The healing effects of autologous platelet gel on acute human skin wounds

Development and Characterization of a Novel Composite Hydrogel Biomaterial for Improved Mucoperiosteal Wound Repair

Mucoperiosteal wound healing, as it occurs after pediatric cleft palate surgery, can be challenging due to the limitations of current treatments such as tissue flaps secured with sutures and fibrin glue. In this study, we characterized the in vitro performance of a novel composite hydrogel biomaterial designed to be employed as an in situ wound filler and enhance mucoperiosteal wound healing. We evaluated a range of photopolymerizable formulations containing methacrylated gelatin (GelMA), glycol chitosan, and bioglass microparticles. Our aim was to identify one or more formulations with an appropriate balance of properties against a set of functional requirements that we established for this application. To test the formulations against these criteria, we measured photopolymerization kinetics, mechanical properties, degradation rate, in vitro biocompatibility, and ex vivo tissue adhesion. All formulations polymerized in less than 90 s using violet light. In addition, we found that GelMA-based hydrogels were more adhesive to mucoperiosteal tissue than clinical standard fibrin glue. Inclusion of small amounts of bioglass in the formulation increased mechanical compatibility with mucoperiosteal tissue, enhanced cytoconductivity, and promoted cell proliferation. Taken together, our results support the suitability of these photopolymerized composite hydrogels as in situ mucoperiosteal wound fillers. Overall, this study lays the groundwork for investigating the in vivo, pre-clinical effectiveness of these composite hydrogels in improving mucoperiosteal wound healing outcomes.

The emerging role of biostimulators as an adjunct in facial rejuvenation: A systematic review

INTRODUCTION

Facial aging has long been an area of focus in esthetic surgery. It is the consequence of physiologic and environmental factors, with a trend toward non-surgical modalities. Although volume augmentation has long been a focus of non-surgical facial rejuvenation, there is emerging interest in the use of biostimulators to induce physiologic changes in the skin. This article aimed to provide an overview of this class of therapies.

METHODS

A systematic review regarding the clinical use of biostimulatory agents including platelet-rich plasma (PRP), platelet-rich fibrin (PRF), poly-L-lactic acid (PLLA) and calcium hydroxylapatite (CaHA) in facial rejuvenation was performed using PubMed databases. The protocol was developed following the preferred reporting for items for systematic reviews-protocols guidelines. Included studies matched predetermined criteria according to the employed intervention and outcomes.

RESULTS

The systematic review was performed in September 2023, with the primary search yielding 464 articles. Abstract review resulted in 73 articles of potential relevance. Comprehensive review of the articles and manual reference checks were performed, independently, by 2 authors. This yielded a total of 45 articles that met the inclusion criteria.

CONCLUSIONS

There is an increasing role for non-surgical modalities in facial rejuvenation. Biostimulatory agents may be used as an alternative, or act as an adjunct, to other non-surgical modalities. These agents induce physiologic changes that mitigate facial aging. There is limited, quantifiable data, which fully illustrate the effect in these products. Although these agents are known to illicit inflammatory changes, more controlled studies are needed to better elucidate the biostimulatory capacity of such non-surgical treatments.

Current and Future Developments in Wound Healing

Poor wound healing on the face and neck can lead to significant morbidity and dissatisfaction in facial plastic surgery. With current advances in wound healing management and commercially available biologic and tissue-engineered products, there are several options available to optimize acute wound healing and treat delayed or chronic wounds. This article summarizes some of the key principals and recent developments in wound healing research in addition to potential future advancements in the field of soft tissue wound healing.

Role for platelet rich plasma as an adjuvant therapy in wound healing and burns

Background

Platelet rich plasma (PRP) contains high concentrations of growth factors. Intuitively, these were thought to be of potential benefit in healing of chronic wounds, skin grafts and graft donor sites. This was echoed in retrospective studies and an individual case basis but had not been randomized.

Methods

A systematic search was carried out by two individuals, independently, on the MEDLINE, EMBASE and COCHRANE databases, according to PRISMA guidelines. All data analysis and statistics was pooled and analysed using the Cochrane RevMan Software.

Results

Split thickness grafts have been described by numerous authors, but PRP use did not offer a significant advantage in graft take in pooled results (MD 5.83, 95% CI − 0.69 to 12.25, random-effects, p = 0.08). The analysis of included randomized controlled trials has shown favourable split-thickness skin graft donor site healing in the PRP group (MD − 5.55, 95% CI − 7.40 to − 3.69, random-effects, p =  < 0.00001) compared to the control group. For carpal tunnel syndrome, the pooled results showed no difference in functional scores vs steroid injections (SMD − 0.68, 95% CI − 1.47 to 0.10, randomeffects, p = 0.09) or indeed splinting groups.

Conclusions

With the current body of evidence, we conclude that the use of PRP as an adjuvant therapy in skin grafts, burns, carpal tunnel surgery or scars cannot be rationalised. A potential use of PRP is in donor site management but the cost of this would be difficult to justify.

Level of evidence: Not ratable.

A Prospective Multicenter Study to Evaluate the Safety and Efficacy of the Topical Application of MYOWNN™, an Autologous Growth Factor Concentrate (AGFC) Serum, in Anti-Aging

Background

Growth factors from platelets have been emerging as a revolutionary treatment with the ability to induce cell growth in the skin, which results in retarding and reversing the aging process. Platelet-rich plasma (PRP) allows for greater release of growth factors and biologically active proteins, which in turn activates the cascade of stimulation of neoangiogenesis and collagen production. PRP is used in anti-aging and facial skin rejuvenation in the form of dermal injections and topical application during micro-needling. This study was conducted to assess the safety and efficacy of a topically applied face serum, MYOWNN™ (Wockhardt Ltd., Mumbai, India). MYOWNN™ is an autologous growth factor concentrate that has been made into a topical face serum.

