Role of Platelet Concentrates in Dental-Pulp Regeneration: A Systematic Review of Randomized Clinical Trials.

Statement of the Problem: Treatment of immature necrotic teeth is a problematic situation. Conventional root canal therapy is challenging and leaves a weak, fragile, and undeveloped tooth for lifetime. Purpose: This review was aimed to assess the outcome of available randomized clinical trials (RCTs) on the efficacy of platelet concentrates (PC) in dentine-pulp complex regeneration. Materials and Method: In this systematic review, an electronic search was conducted on MEDLINE, EMBASE, Cochrane, and Google scholar databases. A further manual search was performed on the list of related articles in order to ensure inclusion of potentially missed articles in earlier electronic search. Those proved RCTs matched with the standard criteria were included following an initial assessment of abstracts and the text independently by the reviewers. Results: From the total 602 harvested articles, only 13 met the criteria and were evaluated with 11 having parallel design and 2 split mouth. Only one study featured low risk of bias, while three had moderate risk and the rest were at high risk of bias. Six studies had used platelet rich plasma (PRP), 4 employed platelet rich fibrin (PRF), one utilized injectable platelet rich fibrin (I-PRF), and three used both PRF and PRP for their experimental groups while blood clot (BC) was used as the control group for all. The success rate was reported at 87.3% judged by the absence of pathologic signs and symptoms. Conclusion: Dentin wall thickening, root lengthening and apex closure were higher in PC groups, however, these differences were not statistically significant in reported studies. It can be concluded that PCs promote the pulp tissue revitalization and continuation of root development. However, a consensus on its potency for true pulp regeneration is yet to be reached.

The effect of agitating buffy coats on platelet quality before soft spin.

BACKGROUND: Platelet plays a vital role in both physiological and pathological processes. However, the limited storage time of platelet in vitro poses an immense challenge for its applications because of the increased risk of bacterial contamination and platelet storage lesions. Agitation can inhibit lesions by facilitating continuous oxygenation of platelets and permitting excess carbon dioxide to be removed during storage. However, it is still not known whether agitating BCs gives a positive effect on platelet quality. OBJECTIVES: To evaluate the quality difference between platelet concentrates (PCs) from buffy coats (BCs) held rest and agitation. METHODS: Samples were withdrawn for cell count, blood gas analysis, free hemoglobin level, hypotonic shock response, maximum aggregation rate, activation marker expression (CD62P and CD42b) and coagulation function. RESULTS: We found the PCs prepared from the agitating BCs had fewer residual WBCs, exhibited a better gas exchange ability, slower metabolism (higher pH, higher content glucose, and lower lactic acid levels), better hypotonic shock response, and lower levels of CD62P. The TEG-PC assays showed no difference in coagulation function. CONCLUSION: Our findings showed that BC can be agitated overnight before a soft spin.

Platelet Power: Revitalizing Endodontics With Scaffolds.

This article provides an overview of a biologically based method for restoring damaged tooth structures and pulp tissues known as regenerative endodontics. It explores the concept of regenerative endodontics, its tissue engineering approach, and its application in maintaining vitality. The article discusses the significance of the factors affecting growth, scaffolds, and stem cells being the three tissue engineering components involved in the regeneration of pulp tissues. It also delves into the classification of scaffolds and the role of platelet-rich fibrin (PRF) and platelet-rich plasma (PRP) as biological scaffolds. The methodology section details the search process for relevant studies, and the review section presents research findings associated with PRF and its application in regeneration and repair of tissue. The article concludes by highlighting the potential of advanced PRF and injectable PRF in regenerative endodontics, with a focus on their impact on tissue regeneration and healing.

Evaluation of platelet concentrates prepared using different methods after overnight holding (18-24 h) of whole blood at room temperature.

