIAL REGISTRATION

The systematic review protocol has been registered in advance with the PROSPERO database (CRD42023415372).

Progress in Regenerative Medicine: Exploring Autologous Platelet Concentrates and Their Clinical Applications

The goal of regenerative medicine is to achieve tissue regeneration. In the past, commonly used techniques included autologous or allogeneic transplantation and stem cell therapy, which have limitations, such as a lack of donor sites in the case of autologous transplantation and the invasiveness of stem cell harvesting. In recent years, research has, therefore, focused on new and less invasive strategies to achieve tissue regeneration. A step forward in this direction has been made with the development of autologous platelet concentrates (APCs), which are derived from the patient's own blood. They can be classified into three generations: platelet-rich plasma (PRP), platelet-rich fibrin (PRF), and concentrated growth factors (CGFs). These APCs have different structural characteristics, depending on the distinctive preparation method, and contain platelets, leukocytes, and multiple growth factors, including those most involved in regenerative processes. The purpose of this review is to clarify the most used techniques in the field of regenerative medicine in recent years, comparing the different types of APCs and analyzing the preparation protocols, the composition of the growth factors, the level of characterization achieved, and their clinical applications to date.

Anti-Aging Potential of Platelet Rich Plasma (PRP): Evidence from Osteoarthritis (OA) and Applications in Senescence and Inflammaging

Aging and age-related changes impact the quality of life (QOL) in elderly with a decline in movement, cognitive abilities and increased vulnerability towards age-related diseases (ARDs). One of the key contributing factors is cellular senescence, which is triggered majorly by DNA damage response (DDR). Accumulated senescent cells (SCs) release senescence-associated secretory phenotype (SASP), which includes pro-inflammatory cytokines, matrix metalloproteinases (MMPs), lipids and chemokines that are detrimental to the surrounding tissues. Chronic low-grade inflammation in the elderly or inflammaging is also associated with cellular senescence and contributes to ARDs. The literature from the last decade has recorded the use of platelet rich plasma (PRP) to combat senescence and inflammation, alleviate pain as an analgesic, promote tissue regeneration and repair via angiogenesis-all of which are essential in anti-aging and tissue regeneration strategies. In the last few decades, platelet-rich plasma (PRP) has been used as an anti-aging treatment option for dermatological applications and with great interest in tissue regeneration for orthopaedic applications, especially in osteoarthritis (OA). In this exploration, we connect the intricate relationship between aging, ARDs, senescence and inflammation and delve into PRP's properties and potential benefits. We conduct a comparative review of the current literature on PRP treatment strategies, paying particular attention to the instances strongly linked to ARDs. Finally, upon careful consideration of this interconnected information in the context of aging, we suggest a prospective role for PRP in developing anti-aging therapeutic strategies.

The effect of leukocyte- and platelet-rich fibrin on the bone loss and primary stability of implants placed in posterior maxilla: a randomized clinical trial

PURPOSE

In this study, we investigated the effects of leukocyte- and platelet-rich fibrin (L-PRF) on implant stability and alterations in the marginal bone surrounding posterior maxillary implants.

METHODS

This randomized clinical trial was conducted to compare the variable of L-PRF placement around maxillary implants. Resonance frequency analysis (RFA) was used to evaluate the implant stability immediately after surgery and at 1, 2, 4, 6, 8, and 12 weeks after surgery (t0 to t6, respectively). In addition, the amount of marginal bone changes around the implant at t6 was compared with the baseline using periapical radiography.

RESULTS

The RFA outcomes were statistically significant within each group (P < 0.001, Eta2 = 0.322); however, in none of the follow-ups and immediately after the surgery, there was a significant difference between the two groups in terms of the implant stability quotient (ISQ) scores (P > 0.05). At t0, the test and control groups' respective mean levels of marginal bone loss around the implants were 0.4836 mm and 0.7343 mm, significantly different from the corresponding values at t6. On the other hand, marginal bone loss around the implant was not significantly different between the two groups in t0 and t6 (P = 0.532).

CONCLUSIONS

L-PRF did not improve the RFA outcomes of implants three months after implant placement, and changes in the ISQ values over time were the same in both groups. In addition, L-PRF had no superior effect on the marginal bone loss around the implants.

TRIAL REGISTRATION NUMBER

The research was registered in the Iranian Registry of Clinical Trials on 22 December 2020 (No: IRCT20200624047906N1), available at http://www.irct.ir.

Current Progress of Platelet-Rich Derivatives in Cartilage and Joint Repairs

In recent years, several types of platelet concentrates have been investigated and applied in many fields, particularly in the musculoskeletal system. Platelet-rich fibrin (PRF) is an autologous biomaterial, a second-generation platelet concentrate containing platelets and growth factors in the form of fibrin membranes prepared from the blood of patients without additives. During tissue regeneration, platelet concentrates contain a higher percentage of leukocytes and a flexible fibrin net as a scaffold to improve cell migration in angiogenic, osteogenic, and antibacterial capacities during tissue regeneration. PRF enables the release of molecules over a longer period, which promotes tissue healing and regeneration. The potential of PRF to simulate the physiology and immunology of wound healing is also due to the high concentrations of released growth factors and anti-inflammatory cytokines that stimulate vessel formation, cell proliferation, and differentiation. These products have been used safely in clinical applications because of their autologous origin and minimally invasive nature. We focused on a narrative review of PRF therapy and its effects on musculoskeletal, oral, and maxillofacial surgeries and dermatology. We explored the components leading to the biological activity and the published preclinical and clinical research that supports its application in musculoskeletal therapy. The research generally supports the use of PRF as an adjuvant for various chronic muscle, cartilage, and tendon injuries. Further clinical trials are needed to prove the benefits of utilizing the potential of PRF.

Effect of platelet-rich plasma on healing of autologous graft after anterior cruciate ligament reconstruction: a randomized control trial

Aim: This study aimed to assess the effect of platelet-rich plasma (PRP) on anterior cruciate ligament (ACL) graft healing at graft tunnel interface and ACL graft 6 months post-reconstruction. Material & methods: A randomized trial involving 87 patients was conducted, dividing them into PRP and non-PRP groups. Magnetic resonance imaging (MRI) and functional outcome measures were used to evaluate graft healing. Results: Out of the 87 patients, 80 were analyzed. The PRP group exhibited superior clinical and radiological outcomes compared with the non-PRP group, as indicated by Figueroas score, Lysholm score and knee range of motion. Conclusion: These findings demonstrate that PRP can be used as an adjunct therapy for ACL reconstruction, enhancing graft healing and improving patient outcomes. CTRI approval (Reg. No - CTRI/2018/11/016263).

Effect of the use of platelet concentrates on new bone formation in alveolar ridge preservation: a systematic review, meta-analysis, and trial sequential analysis

OBJECTIVES

To investigate the histomorphometric changes occurring in alveolar ridge preservation (ARP) based on the use of different plasma concentrates (PCs) in randomized clinical trials (RCT). There is controversy whether the placement of PCs in ARP is effective in the formation of new bone.

MATERIALS AND METHODS

A systematic review search was conducted in PubMed, Scopus, Web of Science, and Cochrane Database to answer the PICO question: In patients undergoing tooth extraction followed by ARP, do PCs alone in the post-extraction socket in comparison with spontaneous healing improve new vital bone formation percentage in histomorphometric analysis after more than 10 weeks? The risk of bias was assessed and a meta-analysis was conducted.

RESULTS

Of 3809 results, 8 studies were considered suitable for inclusion. A total of 255 teeth were extracted in 250 patients. Regarding the PCs used, ARP was performed with platelet- and leukocyte-rich fibrin (L-PRF) in 120 sockets, and with pure platelet-rich plasma (P-PRP) in 31 sockets and 104 sockets were controlled. PCs improved new bone formation in ARP with respect to the spontaneous healing group (SMD = 1.77, 95%C.I. = 1.47-2.06, p-value < 000.1). There were no differences between the different PCs (L-PRF and P-PRP).

CONCLUSION

The results of this meta-analysis support the efficacy of the use of PCs in new bone formation in ARP. With respect to the different types of PCs studied, no differences were observed.

CLINICAL RELEVANCE

When planning implant surgery after tooth extraction, treatment with PCs should be considered for ARP. Any PC increases new bone formation compared to spontaneous healing.

The value of adding platelet-rich plasma (PRP) to noncultured epidermal cell suspension (NCECS) in surgical treatment of stable resistant vitiligo: A self-controlled randomised double-blinded study

BACKGROUND

Noncultured epidermal cell suspension (NCECS) is a commonly used surgical treatment for resistant stable acral vitiligo and vitiligo overlying joints. Platelet-rich plasma (PRP) has been reported to enhance the repigmentation response of different therapeutic modalities for vitiligo, including vitiligo surgery.

OBJECTIVE

To assess the value of adding of PRP to NCECS in the surgical treatment of acral vitiligo and vitiligo overlying joints.

PATIENTS AND METHODS

This self-controlled randomised trial included 15 patients with 30 lesions in which NCECS suspended in PRP was performed for one lesion and NCECS in ringer's lactate for another comparable lesion. Following NCECS, patients underwent thrice weekly excimer light sessions for 3 months. After 8 weeks, patients underwent preliminary assessment. By the end of the 3 months, both lesions were compared as regards improvement in surface area and pigmentation. Additionally, physician global assessment was made by a blinded investigator.

RESULTS

Significant improvement was reported in both lesional extent and pigmentation (after PRP and lactated ringer NCECS) with no statistical difference between them.

CONCLUSION

Despite previous promising results, suspending NCECS in PRP offered no privilege in surgical treatment of acral vitiligo and vitiligo overlying joints, which are quite resistant to treat.

