The use of platelet-rich plasma in oral surgery: a systematic review and meta-analysis

Platelet rich plasma for facial rejuvenation: an overview of systematic reviews

BACKGROUND

Platelet-rich plasma (PRP) as a non-surgical therapy for facial rejuvenation is increasingly adopted. This article aims to review the literature and critically appraise the available evidence regarding the efficacy and safety of PRP for facial rejuvenation.

MATERIAL AND METHODS

An overview of systematic reviews (SRs) of PRP use for facial rejuvenation. The methodological quality of the SRs was assessed using the AMSTAR-2 checklist; quality of the evidence from the trials included in each SR was appraised following the GRADE approach.

RESULTS

Thirteen SRs published between 2015 and 2023, reporting data from 114 overlapping reports, based on 28 individual primary studies (18 uncontrolled reports), were included in this umbrella review. Eight primary studies evaluated PRP in combination with other treatments (laser therapy, fat grafting, hyaluronic acid, basic fibroblast growth factor), and 20 PRP monotherapy. Most of the included primary studies were uncontrolled, and meta-analysis for outcomes related to facial rejuvenation was conducted in only 1 of the 13 SRs, showing that patients treated with PRP as an adjunct treatment have increased satisfaction over controls without PRP (mean difference, 0.63; 95% confidence intervals (CIs) 0.25/1; p=0-001; low certainty of evidence due to risk of bias (ROB) and inconsistency). No other quantitative data were available from the SRs, although 4 SRs concluded in a descriptive way reveal that PRP combined with laser therapy increased subject satisfaction and skin elasticity, and decreased the erythema index (very low certainty of evidence due to imprecision, unsystematic clinical observations, and ROB). The occurrence of adverse events was a predefined outcome in only 2 SRs (15%). Almost all the SRs demonstrated poor compliance with the AMSTAR 2 items, and the confidence in the results of SRs was graded as low or critically low in 12 of the 13 SRs.

DISCUSSION

The available evidence is insufficient to suggest firm conclusions about the use of PRP, alone or in combination with other treatments, in promoting facial rejuvenation.

Current Challenges in the Development of Platelet-Rich Plasma-Based Therapies

Nowadays, biological therapies are booming and more of these formulations are coming to the market. Platelet-rich plasma, or PRP, is one of the most widely used biological therapies due to its ease of obtention and autologous character. Most of the techniques to obtain PRP are focusing on new processes and methods of optimization. However, not enough consideration is being given to modify the molecular components of PRP to generate more effective formulations with the aim of improving PRP treatments. Therefore, this review covers different novel PRP-obtaining methods that attempt to modify the molecular composition of the plasma.

Platelet rich plasma use for treatment of acne scars: an overview of systematic reviews

BACKGROUND

A reappraisal of the conclusions of systematic reviews (SRs) and meta-analyses validity related to Platelet-rich plasma (PRP), alone or in combination with other treatments, compared to regimens PRP-free for the treatment of acne scars.

MATERIALS AND METHODS

An overview of SRs. The methodological quality of the reviews was assessed using AMSTAR-2 checklist; quality of the evidence of primary studies was appraised following the GRADE approach.

RESULTS

Fifteen SRs were included in this overview. Data were from 124 overlapping reports, based on 34 individual primary studies (10 parallel arm randomized trials, 21 split-face studies, and 3 uncontrolled studies). Most of the studies evaluated combination of PRP with microneedling or with laser therapy compared to microneedling or laser therapy without PRP. Clinical improvement (reported as degree of improvement or improvement score) and patient's satisfaction rate were significantly higher in PRP recipients compared to controls. Crusting time and duration of erythema were significantly shorter in PRP recipients compared to controls. Most of the reviews considered in this overview can be considered of low methodological quality due to the fact that several critical methodological requirements of AMSTAR-2 checklist were unmet or partially met; only 6 of the 15 reviews incorporated study quality in their conclusions, and no GRADE assessment was performed for the reported outcomes in any of the SRs. With the GRADE approach, the quality of the evidence for the outcomes analysed ranged from very low to low due to risk of bias in the primary studies, inconsistency between the studies, and imprecision.