Methods

Male and female subjects in the age group between 30 and 55 years (both inclusive) with Fitzpatrick skin type III-V who had not taken any oral or topical treatments for at least four weeks before and any platelet-rich plasma (PRP) based facial treatment (injections) at least six months before the study entry were included. MYOWNN™ serum was applied on the face once daily at night, approximately 30 minutes before sleeping preferably, for a total duration of five months. Six parameters, i.e. spots, pores, wrinkles, texture, moisture, and pigmentation, were evaluated at regular intervals with Visage-LS (dermaindia®, Tamil Nadu, India), a face analysis system that gives the live status of these six parameters and is an advanced live status skin detection equipment together with shooting, analyzing, and displaying functions, as well as the subjective analysis, was performed by subjects and physicians using different globally accepted scales like physician’s global aesthetic improvement scale (PGAIS), subject’s global aesthetic improvement scale (SGAIS), subject satisfaction score (SSS), and wrinkle severity rating scale (WSRS). For analysis, a mixed model for repeated measures was used. The model had change from baseline as the dependent variable visit as a factor and baseline assessment result as a covariate. All primary and secondary efficacy endpoints were analyzed using Modified Intent-to-Treat (mITT) populations.

Results

Improvement in an average of six anti-aging parameters was observed as early as three months while statistically significant improvement was observed by the end of five months of application. A statistically significant improvement in wrinkles was observed by the end of three months of the application itself. There were no product-related adverse events reported.

Conclusions

Five months of application of MYOWNN™ serum showed a statistically significant improvement in an average of six parameters of anti-aging and face rejuvenation with a p-value of 0.0150 (<5% level of significance (i.e. 0.05) and was also well-tolerated.

Characterization of a Human Platelet Lysate-Loaded Keratin Hydrogel for Wound Healing Applications In Vitro

One of the promising approaches to facilitate healing and regenerative capacity includes the application of growth-factor-loaded biomaterials. Human platelet lysate (hPL) derived from platelet-rich plasma through a freeze-thaw process has been used as a growth factor rich therapeutic in many regenerative applications. To provide sustained local delivery of the hPL-derived growth factors such as epidermal growth factor (EGF), the hPL can be loaded into biomaterials that do not degrade rapidly in vivo. Keratin (KSO), a strong filamentous protein found in human hair, when formulated as a hydrogel, is shown to sustain the release of drugs and promote wound healing. In the current study, we created a KSO biomaterial that spontaneously forms a hydrogel when rehydrated with hPL that is capable of controlled and sustained release of pro-regenerative molecules. Our study demonstrates that the release of hPL is controlled by changing the KSO hydrogel and hPL-loading concentrations, with hPL loading concentrations having a greater effect in changing release profiles. In addition, the 15% KSO concentration proved to form a stable hydrogel, and supported cell proliferation over 3 days without cytotoxic effects in vitro. The hPL-loaded keratin hydrogels show promise in potential applications for wound healing with the sustained release of pro-regenerative growth factors with easy tailoring of hydrogel properties.

Intra-individual Right-Left Comparative Study of Combined Therapy of Intramatricial Triamcinolone and Platelet-Rich Plasma vs. Intramatricial Triamcinolone Only in Lichen Planus-Associated Nail Dystrophy

Background

While intramatricial triamcinolone is the most commonly used treatment option for onychodystrophy due to lichen planus, the role of platelet-rich plasma (PRP) in the treatment of onychodystrophy is not established. So we combined the two treatment modalities to assess the synergistic action on nail dystrophy.

Aims and Objectives

The aim of this article is to compare the effect of combination of intramatricial triamcinolone and PRP vs. intramatricial triamcinolone alone in the treatment of onychodystrophy.

Materials and Methods

This study was done in 26 and 25 pairs of symmetrical dystrophic nails in hands and feet, respectively. The patients received intramatricial injection of triamcinolone and PRP on one side of finger and toe nails and triamcinolone on the contralateral side.

Results

Statistically significant improvements in grades of dystrophy according to the Nail Dystrophy Grading System (NDGS) in the finger and toe nails treated with combined therapy were obtained (P < 0.001 and = 0.002, respectively). According to the physician global assessment, response to combination therapy was statistically significant between the two comparison groups of finger and toe nails (P = 0.001 and = 0.004, respectively). Similarly, according to the patient satisfaction score, statistically significant difference was found between the comparison groups of combination therapy and single therapy (P < 0.001).

Conclusion

Addition of PRP significantly improved the nail quality. Intramatricial PRP is a safe and effective therapeutic modality in refractory nail dystrophies.

Accelerated complete human skin architecture restoration after wounding by nanogenerator-driven electrostimulation

BACKGROUND

Electrostimulation (ES) therapy for wound healing is limited in clinical use due to barriers such as cumbersome equipment and intermittent delivery of therapy.

METHODS

We adapted a human skin xenograft model that can be used to directly examine the nanogenerator-driven ES (NG-ES) effects on human skin in vivo-an essential translational step toward clinical application of the NG-ES technique for wound healing.

RESULTS

We show that NG-ES leads to rapid wound closure with complete restoration of normal skin architecture within 7 days compared to more than 30 days in the literature. NG-ES accelerates the inflammatory phase of wound healing with more rapid resolution of neutrophils and macrophages and enhances wound bed perfusion with more robust neovascularization.

CONCLUSION

Our results support the translational evaluation and optimization of the NG-ES technology to deliver convenient, efficient wound healing therapy for use in human wounds.

