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Tissue engineering focuses on wound healing and tissue regeneration. Platelet-rich fibrin (PRF) is a fibrin matrix containing cytokines, growth factors and cells that are gradually released into the wound over time. This study aimed to evaluate the effect of PRF membranes on wound repair and microbial control in infected wounds. Skin wounds were performed on the dorsum of rats using a 6 mm diameter metal punch. The defects were randomly assigned into four groups (n = 12/each) accordingly to the treatment: G1, noninfected wound filled only with clot; G2, noninfected wound with PRF; G3, infected wound (S. aureus) without PRF; G4, infected wound (S. aureus) with PRF. After 7 and 14 days, macroscopic and histological analyses of the wounds were performed. Furthermore, the quantification of β-defensin in PRF was measured by ELISA. At 14 days, the groups with PRF (G2 and G4) had wound sizes significantly smaller than the original defects (6 mm) (p

The current study evaluated the healing of critical-size defects (CSD) created in rat calvaria treated with platelet concentrates produced by high-speed (Leukocyte- and Platelet-Rich Fibrin - L-PRF) and low-speed (Advanced Platelet-Rich Fibrin - A-PRF) protocols of centrifugation. Twenty-four rats were distributed into three groups: Control, L-PRF, and A-PRF. Five mm diameter CSD were created on the animals' calvaria. The defects of the L-PRF and A-PRF groups were filled with 0.01 ml of L-PRF and A-PRF, respectively. The control group defects were filled with a blood clot only. All animals were euthanized on the 35th postoperative day. Histomorphometric and microtomographic analyses were then performed. The L-PRF and A-PRF groups had significantly higher bone volume and neoformed bone area than those of the control group and lowered bone porosity values (p .05). No significant differences were observed between A-PRF and L-PRF groups for the analyzed parameters. Therefore, it can be concluded that i) L-PRF and A-PRF potentiated the healing of CSD in rat calvaria; ii) high and low-speed centrifugation protocols did not produce PRF matrices with different biological impacts on the amount of bone neoformation.

Lasers are increasingly utilized in the non-surgical treatment of periodontal disease. The aim of the present systematic review with meta-analysis was to investigate the combination use of Nd:YAG and Er:YAG laser therapy in the treatment of severe periodontitis. A systematic review of the literature including searches in PubMed/Medline, Cochrane Library, Google Scholar, and Grey Literature databases, as well as manual searches, was performed until November 1, 2021. Only studies a combination of lasers during non-surgical treatment of pockets ≥ 6mm were included. The eligibility criteria for meta-analysis comprised randomized controlled trials (RCTs) comparing the use of combination laser therapy with/without adjunctive mechanical for the non-surgical management of periodontitis. From 57 initial articles, 6 full-text articles were assessed for eligibility. Two studies were excluded, one study was not a randomized clinical trial (case series), and one study was an in vitro study. Four RCTs were included in the meta-analysis. It was shown that combination of Nd:YAG and Er:YAG may be beneficial for non-surgical periodontal therapy with an additional average reduction in pocket depth and clinical attachment level reported at 1.01 and 0.77 mm respectively when compared to controls. The findings suggest that the combination of Nd:YAG and Er:YAG lasers may lead to additional clinical improvements compared to nonsurgical treatment alone. Future research is needed to substantiate these findings and optimize clinical guidelines including more specific laser protocols. Preliminary data suggest favorable outcomes following the combination of Nd:YAG and Er:YAG lasers for non-surgical periodontal therapy.