PAN AFRICAN CLINICAL TRIAL REGISTRY ID

PACTR202108873035929, Date: 16 August 2021.

Platelet- Rich Plasma Treatment Supported by Ultrasound Detection of Septa in Recurrent Canine Aural Hematoma: A Case Series

Aural hematoma is a common pathological condition in veterinary practice with a high incidence rate in dogs. Drainage, corticosteroid injections, and surgical approaches represent the common treatments in these clinical cases. However, surgery leaves visible signs and is usually correlated with recurrence, scars, and deformation of the treated pinna. For this reason, more effective and less invasive methods have been proposed over the years. Platelet-Rich Plasma (PRP) is one of the most promising options due to its pro-regenerative properties and capability to modulate the inflammatory state. The present work reports 12 cases of canine aural hematoma treated with PRP. The PRP treatment was combined with an ultrasound evaluation of the pinna to detect and treat all involved septa. The results show that relatively large volumes (2 mL) of PRP associated with an ultrasound guide are safe and efficacious in the treatment of canine aural hematoma requiring a maximum of two infiltrations, both in acute and chronic conditions. All the patients recovered their normal ear thickness (compared with the controlateral one) without relapses, averaging 38.5 days from their first treatment (10-90 days; SD: 24.7). The key role of PRP combined with a tailored diagnosis process carried out by the veterinarian, which included using an ultrasound system and the proper bandage, suggests that this approach may represent a valid alternative to surgery and corticosteroids.

Formation of Hydroxyapatite-Based Hybrid Materials in the Presence of Platelet-Poor Plasma Additive

Biomaterials based on hydroxyapatite with controllable composition and properties are promising in the field of regenerative bone replacement. One approach to regulate the phase composition of the materials is the introduction of biopolymer-based additives into the synthesis process. The purpose of present study was to investigate the formation of hydroxyapatite-based hybrid materials in the presence of 6-24% platelet-poor plasma (PPP) additive, at a [Ca2+]/[PO43-] ratio of 1.67, pH 11, and varying maturing time from 4 to 9 days. The mineral component of the materials comprised 53% hydroxyapatite/47% amorphous calcium phosphate after 4 days of maturation and 100% hydroxyapatite after 9 days of maturation. Varying the PPP content between 6% and 24% brought about the formation of materials with rather defined contents of amorphous calcium phosphate and biopolymer component and the desired morphology, ranging from typical apatitic conglomerates to hybrid apatite-biopolymer fibers. The co-precipitated hybrid materials based on hydroxyapatite, amorphous calcium phosphate, and PPP additive exhibited increased solubility in SBF solution, which defines their applicability for repairing rhinoplastic defects.

Platelet-Rich Plasma Power-Mix Gel (ppm)-An Orthobiologic Optimization Protocol Rich in Growth Factors and Fibrin

Platelet- and fibrin-rich orthobiologic products, such as autologous platelet concentrates, have been extensively studied and appreciated for their beneficial effects on multiple conditions. Platelet-rich plasma (PRP) and its derivatives, including platelet-rich fibrin (PRF), have demonstrated encouraging outcomes in clinical and laboratory settings, particularly in the treatment of musculoskeletal disorders such as osteoarthritis (OA). Although PRP and PRF have distinct characteristics, they share similar properties. The relative abundance of platelets, peripheral blood cells, and molecular components in these orthobiologic products stimulates numerous biological pathways. These include inflammatory modulation, augmented neovascularization, and the delivery of pro-anabolic stimuli that regulate cell recruitment, proliferation, and differentiation. Furthermore, the fibrinolytic system, which is sometimes overlooked, plays a crucial role in musculoskeletal regenerative medicine by regulating proteolytic activity and promoting the recruitment of inflammatory cells and mesenchymal stem cells (MSCs) in areas of tissue regeneration, such as bone, cartilage, and muscle. PRP acts as a potent signaling agent; however, it diffuses easily, while the fibrin from PRF offers a durable scaffolding effect that promotes cell activity. The combination of fibrin with hyaluronic acid (HA), another well-studied orthobiologic product, has been shown to improve its scaffolding properties, leading to more robust fibrin polymerization. This supports cell survival, attachment, migration, and proliferation. Therefore, the administration of the "power mix" containing HA and autologous PRP + PRF may prove to be a safe and cost-effective approach in regenerative medicine.

Clinical Efficacy of Platelet Derivatives in Periodontal Tissue Regeneration: An Umbrella Review

Objectives

This umbrella review aimed to consolidate the best available evidence regarding the clinical efficacy of platelet derivatives in the treatment of periodontal defects associated with periodontitis and in the management of mucogingival deformities.

Materials and Methods

The "umbrella review" strategy was used to identify systematic reviews and meta-analyses. The search was performed without language restrictions and updated at the end of February 2023. The PubMed and Scopus databases, together with gray literature, were included in the search.

Results

The search yielded 412 studies. Subsequently, 12 articles were selected for further examination based on relevance. Finally, eight systematic reviews and meta-analyses were assessed. Regarding intrabony defects, in terms of clinical attachment level (CAL) gain, platelet-rich fibrin (PRF) was observed to lead to a statistically significant attachment gain compared to surgical therapy alone. PRF was also found to show greater CAL gain compared to platelet-rich plasma (PRP) and other biomaterials. The parameter probing depth decreased significantly when PRF was used compared to surgical therapy alone (P < 0.05). Similar results were seen when leukocyte- and platelet-rich fibrin (L-PRF) was applied. In terms of radiographic bone fill, both PRF and PRP showed significantly greater bone fill compared to surgical therapy. Regarding the results of periodontal plastic surgery, PRF favored a slight root coverage compared to the coronally displaced flap. This result depended on the number of PRF and L-PRF membranes used, but Emdogain or connective tissue graft produced better results regardless. However, an improvement in the healing of periodontal tissues was reported.

Conclusions

Therapies with platelet derivatives applied to intrabony defects provided superior regenerative results compared to monotherapies, except in the case of root coverage.

A survey on awareness and knowledge among dentist practicing regenerative endodontics towards current regenerative endodontic protocols and the scaffolds used in regenerative dentistry

There are many inconsistencies in the protocols followed for Regenerative Endodontic Procedures (REP's).This study was formulated with an aim to conduct a survey among Pediatric Dentists, Endodontists and General Practioners treating Necrotic young permanent teeth to examine their awareness and Knowledge on Current Regenerative Endodontic Protocols and Scaffolds used in regenerative dentistry.

Methods

A Cross-Sectional Survey was carried out amongst 100 Pediatric dentists,100 Endodontists and 100 General Practioners. It was web-based survey and the questionnaire was formulated and all the items in the questionnaire were tested for reliability and validity before circulation of the questionnaire for the purpose of the study.

Results

The results of the study indicated that all the three groups were unaware that failure of cases should be reported to AEE (American Academy of Endodontics) REP Database and only 20.2, 20.1 and 0.3 % of Pediatric dentists,Endodontists and General Dentists preferred Regenerative Dentistry as a clinical protocol for REP. With respect to knowledge regarding irrigation and disinfection procedures all three groups were lacking in the knowledge regarding intracanal medicament for disinfection and the irrigation solutions.

Conclusion

There is a lack of homogeneity in protocols followed for REP among those practicing Regenerative Endodontics as a protocol. Since it's an evolving science there is a need to bring about a uniformity in practices to increase the evidences to support the causal effect relation of regenerative endodontics.

Impact of titanium-prepared platelet-rich fibrin in type 1 fascia graft tympanoplasty on graft survival and hearing outcomes

Background

Type 1 fascia graft tympanoplasty (T1FGT) is the mainstay surgical approach for the treatment of tympanic membrane perforations. The most widely used graft material is temporal muscle fascia, and graft take rates are reported differently. The methods to enhance graft take are still being investigated. Aim: The aim of our study was to investigate the effect of titanium-prepared platelet-rich fibrin (T-PRF) on graft take and hearing outcomes in T1FGT.

Materials and Methods

Fifty-seven ears eligible for T1FGT were involved in the study and prospectively evaluated. T-PRF was applied with T1FGT in 27 ears. Thirty ears in the other group underwent only T1FGT. The patients underwent an otomicroscopic and audiometric examination in preoperative and postoperative 2nd week, 1st month, and 6th month. Both groups were evaluated in terms of hearing levels, infection, and graft take rates.

Results

Two patients in the T1FGT + T-PRF group and seven patients in the T1FGT group had postoperative perforation (graft take rate: 92.6% versus 76.7%). The graft take rate was found to be increased in the T-PRF group although the difference was not statistically significant. In the T1FGT group, the percentage of infection was higher than in the T1FGT + T-PRF group. When the preoperative and postoperative 6th-month audiometry was compared, a statistically significant hearing gain was obtained for both groups.

Conclusion

In the treatment of tympanic membrane perforations, T-PRF applied over the fascia graft was shown to increase graft take rates and decrease the probability of infection. Further studies with larger samples are needed to demonstrate the effects of PRF.

The Invasive Management of Pain: Diagnosis and New Treatment Options

Both the diagnosis and treatment of pain are evolving, especially in interventional approaches. Diagnosis of low back pain combines old and new methodologies, in particular, it involves an expanded role for ultrasound. While low back pain is a common complaint, there are many etiologies to the condition which must be explored before a final diagnosis can be made and treatment planned. Tumors and infections are rarely involved in low back pain but should be ruled out in the initial phase itself since failing to address them early can have devastating consequences. Some invasive treatments seem promising in the management of low back pain. Treating musculoskeletal pain with regenerative medicine, such as platelet-rich plasma, holds great promise. Autologous blood products are safe and may help stimulate the body's own responses for regeneration. The so-called "orthobiologics" play a role in sports medicine and the treatment of musculoskeletal pain. Neuromodulation, especially spinal cord stimulation, is undergoing a renaissance with new waveforms, devices, and a greater albeit incomplete understanding of its mechanisms of action. Spinal cord stimulation is not a first-line therapy and not all patients or all back problems respond to this treatment. Nevertheless, the therapy can be safe, effective, and cost-effective with appropriate patient selection. Radiofrequency ablation of nerves in the form of neurotomy can be effective in reducing the pain of osteoarthritis. These procedures, including the newer cooled radiofrequency neurotomy, can restore function, reduce pain, and may potentially have an opioid-sparing effect. Technical expertise in nerve and anatomy is needed for the use of this technique. This review article aims to provide updated information on some invasive intervention techniques in pain management.