DISCUSSION

The low or very low certainty of evidence does not support clear clinical decision about the PRP use in combination with microneedling or laser therapy for the treatment of acne scars. Further well-designed studies are required to improve the evidence base for PRP combination therapy for acne scars.

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

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

Biotherapeutic Applications of Platelet-Rich Plasma in Regenerative Medicine

BACKGROUND

Platelet-rich plasma (PRP), a blood-based product containing platelets and growth factors, is being utilized to treat numerous non-hemostatic disorders. Studies have explored the use of PRP to provide rapid repair, healing, and recovery from various injuries; some studies mentioned the effectiveness of PRP as compared with other forms of treatment like the use of hyaluronic acid. Commercially available PRP systems are available now, and each varies from one another depending on how it is prepared, thus causing variations in platelet concentration and growth factor content. These variations also implicated different therapeutic applications.

METHODS

The paper reviews the various applications of PRP, including factors to consider before using PRP therapy, and provides an extensive list of PRP applications.

RESULTS

The administration of PRP as a standalone treatment or as a co-therapy results in observed positive outcomes. However, there is a lack of standardization for PRP preparation, increasing the risks for heterogeneity and bias amongst results.

CONCLUSION

The use of PRP is indeed an option for regenerative therapy, but more research is needed before it can fully be recommended as a primary treatment modality.

Advanced platelet-rich-fibrin (A-PRF +) has no additional effect on the healing of post-extraction sockets of upper third molars. A split mouth randomized clinical trial

PURPOSE

This study evaluated  the effects of advanced platelet-rich fibrin (A-PRF +) on the healing of upper third molar post-extraction sockets.

METHODS

Sixteen patients who underwent extractions of the upper third molars (18 and 28) were included in this randomized split-mouth study. The alveoli on the test side were filled with A-PRF + , while the control side was maintained with blood clot. The side that received treatment was randomly defined. Alveolar bone regeneration was evaluated by CBCT scans to assess healing stage, bone density, and fractal analysis 1 week and 90 days post-extraction. Additionally, pain, edema, bleeding, and soft tissue alveolar repair were evaluated by clinical analyses 3, 7, 14, 30, and 90 days after the surgical procedure using a visual analog scale.

RESULTS

There were no clinical differences regarding treatments in any experimental period. In the tomographic evaluation, at 7 days, the alveoli treated with A-PRF + presented a suggestive sign of higher bone density than the control alveoli, which was not confirmed 90 days after the surgical procedure.

CONCLUSION

Thus, the use of A-PRF + does not demonstrate a clinical advantage in the repair of post-extraction sockets of upper third molars.

Platelet-rich plasma for the treatment of alopecia: a systematic review and meta-analysis

BACKGROUND

The number of articles evaluating the efficacy of platelet-rich plasma (PRP) in androgenetic alopecia (AGA) and alopecia areata (AA) has increased exponentially during the last years. This systematic review and meta-analysis is aimed at evaluating the benefit of PRP in the treatment of alopecia.

MATERIAL AND METHODS

We searched MEDLINE (through PUBMED), Embase, and CENTRAL for relevant data. Treatment effect was described by mean difference (MD) and risk difference with 95% confidence intervals (CI). The GRADE system was used to assess the certainty of the body of evidence.

RESULTS

We found 27 controlled trials (1,117 subjects) that met our inclusion criteria: 18 trials (713 subjects) in patients with AGA, and 9 (404 subjects) in patients with AA. Eleven studies had a split head design. There was heterogeneity in types of PRP (e.g., activated and non-activated) and administration schedules. PRP was compared to saline injections (18 studies), local steroid injections (4 studies) and other comparators (5 studies). Most commonly reported outcomes were hair density and hair regrowth. It was not possible to pool all outcome data because of heterogeneity in reporting, and because reporting was often limited to a single study. Compared to saline injections, PRP injections increased hair density over a medium-term follow-up (MD, 25.6 hairs/cm²; 95 % CI: 2.62-48.57), but the evidence was rated as low quality due to inconsistency and risk of bias. In individuals with AA, it is unclear whether PRP injection compared with triamcinolone injection increase the rate of subjects with hair regrowth (very-low quality of evidence due to inconsistency, imprecision, and risk of bias). There were no serious adverse events related to PRP injection or control treatments.