[Modern ulcer surgery : Invasive treatment options using the example of therapy-resistant venous leg ulcers]

The socioeconomic significance of chronic venous leg ulcers is considerable due to the high number of patients, the costs of diagnosis and therapy, the deterioration in quality of life, and the loss of working capacity during the disease. This is further increased by a progressive course and an increased tendency to recurrence. Taking these facts into account, surgical treatment options are of particular importance, especially in otherwise therapy-refractory courses. For this purpose, an extensive spectrum of surgical and new, partly not yet finally evaluated, invasive techniques are now available. Venous surgery and endovenous closure techniques are suitable for eliminating primary or secondary varicosis as a causal therapy for venous leg ulcers. Shave therapy is the method of choice in the presence of dermatolipo(fascio)sclerosis. Current long-term results show good results with cure rates of 70-80%. In individual cases, surgical techniques involving fascia cruris (faciotomy, fasciotomy) can also be used. Recurrence ulcers can often be successfully treated by repeated shave therapy, optionally with simultaneous vacuum-assisted dressing techniques or by a fasciotomy. In addition, local invasive techniques such as autologous fat tissue transplantation or autologous platelet-rich plasma can be used to promote wound healing. Thus, both surgically invasive local therapy and advanced surgery of the causes of chronic venous leg ulcers play a key role in the overall therapy concept.

Platelet-rich fibrin can accelerate the healing of common bile duct anastomosis in a rat

Objectives

This study aimed to evaluate the effect of platelet-rich fibrin (PRF) concentrate on the bile duct anastomosis healing process in rats.

Material and Methods

Thirty male Sprague Dawley (SD) rats were used for the study. The animals were allocated into three groups: Group I Control Group (n=10): Anastomosis to the common bile duct (CBD) with a stent. Group II PRF Group (n=10): Anastomosis to the CBD with a stent and covered with PRF. Group III Sham Group (n=10): Preparation of the common bile duct, no anastomosis. The animals were followed up for 1 month, then sacrificed. Study parameters were adhesions around the anastomosis, thickness of the bridging bile duct tissue over the stent, and histopathologic examination of the bridging bile duct tissue.

Results

CBD anastomosis using a stent caused severe adhesion around the anastomosis, bridging bile duct tissues were weak and histopathologically, healing was incomplete in most of the control animals. However, PRF application significantly reduced the adhesions, increased the quality of the bridging bile duct tissues, and caused complete healing histologically.

Conclusion

PRF is an autologous, easily prepared membrane. The present study findings show that PRF prevents local complications and increases the healing capacity of the bile duct after CBD anastomosis. Therefore, it might be a new treatment option for preventing complications following common bile duct anastomosis in liver transplantation patients.

Crestal bone loss around dental implants after implantation of Tricalcium phosphate and Platelet- Rich Plasma: A comparative study

BACKGROUND AND AIMS

Bone loss around dental implants is generally measured by monitoring changes in marginal bone level using radiographs. After the first year of implantation, an implant should have <0.2 mm annual loss of marginal bone level to satisfy the criteria of success. However, the success rate of dental implants depends on the amount of the crestal bone around the implants. The main aim of this study was to evaluate and compare the crestal bone loss around implants placed with particulate β-Tricalcium Phosphate Bone Graft and platelet concentrates.

METHODS

50 individuals received hundred dental implants. Each individual received one dental implant in the edentulous site filled with β-Tricalcium Phosphate Bone Graft along (β-TCP) with Platelet- Rich Plasma (PRP) (Group A) and another in edentulous site filled only with β-Tricalcium Phosphate Bone Graft (Group B) in the posterior edentulous region. All the 100 implants were prosthetically loaded after a healing period of three months. Crestal bone loss was measured on mesial, distal, buccal and lingual side of each implant using periapical radiographs 3 months, 6 months and 9 months after implant placement.

RESULTS

The average crestal bone loss 9 months after the implants placement in Group A and Group B was 2.75 mm and 2.23 mm respectively, the value being statistically significant (P < 0.05). In both Group A and Group B, the average crestal bone loss was maximum on the lingual side followed by buccal, distal and mesial sides.

CONCLUSION

β-TCP is a promising biomaterial for clinical situations requiring bone augmentation. However, the addition of PRP results in decreased bone loss around the dental implants.

Autologous platelet-rich plasma for healing chronic venous leg ulcers: Clinical efficacy and potential mechanisms

The overall quality of evidence of autologous platelet-rich plasma (PRP) for treating chronic wounds remains low. While further well-designed clinical studies are clearly required to convincingly demonstrate the efficacy of autologous PRP in improved healing of venous leg ulcers (VLUs) and other chronic wounds, there is also an increasing need to better define the underlying mechanisms of action and whether positive outcomes can be predicted based on the analysis of PRP. This brief review will discuss the current understanding of autologous PRP in VLUs and whether molecular evaluation of PRP at the time of collection could potentially be informative to clinical outcomes. Benefits of the autologous PRP treatment strategy include that PRP is easily accessible and is relatively inexpensive and safe. Better understanding of the mechanisms involved could improve treatment, enable supplementation, and/or lead to gains in product development. Analysis of PRP could also add value to future clinical trials on efficacy and potentially personalised treatment regimens.

Advances in surgical applications of growth factors for wound healing

Growth factors have recently gained clinical importance for wound management. Application of recombinant growth factors has been shown to mimic cell migration, proliferation, and differentiation in vivo, allowing for external modulation of the healing process. Perioperative drug delivery systems can enhance the biological activity of these growth factors, which have a very short in vivo half-life after topical administration. Although the basic mechanisms of these growth factors are well understood, most have yet to demonstrate a significant impact in animal studies or small-sized clinical trials. In this review, we emphasized currently approved growth factor therapies, including a sustained release system for growth factors, emerging therapies, and future research possibilities combined with surgical procedures. Approaches seeking to understand wound healing at a systemic level are currently ongoing. However, further research and consideration in surgery will be needed to provide definitive confirmation of the efficacy of growth factor therapies for intractable wounds.