Alveolar bone defects caused by tooth loss often lead to challenges in implant dentistry, with a need for development of optimal bone biomaterials to predictably rebuild these tissues. To address this problem, we fabricated a novel bone block using platelet-rich fibrin (PRF) and Deproteinized Bovine Bone Mineral (DBBM), and characterized their mechanical and biological properties. The bone block was prepared by mixing DBBM, Liquid-PRF, and Solid-PRF fragments in various combinations as follows: (1) BLOCK-1 made with Solid-PRF fragments + DBBM, (2) BLOCK-2 made with Liquid-PRF + DBBM, (3) BLOCK-3 made with Solid-PRF fragments + Liquid-PRF + DBBM. The time for solidification and the degradation properties were subsequently recorded. Scanning electron microscopy (SEM) and tensile tests were carried out to investigate the microstructure and mechanical properties of each block. The bioactivity of the three groups towards osteoblast differentiation was also evaluated by culturing cells with the conditioned medium from each of the three groups including cell proliferation assay, cell migration assay, alkaline phosphatase (ALP) staining, and alizarin red staining (ARS), as well as by real-time PCR for genes encoding runt-related transcription factor 2 (RUNX2), ALP, collagen type I alpha1(COL1A) and osteocalcin (OCN). BLOCK-3 made with Solid-PRF fragments + Liquid-PRF + DBBM had by far the fastest solidification period (over a 10-fold increase) as well as the most resistance to degradation. SEM and tensile tests also revealed that the mechanical properties of BLOCK-3 were superior in strength when compared to all other groups and further induced the highest osteoblast migration and osteogenic differentiation confirmed by ALP, ARS and real-time PCR. PRF bone blocks made through the combination of Solid-PRF fragments + Liquid-PRF + DBBM had the greatest mechanical and biological properties when compared to either used alone. Future clinical studies are warranted to further support the clinical application of PRF bone blocks in bone regeneration procedures.

BACKGROUND While suggested to be effective in tissue regeneration, the effects of horizontal platelet-rich fibrin (H-PRF) bone block in sinus augmentation have not been verified in an animal model. METHODS Twelve male New Zealand white rabbits that underwent sinus augmentation were divided into two groups: deproteinized bovine bone mineral (DBBM) only and H-PRF bone block. H-PRF was prepared at 700 × g for 8 min using a horizontal centrifuge. The H-PRF bone block was prepared by mixing 0.1 g DBBM with H-PRF fragments and then adding liquid H-PRF. Samples were collected after 4 and 8 weeks and analyzed using microcomputed tomography (micro-CT) for vertical bone gain of the sinus, bone volume/total volume (BV/TV) percentage, trabecular number (Tb.N), trabecular thickness (Tb.Th), and trabecular separation (Tb.Sp). Then, histological analyses were performed to investigate new blood vessels, material residue, bone formation and osteoclasts. RESULTS Higher vertical bone gain of the sinus floor, BV/TV percentage, Tb.Th, and Tb.N and lower Tb.Sp were found in the H-PRF bone block group at both time points compared with the DBBM group. Higher amounts of new blood vessels and more osteoclasts were found in the H-PRF bone block group than in the DBBM group at both time points, especially in the regions close to the bone plate. More new bone formation and less material residue were observed in the H-PRF bone block group at 8 weeks. CONCLUSIONS H-PRF bone block showed greater potential for sinus augmentation by promoting angiogenesis, bone formation and bone remodeling in a rabbit model.

Implants are widely used in medical applications and yet macrophage-mediated foreign body reactions caused by implants severely impact their therapeutic effects. Although the extensive use of multiple surface modifications has been introduced to provide some mitigation of fibrosis, little is known about how macrophages recognize the stiffness of the implant and thus influence cell behaviors. Here, we demonstrated that macrophage stiffness sensing leads to differential inflammatory activation, resulting in different degrees of fibrosis. The potential mechanism for macrophage stiffness sensing in the early adhesion stages tends to involve cell membrane deformations on substrates with different stiffnesses. Combining theory and experiments, we show that macrophages exert traction stress on the substrate through adhesion and altered membrane curvature, leading to the uneven distribution of the curvature-sensing protein Baiap2, resulting in cytoskeleton remodeling and inflammation inhibition. This study introduces a physical model feedback mechanism for early cellular stiffness sensing based on cell membrane deformation, offering perspectives for future material design and targeted therapies.

Dental implant failure cannot always be explained by clinical risk factors. Recent literature suggests that immune cells are pivotal players in the integration of biomaterials and have a co-relationship within a set of osteal macrophages known as "OsteoMacs." These cells have been known to polarize quickly between a M1 pro-inflammatory and a M2 wound healing state during implant osseointegration. OsteoMacs play a critical immune surveillance role in the osseointegration of dental implant healing and bone homeostasis. This review is intended to provide an overview of the current understanding of OsteoMacs and their role in early implant failure and osseointegration.

