Introduction Chronic non-healing ulcers are defined as a discontinuity or break in the integrity of skin that is not healing in a reasonable period of time due to an underlying systemic etiology. Despite using conventional initial treatment and many other available dressing options, such wounds are difficult to completely heal, thus affecting the progress of rehabilitation measures and compromising functional improvement and quality of life. Materials and methods In this case series, platelet-rich fibrin (PRF) was applied to eight wounds from six patients. The patients included had various etiologies (including spinal cord injury, peripheral vascular disease, Guillain-Barré syndrome, and diabetic foot ulcer) with chronic non-healing wounds over different anatomical locations on the body. Pressure ulcer scale for healing (PUSH) score, surface area, and volume of the wounds were evaluated and monitored weekly after PRF dressing. We have applied PRF every week. On average, two PRF dressings were applied, the maximum being three applications. Results The maximum healing rate in terms of PUSH score was observed to be 3.84% per day, and the minimum was 1.19% per day. The maximum healing rate in terms of surface area was observed to be 5.89% per day, and the minimum was 1.78% per day. Three of the wounds showed complete closure. The maximum follow-up period was 10 weeks. The percentage mean Functional Independence Measure (FIM) improvement was calculated to be 15.87% ± 14.04 during the course of hospitalization after PRF application. Conclusion Based on the results, we can conclude that PRF showed accelerated improvement in the healing of chronic non-healing ulcers of various etiologies at different anatomical locations. It has proven to be a safe and effective method, thereby improving their quality of life and functional independence in performing activities of daily living. To our knowledge till date, no other study in a rehabilitation setting has been done on patients having non-healing ulcers due to various etiologies and at different anatomical locations.

BACKGROUND: External Inflammatory Root Resorption (EIRR) is a significant complication that can occur following traumatic dental injuries, with a prevalence of approximately 18%. Most cases occur during the early stage of the mixed dentition. Specifically, EIRR occurs in approximately 5-8% of luxation injuries, 30% of replanted teeth following avulsion, and 38% of intruded teeth. Conventional methods for addressing EIRR in immature teeth pose several challenges. This often requires numerous dental visits where Ledermix® and calcium hydroxide are used, which may significantly prolong the treatment. Additionally, the effect of prolonged use of calcium hydroxide medication in the root canal is debatable. Recent publications have highlighted the ability of regenerative endodontic treatment (RET) to effectively stop and repair external inflammatory root resorption (EIRR) in a relatively brief time, yielding impressive results. Nevertheless, the underlying mechanism responsible for this effect remains unclear.
METHODS: A hypothesis is proposed and drawn from existing data, explaining the mechanism by which RET triggers alterations in the root dimensions of necrotic immature teeth, facilitating continuous root maturation. The hypothesis suggests that bioactive molecules, including growth factors, might be able to penetrate the denuded dentin, reach the resorbed area, and attract stem cells from the surrounding periodontal ligament (PDL) and adjacent bone, leading to the arrest of the resorption process.
RESULTS: This recruitment may trigger repair mechanisms, ultimately resulting in the coverage of the denuded dentin with a new layer of PDL, cementoid, and cementum.
CONCLUSIONS: A hypothesis of the potential mechanism in which RET may arrest EIRR is presented along with a case report.