Autologous microfragmented adipose tissue and leukocyte-poor platelet-rich plasma combined with hyaluronic acid show comparable clinical outcomes for symptomatic early knee osteoarthritis over a two-year follow-up period: a prospective randomized clinical trial

PURPOSE

The purpose of this prospective randomized clinical trial is to compare the clinical outcomes of three injections of leucocyte-poor platelet-rich plasma (LP-PRP) and hyaluronic acid (HA) to a single dose of autologous microfragmented adipose tissue (AMAT) in patients with mild osteoarthritis at a two-year follow-up.

METHODS

Eighty symptomatic knees in fifty patients (mean age: 62.38 ± 11.88 years) with Kellgren-Lawrence grade 0 to 2 osteoarthritis were non blinded, randomly allocated into two equal groups. Group 1 consisted of 40 knees that received autologous LP-PRP + HA; Group 2 consisted of 40 knees treated with a single dose of AMAT injection. The outcomes were measured by Tegner, Marx, Visual Analogue Scale (VAS) for pain, International Knee Documentation Committee, and Knee Injury and Osteoarthritis Outcome Score (KOOS) at 6 (T1), 12 (T2), and 24 (T3) months. Adverse events were recorded at each follow-up timepoint. To assess score differences among subjects of the same gender and age, a subgroup analysis was performed.

RESULTS

Both groups had significant clinical and functional improvement at 6, 12, and 24 months (p < 0.05). Comparing the two groups, the AMAT groups showed significantly higher pre-operative Marx score (3.35 ± 4.91 vs. 1.78 ± 3.91) and VAS score (5.03 ± 2.02 vs. 3.85 ± 1.68) (p < 0.05), higher VAS (3.89 ± 2.51 vs. 2.64 ± 2.00) at T2 and KOOS-ADL (79.60 ± 20.20 vs. 65.68 ± 23.62), and lower KOOS-Sports (50.30 ± 30.15 vs. 68.35 ± 30.39) at T3 (p < 0.05). No patient from either group had experienced major adverse effects. In the LP-PRP group 12 (30%) patients presented swelling, redness, and mild pain for one day after injection and two patients had synovitis for two days and required paracetamol and local ice. In AMAT group 5 (12.5%) patients had ecchymosis and bruising at the fat aspiration site for three days.

CONCLUSION

AMAT did not show significant superior clinical improvement compared with three LP-PRP combined with HA injections in terms of functional improvement at different follow-up points. Both procedures were safe with no major complications reporting good results at mid-term follow-up, improving knee function, pain, and quality of live regardless of age and gender.

LEVEL OF EVIDENCE

Level I-Prospective Randomized Clinical Trial.

The impact of membrane perforation and L-PRF for vertical ridge augmentation with a xenogeneic block graft: an experimental study in a canine model

OBJECTIVES

This study evaluated clinically and histologically the efficacy of modified perforated collagen membrane (PCM) and/or leukocyte- and platelet-rich fibrin (L-PRF) in combination with xenogeneic block bone graft in the vertical alveolar ridge augmentation.

MATERIALS AND METHODS

Six adult mongrel dogs were enrolled in this randomized blinded study. After defect preparation, xenogeneic screw-fixed block graft was covered by an occlusive collagen membrane in group 1 that represented the control group (Block + CM). In group 2, L-PRF membrane was added first before top coverage by occlusive collagen membrane (Block + L-PRF + CM). Groups 3 (Block + PCM) and 4 (Block + L-PRF + PCM) were identical to the first two groups except that the occlusive collagen membrane was replaced by a perforated one. Following a healing period of 2 months, the dogs were submitted to the surgical reentry phase for clinical and histological evaluation.

RESULTS

Clinically, no significant differences were found among all groups regarding vertical and horizontal ridge dimensions (p = 0.155, 0.492, respectively). Histomorphometric analysis revealed that the percentage of the total bone area and mature bone was significantly higher in group 4 (69.36 ± 2.72, 33.11 ± 5.18) compared to the control group (59.17 ± 4.27, 21.94 ± 2.86) (p = 0. 027, p = 0.029).

CONCLUSION

The use of xenogenic block grafts in combination with a double-layered perforated collagen L-PRF membrane in vertical ridge augmentation appeared to improve the inductive power of this challenging defect type.

CLINICAL RELEVANCE

Size and number of perforations may affect the mechanical and handling properties of the membrane.

Efficacy and safety of platelet-rich plasma injections for the treatment of osteoarthritis: a systematic review and meta-analysis of randomized controlled trials

Background

In recent years, platelet-rich plasma (PRP) injections for osteoarthritis (OA) have been widely promoted in clinical practice, but their effectiveness is controversial. Therefore, we conducted a meta-analysis of relevant randomized controlled trials (RCTs) to determine the efficacy and safety of PRP injections for the treatment of OA.

Methods

We searched databases including Embase, Web of Science, Medline, PubMed, and the Cochrane Library for relevant studies. Two researchers (YQX and CG) performed literature screening, baseline data extraction, literature quality assessment, and heterogeneity analysis of RCTs from the retrieved studies. Based on the magnitude of heterogeneity I², random-effects or fixed-effects models were selected for the meta-analysis.

Results

We included 24 RCTs comprising 1344 patients with OA who met the inclusion criteria, with the main types of morbidity being knee osteoarthritis (KOA), hip osteoarthritis (HOA), ankle osteoarthritis (AOA), and temporomandibular joint osteoarthritis (TMJOA). Our results indicate that PRP injections were effective in improving Visual Analog Scale (VAS) pain scores in patients with KOA, HOA, and AOA compared to controls (AOA, MD = -1.15, CI = 95% [-1.74, -0.56], I² = 40%, P < 0.05; KOA, MD = -1.03, CI = 95% [-1.16, -0.9], I² = 87%, P < 0.05; TMJOA, MD = -1.35, CI = 95% [-1.74, -0.97], I² = 92%, P < 0.05) but showed no significant efficacy in patients with HOA (MD = -0.27, CI = 95% [-0.8, 0.26], I² = 56%, P>0.05). Compared to controls, PRP injections were effective in improving Knee Injury and Osteoarthritis Outcome Score (KOOS), including the patient's pain symptoms, activities of daily living (ADL), and adhesion symptomatology, but not for that of sports function (KOOS-pain, MD = 2.77, CI = 95% [0, 5.53], I² = 0%, P < 0.05; KOOS-symptoms, MD = 3.73, CI = 95% [0.76, 6.71], I² = 0%, P < 0.05; KOOS-ADL, MD = 3.61, CI = 95% [0.79, 6.43], I² = 0%, P < 0.05; KOOS-QOL, MD = 4.66, CI = 95% [0.98, 8.35], I² = 29%, P < 0.05, KOOS-sport, MD = 0.48, CI = 95% [-3.02, 3.98], I² = 0%, P > 0.05). PRP injections were effective in improving Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores, including pain, stiffness, and functional joint motion, in patients with OA compared with the control group (WOMAC-pain, MD = -1.08, CI = 95% [-1.62, -0.53], I² = 87%, P < 0.05; WOMAC-stiffness, MD = -1.17, CI = 88% [-1.72, -0.63], I² = 87%, P < 0.05; WOMAC-function, MD = -1.12, CI = 95% [-1.65, -0.58], I² = 87%, P < 0.05). In addition, subgroup analysis showed that leukocyte-poor (LP) PRP injections were more effective than leukocyte-rich (LR) PRP injections in improving pain symptoms in patients with OA (VAS, LR-PRP, MD = -0.81, CI = 95% [-1.65, -0.03], I² = 83%, P = 0.06 > 0.05; LP-PRP, MD = -1.62, CI = 95% [-2.36, -0.88], I² = 92%, P < 0.05). A subgroup analysis based on injection sites showed that no statistical difference in efficacy between intra-articular (IA) combined with intra-osseous (IO) simultaneous PRP injections. IA PRP injections only improved VAS pain scores in patients with OA (IA+IO PRP injections, MD = -0.74, CI =95% [-1.29, -0.18], I² = 61%, P < 0.05; IA PRP injections, MD = -1.43, CI = 95% [-2.18, -0.68], I² = 87%, P < 0.05, test for subgroup differences, P > 0.05, I² = 52.7%).

Conclusion

PRP injection therapy can safely and effectively improve functional activity in patients with OA and produce positive analgesic effects in patients with KOA, TMJOA, and AOA. However, PRP injection therapy did not significantly reduce pain symptoms in patients with HOA. In addition, the analgesic effect of LP-PRP was greater than that of LR-PRP.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022362066.

Effect of an intraoperative periradicular application of platelet-rich fibrin (PRF) on residual post-surgical neuropathic pain after disc herniation surgery: study protocol for NeuroPRF, a randomized controlled trial

BACKGROUND

The prevalence of post-surgical lumbar neuropathic radiculopathy is approximately 30%. Poor response to the recommended treatments for neuropathic pain, namely antidepressants and/or gabapentinoids, requires the development of new techniques to prevent chronic pain. One such well-tolerated technique is the administration of autologous plasma enriched in platelets and fibrin (PRF). This approach is largely used in regenerative medicine owing to the anti-inflammatory and analgesic properties of PRF. It could also be an interesting adjuvant to surgery, as it reduces neurogenic inflammation and promotes nerve recovery, thereby reducing the incidence of residual postoperative chronic pain. The aim of the present study is to evaluate the benefit of periradicular intraoperative application of PRF on the residual postsurgical neuropathic pain after disc herniation surgery.