BACKGROUND AND OBJECTIVES: Regulatory requirement of fixed holding time (6 h) of whole blood (WB) at room temperature, that is, 22-24°C (RT) results in sub-optimal component separation. The aim was to evaluate the platelet concentrates (PC) prepared by both platelet rich plasma (PRP) and buffy coat (BC) methods after overnight hold (18-24 h) at RT. MATERIALS AND METHODS: A prospective experimental study was performed. A total of 48 WB units collected were divided into four groups (12 each) control-1 (C1) and test-1 (T1) for PRP and control-2 (C2) and test-2 (T2) for the BC method. Control groups were processed within 6 h, and in test groups, components were prepared after overnight hold, followed by evaluation of quality parameters. RESULTS: Irrespective of the method used, all PCs had similar volume, platelet yield, swirling, no bacterial contamination, RBC contamination, PaO2 and PaCO2 levels. PCs in the T1 group had significant differences in glucose and MPV values on d1, which were resolved by d5 of storage. PCs in T2 has significant differences in pH, glucose, and MPV levels throughout storage. PRBC in test and control groups had similar quality parameters till d42 of storage. FFPs in all tests were noninferior to the concurrent control groups till 3 months of storage. CONCLUSION: Overnight holding of WB had no lasting deleterious changes. Though a few biochemical parameters in the test groups were significantly different, they can be accepted to improve the logistics of component separation. Overall PRP method seemed to have a better result than the BC method after an overnight hold.

Microneedling with PRP for Acne Scars: A New Tool in Dermatologist Arsenal - A Scoping Review.

Acne scars can greatly impact patient quality of life. While treatment options have included mi- croneedling, the recent addition of platelet-rich plasma (PRP) to this regimen has led to an increased popularity of combination treatment. Here, we aimed to review the efficacy of microneedling and PRP therapies and review the literature on combination treatment for acne scars.

Instructions for the use of L-PRF in different clinical indications.

Autologous platelet concentrates (APCs) have demonstrated clear benefits across various clinical applications, including alveolar ridge preservation, guided tissue regeneration, guided bone regeneration, sinus floor elevation (both lateral window approach and transcrestal technique), endodontic surgery, the treatment of medication-related osteonecrosis of the jaw bones, and periodontal plastic surgery. To ensure an optimal clinical outcome, clinicians must adhere strictly to the protocol to prepare the APCs and, especially follow evidence-based surgical guidelines, often simple but crucial, to minimize the likelihood of errors. The majority of clinical trials reported on second-generation APCs [the leukocyte- and platelet-rich fibrin (L-PRF) family, including its modifications (A-PRF, A-PRF+, CGF, T-PRF, H-PRF, etc.)]. These second-generation APCs offer additional benefits compared to the first-generation APCs, making them the preferred choice for the development of clinical recommendations. These recommendations have been formulated through a meticulous examination of the available clinical data and the clinical experience of the authors of this paper.

The effect of near-infrared low-level light on the in vitro quality of platelets during storage.

BACKGROUND AND OBJECTIVES: Near-infrared (NIR) light has been successfully applied to improve the quality of mouse platelets during storage. Because it is suspected that the mitochondria contain the primary photon acceptor, we hypothesized that human platelets for transfusion may be affected similarly and could benefit from NIR light treatment. MATERIALS AND METHODS: The optimal light dose was determined using portions of platelet concentrates (PCs) in PAS-E. A pool-and-split design was used to prepare PCs in PAS-E or plasma (n = 6). On day 1, one unit of both pairs was illuminated with 830 nm light (light-emitting diodes, 15 J/cm2). PCs were stored at 22°C and sampled regularly for analysis. Data were compared with their corresponding controls with a paired two-sided t-test. RESULTS: Illuminated platelets in PAS-E were less activated with significantly lower CD62P expression (day 8: 10.8 ± 1.8 vs. 12.2 ± 2.6, p < 0.05) and lower Annexin A5 binding (day 8: 11.8 ± 1.9 vs. 13.1 ± 2.4, ns). They produced significantly less lactate resulting in a higher pH (days 6-10). ATP content and mitochondrial membrane potential were not affected. Although these trends were also observed for PCs in plasma, the differences did not reach statistical significance as compared with the control group. CONCLUSION: Our study demonstrates that the glycolysis rate of human platelets can be modulated through the use of NIR, possibly through mitochondrial aerobic metabolism, but this requires confirmation. If NIR illumination can be further optimized, it may potentially become a useful tool in situations in which glycolysis and platelet activation are exacerbated.

Essential principles for blood centrifugation.