Objectives Platelet-rich fibrin (PRF) has been utilized in regenerative medicine as a concentration of autologous platelets and growth factors that stimulates tissue regeneration. More recently, liquid-PRF (also called injectable-PRF; i-PRF) has been brought to market utilizing PET plastic tubes. Due to new advances made in tube technology, the first aim of the present study was to investigate the liquid consistency of liquid-PRF utilizing both standard and chemically modified PET plastic tubes. Furthermore, it is well known that the conversion of PRF into a fibrin matrix is derived from the temperature-controlled enzymatic process that converts liquid fibrinogen and thrombin to solid fibrin. This study also investigated for the first time the use of a cooling device (Bio-Cool) to extend the liquid working properties of liquid-PRF. Materials and methods In total, 30 participants enrolled in this study. From each patient, four tubes of liquid-PRF were drawn, two standard white Vacuette tubes and two blue chemically modified hydrophobic tubes. Following centrifugation at 700 RCF-max for 8 min in a Bio-PRF horizontal centrifuge, one white and one blue tube were kept upright at room temperature, while the other white and blue tube were placed within the cooling device. Thereafter, the liquid-PRF layers were monitored over time until clotting occurred. Patient gender, age, and altitude above sea level (+ 5000 ft) were recorded and compared for clotting times. Results The findings from the present study demonstrated that the chemically modified PET tubes performed 37% better than the control tubes (extended the working properties of liquid-PRF by over 20 min). Most surprisingly, tubes kept in the cooling device demonstrated an average of 90 min greater working time (270% improvement). While patients living at altitude did significantly improve the clotting ability of liquid-PRF, no differences were observed when comparing male vs female or younger vs older patients in liquid-PRF clotting times. Conclusions Cooling of blood following centrifugation represented a 270% improvement in working properties of liquid-PRF. Optimization of liquid-PRF tubes utilizing chemically modified hydrophobic PET tubes also delayed the clotting process by 37%. Patient gender and age had little relevance on liquid-PRF. Clinical relevance The present findings demonstrate for the first time that cooling of liquid-PRF is able to extend the working properties of liquid-PRF by over 90 min. Thus for clinicians performing longer clinical procedures, the cooling of blood may represent a viable strategy to improve the working time of liquid-PRF in clinical practice.

Most available antiseptic solutions have strong antibacterial effects, but many also possess major cytotoxic effects on gingival fibroblasts, osteoblasts, osteoprogenitor cells, and/or epithelial cells. A novel VEGA Oral Care Recovery Kit (StellaLife) consisting of 16 active ingredients that are monographed in the Homeopathic Pharmacopeia of the United States (HPUS) has gained tremendous momentum as a replacement for more cytotoxic oral rinses such as chlorhexidine. While accumulating evidence has thus far supported its use, little of the gathered data have fully described the properties of the oral formulation. Therefore, the aim of the present review article was 3-fold. First, a biological characterization regarding the active ingredients found in StellaLife Recovery Kit including their biological properties was assessed in 4 predominant categories; 1) antimicrobial resistance, 2) accelerated wound healing, 3) pain management control, and 4) anti-cancer properties. The second aim of this review article was to assess both fundamental and clinical research to date comparing VEGA oral rinse (StellaLife) to the more commonly utilized CHX for differences regarding their effect on decreasing bacterial loads as well as cell viability, survival, proliferation, and expression of both regenerative cytokines and inflammatory markers. Lastly, clinical case examples are presented describing the use of StellaLife remedies in a variety of clinical situations. These include but are not limited to wisdom-tooth extraction, extraction site management, dental implants and ridge augmentation, soft-tissue grafting procedures, frenectomies, and also temporary relief of dry sockets, dry mouth, aphthous ulcers, mucositis, lichen planus, among others. In summary, findings from the present review article provide evidence from basic laboratory experiments that validate clinical studies supporting the use of the StellaLife oral rinse regarding its superior biocompatibility and wound healing properties when compared to common antiseptic solutions such as CHX.