METHODS

A randomized, prospective, interventional, controlled, single-blind study with evaluation by a blind outcome assessor will be performed in Strasbourg University Hospital. We will compare a control group undergoing conventional surgery to an experimental group undergoing surgery and periradicular administration of PRF (30 patients in each arm). The primary outcome is the intensity of postoperative neuropathic radicular pain, measured by a visual analog scale (VAS) at 6 months post-surgery. The secondary outcomes are the characteristics of neuropathic pain (NPSI), the quality of life (SF-12 and PGIC), the presence of anxiety/depression symptoms (HAD), and the consumption of analgesics. We will also carry out transcriptomic analysis of a panel of pro- and anti-inflammatory cytokines in blood samples, before surgery and at 6 months follow-up. These gene expression results will be correlated with clinical data, in particular, with the apparition of postoperative neuropathic pain.

DISCUSSION

This study is the first randomized controlled trial to assess the efficacy of PRF in the prevention of neuropathic pain following surgery for herniated disc. This study addresses not only a clinical question but will also provide information on the physiopathological mechanisms of neuropathic pain.

TRIAL REGISTRATION

This study is registered at ClinicalTrials.gov: NCT05196503 , February 24, 2022.

Evaluation of Bone Regenerative Capacity in Rabbit Femoral Defect Using Thermally Disinfected Bone Human Femoral Head Combined with Platelet-Rich Plasma, Recombinant Human Bone Morphogenetic Protein 2, and Zoledronic Acid

This research aimed to assess the effect of bone allograft combined with platelet-rich plasma (PRP), recombinant human bone morphogenetic protein-2 (rhBMP-2), and zoledronic acid (Zol) on bone formation. A total of 96 rabbits were used, and femoral bone defects (5 mm) were created. The rabbits were divided into four groups: (1) bone allograft with PRP (AG + PRP), (2) bone allograft with rhBMP-2 5 μg (AG + BMP-2), (3) bone allograft with Zol 5 μg (AG + Zol), and (4) bone allograft (AG). A histopathological examination was performed to evaluate bone defect healing after 14, 30, and 60 days. The new bone formation and neovascularization inside the bone allograft was significantly greater in the AG + PRP group compared to AG and AG + Zol groups after 14 and 30 days (p < 0.001). The use of bone allograft with rhBMP-2 induced higher bone formation compared to AG and AG + Zol groups on days 14 and 30 (p < 0.001), but excessive osteoclast activity was observed on day 60. The local co-administration of Zol with a heat-treated allograft inhibits allograft resorption as well as new bone formation at all periods. In conclusion, this study demonstrated that PRP and rhBMP-2, combined with a Marburg bone allograft, can significantly promote bone formation in the early stage of bone defect healing.

Adult-Onset Linear Morphea (en coupe de sabre) of the Face Successfully Treated with Photoactivated Low-Temperature Platelet-Rich Plasma: A Valid Therapeutic Option

Localized scleroderma (also known as morphea) is a chronic autoimmune disorder characterized by depressed, fibrotic, and dyschromic cutaneous lesions. It has a significant impact on the patient's daily life due to the unaesthetic evolution of the cutaneous lesions. Morphea is clinically divided into linear, circumscribed (plaque), generalized, pansclerotic, and mixed forms. Linear morphea en coupe de sabre (LM) usually arises in childhood. However, in about 32% of cases, it may arise in adulthood, showing a more aggressive course with also an increased risk of systemic involvement. Methotrexate is the first-line treatment for LM, although systemic steroids, topical agents (corticosteroids and calcineurin inhibitors), hyaluronic acid injections, and hydroxychloroquine or mycophenolate mofetil are valid therapeutic options. In any case, these treatments are not always effective and sometimes can be associated with important side effects and/or not tolerated by the patients. In this spectrum, platelet-rich plasma (PRP) injection can be considered a valid and safe alternative since PRP injections in the skin induce the release of anti-inflammatory cytokines and growth factors, thus reducing inflammation and increasing collagen remodeling. Herein, we describe a successful treatment of an adult-onset LM en coupe de sabre with photoactivated low-temperature PRP (Meta Cell Technology Plasma) sessions, showing an important local improvement of the lesion and patient satisfaction.

Is L-PRF an effective hemostatic agent in single tooth extractions? A cohort study on VKA and DOAC patients

OBJECTIVES

The aim of this clinical observational study was to assess the efficacy of L-PRF as a hemostatic agent in patients under treatment with vitamin K antagonists (VKAs) or direct oral anticoagulants (DOACs).

MATERIALS AND METHODS

Patients under oral anticoagulant therapy (VKA or DOACs) who needed a single simple tooth extraction were enrolled. L-PRF plug was positioned inside the alveolus and secured with non-absorbable sutures. Surgical time, pain-VAS, paracetamol intake, intra-operative, post-operative biological complications, and bleeding events have been registered.

RESULTS

A total of 112 patients (59 patients for DOAC and 53 for VKA group) were enrolled. Post-operative bleeding was recorded in nine patients (17%) for VKA group and nine patients (15.3%) for DOACs group. None of the patients needed a medical support for managing of bleeding. Seven days after surgery, no cases of post-extractive complications occurred.

CONCLUSIONS

The use of L-PRF resulted in limited mild late post-operative bleedings without the need of medical intervention.

CLINICAL RELEVANCE

The use of L-PRF can be adopted for an uneventful post-operative curse in anticoagulated patients without chasing their therapy for single tooth extraction.

The Effect of Advanced Platelet-Rich Fibrin in Tissue Regeneration in Reconstructive and Graft Surgery: Systematic Review

This systematic review answered the guiding question using the PICO system: "What are the effects of advanced platelet-rich fibrin (A-PRF) on alveolar ridge preservation and tissue gain in reconstructive and jaw graft surgery?" Searches were performed in the PubMed|MEDLINE, Scopus, Embase, Web of Science, Cochrane Library, and LILACS|bvs databases. In total, 573 articles were found in the initial search, and 564 were evaluated after the removal of duplicates, of which 5 randomized controlled trials met the eligibility criteria and were included 2 studies investigated the effect of A-PRF on the preservation of the bone ridge, 1 study evaluated the tissue repair after tooth extraction with A-PRF, 1 evaluated the peri-implant gap filling with A-PRF-xenograft mixture, and other the A-PRF on the treatment of alveolar osteitis. Advanced-PRF preparation protocol varied between the included studies from 8 to 13 minutes of centrifugation, at 1300 RPM (200 g ). The use of A-PRF provided greater dimensions of height and more favorable maintenance of the ridge profile, probing depth, and gingival margin level after extraction. Advanced-PRF also increased bone density, vital bone, epithelial healing, and control of postoperative pain and swelling after tooth extraction and in the treatment of alveolar osteitis.

Intrauterine instillation of autologous platelet-rich plasma in infertile females with thin endometrium undergoing intrauterine insemination: an open-label randomized controlled trial

BACKGROUND

Thin endometrium in infertile female patients has always been a clinical challenge for the treating reproductive physicians.

OBJECTIVE

This study aimed to evaluate the effect of intrauterine instillation of autologous platelet-rich plasma on endometrial thickness and vascularity in infertile female patients with thin endometrium undergoing ovarian stimulation with intrauterine insemination.

STUDY DESIGN

This prospective randomized control study included 120 women undergoing ovarian stimulation with intrauterine insemination, aged between 21 and 37 years, with persistent thin endometrium (<7 mm) on ≥1 cycle in previous ovarian stimulation cycles, even after conventional treatment with estradiol valerate. The women were randomly assigned to study group A and control group B. Baseline endometrial thickness and endometrial vascularity were noted. Intrauterine instillation of autologous platelet-rich plasma was done on the day of trigger in group A, whereas estradiol valerate was given in group B. Another evaluation of endometrial parameters was done on the day of intrauterine insemination. The cycle was repeated for 3 cycles or until the pregnancy was achieved, whichever occurred earlier. Parameters were noted for both groups. Primary outcomes were the change in endometrial thickness and endometrial vascularity. Secondary outcomes were positive pregnancy rate and clinical pregnancy rate.

RESULTS

In group A, mean pre-platelet-rich plasma endometrial thickness was 4.66±0.79 mm, which significantly increased to 7.47±0.85 mm after platelet-rich plasma instillation (P<.05) after 3 cycles. This increase was significantly greater than that observed in group B. There was significant increase in endometrial vascularity in group A compared with group B (P<.05). The positive pregnancy rate and clinical pregnancy rate in group A were 23.73% and 18.64%, respectively, and significantly higher than those in group B.

CONCLUSION

Autologous platelet-rich plasma is a promising, easily procurable, and novel option for management of infertile females with thin endometrium not responding to conventional treatment. Using it in intrauterine insemination cycles can reduce costs and psychological burden of this subgroup of women by reducing the need for resorting to advanced options such as in vitro fertilization and surrogacy.