Platelets and their biomimetics for regenerative medicine and cancer therapies

Platelets, circulating blood cells derived from megakaryocytes, play a key role in various physical activities, including coagulation, hemostasis, the body's innate immune response, and cancer metastasis. By taking advantage of their key traits, researchers have developed strategies to exploit platelets and platelet-mimicking nanoassemblies to treat a number of conditions, including wounds, cancers, and bacterial infections. Compared to traditional polymer, lipsosome, and inorganic nanoparticles-based delivery systems, platelets and platelet-mimicking vehicles hold many advantages. Among these are their enhanced circulation time, their large volumes and surface areas for drug loading or conjugation, and their inherent ability to target some diseases. In this review, we will highlight the recent progress made in the development of disease-targeting platelets- and platelet-mimicking-vehicles as therapeutic platforms.

Use of platelet-rich plasma to facilitate wound healing

Platelet-rich plasma (PRP) is widely used nowadays in different fields of medicine, affecting physiological processes including tissue regeneration. The use of PRP in maxillofacial surgical interventions and its efficiency in the improvement of postoperative wound healing were analysed. Patients undergoing plastic and reconstructive surgeries in the maxillofacial region were recruited: 50 patients were enrolled into a control group (received no PPRP injection) and 50 patients were enrolled into a treatment group, where PRP was applied during the surgical procedure. Evaluation of treatment outcomes was carried out by determination of IL-1β, TNFα, and IL-6 cytokines levels in the wound-drain fluid. The stages of wound healing were assessed by cytological analyses and ultrasound within a month period. The use of the PRP has substantially positive effects, contributing to the improvement of the healing process. In the treatment group, fibroblasts, macrophages, and collagen fibres appeared and their quantities increased earlier than when compared with control group patients. The concentration of IL-1β and TNFα in wound fluid on day 1 and day 5 after operation was higher for the treatment group as opposed to the control group, which was linked to the influence of PRP on inflammatory and granulation phases of the healing process. An ultrasound examination showed less oedema and infiltration in the tissues around the wound of the treatment group.

Peri-Implant Bone Loss at Implants Placed in Preserved Alveolar Bone Versus Implants Placed in Native Bone: A Retrospective Radiographic Study

Objectives

The aim of our study was to compare peri-implant bone loss at implants placed in alveolar sockets filled with a particulate allogenous bone graft (DFDBA 300-500 µm) and platelet concentrates versus at implants placed in the native bone.

Materials and Methods

A retrospective clinical study was performed. A total of 84 patients were included with 247 implants for the restoration of mono and pluri-radicular teeth: 169 implants in native bone and 78 in socket-grafted bone. The peri-implant bone loss was measured by 2 independent operators at 6 and 12 months.

Results

The overall mesial and distal peri-implant bone losses were 0.9 ± 0.7 mm and 0.9 ± 0.8 mm at 6 months, respectively, and 1 ± 0.65 mm and 1.2 ± 0.9 mm at 12 months, respectively. In the tested group, the bone loss was 0.8 ± 0.8 mm at 6 months and 1.2 ± 0.9 mm at 12 months. In the control group, the bone loss was 1.0 ± 0.7 mm at 6 months and 0.95 ± 0.6 mm at 12 months. There were no statistically significant differences in bone loss between the two groups. Taking both groups together, there were no statistically significant difference in bone loss between patients with or without histories of periodontitis, but there was a statistically significant difference in bone loss between the mandible and maxilla as well as between unitary and total edentations and between partially and total edentulous patients.

Conclusion

At 6 and 12 months, the peri-implant bone loss in sockets preserved with DFDBA and platelet concentrates was similar to the peri-implant bone loss in native bone.

Effect of platelet-rich plasma on patients after blepharoplasty surgery

AIM

To evaluate the effect of platelet-rich plasma (PRP) treatment on patients after blepharoplasty surgery.

MATERIALS AND METHODS

After undergoing blepharoplasty, 20 patients were randomly divided into two groups (n = 10 each). One was treated with autologous PRP and the other was not given any post-surgery treatment (basal group). Autologous PRP application was performed intradermically 24 h, 1 month, and 2 months post-surgery, and the outcome of the applications was assessed 1, 2, and 3 months post-surgery. The postoperative wound was assessed on a patient and observer scar assessment scale (POSAS) by patients and by an unblinded clinical observer. Statistical comparison between the two groups was analyzed by using the Mann-Whitney unpaired, two-tailed test. Significant differences were considered with P ≤ 0.05.

RESULTS

Patient-reported data indicate that compared to the basal group, the PRP group showed no significant differences regarding pain, itching, or color, but had better values for stiffness and thickness (months 1 and 2) as well as scar irregularity (month 1). Data reported by the clinical observer showed that in comparison with the basal group, the PRP group showed no differences in vascularization or pigmentation, but had lower (better) scores regarding thickness, relief, and pliability (at all assessment times). The total assessment values from patients and the observer were significantly better for the PRP than the basal group.

CONCLUSION

Autologous PRP treatment enhanced some parameters associated with healing properties, suggesting a potential therapeutic value after blepharoplasty surgery.

Effects of Growth Factors From Platelet-Rich Fibrin on the Bone Regeneration

Platelet-rich fibrin (PRF) has simple manufacturing process without risk of immunologic rejection or infection by additional materials. This study was designed to investigate the effects of platelet-derived growth factors and transforming growth factors-β in PRF on the proliferation and differentiation of osteoblasts. The authors analyzed platelet-derived growth factors and transforming growth factors-β in normal human serum (NHS) and PRF by enzyme-linked immunosorbent assay quantitatively and those in PRF group were significantly increased when compared with NHS. After harvesting osteoblasts from iliac bone, the authors added 10% fetal bovine serum, 10% NHS, and 3% PRF to osteoblasts, respectively and incubated for 24, 48, 72 hours. For analysis of osteoblast proliferation and differentiation, the authors measured DNA synthesis by [3H]-thymidine isotope activity, protein synthesis by sulforhoamine B assay and those were increased according to elapsed time in all groups, but they were significantly increased in 3% PRF. The authors measured alkaline phosphatase activity of osteoblasts, it was increased according to elapsed to time in all groups, but significantly increased in 72 hours. In conclusion, application of PRF to bone defect sites may have an enhanced effect of bone regeneration with low risk of complications, and relatively simple manufacturing process.