Objectives The aim of this study was to evaluate the in vitro effect of enamel matrix derivative (EMD) and hyaluronic acid (HA) and their synergistic combination on lipopolysaccharides (LPS)-induced inflammation in human keratinocytes and osteoblasts. Material and methods Cells were challenged with LPS (1 μg/ml) and cultured in the following treatment groups with EMD (30 mg/ml) and HA (30 mg/ml): LPS, EMD, HA, EMD + HA, EMD + LPS, HA + LPS, and EMD + HA + LPS. Cell viability, inflammatory cytokine expression, and cell migration were determined using colorimetric assay, quantitative real-time polymerase chain reaction (qPCR), and scratch wound healing assay, respectively. Results Cell viability was decreased when exposed to LPS compared to the controls. Overall, LPS treatment expressed upregulation on inflammatory cytokine tumor necrosis factor alpha (TNF-α), interleukin 1 beta (IL-1β), and interleukin 6 (IL-6). EMD and HA reduced up to 3.0-fold the cytokine expression caused by LPS (p Conclusions EMD and HA are advantageous biomaterials that individually generate strong directional migratory keratinocyte and osteoblast response. Their combination also enhances cell viability, and anti-inflammatory and migratory abilities to promote healing specially under LPS inflammatory stimulus. Future in vivo and animal research is necessary to further characterize the effect of EMD and HA on periodontal regeneration. Clinical relevance The use of EMD in conjunction with HA resulted in a reduction of inflammation and improvement of tissue healing at wound sites. Both biomaterials combined may potentially improve the effectiveness of bone regeneration in periodontal bone defects, pointing to the potential clinical relevance of both materials in regenerative periodontal surgery.

Objective To investigate the efficacy of platelet-rich fibrin (PRF) for the socket healing after removal of mandibular third molars when compared to natural wound healing. Methods This systematic review and meta-analysis were conducted according to PRISMA guidelines. The eligibility criteria comprised randomized controlled trials (RCTs) comparing the clinical outcomes of PRF with that of natural healing. Outcomes measured include post-operative pain, analgesics taken, swelling, soft tissue healing, bone healing, complication rates, as well as incidence of alveolar osteitis (AO, dry socket). Results From 194 articles identified, 18 RCTs were included. Overall, 15 of 18 RCTs demonstrated significantly better outcomes in terms of reduced complication rates, healing rates, or patient reported pain scores in the PRF group when compared to control. Data from all studies demonstrated that PRF was able to significantly lower the rate of AO from 15.9 % in the control group to 5.8 % in the PRF group, representing a ∼3-fold reduction. All studied investigating soft tissue healing with PRF demonstrated better outcomes in favor of PRF group. Conclusions PRF was shown to decrease post-op pain/morbidity, have favored soft tissue healing, and possess lower complication rates or AO incidence. PRF therefore proves to be a viable treatment adjunct following removal of mandibular third molars.

The aim of the present systematic review with meta-analysis was to investigate the clinical effectiveness of EMD (enamel matrix derivative) using a minimally invasive surgical technique (MIST) or flapless approach for the treatment of severe periodontal probing depths.A systematic review of the literature including searches in PubMed/Medline, Cochrane Library, Google Scholar, and Grey Literature databases as well as manual searches was performed on September 1st, 2021. Studies utilising EMD in a non-surgical or minimally invasive approach were included. The eligibility criteria comprised randomised controlled trials (RCTs) comparing minimally-invasive/flapless approaches with/without EMD for the treatment of probing depths5 mm.From 1525 initial articles, 7 RCTs were included and 12 case series discussed. Three studies investigated a MIST approach, whereas 3 studies utilised a flapless approach. One study compared EMD with either a MIST or a flapless approach. The RCTs included ranged from 19-49 patients with at least 6 months of follow-up. While 5 of the studies included smokers, patients smoking20 cigarettes/day were excluded from the study. The meta-analysis revealed that EMD with MIST improved recession coverage (REC) and bone fill (BF) when compared to MIST without EMD. However, no difference in CAL or PD was observed between MIST + EMD vs MIST without EMD. No statistically significant advantage was found for employing the EMD via the flapless approach.Implementing EMD in MIST procedures displayed statistically significant improvement in REC and BF when compared to MIST alone. These findings suggest that MIST in combination with EMD led to improved clinical outcomes while EMD employed in nonsurgical flapless therapy yielded no clinical benefits when compared to nonsurgical therapy alone without EMD. More research is needed to substantiate these findings.

Tissue regenerative procedures aim to enhance regeneration of altered tissue. Extensive research has been carried out in this area and all proposed procedures present limitations. In this context the area of platelet-rich fibrin (PRF) research has gained tremendous awareness in the latest years. PRF is a low-cost regenerative modality that facilitates soft tissue regeneration derived from 100% autologous sources. It forms a fibrin mesh that liberates growth factors in a slow and prolonged manner and also contains supra-physiological concentrations of leukocytes. Reports from the literature have suggested that these leukocyte-rich blood-preparations are capable of improving wound healing, diminishing post-operative pain, and additionally minimizing the risk of infection. In our article we present the first clinical case where PRF was used as a wound healing accelerator of gingival lesions in a chemical soft tissue burn after teeth whitening.