Use of Leukocyte-rich and Platelet-rich Fibrin (L-PRF) Adjunct to Surgical Debridement in the Treatment of Stage 2 and 3 Medication-Related Osteonecrosis of the Jaw

Medication-related osteonecrosis of the jaw (MRONJ) is characterized by exposed necrotic bone persisting for more than 8 weeks in the maxillofacial region in patients using antiresorptive or antiangiogenetic drugs for several treatment options like bone metastasis or osteoporosis. There are several treatment options studied in scientific literature, and one of them with promising results is using platelet concentrates adjunct to surgical therapy. The aim of this study is to examine the therapeutic effect of leukocyte and platelet-rich fibrin (L-PRF) on patients with MRONJ. This 2-centered study investigated patients referred to oral and maxillofacial surgery departments of 2 university clinics between the years 2014 and 2020 with the diagnosis of MRONJ. Demographic data, the indication of the drug usage, drug type, duration, administration route, and systemic comorbidities of the patients were recorded. L-PRF was applied to 20 osteonecrotic lesions of 19 patients following surgical debridement. The male/female ratio was 5/14. Except 1 of the patients, all of the indications of medication were neoplasia-related. The mean follow-up period of patients was 27.9±9.2 months. Most common antirezorptive drug was zoledronate (84.2%). Complete resolution was observed in 16 necrosis sites (80%). It could be concluded that the use of L-PRF may represent an important adjunct in the surgical management of MRONJ.

Lower extremity ultrasound-guided interventions: tendon, ligament, and plantar fascia

Lower extremity tendinopathy and soft tissue injury are common clinical problems that can cause significant disability. Ultrasound-guided minimally invasive treatments using orthobiologics and image-guided percutaneous treatments continue to gain relevance with an ever-growing body of literature. We review the indications, technique, risks, and benefits according to the literature of common ultrasound-guided interventions utilized in the lower extremities.

A comparative analysis between intra articular injections of injectable platelet rich fibrin versus platelet rich plasma in the management of temporomandibular disorders: A randomized control trial

Background

Platelet concentrate has become an increasingly popular alternative source of growth factors for several types of dental and surgical procedures. It improves healing and stimulates cell proliferation, matrix remodeling, and angiogenesis. The injectable platelet-rich fibrin (i-PRF) has various advantages over platelet-rich plasma (PRP). The aim of our study was to evaluate the efficacy of intra-articular injections of i-PRF versus PRP in the management of temporomandibular disorders (TDMs).

Method

The prospective randomized study involved 14 patients (N = 28 joints) of internal derangement between the age groups of 20 to 50 years divided randomly into two groups with seven patients (N = 14 joints) in each group. For all the patients, arthrocentesis was carried out in the first sitting followed by intra-articular injections of PRP and i-PRF in group I and group II, respectively, at 1-month interval for 6 months. A single surgeon has performed the procedure. All patients were assessed clinically for pain, maximal mouth opening (MMO), lateral movement, protrusive movement, and joint sounds and radiographically for disc position and joint effusion (JE).

Results

Pain reduction, MMO, lateral movement, protrusive movement, and joint sounds were significant in both groups with more significance in group II. Disc position had improved toward normal in both groups and showed significant changes in both groups at the 9-month follow-up with better results in group II.

Conclusion

PRP and i-PRF injections are regarded as simple and safe methods with potential beneficial effects and are cost-effective. In this preliminary study, i-PRF has been found to be scoring better in terms of efficacy over PRP across all set parameters.

Advances in Platelet-Rich Plasma Treatment for Spinal Diseases: A Systematic Review

Spinal diseases are commonly associated with pain and neurological symptoms, which negatively impact patients' quality of life. Platelet-rich plasma (PRP) is an autologous source of multiple growth factors and cytokines, with the potential to promote tissue regeneration. Recently, PRP has been widely used for the treatment of musculoskeletal diseases, including spinal diseases, in clinics. Given the increasing popularity of PRP therapy, this article examines the current literature for basic research and emerging clinical applications of this therapy for treating spinal diseases. First, we review in vitro and in vivo studies, evaluating the potential of PRP in repairing intervertebral disc degeneration, promoting bone union in spinal fusion surgeries, and aiding in neurological recovery from spinal cord injury. Second, we address the clinical applications of PRP in treating degenerative spinal disease, including its analgesic effect on low back pain and radicular pain, as well as accelerating bone union during spinal fusion surgery. Basic research demonstrates the promising regenerative potential of PRP, and clinical studies have reported on the safety and efficacy of PRP therapy for treating several spinal diseases. Nevertheless, further high-quality randomized controlled trials would be required to establish clinical evidence of PRP therapy.

Orthobiologics: a review

PURPOSE

The use of biologic materials in orthopaedics (orthobiologics) has gained significant attention over the past years. To enhance the body of the related literature, this review article is aimed at summarizing these novel biologic therapies in orthopaedics and at discussing their multiple clinical implementations and outcomes.

METHODS

This review of the literature presents the methods, clinical applications, impact, cost-effectiveness, and outcomes, as well as the current indications and future perspectives of orthobiologics, namely, platelet-rich plasma, mesenchymal stem cells, bone marrow aspirate concentrate, growth factors, and tissue engineering.

RESULTS

Currently available studies have used variable methods of research including biologic materials as well as patient populations and outcome measurements, therefore making comparison of studies difficult. Key features for the study and use of orthobiologics include minimal invasiveness, great healing potential, and reasonable cost as a nonoperative treatment option. Their clinical applications have been described for common orthopaedic pathologies such as osteoarthritis, articular cartilage defects, bone defects and fracture nonunions, ligament injuries, and tendinopathies.

CONCLUSIONS

Orthobiologics-based therapies have shown noticeable clinical results at the short- and mid-term. It is crucial that these therapies remain effective and stable in the long term. The optimal design for a successful scaffold remains to be further determined.

Platelet-rich plasma-loaded bioactive chitosan@sodium alginate@gelatin shell-core fibrous hydrogels with enhanced sustained release of growth factors for diabetic foot ulcer healing

The ability of autologous platelet-rich plasma (PRP) gel to promote rapid wound healing without immunological rejection has opened new avenues for the treatment of diabetic foot wounds. However, PRP gel still suffers from the quick release of growth factors (GFs) and requires frequent administration, thus resulting in decreased wound healing efficiency, higher cost as well as greater pain and suffering for the patients. In this study, the flow-assisted dynamic physical cross-linked coaxial microfluidic three-dimensional (3D) bio-printing technology, combined with the calcium ion chemical dual cross-linking method was developed to design PRP-loaded bioactive multi-layer shell-core fibrous hydrogels. The prepared hydrogels exhibited outstanding water absorption-retention capacity, good biocompatibility as well as a broad-spectrum antibacterial effect. Compared with clinical PRP gel, these bioactive fibrous hydrogels displayed a sustained release of GFs, reducing the administration frequency by 33 % availably during the wound treatment, but more prominent therapeutic effects such as effective reduced inflammation, in addition to promoting the growth of granulation tissue and angiogenesis, the formation of high-density hair follicles, and the generation of regular ordered and high-density collagen fiber network, which suggested great promise as exceptional candidates for treatment of diabetic foot ulcer in clinical settings.

Platelet-rich Plasma Improves Radiotherapy-induced Emotional Disorder and Cognitive Dysfunction, Neuroinflammation in Aged Rats by Inhibiting the Activation of NLRP3 Inflammasomes

Although radiotherapy (RT) is the preferred treatment for elderly patients with brain tumors, certain negative effects can't be ignored. Fortunately, platelet-rich plasma (PRP) presents with a promising potential for the treatment of neurological diseases. Therefore, this study aimed to explore the effect of PRP on neuroinflammation, emotional disorder and cognitive dysfunction induced by RT in aged rats. Firstly, whole brain RT (WBRT) model was established by whole brain irradiation with 10 Gy of 6-MeV electron beam in rats. Next, twenty 20-month-old female SD rats were divided into four groups (sham group, PRP group, WBRT group, and WBRT + PRP group) according different treatments. After that, the cognitive dysfunction and depression-like behavior of rats were examined by novel object recognition test (NORT), Morris water maze test (MWM), open field test (OFT) and elevated plus maze test (EPM). Besides, immunohistochemistry was used to detect the expression of microglial marker protein Iba-1 in rat hippocampus; enzyme linked immunosorbent assay (ELISA) to examine the levels of pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1 beta (IL-1β), IL-18, and monocyte chemoattractant protein 1 (MCP-1) in rat hippocampus; real-time quantitative reverse transcription PCR (qRT-PCR) and western blot to measure the levels of neurotrophic factors brain-derived neurotrophic factor (BDNF), tropomyosin-related kinase B receptor (TrkB), and nerve growth factor (NGF) in rat hippocampus; and western blot also to observe the protein expression levels of NOD-like receptor protein 3 (NLRP3), caspase-1, apoptosis-associated speck-like protein containing a CARD (ASC), and IL-1β in rat hippocampus. After experiments, some results obtained were shown as follows. PRP could significantly improve learning and memory ability and depression-like behavior, increase the level of neurotrophic factors, inhibit the activation of microglia and decrease the level of pro-inflammatory factors in WBRT rats. In addition, PRP significantly inhibited the activation of NLRP3 inflammasomes. To sum up, PRP can ameliorate neuroinflammation, emotional disorder and cognitive dysfunction induced by RT in aged rats, and the mechanism may be related to its inhibitory effect on NLRP3 inflammasome activation.

Leukocyte-Rich and Platelet-Rich Fibrin for Skull Base Reconstruction After Endoscopic Endonasal Skull Base Surgery

BACKGROUND

Postoperative cerebrospinal fluid (CSF) leak is one of the most common complications after endoscopic endonasal approach to the skull base.

OBJECTIVE

To analyze the effect of leukocyte-rich and platelet-rich fibrin (L-PRF) as part of a standardized endonasal skull base repair protocol on postoperative infection and CSF leak rate.

METHODS

One hundred three patients who underwent an endoscopic endonasal approach and were reconstructed using a standard technique (Group A) were compared with 139 patients using the same protocol with the addition of L-PRF (Group B). Postoperative intracranial infection and CSF leak at 6 months were analyzed.

