Fatal asphyxia due to large laryngeal granuloma.

Laryngeal granuloma, vocal process granuloma, or post-intubation granuloma are benign, inflammatory lesions of the arytenoid cartilage vocal process. The etiology of laryngeal granulomas is multifactorial, such as chronic irritation due to endotracheal intubation, vocal cord injury or trauma, and gastroesophageal reflux disease. They can arise postoperatively after mucosal injury due to orotracheal intubation. Clinical manifestations include voice change and dyspnea, which may start one to four months after extubation and may rarely lead to asphyxia. We presented a case of death due to glottic granuloma occurring after a surgical procedure to remove a laryngeal polyp attributed to previous laryngeal injuries by multiple intubations.

Platelet rich fibrin augmented tympanoplasty versus cartilage tympanoplasty: a randomized clinical trial.

OBJECTIVES: The aim of the current study was to evaluate the efficacy of PRF-augmented fascia tympanoplasty versus cartilage tympanoplasty in repair of large TM perforations. METHODS: This randomized clinical trial included 156 patients with dry large tympanic membrane perforations. Patients were randomly allocated into 2 groups, cartilage tympanoplasty group (n = 77) and platelet rich fibrin (PRF) augmented tympanoplasty group (n = 79). Graft take rates, hearing outcomes, operative time, and postoperative complications were documented and compared. RESULTS: Graft take rate was 96.1% in the cartilage group and 93.7% PRF group with no statistically significant difference. Operative time was significantly longer in the cartilage group. No differences in the hearing outcomes and postoperative complications were reported. CONCLUSION: Application of PRF on the fascia in tympanoplasty promotes healing of the tympanic membrane. PRF is safe, cheap, readily available, and easily prepared and applied. It increases the success rates of large tympanic membrane perforations without the need for cartilage grafts.

Salvaging the second molar with platelet-rich fibrin and photobiomodulation (970 nm diode laser) following third molar extraction.

Second molars are more susceptible to periodontitis when present adjacent to periodontally hopeless third molars. It is crucial to restore the health of the second molar and to prevent a dry socket after third molar extraction. To ensure complete eradication of infection along with regeneration, mere nonsurgical periodontal therapy might be inadequate. Thus, in this case report, high-level laser therapy (HLLT), advanced-platelet-rich fibrin (A-PRF), and low-level laser therapy (photobiomodulation [PBM]) were adapted to obtain a synergistic effect. HLLT was accomplished for decontamination and clot stabilization following the third molar extraction. Further, A-PRF was placed and irradiated with PBM on 3rd, 7th, 15th, and 21st days, postoperatively. There was reduced clinical probing depth and gain in clinical attachment level with a significant radiographic bone fill distal to second molar at 3 months follow-up. This combined use of HLLT, and PBM along with PRF could be a reliable treatment approach for regeneration, particularly in acute infections.

Establishing Expectancy Values for Fibrin Monomer in Uncomplicated Pregnancy.

Background During pregnancy, a physiological increase of molecular activation markers (MAM) of hemostasis such as prothrombin fragments 1 + 2, thrombin-antithrombin complex, and D-dimers (DD) occurs. Therefore, monitoring MAM levels during pregnancy to evaluate the risk of venous thromboembolism (VTE) may be unreliable; nevertheless, DD analysis in pregnancy is widely performed. In contrast to DD, fibrin monomer (FM) levels have been reported to remain stable during pregnancy. Objectives The main aim of this study was to define the expected range for FM levels in pregnant outpatients. In addition, we examined the impact of the individual VTE risk, as calculated by the pregnancy risk score of the Royal College of Obstetricians and Gynaecologists (RCOG), as well as that of antithrombotic treatment on FM levels. Methods A total of 342 pregnant women seen at our hemostasis unit were included throughout 350 pregnancies in 899 samples. Results Low-risk thrombophilia, but not the RCOG score itself, was found to influence all MAM levels, whereas antithrombotic treatment had only an impact on DD. For FM, a reference range could be calculated irrespective of the pregnancy term, in contrast to other MAMs, which fluctuated throughout pregnancy. Conclusions Our findings suggest a stronger impact of inherited thrombophilia on hemostasis activity during pregnancy as compared with acquired or other predisposing thrombophilic risk factors. FM levels showed a marginal increase during pregnancy in contrast to other MAM and remain a potential candidate to improve the laboratory assessment of VTE risk during pregnancy. Further prospective studies in pregnant patients with suspicion of VTE are needed.