Platelet-rich fibrin (PRF) has been widely applied in regenerative therapy owing to its simple preparation protocol. To date, the original protocol for preparing leukocyte-rich (L)-PRF has been modified to produce derivatives such as advanced (A)-PRF, concentrated growth factors (CGF), and horizontal (H)-PRF. However, these derivatives have not been rigorously compared to explore possible differences. We previously developed and validated a nondestructive near-infrared (NIR) imaging method to quantitatively examine the platelet distribution in PRF matrices. To further evaluate the characteristics of platelets in PRF, we herein examined the distribution of activated platelets. Four types of PRF matrices were prepared under different centrifugal conditions from blood samples obtained from the same healthy donors. After fixation and compression, the matrices were stained immunohistochemically without sectioning and visualized using an NIR imager. Qualitative morphological analysis revealed that whole platelets were distributed widely and homogeneously in H-PRF and A-PRF, but localized along the distal tube surface in L-PRF and CGF. Activated platelets were distributed as were whole platelets in A-PRF, L-PRF, and CGF, but localized mainly in the "buffy coat" region in H-PRF. Quantitative analysis revealed that there was no significant difference in the ratio of activated to whole platelets between PRF derivatives. These findings suggest that platelet activation is similarly induced in fibrin matrices regardless of centrifugal speed or rotor angulation. However, only the H-PRF group was distinguishable from the other PRF derivatives in terms of activated platelet distribution.

Platelet-rich fibrin (PRF) is prepared from whole blood without any exogenous coagulation factors. Several preparation methods have now been introduced, particularly with differences in centrifugation parameters including g-force and time to improve their regenerative potential. Nevertheless, the centrifugation systems have not yet been clearly investigated for their influences on the PRF clot properties. The aim of the present study was to visually and histologically characterize the cell separation manner and blood cell localization on the whole PRF clots prepared by two different centrifugation system, fixed-angle and horizontal centrifugation. Leukocyte- and platelet-rich fibrin (L-PRF) was prepared on a fixed-angle centrifuge machine (IntraSpin, Intra-Lock, FL, USA) at 2700 rpm (~400 g at the RCF-clot; ~700 g at the RCF-max) for 12 min. The PRF prepared by horizontal centrifugation was prepared on a horizontal centrifugation (H-PRF) (Eppendorf 5702, Eppendorf, Germany) at 700 g at the RCF-max for 8 min. The cell morphology and localization were observed on the surface of PRF clots by scanning electron microscopy (SEM) and histologically by transaxial frozen sections by means of a film method. L-PRF clots demonstrated a sloped separation between the upper plasma and the bottom red blood cell (RBC) layers according to the angle of the rotor. Red dots were often observed on the distal walls of the tubes in the upper layers, consisting of aggregations of RBCs, leukocytes and platelets by SEM and histology. Clots produced on the horizontal centrifuge showed much smoother cell layer distribution/separation along the tube surfaces when compared to L-PRF. Horizontal centrifugation also demonstrated more evenly distributed platelets throughout the PRF clots when compared to L-PRF that gathered the majority of cells along the distal tube surface or within the buffy-coat region. In summary, it was found that horizontal centrifugation resulted in a more uniform blood cell separation of PRF clots when compared to the accumulation of cells gathered along the distal tube surfaces produced prepared by fixed-angle centrifugation. Future research is needed to evaluate the benefit of horizontal centrifugation in clinical practice.