RESULTS

In patients with intraoperative CSF leak, postoperative leak occurred in 10.8% in Group A and 2.6% in Group B ( P .024), and in patients with intraoperative high-flow leaks, the incidences were 11.7% and 3.1%, respectively ( P .048). L-PRF reduced postoperative CSF leak by 76% in cases with intraoperative CSF leak (relative risk 0.24, 95% CI 0.06-0.87) and by 73% of patients with high-flow leak (relative risk 0.27, 95% CI 0.07-0.99). In patients undergoing surgery for diagnoses other than adenomas, there were no cases of postoperative leak in Group B, whereas in Group A occurred in 13.4% of those with intraoperative leaks ( P .047) and 15.8% with high-flow intraoperative leaks ( P .033). No significant differences were found in patients with pituitary adenoma. Meningitis occurred in 0.97% in Group A vs 2.16% in Group B ( P .639), without differences between subgroups.

CONCLUSION

L-PRF reduced the rate of postoperative CSF leaks in patients with intraoperative leaks, without differences on postoperative meningitis.

Effect of advanced and injectable platelet-rich fibrins against Aggregatibacter actinomycetemcomitans in subjects with or without periodontal diseases

Background/purpose: Data for comparing effects of advanced platelet-rich fibrin (A-PRF+) and injectable platelet-rich fibrin (i-PRF) against Aggregatibacter actinomycetemcomitans (Aa) in subjects with differently periodontal conditions are scarce. This study aimed to compare the antimicrobial capacity of A-PRF+ and i-PRF obtained from subjects with or without periodontal diseases against the pathogenic bacteria Aa.

Materials and methods

The number of red blood cells, platelets, and white blood cells on the blood samples of 60 individuals, including healthy subjects (n = 20), patients with gingivitis (n = 20), and patients with periodontitis (n = 20), were analyzed before preparing A-PRF+ and i-PRF. In addition, the in vitro antibacterial effect of the two platelet concentrates was evaluated by using the agar diffusion test and a minimum inhibitory concentration (MIC) experiment.

Results

I-PRF exhibited a significantly better antibacterial effect than A-PRF+ within the gingivitis and periodontitis groups, with a more expansive zone of inhibition and a lower MIC. Among the studied groups, the A-PRF+ and i-PRF collected from the periodontitis group inhibited Aa significantly more compared with the gingivitis and healthy groups.

Conclusion

Although both A-PRF+ and i-PRF exhibited an antibacterial effect against Aa through the zone of inhibition and MIC tests, in the gingivitis and periodontitis groups, i-PRF exhibited better antibacterial activity than A-PRF+, and PRF products from the periodontitis group had greater effects against Aa than PRF products from the two other groups.

Effect of platelet-rich fibrin (PRF) membranes on the healing of infected skin wounds

Tissue engineering focuses on wound healing and tissue regeneration. Platelet-rich fibrin (PRF) is a fibrin matrix containing cytokines, growth factors and cells that are gradually released into the wound over time. This study aimed to evaluate the effect of PRF membranes on wound repair and microbial control in infected wounds. Skin wounds were performed on the dorsum of rats using a 6 mm diameter metal punch. The defects were randomly assigned into four groups (n = 12/each) accordingly to the treatment: G1, noninfected wound filled only with clot; G2, noninfected wound with PRF; G3, infected wound (S. aureus) without PRF; G4, infected wound (S. aureus) with PRF. After 7 and 14 days, macroscopic and histological analyses of the wounds were performed. Furthermore, the quantification of β-defensin in PRF was measured by ELISA. At 14 days, the groups with PRF (G2 and G4) had wound sizes significantly smaller than the original defects (6 mm) (p < 0.05) and significantly smaller than those not treated with PRF, in both the infected and noninfected groups (p < 0.05). Furthermore, the groups with infected wounds (G3 and G4) demonstrated a significantly lower inflammation score in the PRF group than in the noninfected groups (p < 0.05). In vitro analysis of β-defensin was performed in all PRF membrane groups, and the median value was 1.444 pg/mL. PRF in the wounds of both control and infected rats played an important role in the modulation of tissue healing, most notably in infected sites.

Fibrin clot and Leukocyte-rich platelet-rich fibrin show similar release kinetics and amount of growth factors: a pilot study

BACKGROUND

In knee arthroscopic surgery, fibrin clot (FC) and leukocyte-rich platelet-rich fibrin (L-PRF) may be used in augmentation for meniscal repair. Studies have investigated growth factors released from FC and L-PRF; however, it is difficult to compare FC and L-PRF between different studies. Direct comparison of growth factors that may support meniscal healing released from FC and L-PRF may be beneficial in deciding whether to use FC or L-PRF. If no significant difference is seen, the surgeon may decide to use FC which is easier to prepare compared to L-PRF. The purpose of this pilot study is to investigate the release amount and pattern of basic fibroblast growth factor (bFGF), platelet-derived growth factor AB (PDGF-AB), transforming growth factor β1 (TGF-β1), vascular endothelial growth factor (VEGF), and stromal cell-derived factor 1 (SDF-1) from FC and L-PRF.

METHOD

Twenty milliliters (ml) of whole blood was collected from each of the four volunteers. Ten milliliters of whole blood was allocated for preparation of FC and 10 ml for L-PRF. FC and L-PRF were separately placed in 5 ml of culture media. Five milliliters of the culture media was sampled and refilled at 15 min, 1 day, 3 days, 1 week and 2 weeks. The collected culture was used to quantify bFGF, PDGF-AB, TGF-β1, VEGF, and SDF-1 release by Enzyme-linked immune-sorbent assay (ELISA). Mann-Whitney U test was performed to assess significance of differences in amount of each growth factor released between FC and L-PRF. Significance was accepted at P value less than 0.05.

RESULTS

At two weeks, the cumulative release of TGF-β1 was the highest among all the growth factors in both FC and L-PRF (FC:19,738.21 pg/ml, L-PRF: 16,229.79 pg/ml). PDGF-AB (FC: 2328 pg/ml, L-PRF 1513.57 pg/ml) had the second largest amount, followed by VEGF (FC: 702.06 pg/ml, L-PRF 595.99 pg/ml) and bFGF (FC: 23.48 pg/ml, L-PRF 18.2 pg/ml), which order was also common in both FC and L-PRF. No significant difference in final release amount and pattern was seen between FC and L-PRF.

CONCLUSION

The current pilot study showed that cumulative release amount and release pattern of PDGF-AB, VEGF, TGF-β1, and bFGF did not significantly differ between FC and L-PRF during the two weeks of observation.

Can platelet-rich fibrin act as a natural carrier for antibiotics delivery? A proof-of-concept study for oral surgical procedures

OBJECTIVES

Evaluate the role of platelet-rich fibrin (PRF) as a natural carrier for antibiotics delivery through the analysis of drug release and antimicrobial activity.

MATERIALS AND METHODS

PRF was prepared according to the L-PRF (leukocyte- and platelet-rich fibrin) protocol. One tube was used as control (without drug), while an increasing amount of gentamicin (0.25 mg, G1; 0.5 mg, G2; 0.75 mg, G3; 1 mg, G4), linezolid (0.5 mg, L1; 1 mg, L2; 1.5 mg, L3; 2 mg, L4), vancomycin (1.25 mg, V1; 2.5 mg, V2; 3.75 mg, V3; 5 mg, V4) was added to the other tubes. At different times the supernatant was collected and analyzed. Strains of E. coli, P. aeruginosa, S. mitis, H. influenzae, S. pneumoniae, S. aureus were used to assess the antimicrobial effect of PRF membranes prepared with the same antibiotics and compared to control PRF.

RESULTS

Vancomycin interfered with PRF formation. Gentamicin and linezolid did not change the physical properties of PRF and were released from membranes in the time intervals examined. The inhibition area analysis showed that control PRF had slight antibacterial activity against all tested microorganisms. Gentamicin-PRF had a massive antibacterial activity against all tested microorganisms. Results were similar for linezolid-PRF, except for its antibacterial activity against E. coli and P. aeruginosa that was comparable to control PRF.

CONCLUSIONS

PRF loaded with antibiotics allowed the release of antimicrobial drugs in an effective concentration. Using PRF loaded with antibiotics after oral surgery may reduce the risk of post-operative infection, replace or enhance systemic antibiotic therapy while preserving the healing properties of PRF. Further studies are needed to prove that PRF loaded with antibiotics represents a topical antibiotic delivery tool for oral surgical procedures.

Platelet-rich fibrin combined with a particulate bone substitute versus guided bone regeneration in the damaged extraction socket: An in vivo study

AIM

It has been proposed that platelet-rich fibrin (PRF) can be used to support bone regeneration during alveolar ridge augmentation. The aim of this study was to determine whether an approach utilizing PRF provides similar performance to the established guided bone regeneration (GBR) procedure.

MATERIALS AND METHODS

Two-wall defects were surgically created in beagle dogs and treated in three experimental groups: (i) a sticky bone (SB) substitute prepared using liquid PRF and deproteinized porcine bone mineral (DPBM); (ii) SB covered with solid PRF compressed into a membrane; and (iii) GBR performed using DPBM covered by a collagen membrane. Quantitative reverse-transcription polymerase chain reaction was applied to the specimen after 1 week of healing, and microcomputed tomography (micro-CT) and histological outcomes were analysed after 8 weeks of healing.

RESULTS

Compared with GBR, PRF resulted in a moderate increase in the expression levels of osteoblast and osteoclast markers, osteocalcin, and calcitonin receptor. Moreover, PRF modestly increased angiogenesis and the inflammation markers vascular endothelial growth factor (VEGF) and IL-6. Micro-CT and histological analyses confirmed the expected increased alveolar ridge area, with no significant differences between the three groups. Consistently, graft consolidation, as indicated by new bone formation at the defect site, did not differ significantly between groups.