Currently, autologous platelet concentrates (APCs) are frequently used for soft- and hard-tissue regeneration, not only within the oral cavity, but also extra-orally including chronic wounds, burns, joints, dermatological conditions, among others. The benefits of APCs are largely influenced by the treatment strategy but also their preparation. This paper therefore discusses in detail: the physical properties of blood cells, the basic principles of blood centrifugation, the impact of the centrifugation protocol (rotations/revolutions per minute, g-force, variation between centrifuges), the importance of timing during the preparation of APCs, the impact of the inner surface of the blood tubes, the use/nonuse of anticoagulants within APC tubes, the impact of the patient's hematocrit, age, and gender, as well as the important requirements for an optimal centrifugation protocol. All these variables indeed have a significant impact on the clinical outcome of APCs.

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

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

Comparative virulome analysis of four Staphylococcus epidermidis strains from human skin and platelet concentrates using whole genome sequencing.

Staphylococcus epidermidis is one of the predominant bacterial contaminants in platelet concentrates (PCs), a blood component used to treat bleeding disorders. PCs are a unique niche that triggers biofilm formation, the main pathomechanism of S. epidermidis infections. We performed whole genome sequencing of four S. epidermidis strains isolated from skin of healthy human volunteers (AZ22 and AZ39) and contaminated PCs (ST10002 and ST11003) to unravel phylogenetic relationships and decipher virulence mechanisms compared to 24 complete S. epidermidis genomes in GenBank. AZ39 and ST11003 formed a separate unique lineage with strains 14.1 .R1 and SE95, while AZ22 formed a cluster with 1457 and ST10002 closely grouped with FDAAGOS_161. The four isolates were assigned to sequence types ST1175, ST1174, ST73 and ST16, respectively. All four genomes exhibited biofilm-associated genes ebh, ebp, sdrG, sdrH and atl. Additionally, AZ22 had sdrF and aap, whereas ST10002 had aap and icaABCDR. Notably, AZ39 possesses truncated ebh and sdrG and harbours a toxin-encoding gene. All isolates carry multiple antibiotic resistance genes conferring resistance to fosfomycin (fosB), ß-lactams (blaZ) and fluoroquinolones (norA). This study reveales a unique lineage for S. epidermidis and provides insight into the genetic basis of virulence and antibiotic resistance in transfusion-associated S. epidermidis strains.

The effectiveness of autologous platelet concentrates in prevention and treatment of medication-related osteonecrosis of the jaws: A systematic review.

The systematic review aims to answer the PICOS question: "Are the autologous platelet concentrates (APCs) an effective strategy in prevention and/or treatment of patients at risk of/affected by medication-related osteonecrosis of the jaws (MRONJ)?". A literature search was conducted via PubMed, MEDLINE, EMBASE, and CINAHL (January 2006 - September 2023). 30 articles were included, evaluating preventive (n = 8*) and treatment strategies (n = 23*). The risk of bias and quality of studies were assessed utilising ROB-2, ROBIN-1 and GRADE criteria. Meta-analysis was undertaken for eligible studies. The application of APCs demonstrated a statistically significant effectiveness in prevention of MRONJ in 86.13% (p < 0.001) but failed to achieve the same level of certainty in treatment of established MRONJ in 83.4% (p = 0.08). High levels of bias were identified; thus, the results should be interpreted with caution. More high quality prospective randomised controlled trials are needed to further evaluate the effectiveness of APCs in management of MRONJ.

Proliferation of psychrotrophic bacteria in cold-stored platelet concentrates.