OBJECTIVES Platelet-rich fibrin (PRF) in liquid form has shown advantages in tissue engineering including acting as injectable fillers and drug carriers. However, few studies have investigated the best relative centrifugal force (RCF) for preparing liquid PRF. The aim of the present study was to find out optimal centrifugation force for preparing liquid PRF. MATERIALS AND METHODS Liquid PRF was prepared using horizontal centrifugation (liquid H-PRF) with RCF ranging from 100 g, 300 g, 500 g, to 700 g for 8 min. The volume, weight, solidification time, and tensile properties were subsequently investigated. Scanning electron microscopy (SEM) and rheologic tests were carried out to investigate the microstructure and rheologic properties of liquid H-PRF after natural polymerization. The total number, concentration, and distribution of cells within each liquid H-PRF was evaluated by complete blood count (CBC) analysis and hematoxylin-eosin staining. RESULTS As RCF values increased, the volume and weight of liquid H-PRF both increased accordingly. SEM images revealed that as the centrifugal force increased, the fibrin bundles became thinner with a denser fibrin network, and rheologic tests revealed improved mechanical properties. CBC analysis demonstrated that 500 g group had the highest number of leukocytes and neutrophils, whereas 100 g group yielded the highest concentration of leukocytes and platelets. Furthermore, histological analysis suggests that cells obtained by 500 g for 8 min were most evenly distributed in liquid H-PRF. CONCLUSIONS In summary, the present study provided insights into the contents of liquid H-PRF prepared at different centrifugation forces, enabling clinicians to choose proper centrifugation forces based on their needs. CLINICAL RELEVANCE The present findings provide theoretical basis for clinical choice of liquid H-PRF protocol from mechanical, cell contents, and histological aspects.

Sepsis is a dysregulation of the immune response to pathogens and has high morbidity and mortality worldwide. However, the unclear mapping and course of dysregulated immune cells currently hinders the development of advanced therapeutic strategies to treat sepsis. Here, evidence is provided using single-cell RNA sequencing from peripheral blood mononuclear cells in sepsis that pathogens attacking monocytes/macrophages disrupt their immune function. The results reveal an enormous decline in monocytes/macrophages in sepsis and chart the evolution of their impaired phagocytosis (Pha) capabilities. Inspired by these findings, nanoparticles, named "Alpha-MOFs," are developed that target dysfunctional monocytes/macrophages to actively (A) lift (L) Pha by the release of lysosome-sensitive ions from a mineralized metal-organic framework (MOF). Alpha-MOFs have good stability and biosafety in peripheral blood and efficiently targeted monocytes/macrophages. They also release calcium and zinc ions into monocyte/macrophage lysosomes to promote the Pha and degradation of bacteria. Taken together, these results suggest that Alpha-MOFs rescue monocytes/macrophages dysfunction and effectively improve their survival rate during sepsis.

This study presents the Segmented Colour Feature Extreme Learning Machine (SCF-ELM). The SCF-ELM is inspired by the Extreme Learning Machine (ELM) which is known for its rapid training and inference times. The ELM is therefore an ideal candidate for an ensemble learning algorithm. The Colour Feature Extreme Learning Machine (CF-ELM) is used in this study due to its additional ability to extract colour image features. The SCF-ELM is an ensemble learner that utilizes feature mapping via k-means clustering, a decision matrix and majority voting. It has been evaluated on a range of challenging agricultural object classification scenarios including weed, livestock and machinery detection. SCF-ELM model performance results were excellent both in terms of detection, 90 to 99% accuracy, and also inference times, around 0.01(s) per image. The SCF-ELM was able to compete or improve upon established algorithms in its class, indicating its potential for remote computing applications in agriculture.

Platelet-rich fibrin (PRF) has been utilized as a substitute for resorbable membranes during guided bone regeneration therapy as it is a more bioactive biomaterial with living cells and growth factors than resorbable membranes. Nevertheless, PRF poses obvious disadvantages in its mechanical strength since its rapid degradability has been shown to typically resorb within a 2-week time period. In the present study, the barrier function and biological and mechanical properties of PRF were investigated both as standard therapy and after thermal processing. Two heating processes were applied: both single-side heating and double-side heating at 90��C for 10���s using a metal plate heater. The appearance and weight of PRF membranes were documented after heating, along with their morphological and mechanical properties evaluated by scanning electron microscope and tensile strength tests. The viability of cells found within PRF membranes was also evaluated using live/dead cell viability and CCK-8 (cell counting kit-8) assays. To comprehensively evaluate the barrier function of PRF membranes, Hoechst staining of human gingival fibroblasts, which can be distinguished from cells within the PRF membrane by emitting blue light at an excitation wavelength of 488���nm, was seeded onto the surface of PRF membranes. Furthermore, osteoblasts were cultured with extracts from different PRF groups to evaluate the biocompatibility of PRF membranes. The degradation rate of PRF membranes was examined by digestion assay. Compared with the nonheated PRF control, the size and weight of PRF membranes led to a significant decrease with a denser PRF microstructure following heating. In summary, the double-sided heating of PRF membranes not only demonstrated an improvement in mechanical and degradation properties but also led to a decrease in cell viability and proliferation.