CONCLUSIONS

The present results demonstrate that PRF-based approaches perform comparably to the established GBR procedure in terms of the consolidation of DPBM in two-wall alveolar defects.

Platelets, Protean Cells with All-Around Functions and Multifaceted Pharmacological Applications

Platelets, traditionally known for their roles in hemostasis and coagulation, are the most prevalent blood component after erythrocytes (150,000-400,000 platelets/μL in healthy humans). However, only 10,000 platelets/μL are needed for vessel wall repair and wound healing. Increased knowledge of the platelet's role in hemostasis has led to many advances in understanding that they are crucial mediators in many other physiological processes, such as innate and adaptive immunity. Due to their multiple functions, platelet dysfunction is involved not only in thrombosis, mediating myocardial infarction, stroke, and venous thromboembolism, but also in several other disorders, such as tumors, autoimmune diseases, and neurodegenerative diseases. On the other hand, thanks to their multiple functions, nowadays platelets are therapeutic targets in different pathologies, in addition to atherothrombotic diseases; they can be used as an innovative drug delivery system, and their derivatives, such as platelet lysates and platelet extracellular vesicles (pEVs), can be useful in regenerative medicine and many other fields. The protean role of platelets, from the name of Proteus, a Greek mythological divinity who could take on different shapes or aspects, is precisely the focus of this review.

Evaluation of low-level laser therapy and platelet-rich fibrin on donor site healing after vascularized interpositional periosteal connective tissue flap: a randomized clinical study

AIM

To evaluate the effectiveness of platelet-rich fibrin (PRF) and low-level laser therapy (LLLT) on donor site healing after vascularized interpositional periosteal connective tissue (VIP-CT) flap.

MATERIALS AND METHODS

For the present clinical study, the selected patients requiring VIP-CT flap were randomly assigned into either of the two treatment groups (VIP-CT/PRF and VIP-CT/LLLT). For VIP-CT/PRF, palatal donor site treated with platelet-rich fibrin (PRF, n = 15) after harvesting VIP-CT flap; and for VIP-CT/LLLT, palatal donor site treated with low-level laser therapy (LLLT, n = 16) after harvesting VIP-CT flap.

RESULTS

The mean thickness of palatal mucosa at surgical site was increased from 2.91 ± 0.65 to 2.93 ± 0.55 mm after 1 week and to 3.02 ± 0.55 mm after 12 weeks while in PRF-treated site, while in LLLT-treated sites, palatal mucosal thickness decreased after 1 week from 3.35 ± 0.56 mm to 1.83 ± 0.48 mm and then increase to 3.35 ± 0.55 mm after 12 weeks, and the mean difference was significantly higher for PRF-treated group compared to LLLT-treated group. In regard to contour, absence of hypertrophic tissue was observed in VIP-CT/LLLT compared with VIP-CT/PRF group (40% of patients, p = 0.003) at 4 weeks. "Absence" of pain and burning sensation were observed as early as at 1 week in LLLT-treated palatal donor sites compared to PRF-treated palatal donor site after VIP-CT. Improvement in post-surgical complications like ecchymosis, tissue necrosis, swelling, and infection were observed almost 100% at 4 weeks in both the groups.

CONCLUSION

Favourable clinical outcomes in terms of tissue thickness, consistency, color, contour, scar, pain, and burning sensation and patient comfort were obtained in both LLLT- and PRF-treated donor palatal sites at 12 weeks. Non-significant increase in tissue thickness was observed compared to baseline in PRF-treated donor sites at 12 weeks compared to LLLT-treated donor sites.

CLINICAL SIGNIFICANCE

Both low-level laser therapy (LLLT) using 940 nm wavelength and autologous platelet-rich fibrin (PRF) can be utilized to enhance early wound healing and reduce the palatal donor site morbidity.

Failure to disclose industry funding impacts outcomes in randomized controlled trials of platelet-rich plasma

PURPOSE

Platelet-rich plasma (PRP) represents a highly profitable biological therapy. Platelet-rich plasma is widely used to treat musculoskeletal disorders despite mixed evidence of its efficacy. As evidenced by literature from other domains, industry funding may influence the results of clinical trials. The objective of the current study was to determine the association between industry funding and positive results for randomized controlled trials (RCTs) assessing the efficacy of PRP in musculoskeletal disorders.

METHODS

A search of four databases was conducted. Included studies were RCTs comparing PRP to any non-PRP comparator in adults (18 years old or over) with musculoskeletal disorders and had full text available in English. Studies were excluded if they were published before 2016 or were non-human trials. A multivariate binomial logistic regression model was created to explore predictors of statistically significant findings. Covariates included the presence of industry funding, sample size, and length of study follow-up. 1440 records were screened with 87 trials included in the final analysis.

RESULTS

Of the 87 studies, 61 (70%) reported a statistically significant primary outcome. The presence of industry funding was not predictive of a statistically significant primary outcome [OR = 0.36, 95% CI 0.096-1.36, (n.s.)]. Studies that did not state whether industry funding was present had a higher chance of reporting a statistically significant primary outcome (OR = 3.61, 95% CI 1.1-11.9, p = 0.035). Sample size and length of follow-up were not predictive of a statistically significant primary outcome.

CONCLUSION

The results of the current study conclude that industry funding had no impact on the reporting of positive results for RCTs investigating PRP in musculoskeletal disorders. However, not disclosing sources of funding was associated with a higher likelihood of reporting positive results. The results of trials that fail to disclose funding sources should be interpreted with caution in the PRP literature.

LEVEL OF EVIDENCE

I.

An umbrella review of the use of platelet-rich plasma in the treatment of androgenetic alopecia

OBJECTIVE

To evaluate the efficacy of platelet-rich plasma (PRP) in the treatment of androgenetic alopecia, as well as establish an effective treatment protocol and optimal PRP preparation procedure.

METHODS

We searched the PubMed, Scopus, Embase, Cochrane, CNKI, and Wanfang databases from inception to October 29, 2021, using PROSPERO's International Prospective Register of Systematic Reviews (registration ID: CRD42022295921).

RESULTS

The original literature search revealed 215 reviews; after duplication removal, 89 papers were eliminated, 95 were eliminated after reading the titles and abstracts, and eventually, 28 articles were included after reading the complete text.

CONCLUSIONS

PRP treatment for androgenetic alopecia is effective, and we recommend the following: (1) a PRP volume of at least 0.05 ml/cm² , preferably 0.1 ml/cm² ; (2) at least three consecutive treatments at an interval of 1 month; (3) intensive therapy is beneficial and can be provided from 3 to 6 months after continuous treatment; (4) objective indicators such as hair diameter, hair count; (5) long-term follow-up.

The Efficacy of Platelet-Rich Plasma Injection Therapy in the Treatment of Patients with Achilles Tendinopathy: A Systematic Review and Meta-Analysis

BACKGROUND

Over the past few years, many studies have been conducted to evaluate the effectiveness of platelet-rich plasma (PRP) in treating musculoskeletal conditions. However, there is controversy about its benefits for patients with Achilles tendinopathy.

OBJECTIVE

This study aimed to investigate whether platelet-rich plasma injections can improve outcomes in patients with Achilles tendinopathy.

METHODS

A comprehensive literature search was conducted in PubMed, Embase, Cochrane Library, Web of Science, China Biomedical CD-ROM, and Chinese Science and Technology Journal databases to identify randomised controlled clinical trials that compared the efficacy of PRP injection in patients with Achilles tendinopathy (AT) versus placebo, published between 1 January 1966 and 1 December 2022. Review Manager 5.4.1 software was used for the statistical analysis, and the Jadad score was used to assess the included literature. Only 8 of the 288 articles found met the inclusion criteria.

RESULTS

Our work suggests that: The PRP treatment group had a slightly higher VISA-A score than the placebo group at 6 weeks [MD = 1.92, 95% CI (-0.54, 4.38), I² = 34%], at 12 weeks [MD = 0.20, 95% CI (-2.65 3.05), I² = 60%], and 24 weeks [MD = 2.75, 95% CI (-2.76, 8.26), I² = 87%]). However, the difference was not statistically significant. The Achilles tendon thickness was higher at 12 weeks of treatment in the PRP treatment group compared to the control group [MD = 0.34, 95% CI (-0.04, 0.71), p = 0.08], but the difference was not statistically significant. The VAS-improvement results showed no significant difference at 6 and 24 weeks between the two groups, respectively (MD = 6.75, 95% CI = (-6.12, 19.62), I² = 69%, p = 0.30), and (MD = 10.46, 95% CI = (-2.44 to 23.37), I² = 69%, p = 0.11). However, at 12 weeks of treatment, the PRP injection group showed a substantial VAS improvement compared to the control group (MD = 11.30, 95% CI = (7.33 to 15.27), I² = 0%, p < 0.00001). The difference was statistically significant. The return to exercise rate results showed a higher return to exercise rate in the PRP treatment group than the placebo group [RR = 1.11, 95% CI (0.87, 1.42), p = 0.40]; the difference was not statistically significant.

CONCLUSION

There is no proof that PRP injections can enhance patient functional and clinical outcomes for Achilles tendinopathy. Augmenting the frequency of PRP injections may boost the outcomes, and additionally, more rigorous designs and standardised clinical randomised controlled trials are needed to produce more reliable and accurate results.