A Comparative Study of Combined Dermaroller and Platelet-Rich Plasma Versus Dermaroller Alone in Acne Scars and Assessment of Quality of Life Before and After Treatment

Background:

Scarring due to acne is a frequently encountered problem in dermatological outpatient department. Microneedling has been a well-accepted modality for the treatment of atrophic acne scars. Platelet-rich plasma (PRP) is a newer option to investigate.

Aims:

The aims of this study were (1) to compare the efficacy of combined dermaroller and PRP therapy with dermaroller alone in facial acne scars and (2) to assess the psychosocial impact due to acne scars and its treatment.

Methods:

A total of 55 patients were included in the study and randomly divided into two groups, Group A: 28 and Group B: 27. Proper counseling was done, and detailed clinical findings were recorded. Patients in Group A were treated with dermaroller alone while Group B patients underwent treatment with a combination of dermaroller and intradermal PRP injections. A total of three sitting were done at monthly interval. Final response was assessed at 1 month after the last sitting. Criteria of evaluation included Goodman and Baron's quantitative scale, visual analog score, and dermatology life quality index scores. Side effects were noted. Results were analyzed using Chi-square test and t-test.

Results:

Significant percentage improvement was noted in both the groups. However, Group B treated with both modalities had better results when compared with that in the Group A.

Conclusion:

A combination approach using dermaroller and PRP was a safe and better option than using dermaroller alone in atrophic acne scars for clinical improvement as well as for improvement in dermatology life quality index score.

Platelet-rich plasma with keratinocytes and fibroblasts enhance healing of full-thickness wounds

Advances in tissue engineering led to the development of various tissue-engineered skin substitutes (TESS) for the treatment of skin injuries. The majority of the autologous TESS required lengthy and costly cell expansion process to fabricate. In this study, we determine the possibility of using a low density of human skin cells suspended in platelet-rich plasma (PRP)-enriched medium to promote the healing of full-thickness skin wounds. To achieve this, full-thickness wounds of size 1.767 cm² were created at the dorsum part of nude mice and treated with keratinocytes (2 × 10⁴ cells/cm²) and fibroblasts (3 × 10⁴ cells/cm²) suspended in 10% PRP-enriched medium. Wound examination was conducted weekly and the animals were euthanized after 2 weeks. Gross examination showed that re-epithelialization was fastest in the PRP+cells group at both day 7 and 14, followed by the PRP group and NT group receiving no treatment. Only the PRP+cells group achieved complete wound closure by 2 weeks. Epidermal layer was presence in the central region of the wound of the PRP+cells and PRP groups but absence in the NT group. Comparison between the PRP+cells and PRP groups showed that the PRP+cells-treated wound was more mature as indicated by the presence of thinner epidermis with single cell layer thick basal keratinocytes and less cellular dermis. In summary, the combination of low cell density and diluted PRP creates a synergistic effect which expedites the healing of full-thickness wounds. This combination has the potential to be developed as a rapid wound therapy via the direct application of freshly harvested skin cells in diluted PRP.

Alveolar Ridge Preservation After Tooth Extraction with DFDBA and Platelet Concentrates: A Radiographic Retrospective Study

Objectives:

The purpose of this study was to evaluate vertical alveolar bone loss 3 months after tooth extraction when a technique of ridge preservation was applied using a particulate demineralized freeze-dried bone allograft 300 - 500 µm associated with platelet concentrates (platelet-rich-fibrin) in the form of gel and membranes.

Material and Methods:

A retrospective radiological clinical study was conducted on 56 patients for whom 95 extractions had been performed immediately followed by alveolar filling. Among the patients, 17 were smokers and 16 were provided with an immediate removable temporary prosthesis after extractions. Vertical bone loss was measured radiologically by panoramic X-ray before extractions and by a computed tomography scan 3 months after, at the level of mid-buccal bone wall, by two independent observers. For statistical analysis, Student’s t-test was performed to compare the mean bone loss between mono- and pluri-radicular teeth and to compare the mean bone loss between tobacco users versus non users and finally to compare the mean bone loss between individuals that had provisional removable prosthesis and those that had not.

Results:

Three months after tooth extraction, the mean of vertical loss of the mid-buccal bone wall was 0.72 (SD 0.71) mm (5.53% SD 5.19). No significant difference between bone loss at mono-radicular and pluri-radicular teeth (P = 0.982) was observed. There was no significant correlation between tobacco habits and bone loss (P = 0.2), nor between provisional removable prosthesis and bone loss (P = 0.786).

Conclusion:

These results indicate a good potential for the technique using Demineralized Freeze-Dried Bone Allograft 300 - 500 µm and platelet concentrates in alveolar bone preservation.

Effects of Platelet-Rich Plasma on Kidney Regeneration in Gentamicin-Induced Nephrotoxicity

Platelet-rich plasma (PRP) as a source of growth factors may induce tissue repairing and improve fibrosis. This study aimed to assess the effects of PRP on kidney regeneration and fibrosis in gentamicin (GM)-induced nephrotoxicity rat model by stereological study. Thirty-two male rats were selected. Nephrotoxicity was induced in animals by administration of GM (80 mg/kg/daily, intraperitoneally [IP], 8 day) and animals were treated by PRP (100 μL, intra-cortical injection using surgical microscopy, single dose). Blood samples were collected for determine blood urea nitrogen (BUN) and creatinine (Cr) before and after PRP therapy. At the end of experiment, right kidneys were sectioned by Isotropic Uniform Random (IUR) method and stained with H & E and Masson's Trichrome. The stereological methods were used for estimating the changes in different structures of kidney. PRP increased the number of epithelial cells in convoluted tubules, and decreased the volume of connective tissue, renal corpuscles and glomeruli in GM-treated animals (P < 0.05). Our findings indicate that PRP had beneficial effects on proliferation of epithelial cells in convoluted tubules and ameliorated GM-induced fibrosis.