Antimicrobial peptide-fibrin glue mixture for treatment of methicillin-resistant Staphylococcus aureus-infected wounds.

Aim: This study was conducted to investigate the effect of fibrin glue-CM11 antibacterial peptide mixture (FG-P) on the healing of infected wounds in vivo. Materials & methods: We formulated a mixture of FG-P and evaluated its antimicrobial activity in vitro against multidrug-resistant (MDR) bacteria involved in wound infection as well as its healing effect on wound infected by methicillin-resistant S. aureus (MRSA) in vivo. Results: The peptide had an MIC of 8 µg/ml against all bacteria isolates. Growth inhibition zones were evident for FG-P compared with FG. The in vivo study showed that the FG-P could be significantly effective in healing the MRSA-infected wound. Conclusion: The use of FG-P mixture is a very suitable option for treating infected wounds.

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Ascites microenvironment conditions the peritoneal pre-metastatic niche to promote the implantation of ovarian tumor spheroids: Involvement of fibrinogen/fibrin and αV and α5ß1 integrins.

At least one-third of patients with epithelial ovarian cancer (OC) present ascites at diagnosis and almost all have ascites at recurrence especially because of the propensity of the OC cells to spread in the abdominal cavity leading to peritoneal metastasis. The influence of ascites on the development of pre-metastatic niches, and on the biological mechanisms leading to cancer cell colonization of the mesothelium, remains poorly understood. Here, we show that ascites weakens the mesothelium by affecting the morphology of mesothelial cells and by destabilizing their distribution in the cell cycle. Ascites also causes destabilization of the integrity of mesothelium by modifying the organization of cell junctions, but it does not affect the synthesis of N-cadherin and ZO-1 by mesothelial cells. Moreover, ascites induces disorganization of focal contacts and causes actin cytoskeletal reorganization potentially dependent on the activity of Rac1. Ascites allows the densification and reorganization of ECM proteins of the mesothelium, especially fibrinogen/fibrin, and indicates that it is a source of the fibrinogen and fibrin surrounding OC spheroids. The fibrin in ascites leads to the adhesion of OC spheroids to the mesothelium, and ascites promotes their disaggregation followed by the clearance of mesothelial cells. Both αV and α5ß1 integrins are involved. In conclusion ascites and its fibrinogen/fibrin composition affects the integrity of the mesothelium and promotes the integrin-dependent implantation of OC spheroids in the mesothelium.

Efficiency Analysis of Hemostatic Agents in Drainless Neck Surgery: Cellulose-Based Versus Liquid Fibrin Sealants.

PURPOSE:  Using liquid fibrin sealants has once again questioned the benefit of drain placement in head and neck operations. Cellulose-based hemostats offering different hemostasis mechanisms have scarcely been investigated in drainless neck surgeries. This study aimed to evaluate whether liquid fibrin sealant offers any advantage over cellulose-based hemostats in various head and neck surgeries. METHODS: A prospective trial of patients who underwent various neck surgeries between 2020 and 2022. Baseline characteristics and postoperative outcomes were compared between the drain-placed and the drainless groups, with the latter sub-categorized into three groups: fibrin sealant, cellulose-based hemostats, and a combination of both. RESULTS: A total of 119 patients were included (63 thyroidectomies, 40 parathyroidectomies, and 16 sialoadenectomies). Fifty eight had a drain placed and 61 had no drain. In the drainless group, 23 patients received cellulose-based absorbable hemostats (SURGICEL®/ FIBRILLAR™); 18 patients had fibrin sealants (EVICEL®/TachoSil®/TISSEEL); in 16, a combination of both was used; and in four patients, no hemostatic agent was used. Three (5%) of the 61 drainless patients developed a seroma compared to one (2%) seroma in the drain-placed patients. No advantage was demonstrated using a combination of FIBRILLAR™ with a fibrin sealant nor for any used separately. Drain placement delayed patient discharge by at least one day compared to the group without a drain (p < 0.001). CONCLUSION: Drain placement offered a minor advantage in the postoperative course reducing rates of seroma formation, while delaying patient discharge by at least one day. There was no advantage in using a specific hemostatic agent over the other.