CONCLUSIONS

There is limited evidence showing benefit of PRP for treatment of alopecia, and most of this evidence is of low quality.

Cell-based therapy in thin endometrium and Asherman syndrome

Numerous treatment strategies have so far been proposed for treating refractory thin endometrium either without or with the Asherman syndrome. Inconsistency in the improvement of endometrial thickness is a common limitation of such therapies including tamoxifen citrate as an ovulation induction agent, acupuncture, long-term pentoxifylline and tocopherol or tocopherol only, low-dose human chorionic gonadotropin during endometrial preparation, aspirin, luteal gonadotropin-releasing hormone agonist supplementation, and extended estrogen therapy. Recently, cell therapy has been proposed as an ideal alternative for endometrium regeneration, including the employment of stem cells, platelet-rich plasma, and growth factors as therapeutic agents. The mechanisms of action of cell therapy include the cytokine induction, growth factor production, natural killer cell activity reduction, Th17 and Th1 decrease, and Treg cell and Th2 increase. Since cell therapy is personalized, dynamic, interactive, and specific and could be an effective strategy. Despite its promising nature, further research is required for improving the procedure and the safety of this strategy. These methods and their results are discussed in this article.

The effectiveness of locally injected platelet-rich plasma on orthodontic tooth movement acceleration

OBJECTIVES

To critically appraise the current evidence available from animal studies pertaining to the effectiveness of platelet-rich plasma (PRP) in accelerating orthodontic tooth movement.

MATERIALS AND METHODS

Electronic searches of nine databases were conducted up to June 2020, followed by a hand search of the reference list of eligible studies. The study design required was prospective controlled animal studies. The primary outcome assessed was the rate of orthodontic tooth movement. The secondary outcome evaluated was histological changes after PRP application. Following study retrieval and selection, relevant data were extracted. Risk-of-bias (RoB) assessment was done using the Systematic Review Center for Laboratory Animal Experimentation's Risk of Bias Tool (SYRCLE's Risk of Bias Tool). Two review authors conducted the work of searching, study selection, and quality assessment independently and in duplicate.

RESULTS

Of 193 studies, 5 animal studies were included in this systematic review. Three studies found a positive correlation between PRP injection and tooth movement acceleration, along with corresponding histological changes. Two studies detected no significant difference in tooth movement rate after PRP application.

CONCLUSIONS

Based on the current limited evidence, the efficacy of PRP on tooth movement acceleration remains debatable. More well-designed randomized controlled trials involving humans are called for to obtain more clinically significant conclusions.

A Systematic Critical Appraisal of the Methodological Quality of Systematic Reviews on the Effect of Autologous Platelet Concentrates in the Treatment of Periodontal Intraosseous Defects

The present study aimed to perform a systematic critical appraisal of the methodological quality of systematic reviews (SRs) on the effect of autologous platelet concentrates (APCs) in the treatment of periodontal intraosseous defects and to provide a synthesis of the main clinical findings available. An electronic and hand search was performed up to February 2020; 14 systematic reviews of randomized controlled trials (RCTs), of which 11 were meta-analyses, were included. Only one SR fully satisfied all 11 items of the AMSTAR (“A Measurement Tool to Assess Systematic Reviews”) checklist for methodological quality evaluation, 3 SRs were classified of high quality, 8 of medium quality, and 2 of low quality. There is some evidence on the beneficial additive effect of APCs in the surgical treatment of intraosseous defects when used alone or in combination with bone grafts. APCs did not show any advantage when used together with guided tissue regeneration (GTR) or enamel matrix derivative (EMD). Undertaking SRs which adhere to rigorous standards and protocols is strongly recommended. There are increasing data on the positive adjunctive effect of APCs in the surgical treatment of intraosseous defects but, due to the heterogeneity of the available primary studies, the quality of evidence remains rather low and further long-term well-designed RCTs are encouraged.