Platelet-rich fibrin (PRF), originally used to support soft tissue healing, is also considered a therapeutic option for treating oral lichen planus and leukoplakia. The progression from the two premalignant lesions to the aggressive malignant oral squamous cell carcinoma involves an inflammatory process linked to chemokine expression. Thus, there is a rationale for studying how PRF modulates the expression of chemokines in oral squamous carcinoma cells. To this aim, we expose the oral squamous carcinoma cell line HSC2 to IL1β and TNFα either alone or in the presence of lysates obtained from solid PRF membranes. We report here that in HSC2 cells, PRF lysates significantly reduce the forced transcription of chemokines, e.g., CXCL1, CXCL2, CXCL8, CXCL10, and CCL5. Moreover, PRF lysates attenuate the nuclear translocation of p65 in HSC2 oral epithelial cells when exposed to IL1β and TNFα. PRF lysates further reduce chemokine expression provoked by poly:IC HMW. Even though less pronounced, PRF lysates reduce IL1β- and TNFα-induced chemokine expression in TR146 cells. In primary oral epithelial cells, however, PRF lysates increase the basal expression of CXCL1, CXCL2 and CXCL8. Thus, PRF can exert a biphasic effect on chemokine expression in oral squamous cell carcinoma cell lines and primary oral epithelial cells. These findings suggest that PRF may reduce inflammation in a malignant environment while provoking an immunological response in healthy oral epithelium.

Our previous clinical observations showed that platelet rich fibrin (PRF) can be used to deliver antibiotics to attenuate postoperative complications after unilaterally impacted mandibular third molar surgery (IMTMS). In order to begin understanding the mechanism involved in the beneficial in vivo effects of PRF-mediated delivery of antibiotics, in vitro studies were performed, which showed that PRF preparations containing amoxicillin/clavulanic acid or clindamycin significantly inhibited the growth of S. aureus bacteria. In our previous study, comparisons were made between control and treated groups. However, since variations among individual patients could possibly affect the results, the current study included patients with bilaterally symmetric impacted mandibular third molars, allowing us to compare control and antibiotic treatment within each patient. The effects of PRF preparations containing amoxicillin/clavulanic acid or clindamycin on IMTMS was tested in 60 clinical cases. Antibiotic-injected PRF treatment after bilaterally IMTMS resulted in significantly reduced pain, less use of analgesics, and reduced swelling and trismus compared to the control group (PRF without antibiotics) confirming our previous results after unilaterally IMTMS. The in vitro results support the hypothesis that in vivo delivery of antibiotics using PRF produces therapeutic effects after IMTMS by attenuating bacterial infection and inflammation.

This case report explores the application of platelet-rich fibrin (PRF) as an autologous biomaterial in the surgical management of a periapical cyst in an 18-year-old female patient. The patient presented with pain, discoloration, and swelling in the maxillary left central incisor region, indicative of an asymptomatic periapical lesion associated with a history of trauma. Despite initial endodontic treatment with calcium hydroxide, the lesion persisted, necessitating surgical intervention. PRF, prepared from the patient\'s blood, was utilized during periapical surgery to promote healing and tissue regeneration. The surgical procedure included enucleation of the cyst, apicoectomy, and retrograde filling with Biodentine. Clinical and radiographic assessments at follow-up visits (three, six, and nine months post-surgery) revealed successful healing with no signs of inflammation or discomfort. The use of PRF demonstrated favorable outcomes in enhancing wound healing and maintaining a favorable environment for tissue remodeling. This case underscores the potential of PRF as an effective biomaterial in periapical surgery, advocating for its integration into dental therapeutic strategies for its regenerative properties and cost-effectiveness.

BACKGROUND: This clinical study investigates platelet-rich fibrin\'s (PRF) impact on dental implant stability, addressing global oral health challenges and limitations of traditional methods. Emphasizing osseointegration\'s pivotal role, the study explores PRF\'s potential in enhancing implant stability, assessing it through resonance frequency analysis (RFA) and implant stability quotient (ISQ). The hypothesis suggests PRF may improve both primary and secondary stability, aiming to uncover clinical benefits in dental implant procedures Materials and methods: The study involved 24 subjects from the Department of Periodontics outpatient clinics with a meticulously designed methodology. This included a pre-surgical protocol with oral prophylaxis, impressions, and cone-beam computed tomography (CBCT) analysis. PRF preparation utilized a minimally invasive venipuncture technique. Implant placement followed a two-stage surgical protocol, assessing primary stability with MEGA ISQ (Ostell). Post-surgery, patients received instructions and underwent recall for secondary stability after three months. Clinical parameters such as plaque index (PI), gingival index (GI), implant probing pocket depth (IPPD), sulcus bleeding index (SBI), and implant stability (IS) were systematically recorded. Robust statistical analyses, using IBM SPSS Statistics for Windows v20.0 (IBM Corp., Armonk, USA) software, incorporated Mann-Whitney U and Wilcoxon signed-rank tests for group and within-time point comparisons, with a significance level of p<0.05. This comprehensive study yields nuanced insights into the impact of PRF and implant procedures on key clinical parameters, contributing significantly to the field.
RESULTS: This study compared dental implants with and without PRF in 24 patients. Both groups showed significant improvements in the PI, GI, and SBI. The PRF group exhibited higher IS in the third and sixth months, while IPPD was lower in the PRF group in the sixth month.
CONCLUSIONS: The findings of the study highlight a positive impact on implant stability contributing to better implant outcomes.