The efficacy of Platelet and Leukocyte Rich Fibrin (L-PRF) in the healing process and bone repair in oral and maxillofacial surgeries: a systematic review.

INTRODUCTION: The search to optimize the healing and bone repair processes in oral and maxillofacial surgeries reflects the constant evolution in clinical practice, driven by the demand for increasingly satisfactory results and the need to minimize postoperative complications. OBJECTIVE: To evaluate the efficacy of Platelet and Leukocyte Rich Fibrin (L-PRF) in the healing and bone repair process in oral and maxillofacial surgeries. MATERIALS AND METHODS: The systematic review protocol for this study included the definition of the research question, the domain of the study, the databases searched, the search strategy, the inclusion and exclusion criteria, the types of studies to be included, the measures of effect, the methods for screening, data extraction and analysis, and the approach to data synthesis. Systematic literature searches were carried out on Cochrane databases, Web of Science, PubMed, ScienceDirect, Embase and Google Scholar. RESULTS: The strategic search in the databases identified 1,159 studies. After removing the duplicates with the Rayyan© software, 946 articles remained. Of these, 30 met the inclusion criteria. After careful evaluation based on the inclusion and exclusion criteria, 8 studies were considered highly relevant and included in the systematic review. CONCLUSION: Platelet and Leukocyte Rich Fibrin (L-PRF) has a positive effect on the healing process and bone repair in oral and maxillofacial surgeries.

Occlusal trauma aggravates periodontitis through the plasminogen/plasmin system.

OBJECTIVES: Periodontitis is a common oral disease that is aggravated by occlusal trauma. Fibrin is a protein that participates in blood clotting and is involved in several human diseases. The deposition of fibrin in periodontal tissues can induce periodontitis, while mechanical forces may regulate the degradation of fibrin. Our study investigated how occlusal trauma aggravating periodontitis through regulating the plasminogen/plasmin system and fibrin deposition. MATERIALS AND METHODS: This study included 84 C57BL/6 mice in which periodontitis was induced with or without occlusal trauma. Micro-computed tomography was used to assess bone resorption. Fibrin, fibrinogen, plasminogen, plasmin, tissue plasminogen activator (t-PA), and urokinase plasminogen activator (u-PA) levels were measured using Frazer-Lendrum staining, quantitative reverse transcription polymerase chain reaction, enzyme-linked immunosorbent assay, western blotting, immunofluorescence staining, and immunohistochemistry staining. RESULTS: Occlusal trauma aggravated inflammation and bone resorption. The periodontitis group showed significant fibrin deposition. Occlusal trauma increased fibrin deposition and neutrophil aggregation. The periodontitis with occlusal trauma group had decreased fibrinogen, t-PA, and u-PA expression and plasmin and fibrin degradation product levels, as well as increased plasminogen levels. CONCLUSION: Occlusal trauma promotes excessive fibrin deposition by suppressing the plasminogen/plasmin system, thus exacerbating periodontitis.

DR-70 (fibrinogen-fibrin degradation products) as a prognostic biomarker in dogs with neoplasms.

Fibrinogen-fibrin degradation products (DR-70) are derived from tumor cells or metastases. Our previous study reported the diagnostic values in dogs with tumors, but no research has yet to be conducted to establish DR-70 as a prognostic marker. Herein, we investigated changes in DR-70 concentrations and disease courses in dogs with tumors. Overall survival time (OST) analysis was performed in 195 dogs with tumors, stratified with a recommended cut-off (1.514 µg/mL). Continual DR-70 measurements were performed during the medical interventions of 27 dogs with neoplasms. Clinical conditions and medical records were retrospectively reviewed. According to a cut-off value, dogs with plasma DR-70 concentrations above 1.514 µg/mL had shorter survival rates than those with concentrations below this threshold. In cases with complete or partial remission in response to treatment, the DR-70 concentration was decreased compared with that at the first visit, whereas it was increased in patients with disease progression. Our study suggested that changes in DR-70 concentration can be used as a prognostic biomarker for canine neoplasms. Furthermore, increased plasma DR-70 levels might be associated with shorter survival, and DR-70 concentrations may reflect responses to medical intervention.