Modifying MSC Phenotype to Facilitate Bone Healing: Biological Approaches

Healing of fractures and bone defects normally follows an orderly series of events including formation of a hematoma and an initial stage of inflammation, development of soft callus, formation of hard callus, and finally the stage of bone remodeling. In cases of severe musculoskeletal injury due to trauma, infection, irradiation and other adverse stimuli, deficient healing may lead to delayed or non-union; this results in a residual bone defect with instability, pain and loss of function. Modern methods of mechanical stabilization and autologous bone grafting are often successful in achieving fracture union and healing of bone defects; however, in some cases, this treatment is unsuccessful because of inadequate biological factors. Specifically, the systemic and local microenvironment may not be conducive to bone healing because of a loss of the progenitor cell population for bone and vascular lineage cells. Autologous bone grafting can provide the necessary scaffold, progenitor and differentiated lineage cells, and biological cues for bone reconstruction, however, autologous bone graft may be limited in quantity or quality. These unfavorable circumstances are magnified in systemic conditions with chronic inflammation, including obesity, diabetes, chronic renal disease, aging and others. Recently, strategies have been devised to both mitigate the necessity for, and complications from, open procedures for harvesting of autologous bone by using minimally invasive aspiration techniques and concentration of iliac crest bone cells, followed by local injection into the defect site. More elaborate strategies (not yet approved by the U.S. Food and Drug Administration-FDA) include isolation and expansion of subpopulations of the harvested cells, preconditioning of these cells or inserting specific genes to modulate or facilitate bone healing. We review the literature pertinent to the subject of modifying autologous harvested cells including MSCs to facilitate bone healing. Although many of these techniques and technologies are still in the preclinical stage and not yet approved for use in humans by the FDA, novel approaches to accelerate bone healing by modifying cells has great potential to mitigate the physical, economic and social burden of non-healing fractures and bone defects.

Platelet-rich plasma for sports-related muscle, tendon and ligament injuries: an umbrella review

BACKGROUND

Platelet-rich plasma (PRP) has been used in different non-transfusion indications due to its role in tissue regeneration and healing. The aim of this overview of systematic reviews (umbrella review) is to provide a summary of the existing research syntheses related to PRP use for sports-related muscle, tendon and ligament injuries.

MATERIALS AND METHODS

Literature searches were performed in MEDLINE, Embase, and Cochrane Library to identify systematic reviews focusing on PRP use for sports-related muscle, tendon and ligament injuries. The methodological quality of included studies was assessed using the checklist for systematic reviews and research syntheses developed by the Joanna Briggs Institute and the GRADE assessment.

RESULTS

Twenty-two studies met the inclusion criteria. Five studies evaluated PRP use for acute muscle injury, and 17 evaluated PRP use for tendon and ligament injury. Studies were heterogeneous in terms of the dose and number of PRP injections, and the control groups. Three of the 5 reviews evaluating acute muscle injury concluded that PRP had no effect on the outcomes considered. One review shows superior efficacy of rehabilitation exercise compared to PRP. One review shows that PRP may result in an earlier return to sport for acute grade I-II injury. Eight out of the 17 reviews evaluating PRP for tendon and ligament injuries show a statistically significant (p<0.05) difference in pain and/or function outcome measures favouring PRP compared to controls, although most of the observed differences were small. Adverse events data and quality of life outcomes were rarely analysed or reported in the included studies and were considered clinically insignificant.

DISCUSSION

In most of the included reviews, the available evidence was judged to be of low/very low quality due to risk of bias, inconsistency and imprecision, thus making the level of certainty of these findings low and not adequate to support the general use of PRP in this setting.