The Clinical Efficacy of Autologous Platelet-Rich Plasma Combined with Ultra-Pulsed Fractional CO2 Laser Therapy for Facial Rejuvenation

Ultra-pulsed fractional CO₂ laser is an efficient, precise, and safe therapeutic intervention for skin refreshing, although accompanied with prolonged edema and erythema. In recent years, autologous platelet-rich plasma (PRP) has been proven to promote wound and soft tissue healing and collagen regeneration. To investigate whether the combination of PRP and ultra-pulsed fractional CO₂ laser had a synergistic effect on therapy for facial rejuvenation. Totally, 13 facial aging females were treated with ultra-pulsed fractional CO₂ laser. One side of the face was randomly selected as experimental group and injected with PRP, the other side acted as the control group and was injected with physiological saline at the same dose. Comprehensive assessment of clinical efficacy was performed by satisfaction scores, dermatologists' double-blind evaluation and the VISIA skin analysis system. After treatment for 3 months, subjective scores of facial wrinkles, skin texture, and skin elasticity were higher than that in the control group. Similarly, improvement of skin wrinkles, texture, and tightness in the experimental group was better compared with the control group. Additionally, the total duration of erythema, edema, and crusting was decreased, in the experimental group compared with the control group. PRP combined with ultra-pulsed fractional CO₂ laser had a synergistic effect on facial rejuvenation, shortening duration of side effects, and promoting better therapeutic effect.

Clinical and histological findings of cutaneous wound healing in the red-eared slider turtle (Trachemys scripta elegans) housed in unheated outdoor enclosures

BACKGROUND

Cutaneous wounds are common in chelonians. The clinical and histological features of wound healing in these species are not well described and this prevents evaluation of new therapies.

OBJECTIVES

To describe clinical and histopathological features of cutaneous wound healing in the red-eared slider turtle (Trachemys scripta elegans).

ANIMALS

Twenty four healthy adult females housed in outdoor facilities with free access to water and exposed to daily variations in temperature.

METHODS

Full thickness 6 mm skin biopsy punch wounds were created in the rear limbs. The turtles were assigned to Group 1 (n = 12 for clinical evaluation) and Group 2 (n = 12 for microscopic study). Group 1 was photographed on Day 1 and weekly, until 28 days post wounding. Wound retraction was expressed as the percentage of perimeter reduction. For Group 2, three skin wounds were sampled at 2, 7, 14, 21, 28, 42, 60 and 135 days post wounding for histological study. The avidin-biotin-peroxidase (ABC) staining method was used to evaluate five commercial antibodies.

RESULTS

Wound contraction was limited; crust persisted at least 28 days. Re-epithelialization was complete by Day 14 in many animals; active inflammation persisted until 28 days; connective tissue re-constitution and remodelling was achieved from 42 to 135 days. Antibodies AE1/AE3, Factor VIII, MAC 387, CD3 and NCL-MSA showed cross reactivity with the cell counterpart in turtle tissues.

CONCLUSIONS AND CLINICAL IMPORTANCE

Second intention wound healing progressed slowly and with an indolent behaviour. Microscopically there was marked overlapping of the inflammatory and proliferative phases over a long time period.

Autologous platelet-rich plasma: evidence for clinical use

PURPOSE OF REVIEW

Autologous platelet-rich plasma (aPRP) is growing in popularity as a therapy to augment wound healing, speed the recovery from muscle and joint injuries, and enhance recovery after surgical repair. High-profile athletes treated with aPRP have increased the demand from the general population. Yet, evidence to support the use of aPRP in most clinical settings is weak, because of poorly controlled clinical trials.

RECENT FINDINGS

Preparations of aPRP vary by platelet count, leukocyte content, and degree of platelet activation. Nonetheless, these heterogeneous preparations are used in trials to assess the efficacy of aPRP treatment.

SUMMARY

Despite weak evidence, the use of aPRP continues to grow. High-quality randomized controlled trials are needed to validate or repudiate the potential efficacy of aPRP. Standards for aPRP preparation and quality should be created.

Should we use platelet-rich plasma as an adjunct therapy to treat "acute wounds," "burns," and "laser therapies": A review and a proposal of a quality criteria checklist for further studies

Platelet-rich plasma seems to help wound healing. The goal of this review is to determine if the adjunction of platelet-rich plasma enhances the clinical outcome of acute wounds, burns, and laser therapies. A PubMed and Cochrane library search was performed by two reviewers with the senior author as a consultant. Medical Subject Headings search terms used were the following: ["Platelet-rich plasma" OR "Platelet gel" OR "Platelet growth factor"] AND ["Acute wound" OR "Wound" OR "Burn" OR "Laser"]. We included controlled studies assessing the clinical outcome of acute wounds, burns, and laser therapies treated by platelet-rich plasma. Nine randomized controlled studies, six prospective controlled studies, and two retrospective controlled studies were included. Regarding acute wounds, three randomized controlled trials found a statistical benefit regarding either the healing time, the return back to work time, the quality of life, or the pain and three prospective controlled studies found a statistical difference regarding the velocity of healing. Platelet-rich plasma decreased the intensity or duration of erythema after laser therapy in four randomized studies. Regarding the long-term outcome of laser therapies, two studies found a statistical benefit and two others did not. Platelet-rich plasma accelerates acute wound healing and decreases erythema after laser therapies. Its use on burns has not been enough studied.

Use of autologous platelet-rich plasma in complete cleft palate repair

OBJECTIVES/HYPOTHESIS

Evaluate the effect of topical application of autologous platelet-rich plasma (PRP) in primary repair of complete cleft palate and then compare the result with another group of patients using the same surgical technique, without application of PRP with regard to the incidence of oronasal fistula, velopharyngeal closure, and grade of nasality.