The use of Fibrin Sealants in Reducing Drain Output in Abdominoplasty: Is it Useful?

Background: Abdominoplasty is a common surgical procedure in which excess abdominal skin and fat are reduced to improve body contouring. Fibrin sealant has been proposed to reduce postsurgical bleeding and exudation. In this study, we evaluated whether there was a significant statistical difference in surgical output between the use of fibrin glue and its nonuse in abdominoplasty surgery, specifically in reducing bleeding and exudation. Material and methods: A retrospective chart review of 68 postbariatric abdominoplasty patients (58 females, 10 males) was performed. We divided the patients into Group A (30 cases, 44%), in which we used fibrin sealant, and Group B (38 cases, 56%), in which we did not use fibrin glue. We calculated the total amount of liquid in suction drainages until the day of their removal. Statistical analysis included the independent t-test with a significance level of 0.05. Results: The average drainage output in Group A was 620.0 ± 375.0 mL, whereas in Group B, it was 500.0 ± 290.0 mL. Results indicate an insignificant correlation between the use of fibrin glue and the amount of liquid in the surgical drains (t = 1.52, p = 0.13). The result is not significant at p <.05 according to the independent t-test. Conclusion: The use of fibrin sealant surely has a high value in all surgical branches to reduce postoperative complications, but in our study, we did not find any advantages in its use for reducing surgical drain output in abdominoplasty patients.

Evaluation of intra-articular injection of injectable platelet-rich fibrin, anterior repositioning splint and arthrocentesis in treatment of temporomandibular joint internal derangement.

The current research paper was designed to assess the impact of an intra-articular injection of injectable platelet-rich fibrin (I-PRF) following arthrocentesis and the use of an anterior repositioning splint (ARS) as a proposed treatment approach for addressing symptomatic internal derangement of the temporomandibular joint (TMJ). This study comprised thirty patients who presented with bilateral disc displacement without reduction. The patients were evenly distributed into two groups: Group I underwent treatment involving ARS and arthrocentesis alone, while Group II underwent treatment with ARS, arthrocentesis, and the injection of I-PRF. Clinical assessment of all patients was done postoperatively in the following intervals; first week, first month, third month, and six months for maximum mouth opening (MMO), right and left lateral excursion, and pain score. Magnetic resonance imaging (MRI) assessment for all joints was done at the sixth month postoperatively. Both groups demonstrated improvement in MMO, lateral excursion, and pain. Significant statistical differences were observed in the mean values of MMO and Visual Analogue Scale (VAS), favouring the I-PRF group. MRI postoperatively showed no significant changes in disk position or morphology at the end of the sixth month. Administering an intra-articular I-PRF injection subsequent to arthrocentesis demonstrates effectiveness as a treatment approach for alleviating the signs and symptoms associated with internal derangement of the TMJ.

Effectiveness of Injectable Platelet-Rich Fibrin Therapy in Alopecia and Facial Rejuvenation: A Systematic Review.

Platelet-rich fibrin (PRF) has gained attention in regenerative medicine for its potential to enhance tissue repair and regeneration. Its application in dermatology, particularly for treating alopecia and facilitating facial rejuvenation, is of significant interest but requires systematic evaluation. This review aims to systematically assess the effectiveness of injectable PRF therapy in treating alopecia and facial rejuvenation procedures. We searched PubMed, Scopus, and Web of Science for studies published up to 2023 that involved injectable PRF for alopecia and facial rejuvenation. Eligible studies included prospective cohorts, original studies, case series, and retrospective studies that reported clinical outcomes. Key outcomes were improved hair growth for alopecia and skin texture, elasticity, and appearance for facial rejuvenation. Seven studies met the inclusion criteria, encompassing 130 patients. For alopecia, three studies reported a noticeable improvement in hair density and growth. For facial rejuvenation, four studies demonstrated moderate to significant improvements in skin texture and elasticity and a reduction in facial wrinkles and lines, confirmed by both subjective assessments and objective measurements such as VISIA® skin analysis. Injectable PRF therapy shows promise in treating androgenetic alopecia and enhancing facial esthetics, indicating its potential as an effective treatment option in regenerative dermatology. However, further research involving larger sample sizes, control groups, and longer follow-ups is required to validate these findings and establish standardized treatment protocols.