BACKGROUND AND OBJECTIVES: Platelet concentrates (PC) are stored at 20-24°C to maintain platelet functionality, which may promote growth of contaminant bacteria. Alternatively, cold storage of PC limits bacterial growth; however, data related to proliferation of psychotrophic species in cold-stored PC (CSP) are scarce, which is addressed in this study. MATERIALS AND METHODS: Eight laboratories participated in this study with a pool/split approach. Two split PC units were spiked with ~25 colony forming units (CFU)/PC of Staphylococcus aureus, Klebsiella pneumoniae, Serratia liquefaciens, Pseudomonas fluorescens and Listeria monocytogenes. One unit was stored under agitation at 20-24°C/7 days while the second was stored at 1-6°C/no agitation for 21 days. PC were sampled periodically to determine bacterial loads. Five laboratories repeated the study with PC inoculated with lyophilized inocula (~30 CFU/mL) of S. aureus and K. pneumoniae. RESULTS: All species proliferated in PC stored at 20-24°C, reaching concentrations of ≤109 CFU/mL by day 7. Psychrotrophic P. fluorescens and S. liquefaciens proliferated in CSP to ~106 CFU/mL and ~105 CFU/mL on days 10 and 17 of storage, respectively, followed by L. monocytogenes, which reached ~102 CFU/mL on day 21. S. aureus and K. pneumoniae did not grow in CSP. CONCLUSION: Psychrotrophic bacteria, which are relatively rare contaminants in PC, proliferated in CSP, with P. fluorescens reaching clinically significant levels (≥105 CFU/mL) before day 14 of storage. Cold storage reduces bacterial risk of PC to levels comparable with RBC units. Safety of CSP could be further improved by implementing bacterial detection systems or pathogen reduction technologies if storage is beyond 10 days.

Evaluation of platelets componentized with the Reveos Automated Blood Processing System and stored for 7 days at room temperature in a non-Di(2-ethylhexyl) phthalate (DEHP) platelet pooling set.

BACKGROUND: Platelet concentrates (PCs) used for transfusion can be produced by apheresis or derived from whole blood (WB). The Reveos device is the first US Food and Drug Administration-approved automated blood processing system that can produce PCs. In this work, we evaluated the quality and function of Reveos-collected PCs stored for 7 days at room temperature. STUDY DESIGN AND METHODS: WB was collected from healthy donors and componentized on the day of collection (Fresh) or after an overnight hold (Overnight). PCs were produced (n = 7 Fresh; n = 6 Overnight), stored at room temperature in plasma, and evaluated on days 1 and 7 for quality metrics, platelet activation, clot formation, and aggregation response. RESULTS: Platelet count was comparable between Fresh and Overnight PCs. A drop in pH was reported in Fresh day 7 PCs (p < .001, vs. day 1) but not in Overnight. Overnight units displayed the lowest levels of P-selectin expression (p = .0008, vs. day 7 Fresh). Reduced clot strength and increased lysis were observed in both Fresh and Overnight units on day 7 (vs. day 1). Overnight-hold PCs resulted in the highest clot strength on day 7 (p = .0084, vs. Fresh). No differences in aggregation were reported between groups. CONCLUSION: Reveos-processed PCs produced from overnight-hold WB performed better in hemostatic function assays and displayed reduced activation compared to fresh WB-derived PCs, although both PC groups maintained platelet quality throughout storage. Utilization of overnight WB for PC preparation with Reveos holds promise as an alternative method of producing platelets for transfusion purposes.

Regenerative potential of platelet concentrates in chronic oral mucosal lesions.

Chronic oral mucosal diseases (COMDs) represent a significant challenge for clinicians and patients. They are commonly associated with chronic pain and negative effects on healing and patient's quality of life. Regenerative medicine including the use of biological autologous blood-derived substances (e.g., platelet concentrates [PCs]), has been reported to improve healing and reduce pain in orthopedic and maxillofacial surgeries as well as chronic oral mucosal diseases. In this review, we aim to describe the different types of PCs and their applications in the management of COMDs such as lichen planus, mucositis, pemphigus vulgaris, mucous membrane pemphigoid, and plasma cell mucositis, in terms of healing potential, pain control, and quality of life. Overall, PC applications seem to enhance healing and reduce pain in patients with COMDs. However, due to the small sample size and the lack of standardized clinical trials, further research is required to support these findings.

Histologic evaluation of edentulous alveolar ridge horizontal bone augmentations using a xenogeneic bone substitute and autologous platelet concentrates: a case series.