STUDY DESIGN

Case control study.

METHODS

This study was carried on 44 children with complete cleft palate with age range from 12 to 23 months. The children were divided into two age- and gender-matched groups: All children were subjected to the same technique of V-Y pushback repair of the complete cleft palate. In group A (22 children), the PRP prepared from the patient was topically applied between the nasal and oral mucosa layer during palatoplasty, whereas in group B (22 children) the PRP was not applied.

RESULTS

All cases were recovered smoothly without problems. In group A, no oronasal fistula was reported, whereas in group B three patients (13.6%) had postoperative fistulae and two patients (9.1%) needed revision palatoplasty. At 6 months postoperative assessment, group A (with PRP application) showed significantly better grade of nasality (P = 0.024) and better endoscopic velopharyngeal closure (P = 0.016) than group B.

CONCLUSION

Usage of autologous PRP in complete cleft palate repair is simple; effective; can decrease the incidence of oronasal fistula; and also significantly improves the grade of nasality and velopharyngeal closure, which decreases the need of further surgical intervention in cleft palate patients.

LEVEL OF EVIDENCE

3b. Laryngoscope, 126:1524-1528, 2016.

Effect of autologous platelet-rich plasma application on cutaneous wound healing in dogs

This study was conducted to identify the effectiveness of platelet-rich plasma (PRP) and efficacy of intralesional injection as a method of application to acute cutaneous wounds in dogs. Healthy adult beagles (n = 3) were used in this study. Autologous PRP was separated from anticoagulant treated whole blood in three dogs. Cutaneous wounds were created and then treated by intralesional injection of PRP in the experimental group, while they were treated with saline in the control group on days 0, 2 and 4. The healing process was evaluated by gross examination throughout the experimental period and histologic examination on day 7, 14 and 21. In PRP treated wounds, the mean diameter was smaller and the wound closure rate was higher than in the control. Histological study revealed that PRP treated wounds showed more granulation formation and angiogenesis on day 7, and faster epithelialization, more granulation formation and collagen deposition were observed on day 14 than in control wounds. On day 21, collagen deposition and epithelialization were enhanced in PRP treated groups. Overall, PRP application showed beneficial effects in wound healing, and intralesional injection was useful for application of PRP and could be a good therapeutic option for wound management in dogs.

Use of platelet-rich plasma in deep second- and third-degree burns

Unfortunately burns are a common occurrence, leading to scarring or death. Platelet-rich plasma (PRP) contains many growth factors that can accelerate wound healing. We analyzed the use of PRP in deep second-degree (dSD), deep second-degree associated with diabetes mellitus (dSDD), and third-degree (TD) burns in rats. Sixty syngeneic rats divided into three groups (dSD, dSDD, and TD) were burned, half receiving topical PRP and half being used as control; 10 additional rats per group were used for PRP preparation. On day 21, the animals were sacrificed and skin biopsies were collected. dSD and dSDD wounds treated with PRP showed faster wound closure, reduction in CD31-, CD68-, CD163-, MPO-, and in TGF-β-positive cells, and an increase in MMP2-positive cells. The neo-epidermis was thinner in the control of both the dSD and dSDD groups and granulation tissue was less reduced in the control of both the dSDD and TD groups. These results indicate that PRP can accelerate the healing process in dSD and dSDD, but not in TD burns.

The influence of growth factors on skin wound healing in rats

Introduction

Healing is a process that restores the physical integrity of body structures. It is a dynamic, complex, multicellular process that involves the extracellular matrix, cytokines, blood cells, and growth factors. Growth factors are proteins that activate and stimulate cell proliferation through the activation of angiogenesis, mitogenesis, and gene transcription, accelerating the healing process.

Objective

To assess the influence of growth factors on the healing process of wounds made on the backs of female rats compared to the control wound, through macro and microscopy.

Methods

This study used 45 female Wistar rats, in which three wounds were made on the back. The first was the control wound, the second received epithelial growth factor injection, and the third received a combination of factors. Macroscopic and microscopic assessments were performed on the third, seventh, and 15th days of the experiment. For microscopic analysis, hematoxylin–eosin staining was utilized to assess the inflammatory process; vimentin, for assessment of blood vessels and fibroblasts, and Sirius Red for collagen assessment.

Results

In the macroscopic assessment, the use of growth factors resulted in faster healing and decrease of granulation tissue on days seven and 15; (80.31% reduction in the control wound vs. 83.24% in the epithelial wound vs. 100% in the mixed wound). Utilizing microscopy, at the three stages of the experiment, there were no significant differences between the three wounds; however, when comparing the day of euthanization for each type of wound, there was a favorable outcome for epithelial and mixed wounds (between the third vs. 15th day, p < 0.001, and in the comparison of the seventh vs. 15th day; p = 0.002 and p = 0.001 for epithelial and mixed wounds, respectively) with a higher number of fibroblasts, angiogenesis, and collagen type I.

Conclusion

The use of growth factors accelerates healing, stimulates greater angiogenic activity, and accelerates fibroplasia and collagen maturation.

Platelet Preparations for Use in Facial Rejuvenation and Wound Healing: A Critical Review of Current Literature

In facial plastic surgery, the potential for direct delivery of growth factors from platelet preparations has been of particular interest for use in facial rejuvenation, recovery after facial surgery, and wound healing. A literature search was conducted through PubMed for the terms PRP, PRFM, platelet-rich plasma, platelet-rich fibrin matrix, platelet preparations, platelet therapy, growth factors, platelet facial, platelet facial rejuvenation, platelet wound healing, platelet plastic surgery. Articles pertaining to the use of platelet preparations in facial surgery and wound healing in plastic surgery after 2001 were included. Thirteen in vitro studies showed use of platelet-rich plasma (PRP) and platelet-rich fibrin matrix (PRFM) had a significant effect on cellular activity. Twenty-four out of 28 animal studies exhibited favorable results with use of a platelet preparation, including five of six studies that showed enhanced fat graft survival with addition of a platelet preparation. Twenty-three case series and clinical trials were identified, only two of which showed no differences. Twenty-one reported favorable results with use of various platelet preparations. A total of 47 studies used PRP, four studies evaluated Leukocyte-rich PRP, and fourteen studies used PRFM. The vast majority of studies examined show a significant and measurable effect on cellular changes, wound healing, and facial esthetic outcomes with use of platelet preparations, both topical and injectable. One must also consider possible publication bias against null results that may have had an influence on the data that were available for review. However, the preponderance of studies suggests that platelet preparations might represent an as-of-yet untapped adjunct in facial plastic surgery.