To histologically compare the effects of platelet-rich fibrin (PRF) produced using different protocols on periodontal wound healing/regeneration in periodontal defects in dogs.Dehiscence-type gingival recession and two-wall intrabony defects were created bilaterally in the maxillary canines and mandibular premolars, respectively, in four beagle dogs. The recession defects were randomly treated with coronally advanced flap (CAF) alone, CAF and PRF produced via fixed-angle centrifugation (F-PRF; Leukocyte and PRF (L-PRF) protocol) or CAF and PRF produced via horizontal centrifugation (H-PRF). After 2 weeks, the two-wall intrabony defects were randomly treated as follows: open flap debridement (OFD), OFD + F-PRF, OFD + H-PRF and OFD + heated albumin with PRF using bio-heat technologies (Alb-PRF). Eight weeks after the 2nd reconstructive surgery, the animals were euthanised for histological evaluation.In the PRF-applied defects, new bone and new cementum formation occurred to varying degrees regardless of the protocols used to produce PRF. Particularly in the two-wall intrabony defects, new bone formation extended from the host bone toward the coronal region of the defects in the H-PRF applied sites compared with those in the OFD, F-PRF and Alb-PRF groups, and the H-PRF group showed the greatest amount of newly formed cementum.PRF induced periodontal regeneration in gingival recession and two-wall intrabony defects in dogs. Further studies are needed to determine the optimal protocol for obtaining predictable periodontal regeneration in periodontal defects in humans.

Chronic inflammation is a pathological process where cells of the mesenchymal lineage become a major source of inflammatory mediators. Platelet-rich fibrin (PRF) has been shown to possess potent anti-inflammatory activity in macrophages, but its impact on mesenchymal cells has not been investigated. The aim of this study was, therefore, to expose mesenchymal cells to inflammatory cytokines together with lysates generated from liquid platelet-poor plasma (PPP), the cell-rich buffy coat layer (BC, concentrated-PRF or C-PRF), and the remaining red clot layer (RC), following centrifugation of blood. Heating PPP generates an albumin gel (Alb-gel) that when mixed back with C-PRF produces Alb-PRF. Membranes prepared from solid PRF were also subjected to lysis. We report here that lysates of PPP, BC, and PRF decreased the cytokine-induced expression of interleukin 6 (IL6) and nitric oxide synthase (iNOS) in the bone marrow-derived ST2 cells. Consistently, PPP, BC, and PRF greatly decreased the phosphorylation and nuclear translocation of p65 in ST2 cells. The inflammatory response caused by Pam3CSK4 was reduced accordingly. Moreover, PPP, BC, and PRF reduced the enhanced expression of inflammatory mediators IL6 and iNOS in 3T3-L1 pre-adipocyte mesenchymal cells, and iNOS and CCL5 in murine calvarial cells. Surprisingly, PRF lysates were not effective in reducing the inflammatory response of human gingival fibroblasts and HSC2 epithelial cells. The data from the present study suggest that both liquid PRF and solid PRF exert potent anti-inflammatory activity in murine mesenchymal cells.

Accumulating evidence has shown that vitamin D deficiency has been linked with an up to 300% increase in early implant failure. The aim of this study was to investigate a comprehensive pre-surgical dental support program (DentaMedica) on its ability to increase vitamin D and antioxidant levels prior to implant surgery.Twenty patients were enrolled in this study. To quantify vitamin D levels, two in-office vitamin D finger-prick tests (10-15 min in length) were compared to levels obtained from a standard laboratory blood test. An antioxidant testing device was also utilised to investigate the impact of this pre-surgical supplementation program on antioxidant scores 0 and 6 weeks post supplementation.It was first found that 65% of the population had an initial vitamin D deficiency (below 30 ug/ml). After supplementation, vitamin D levels increased from an average of 24.76 ng/ml to 50.11 ng/ml (ranging from 38 to 85.50 ng/ml). No statsitcally significant differences were observed between any of the 3 testing devices (2 in-office finger-prick tests and a standard blood sample). Initial antioxidant levels registered on the biophotonic unit averaged an antioxidant score of 27250 ± 10992.22. Following supplementation, an increase of 54% from baseline values (41950 ± 9276.31) was reported.The results from this study show convincingly that the majority of the tested population was vitamin D deficient. It was further found that both in-office finger-prick devices demonstrated results comparable to standard lab scores (usually within an average 2-3 ng/ml). Following supplementation, all patients reached sufficient levels following this 4-6 week pre-surgical supplementation program specific to implant dentistry.