OBJECTIVES: This case series aimed to assess the efficacy of a novel horizontal ridge augmentation modality using histology. Combinations of "sticky bone" and tenting screws without autologous bone were used as augmentative materials. METHOD AND MATERIALS: Five individuals presenting healed, atrophic, partially edentulous sites that required horizontal bone augmentation before implant placement were enrolled. Patients underwent the same augmentation type and 5 months of postoperative reentry procedures. The first surgery served as implant site development, whereas the biopsy and corresponding implant placement were performed during reentry. The bone was qualitatively analyzed using histology and histomorphometry and quantitatively evaluated using CBCT. RESULTS: Four individuals healed uneventfully. Early wound dehiscence occurred in one case. Histology showed favorable bone substitute incorporation into the newly formed bone and intimate contact between de novo bone and graft material in most cases. Histomorphometry revealed an average of 48 ± 28% newly formed bone, 19 ± 13% graft material, and 33 ± 26% soft tissue components. The CBCT-based mean alveolar ridge horizontal increase was 3.9 ± 0.6 mm at 5 months postoperatively. CONCLUSIONS: The described augmentation method appears suitable for implant site development resulting in favorable bone quality according to histology. However, clinicians must accommodate 1 to 2 mm of resorption in augmentative material width at the buccal aspect.

Platelet Concentrates Preconditioning of Mesenchymal Stem Cells and Combined Therapies: Integrating Regenerative Strategies for Enhanced Clinical Applications.

This article presents a comprehensive review of the factors influencing the efficacy of mesenchymal stem cells (MSCs) transplantation and its association with platelet concentrates (PCs). It focuses on investigating the impact of PCs' composition, the age and health status of platelet donors, application methods, and environmental factors on the outcomes of relevant treatments. In addition, it delves into the strategies and mechanisms for optimizing MSCs transplantation with PCs, encompassing preconditioning and combined therapies. Furthermore, it provides an in-depth exploration of the signaling pathways and proteomic characteristics associated with preconditioning and emphasizes the efficacy and specific effects of combined therapy. The article also introduces the latest advancements in the application of biomaterials for optimizing regenerative medical strategies, stimulating scholarly discourse on this subject. Through this comprehensive review, the primary goal is to facilitate a more profound comprehension of the factors influencing treatment outcomes, as well as the strategies and mechanisms for optimizing MSCs transplantation and the application of biomaterials in regenerative medicine, offering theoretical guidance and practical references for related research and clinical practice.

Differences between first- and second-generation autologous platelet concentrates.

Autologous platelet concentrates (APCs) applied alone or combined with other biomaterials are popular bioactive factors employed in regenerative medicine. The main biological rationale of using such products is to concentrate blood-derived growth factors and cells into the wound microenvironment to enhance the body's natural healing capacity. First-generation APC is represented by platelet-rich plasma (PRP). While different protocols have been documented for PRP preparation, they overall consist of two cycles of centrifugation and have important limitations related to the use of an anticoagulant first and an activator afterward, which may interfere with the natural healing process and the release of bioactive molecules. The second generation of platelet concentrates is represented by leukocyte and platelet-rich fibrin (L-PRF). L-PRF protocols involve a single centrifugation cycle and do not require the use of anticoagulants and activators, which makes the preparation more straight forward, less expensive, and eliminates potential risks associated with the use of activators. However, since no anticoagulant is employed, blood undergoes rapid clotting within the blood collection tube; hence, a timely management of L-PRF is crucial. This review provides an overview on the most documented protocols for APC preparations and critically discusses the main differences between first- and second-generation APCs in terms of cell content, protein release, and the formation of a 3D fibrin network. It appears evident that the inconsistency in reporting protocol parameters by most studies has contributed to conflicting conclusions regarding the efficacy of different APC formulations and has significantly limited the ability to interpret the results of individual clinical studies. In the future, the use of a standardized classification system, together with a detailed reporting on APC protocol parameters is warranted to make study outcomes comparable. This will also allow to clarify important aspects on the mechanism of action of APCs (like the role of leukocytes and centrifugation parameters) and to optimize the use of APCs in regenerative medicine.

From Basic Science to Clinical Practice: A Review of Current Periodontal/Mucogingival Regenerative Biomaterials.