A cross-sectional study on non-infectious dysfunction of hemodialysis cuffed catheter.

Background: Dialysis cuffed catheter dysfunction results in inadequate dialysis, increased sepsis risk, and a shortened catheter life. It may be possible to prolong catheter function by identifying the causes of cuffed catheter dysfunction. Methods: This study was a cross-sectional descriptive study conducted in 2021-2022 on hemodialysis patients with jugular cuff catheters. The catheterizations were performed using the Seldinger technique and were confirmed by fluoroscopy. A 12-month follow-up was conducted with respect to the performance of the cuffed catheter. Results: A total of 123 patients underwent hemodialysis over 2 years via a cuffed catheter. Catheters were most commonly inserted into the right internal jugular vein, with lengths of 19 cm (tip to cuff). The rate of dysfunction of cuffed catheters was 27.6%. Catheter-related thrombosis was the most common cause in 10 cases (29.4%), followed by catheter tip fibrin sheath in 8 cases (23.5%) and catheter tip malposition in 8 cases (23.5%). Furthermore, 18 patients (52.94%) of cuffed catheter dysfunction occurred within 3 months of catheter placement, based on our study. The dysfunction of cuffed catheters on the left side 23 (67.64%) is more prevalent than the right side 11 (32.35%) (P=0.043); the malposition of catheter tips is more prevalent on the left side (P=0.023). Conclusion: Most commonly, cuffed catheter dysfunction is caused by thrombosis, fibrin sheath formation, and catheter tip malposition. Cuffed catheter failure can be reduced by carefully monitoring the catheter's path and tip position, searching for fibrin sheaths when investigating cuffed catheter failure, and preventing thrombotic events.

Efficacy of photobiomodulation following L-PRF application for recovery of mental nerve neurosensory disturbances caused by genioplasty: A randomized triple-blind clinical trial.

The present study assessed the efficacy of photobiomodulation (PBM) following leukocyte-platelet rich fibrin (L-PRF) application for recovery of mental nerve neurosensory disturbances (NSDs) caused by genioplasty. This randomized triple-blind split-mouth clinical trial was conducted on 20 female patients (40 quadrants) requiring genioplasty. In each patient, one random side of the mandible served as the intervention (laser), and the other side as the control group. After genioplasty and L-PRF application, the intervention side underwent GaAIAs diode laser irradiation (880 nm, 500 mW, 15 J/cm2, 0.5 cm2 spot size, continuous-wave). Each point was laser irradiated for 15 s. Unilateral extraoral PBM was performed at 1, 3, 7, 14, 21, and 28 days, postoperatively. Laser in off mode (sham laser) was used for the control side. A visual analog scale (VAS) was used for general sensitivity, and 2-point discrimination, directional discrimination, pain discrimination, and thermal discrimination tests were used to assess the neurosensory recovery at 2 days, 2 weeks, 4 weeks, and 2 months, postoperatively. Statistical analyses were performed using two-way repeated measures ANOVA, Bonferroni test, and generalized estimating equation (alpha = 0.05). Time had a significant effect on improvement of all sensory variables (P < 0.05). Neurosensory recovery was significantly better in the intervention than the control group at all time points according to the two-point discrimination test (P = 0.0135) and brush test (P = 0.025) results. The interaction effect of time and intervention was not significant on any dependent variable (P > 0.05). Application of L-PRF + PBM resulted in significantly greater sensorineural recovery according to the two-point discrimination and brush test results.

Socket Preservation Using Platelet-Rich Fibrin and Free Gingival Grafts.