Effect of platelet-rich plasma on the healing of cutaneous defects exposed to acute to chronic wounds: a clinico-histopathologic study in rabbits

Background

Platelet-rich plasma (PRP) contains numerous growth factors to promote wound healing and angiogenesis. The aim of this study was to gain further information about the benefits of platelet-rich-plasma for healing cutaneous acute to chronic wounds.

Methods

A total of 30 New Zealand albino rabbits (n = 15/group) were randomly assigned to two experimental groups: control group, and PRP group. Bilateral resection defects measuring 3 cm were surgically created on the dorsolateral of the cutaneous in animals and the defects were randomly divided into two mentioned groups. Wound area, neovascularization, size and epithelialization were compared on days 7, 14 and 21 post-wounding. Histopathological analyses were conducted on 15 specimens from each group after sacrifice by the cellular aspects of the regeneration of the tissue.

Results

Our results were indicated that the wound area of PRP was smaller than that in the non-treated group on days 7, 14 and 21. Furthermore, a significant decrease of the wound size was observed in PRP groups that were significantly greater than that in the control group. A significant increase of the mean vascular density was noted in the PRP treated groups compared to the control groups at day 14 and especially day 21. This results indicated that PRP treated group’ enhanced angiogenesis at the wound beds as compared to no treatment group.

Conclusion

These results could be useful for researchers in the growing fields of tissue repair and experimental wound healing. Further studies will be essential to determine the role of PRP in clinical practice.

Effect of locally injected autologous platelet-rich plasma on second intention wound healing of acute full-thickness skin defects in dogs

OBJECTIVES

Second intention wound healing may be impaired by wound and host factors and thus more advanced therapies are required for a fast and satisfactory outcome. Platelet-rich plasma (PRP), rich in growth factors and cytokines essential for tissue repair, could improve wound healing. The purpose of this experimental study was to evaluate the effect of locally injected autologous PRP on second intention healing of acute full-thickness skin defects in dogs.

METHODS

Three 2 x 2 cm full-thickness skin defects were created bilaterally on the dorsolateral area of the trunk of six Beagle dogs. The wounds of one randomly selected side received PRP treatment, whereas the contralateral wounds were left untreated (controls). Wound healing was evaluated by planimetry, laser-Doppler flowmetry measurements of tissue perfusion, and histologically.

RESULTS

The rate of wound healing did not differ significantly between the two groups. Tissue perfusion was significantly higher in the PRP-treated group (p = 0.008) compared to controls on day 10. Histological evaluation revealed a trend towards greater collagen production and a significantly better collagen orientation (p = 0.019) in PRP-treated wounds on day 20.

CLINICAL SIGNIFICANCE

Locally injected autologous PRP does not accelerate the healing process, but increases tissue perfusion and may promote the formation of organized collagen bundles in acute full-thickness skin defects in dogs.

Considerations on the use of platelet-rich plasma, specifically for burn treatment

Platelet-rich plasma (PRP) is a fraction of blood plasma with a platelet concentration above baseline. After activation of the platelets, growth factors are released, which are involved in wound-healing processes. Application of a multitude of growth factors seems to boost the healing process. In this review the authors provide a comprehensive overview of the many different aspects of PRP; this is followed by a short outline of the evidence for a wide range of applications and finally narrowing down to a more in-depth analysis of the literature on the potential use of PRP in burn treatment. The authors performed an extensive search on PRP and the different biological, as well as practical aspects for the different applications. Furthermore, we performed a systematic search on PRP in the treatment of burn wounds. A high variety exists in PRP products, procedures, and content. This makes interpretation and comparison of the evidence difficult. PRP has been reported to have beneficial effects on wound healing in different fields of surgery and in the treatment of acute, chronic, and diabetic wounds. Literature on the use of PRP in burns is scarce. Separate growth factors have shown beneficial results in the treatment of burns. Furthermore, an animal study and several case reports showed improved burn wound-healing time after the application of PRP. A deep dermal burn could benefit from PRP through its hemostatic antimicrobial abilities and the positive effects seen in wound healing. However, burn patients have an altered physiological state and it is unknown how this may affect platelet function and quality. Furthermore, the effect of PRP on scarring has not been evaluated properly. Future research is needed to elucidate the role of PRP in the treatment of burns.

Fibrin network architectures in pure platelet-rich plasma as characterized by fiber radius and correlated with clotting time

Fibrin networks are obtained through activation of platelet-rich plasma (PRP) for use in tissue regeneration. The importance of fibrin networks relies on mediation of release of growth factors, proliferation of tissue cells and rheological properties of the fibrin gels. Activation of PRP usually involves the decomposition of fibrinogen by agonists, in a wide range of concentrations. Therefore fibrin networks with a large structural diversity are formed, making comparative evaluations difficult. In order to standardize the fibrin networks, we used the statistical techniques central composite rotatable design and response-surface analysis, to correlate the radius of the fibers with the ratios between the agonists (autologous serum/calcium chloride) and agonist/PRP. From an individual and interactive analysis of the variables, architectures characterized by thick, medium and thin fibers were delineated on the response-surface. Furthermore, the architectures were correlated with coagulation time. This approach is valuable for standardizing the PRP preparation for clinical applications.