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.

OBJECTIVE: To evaluate the efficacy of platelet-rich fibrin (PRF) as an adjunct to scaling and root planing (ScRp) for healing shallow periodontal pockets.
METHODS: Twelve patients with periodontitis were enrolled in this split-mouth, randomized clinical trial. A total of 24 shallow periodontal pockets (4-6 mm) were treated by either ScRp alone (control) or PRF (test). Clinical attachment loss (CAL), probing pocket depth (PPD), bleeding on probing (BOP), and plaque index (PLI), as well as platelet-derived growth factor-BB (PDGF-BB) by enzyme-linked immunosorbent assay (ELISA) in gingival crevicular fluid (GCF) were measured at baseline and at 1- and 3-month follow-up visits.
RESULTS: At 1- and 3-month follow-up visits, greater CAL gains (2.6 ± 0.25 mm and 3.26 ± 0.31 mm, respectively) and PPD reductions (2.58 ± 0.38 and 3.31 ± 0.39 mm, respectively) were observed in the test group compared to those in controls (CAL gain of 1.01 ± 0.49 mm and 1.43 ± 0.48 mm; PPD reduction of 1.1 ± 0.55 and 1.37 ± 0.49 mm, respectively). In addition, the increase in PDGF-BB in GCF in the test group (724.5 ± 186.09 pg/μl and 1957.5 ± 472.9 pg/μl) was significantly greater than that in controls (109.3 ± 24.07 and 614.64 ± 209.3 pg/μl) at 1- and 3-month follow-up visits, respectively.
CONCLUSIONS: The noninvasive use of PRF as an adjunct to ScRp successfully improved clinical periodontal parameters and might contribute to increased PDGF-BB in GCF.

This case series evaluated use of injectable platelet rich fibrin (termed i-PRF+) for the treatment of female pattern hair loss (FPHL). Eleven individuals underwent 3-monthly intradermal injections of i-PRF+ using a mesotherapy gun. The mean number of hair follicles containing hairs per unit area improved at 3- and 6-months follow-up (p < .001), and all participants had a negative hair pull test. Hair volume and thickness, and patient-reported outcome scores also improved at follow-up (p < .001). Adverse effects were minor and self-limited. A series of three i-PRF+ injection sessions were effective for the treatment of FPHL, as shown by improved hair analysis parameters and patient self-assessment scores.

The population receptive field method, which measures the region in visual space that elicits a BOLD signal in a voxel in retinotopic cortex, is a powerful tool for investigating the functional organization of human visual cortex with fMRI (Dumoulin & Wandell, 2008). However, recent work has shown that population receptive field (pRF) estimates for early retinotopic visual areas can be biased and unreliable, especially for voxels representing the fovea. Here, we show that a \'log-bar\' stimulus that is logarithmically warped along the eccentricity dimension produces more reliable estimates of pRF size and location than the traditional moving bar stimulus. The log-bar stimulus was better able to identify pRFs near the foveal representation, and pRFs were smaller in size, consistent with simulation estimates of receptive field sizes in the fovea.