Periodontitis is a dysbiosis-driven inflammatory disease affecting the tooth-supporting tissues, characterized by their progressive resorption, which can ultimately lead to tooth loss. A step-wise therapeutic approach is employed for periodontitis. After an initial behavioral and non-surgical phase, intra-bony or furcation defects may be amenable to regenerative procedures. This review discusses the regenerative technologies employed for periodontal regeneration, highlighting the current limitations and future research areas. The search, performed on the MEDLINE database, has identified the available biomaterials, including biologicals (autologous platelet concentrates, hydrogels), bone grafts (pure or putty), and membranes. Biologicals and bone grafts have been critically analyzed in terms of composition, mechanism of action, and clinical applications. Although a certain degree of periodontal regeneration is predictable in intra-bony and class II furcation defects, complete defect closure is hardly achieved. Moreover, treating class III furcation defects remains challenging. The key properties required for functional regeneration are discussed, and none of the commercially available biomaterials possess all the ideal characteristics. Therefore, research is needed to promote the advancement of more effective and targeted regenerative therapies for periodontitis. Lastly, improving the design and reporting of clinical studies is suggested by strictly adhering to the Consolidated Standards of Reporting Trials (CONSORT) 2010 statement.

Effectiveness of Advanced Platelet-Rich Fibrin on Postoperative Sequelae for Impacted Mandibular Third Molar Surgery: A Prospective Study.

Introduction Impacted third molar extraction is frequently removed surgically by maxillofacial surgeons, which is mostly associated with postoperative sequelae like pain and swelling. It is essential to minimize the complications and enhance wound healing in the extracted socket of the third molar. Hence, this study aimed to assess the efficiency of advanced platelet-rich fibrin (A-PRF) in wound healing and reducing pain after surgical extraction of the impacted mandibular third molar (IMTM). Materials and methods Thirty healthy patients who have been diagnosed with Pell and Gregory class II IMTM were included in this study. In the study group, which comprises 15 patients, extraction sockets were filled with A-PRF extract. In the control group, no material was placed in the extraction sockets. The pain was assessed preoperative and on the third and seventh postoperative days using a visual analog scale (VAS). Wound healing was assessed on the third and seventh postoperative days using a modified laundry scale. SPSS for Windows was used for data analysis. Categorical data was compared between the groups using the Chi-square test. P-value less than 0.05 was considered as statistically significant. Results The study population's mean age was 25.67 ± 2.4 years. Nineteen patients were male, and 11 patients were female. Differences in mean pain scores between the groups were not statistically significant both on the third postoperative day (p=0.59) and the seventh postoperative day (p=0.33). During the seventh day postoperative day, the study group exhibited better wound healing compared to the control group and the results were statistically significant (p=0.01). Conclusion A-PRF is a simple and effective method of reducing postoperative sequela by promoting wound healing after surgical extraction of IMTM. It has the advantage of less chance of allergic and anaphylactic reactions, unlike their predecessor platelet concentrates.

APCs in sinus floor augmentation.

After tooth loss in the posterior area of the maxilla, sinus floor elevation is often required to compensate the vertical bone loss due to sinus pneumatization. This narrative review reports on the potential benefits of autologous platelet concentrates (APCs) during this procedure. As for transcrestal approach, APCs have been used as "sole" substitute/graft. However, because of the low number of clinical trials available with PRGF, and even none for PRP, no definitive conclusions can be made regarding their efficacy. The number of studies on the use of L-PRF were outnumbered indicating good feasibility for vertical bone gain, with a high implant survival rate and a low degree of complications. PRP and PRGF have not been studied as a "single/sole" substitute for a one-stage lateral window approach, probably because of the weak physical characteristics of the membranes. L-PRF alone appears to be a predictable grafting material for lateral maxillary sinus grafting and a reduced RBH should not be considered as a risk factor. Compared to a "standard" bone substitute L-PRF shows slightly less vertical bone gain (consider enough membrane application and use of bony window as new sinus floor roof over the implant apices), enhanced early resorption (first 6 months after application), but a similar stable bone gain afterward. For a two-stage lateral window approach, APCs "alone" cannot be recommended, due to their weak withstand to the sinus pneumatization forces. APCs combined with bone substitutes seem to accelerate bone formation, without any additional benefits on the long-term new bone gain. The use of L-PRF membranes for the treatment of perforations appears to be an effective treatment option, but further clinical studies are needed to confirm this. Even though the abovementioned statements are based on large numbers of studies, additional RCTs comparing APCs with different types of grafting procedures for sinus elevation are needed.