OBJECTIVE: The present randomised controlled trial is based on the null hypothesis that there is no difference in crestal bone levels (CBLs) following socket preservation (SP) using platelet-rich fibrin (PRF) and free gingival graft (FGG). The aim was to evaluate CBLs following SP using PRF and FGG. METHODS: This study is a parallel-arm randomised controlled trial. Patients in the test and control groups underwent SP using PRF and FGG, respectively. Intraoral visual examination was performed to clinically assess signs of swelling, pus/abscess, and stability of sutures and graft. Self-rated postoperative pain was assessed after 1 week and 6 months using the visual analogue scale (VAS). At the 6-month follow-up, cone-beam computed tomography was performed to evaluate CBL in mesiodistal and buccolingual dimensions. The preoperative cone-beam computed tomographic images were superimposed with those taken at the 6-month follow-up to compare CBLs. Statistical comparisons were performed and level of significance was set at P < .05. RESULTS: The test and control groups each comprised 13 individuals with comparable ages. All teeth included in the test and control groups were located in the maxillary aesthetic zone. At the 1-week follow-up, VAS scores were higher in the control than in the test group (P < .01). At the 6-month follow-up, none of the participants reported self-rated pain. The change in buccolingual dimension was greater in the control group than in the test group (P < .05). CONCLUSIONS: Both FGG and PRF are effective techniques for SP; however, the latter technique is more effcacious in maintaining buccolingual dimensions of the extraction socket.

Artiss fibrin sealant for the fixation of autografts in pediatric burn care.

BACKGROUND: Traditional fixation of autografts in the treatment of burns involves the use of sutures and staples. A novel fibrin sealant, Artiss, has been introduced as an alternate method of fixation and has shown promising safety and efficacy results in the adult population. Our study assessed the effectiveness of fibrin sealant to secure autologous split thickness skin grafts (ASTSG) in the pediatric burn population. METHODS: We performed a retrospective cohort study of pediatric patients under 18 years of age who received autografting for the treatment of burns at our institution between 2017 and 2023. We compared ASTSG secured with fibrin sealant to those managed traditionally with sutures or staples. Outcomes of interest include the need for return trips to the operating room (OR), time to wound healing, graft take, and total time in the operating room. RESULTS: 83 patients underwent a total of 142 individual ASTSGs for management of unique body area injuries. 66.3 % were male, median age was 79 months, and scald was the most common mechanism of injury (41.0 %). Forty-five (39.5 %) traditionally affixed ASTSG required at least one return to the OR while only one (3.6 %) ASTSG secured with fibrin sealant required an additional return to the OR (p < 0.001). Graft take was similar in both groups (92.9 % for fibrin sealant vs. 93.9 % for traditional methods, p = 1). Time to wound healing was also similar: 16 vs. 15 days for fibrin glue and traditional methods, respectively (p = 0.23). CONCLUSION: Outcomes from autograft fixation with fibrin sealant were comparable to those treated with traditional methods, with a reduction in the need for return trips to the operating room. These data suggest that fibrin sealant is a suitable alternative to traditional fixation methods in pediatric autografting.

Dosimetry of [64Cu]FBP8: a fibrin-binding PET probe.

Purpose: This study presents the biodistribution, clearance and dosimetry estimates of [64Cu]Fibrin Binding Probe #8 ([64Cu]FBP8) in healthy subjects. Procedures: This prospective study included 8 healthy subjects to evaluate biodistribution, safety and dosimetry estimates of [64Cu]FBP8, a fibrin-binding positron emission tomography (PET) probe. All subjects underwent up to 3 sessions of PET/Magnetic Resonance Imaging (PET/MRI) 0-2 hours, 4h and 24h post injection. Dosimetry estimates were obtained using OLINDA 2.2 software. Results: Subjects were injected with ~400 MBq of [64Cu]FBP8. Subjects did not experience adverse effects due to the injection of the probe. [64Cu]FBP8 PET images demonstrated fast blood clearance (half-life = 67 min) and renal excretion of the probe, showing low background signal across the body. The organs with the higher doses were: the urinary bladder (0.075 vs. 0.091 mGy/MBq for males and females, respectively); the kidneys (0.050 vs. 0.056 mGy/MBq respectively); and the liver (0.027 vs. 0.035 mGy/MBq respectively). The combined mean effective dose for males and females was 0.016 ± 0.0029 mSv/MBq, lower than the widely used [18F]fluorodeoxyglucose ([18F]FDG, 0.020mSv/MBq). Conclusions: This study demonstrates the following properties of the [64Cu]FBP8 probe: low dosimetry estimates; fast blood clearance and renal excretion; low background signal; and whole-body acquisition within 20 minutes in a single session. These properties provide the basis for [64Cu]FBP8 to be an excellent candidate for whole-body non-invasive imaging of fibrin, an important driver/feature in many cardiovascular, oncological and neurological conditions.