Evaluation of Platelet-Rich Plasma by means of PRGF®-Endoret® protocol in leukemia cats: PDGF-BB and TGF-ß1 valuation

Introduction

Feline leukemia virus (FeLV) is a chronic disease that leads to the weakening of a cat's immune system. Platelet-rich plasma (PRP) offers therapeutic effects for multiple diseases, the use of PRP and growth factors (GFs) determination could be an alternative treatment to improve the quality of life in these patients. The objectives of this study were to determine and compare the concentration of platelets (PLTs), red blood cells (RBCs) and white blood cells (WBCs) between samples of whole blood (WB), PRP and platelet-poor plasma (PPP) fractions, and to evaluate the concentration of platelet-derived growth factor BB (PDGF-BB) and transforming growth factor β1 (TGF-β1) in both fractions in FeLV cats using a PRGF^®-Endoret^® protocol previously standardized in this species.

Methods

WB was collected from 11 asymptomatic FeLV-positive cats. PRP and PPP was obtained following PRGF^®-Endoret^® technology according to centrifugation at 265 g for 10 min. Cellular components, RBCs, WBCs, PLTs, and the PDGF-BB and TGF-β1 concentrations in PRP and PPP fractions were determined.

Results

PLT in the PRP fraction was statistically higher than WB and PPP fraction, with no statistical differences between WB and PPP. PLT concentration increased 1.4 times in PRP fraction compared to WB. Mean platelet volume (MPV) did not differ significantly between the WB, PRP, and PPP fractions. Compared to WB, the absolute numbers of RBCs and WBCs were decreased by 99% and more than 95% in the PRP and PPP fractions, respectively. TGF-ß1 concentrations increased in PRP vs. PPP, with no changes in PDGF-BB.

Discussion

Based on the degree of PLT enrichment and the absence of RBCs and WBCs, this blood product could be classified as a Pure Platelet-Rich Plasma (P-PRP). The presence of GFs in PRP and PPP samples suggests that the PRGF^®-Endoret^® methodology is suitable for obtaining PRP in FeLV cats, despite future studies are necessary to optimize the technique, standardize the results and assess clinical efficacy.

Characterization and Safety Profile of a New Combined Advanced Therapeutic Medical Product Platelet Lysate-Based Fibrin Hydrogel for Mesenchymal Stromal Cell Local Delivery in Regenerative Medicine

Adipose-derived mesenchymal stromal cells (ASC) transplant to recover the optimal tissue structure/function relationship is a promising strategy to regenerate tissue lesions. Because filling local tissue defects by injection alone is often challenging, designing adequate cell carriers with suitable characteristics is critical for in situ ASC delivery. The aim of this study was to optimize the generation phase of a platelet-lysate-based fibrin hydrogel (PLFH) as a proper carrier for in situ ASC implantation and (1) to investigate in vitro PLFH biomechanical properties, cell viability, proliferation and migration sustainability, and (2) to comprehensively assess the local in vivo PLFH/ASC safety profile (local tolerance, ASC fate, biodistribution and toxicity). We first defined the experimental conditions to enhance physicochemical properties and microscopic features of PLFH as an adequate ASC vehicle. When ASC were mixed with PLFH, in vitro assays exhibited hydrogel supporting cell migration, viability and proliferation. In vivo local subcutaneous and subgingival PLFH/ASC administration in nude mice allowed us to generate biosafety data, including biodegradability, tolerance, ASC fate and engraftment, and the absence of biodistribution and toxicity to non-target tissues. Our data strongly suggest that this novel combined ATMP for in situ administration is safe with an efficient local ASC engraftment, supporting the further development for human clinical cell therapy.

Clinical Efficacy of Intra-Articular Injection with P-PRP Versus that of L-PRP in Treating Knee Cartilage Lesion: A Randomized Controlled Trial

OBJECTIVE

Platelet-rich plasma（PRP), with different concentration of leukocytes, may lead to varying effects in the treatment of cartilage lesions. So far, current research has not shown enough evidence on this. To evaluate the clinical efficacy and safety of intra-articular injection with pure platelet-rich plasma (P-PRP) versus those of leukocyte platelet-rich plasma (L-PRP) in treating knee cartilage lesions, we conducted a double-blind, randomized controlled clinical trial with a larger sample and longer follow-up period.

METHODS

From October 2019 to October 2020, 95 patients were invited to participate in our study, and 60 (63.2%) were randomized to P-PRP (n = 30) or L-PRP (n = 30) groups. Patients from the two groups were treated with knee intra-articular injections of P-PRP or L-PRP. Visual analog scale (VAS) and Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores were assessed using an unpaired t-test for independent samples preoperatively and at 6 weeks, 12 weeks, 6 months, and 12 months after intervention.

RESULTS

We followed up 27 cases in the P-PRP group and 26 cases in the L-PRP group. No significant differences in VAS and WOMAC scores were found between the two groups before the intervention (p > 0.05). The WOMAC Pain and VAS-Motions scores of the P-PRP group were significantly lower than those of the L-PRP group at 6 weeks after the intervention (p < 0.05). While the long-term clinical efficacy of both injections was similar and weakened after 12 months, more adverse events were found in the L-PRP group.

CONCLUSIONS

The short-term results demonstrate a positive effect in reducing pain and improving function in patients with knee cartilage lesions in the two groups. While the P-PRP injection showed better clinical efficacy in the early phase of postoperative rehabilitation and resulted in fewer adverse events, long-term follow-up showed similar and weakened efficacy after 12 months.

TRIAL REGISTRATION

ChiCTR1900026365. Registered on October 3, 2019, http://www.chictr.org.cn/showproj.aspx?proj=43911.

The proteins derived from platelet-rich plasma improve the endothelialization and vascularization of small diameter vascular grafts

Vascular transplantation has become an ideal substitute for heart and peripheral vascular bypass therapy and tissue-engineered vascular grafts (TEVGs) present an attractive potential solution for vascular surgery. However, small diameter (Ф < 6 mm) vascular do not have ideal TEVGs for clinical use. Platelet-rich plasma (PRP), a key source of bioactive molecules, has been confirmed to promote tissue repair and regeneration. In this study, we prepared PRP-loaded TEVGs (PRP-TEVGs) by electrospinning, investigated the characterization of TEVGs, and verified the effect of PRP-TEVGs in vivo and in vitro experiments. The results suggested that PRP-TEVGs had good biocompatibility, released growth factors stably, promoted cell proliferation and migration significantly, up-regulated the expression of endothelial NO synthase (eNOS) in functional vascular endothelial cells (VECs), and maintained the stability of the endothelial structure. In vivo experiments suggest that PRP can promote rapid endothelialization and reconstruction of TEVGs. Overall, this finding indicated that PRP could promote the rapid vascular endothelialization of small-diameter TEVGs by improving contractile vascular smooth muscle cells (VSMCs) regeneration, and maintaining the integrity and functionality of VECs.

The Effect of PRP Augmentation of Arthroscopic Repairs of Shoulder Rotator Cuff Tears on Postoperative Clinical Scores and Retear Rates: A Systematic Review and Meta-Analysis

The aim of this review and meta-analysis is to assess recent clinical trials concerning the combination of operative treatment of rotator cuff tears and the administration of PRP and its effect on clinical scores and postoperative retear rates. The trials were used to compare the combination of PRP treatment and arthroscopic rotator cuff repair to arthroscopy alone. Twenty-five clinical trials were reviewed. A risk-of-bias assessment was made for all randomized clinical trials included, using the Cochrane collaboration’s tool as well as a quality assessment for all non-randomized studies utilizing the Newcastle−Ottawa scale. The PRP-treated patients showed statistically significant improvement postoperatively compared to control groups concerning the Constant−Murley (mean difference 2.46, 95% CI 1.4−3.52, p < 0.00001), SST (mean difference 0.32, 95% CI 0.02−0.63, p = 0.04), and UCLA (mean difference 0.82, 95% CI 0.23−1.43, p = 0.07) scores. A statistically significant decrease of retear rates in the PRP-treated patients, with a risk ratio of 0.78 (95% CI 0.65−0.94, p = 0.01), was found. We believe that the results presented have positive aspects, especially concerning the retear risk, but are yet inconclusive concerning clinical results such as shoulder pain and function.

Leukocyte-Rich vs. Leukocyte-Poor Platelet-Rich Plasma for the Treatment of Knee Osteoarthritis

Knee osteoarthritis (OA) is a well-established form of OA and accounts for nearly 4/5 of global OA burden […].

Can Our Blood Help Ensure Antimicrobial and Anti-Inflammatory Properties in Oral and Maxillofacial Surgery?

In recent decades, the potential of PRF has been extensively studied. The number of studies about PRF has increased three times since the year 2012, but the full spectrum of its fundamental properties, such as antimicrobial and anti-inflammatory activity, is not clearly described. In oral and maxillofacial surgery, PRF is described in alveolar ridge preservation, orthognathic surgery, cleft lip and palate surgery, maxillary sinus augmentation, and dental implant placement as demonstrating favorable results and its clinical advantages. The structural complexity, inhomogeneous nature, and clotting ability of PRF make its antimicrobial effect evaluation complicated. Nevertheless, most of the used antimicrobial testing methods are based on antibacterial agent diffusion ability in culture media. Because the oral and maxillofacial region is the most frequent area of PRF application, its antimicrobial activity evaluation also prevails in the oral microbiome. PRF's biological potential is highly dependent on the specific preparation protocol and methodology used; it should be carefully prepared and kept under proper conditions to keep cellular content alive. PRF's influence on living cells demonstrates a stimulating effect on bone regeneration, and an angiogenetic effect, and it provides anti-inflammatory activity. According to analyzed studies, PRF demonstrated success in oral and maxillofacial surgery in various methods of application. Antibacterial and anti-inflammatory properties were proven by antibacterial activity against different bacterial species, sustained growth factor, sustained release, and cell activity on the material application. Accurately and correctly prepared PRF can ensure antibacterial and anti-inflammatory properties, and it can be a beneficial clinical tool in oral and maxillofacial surgery.