Tooth Autotransplantation, Autogenous Dentin Graft, and Growth Factors Application: A Method for Preserving the Alveolar Ridge in Cases of Severe Infraocclusion-A Case Report and Literature Review.

Background: Tooth infraocclusion is a process in which a completely or partially erupted tooth gradually moves away from the occlusal plane. Submerged teeth can lead to serious complications. Treating teeth with infraocclusion is very challenging. One of the procedures allowing for the replacement of a missing tooth is autotransplantation. The aim of this paper is to review the literature on teeth autotransplantation, supported by a case report involving the autotransplantation of a third mandibular molar into the site of an extracted infraoccluded first mandibular molar, as well as the utilization of advanced platelet-rich fibrin (A-PRF) alongside autogenous dentin grafts for bone tissue regeneration. Methods: A severely infraoccluded first permanent right mandibular molar was extracted and then ground to obtain the dentin graft. A-PRF clots (collected from the patient's peripheral blood) were added to the autogenous dentin graft, to create the A-PRF membrane. An atraumatic extraction of the lower left third molar was performed and then it was transplanted into the socket of tooth no. 46. Immediately after transplantation, tooth no. 38 was stabilized with orthodontic bracket splints for 3 months. The patient attended regular follow-up visits within 12 months. Results: After one year, the patient did not report any pain. In the clinical examination, the tooth and surrounding tissues did not show any signs of infection. However, radiographically, cervical inflammatory resorption, unchanged pulp canal dimensions, absent root growth, periapical radiolucency, and lack of apical and marginal healing were observed. Reconstruction of the bone defect was obtained and the alveolar ridge of the mandible was preserved. Due to poor stability of the tooth and severe resorption, the tooth needed to be extracted. Conclusions: This study is designed to critically evaluate the efficacy of autotransplantation, the application of growth factors, and the integration of autogenous dentin grafts in remedying dental deficiencies resulting from reinclusion. We aim to point out the possible causes of treatment failure.

Immunoregulatory role of platelet derivatives in the macrophage-mediated immune response.

Background: Macrophages are innate immune cells that display remarkable phenotypic heterogeneity and functional plasticity. Due to their involvement in the pathogenesis of several human conditions, macrophages are considered to be an attractive therapeutic target. In line with this, platelet derivatives have been successfully applied in many medical fields and as active participants in innate immunity, cooperation between platelets and macrophages is essential. In this context, the aim of this review is to compile the current evidence regarding the effects of platelet derivatives on the phenotype and functions of macrophages to identify the advantages and shortcomings for feasible future clinical applications. Methods: A total of 669 articles were identified during the systematic literature search performed in PubMed and Web of Science databases. Results: A total of 27 articles met the inclusion criteria. Based on published findings, platelet derivatives may play an important role in inducing a dynamic M1/M2 balance and promoting a timely M1-M2 shift. However, the differences in procedures regarding platelet derivatives and macrophages polarization and the occasional lack of information, makes reproducibility and comparison of results extremely challenging. Furthermore, understanding the differences between human macrophages and those derived from animal models, and taking into account the peculiarities of tissue resident macrophages and their ontogeny seem essential for the design of new therapeutic strategies. Conclusion: Research on the combination of macrophages and platelet derivatives provides relevant information on the function and mechanisms of the immune response.