Platelet-rich fibrin (PRF) has been utilized in regenerative medicine as a concentration of autologous platelets and growth factors that stimulates tissue regeneration. More recently, liquid-PRF (also called injectable-PRF; i-PRF) has been brought to market utilizing PET plastic tubes. Due to new advances made in tube technology, the first aim of the present study was to investigate the liquid consistency of liquid-PRF utilizing both standard and chemically modified PET plastic tubes. Furthermore, it is well known that the conversion of PRF into a fibrin matrix is derived from the temperature-controlled enzymatic process that converts liquid fibrinogen and thrombin to solid fibrin. This study also investigated for the first time the use of a cooling device (Bio-Cool) to extend the liquid working properties of liquid-PRF.In total, 30 participants enrolled in this study. From each patient, four tubes of liquid-PRF were drawn, two standard white Vacuette tubes and two blue chemically modified hydrophobic tubes. Following centrifugation at 700 RCF-max for 8 min in a Bio-PRF horizontal centrifuge, one white and one blue tube were kept upright at room temperature, while the other white and blue tube were placed within the cooling device. Thereafter, the liquid-PRF layers were monitored over time until clotting occurred. Patient gender, age, and altitude above sea level (+ 5000 ft) were recorded and compared for clotting times.The findings from the present study demonstrated that the chemically modified PET tubes performed 37% better than the control tubes (extended the working properties of liquid-PRF by over 20 min). Most surprisingly, tubes kept in the cooling device demonstrated an average of 90 min greater working time (270% improvement). While patients living at altitude did significantly improve the clotting ability of liquid-PRF, no differences were observed when comparing male vs female or younger vs older patients in liquid-PRF clotting times.Cooling of blood following centrifugation represented a 270% improvement in working properties of liquid-PRF. Optimization of liquid-PRF tubes utilizing chemically modified hydrophobic PET tubes also delayed the clotting process by 37%. Patient gender and age had little relevance on liquid-PRF.The present findings demonstrate for the first time that cooling of liquid-PRF is able to extend the working properties of liquid-PRF by over 90 min. Thus for clinicians performing longer clinical procedures, the cooling of blood may represent a viable strategy to improve the working time of liquid-PRF in clinical practice.

Medication related osteonecrosis of the jaw (MRONJ) is characterized by exposed necrotic bone in the maxillofacial region that persists for more than eight weeks in patients taking antiresorptive or antiangiogenic drugs for bone metastasis or osteoporosis. The management of such condition depends on several factors, among which the staging of MRONJ. Though, a specific gold standard treatment has not been established to date. The aim of this case series is to describe the outcome of surgical treatment of MRONJ with the adjunct of Platelet-rich Fibrin (PRF). Eleven patients under therapy with alendronate underwent surgical removal of necrotic bone and debridement, followed by placement of PRF membranes in the bone defect. The outcome of the surgical treatment was successful in all patients, in a follow-up range from 12 to 36 months. In the cases presented, the macroscopic evaluation showed excellent and fast soft tissue healing, with no recurrence of bone exposure and no signs of infections. PRF membranes were also effective for postsurgical pain control. The use of PRF may represent a valuable adjunct in the surgical management of MRONJ.

The purpose of this systematic review was to investigate the efficacy of antibiotic prophylaxis (AP) in intraoral bone grafting procedures for the prevention of postoperative infection (POI). Electronic and manual searches were conducted to identify randomized controlled trials (RCTs). The primary outcome assessed was receptor site POI; secondary outcomes assessed included donor site POI, wound dehiscence, pain, graft failure, need for re-grafting, adverse events, patient satisfaction, and quality of life. A random-effects meta-analysis was conducted to obtain risk ratios of dichotomous data. Four RCTs were selected: one examined AP versus placebo and concluded that there was an increased risk of POI without AP; three examined comparative antibiotic regimens and found no statistically significant difference between them. A meta-analysis of prophylactic regimens, including data from the two RCTs that compared preoperative AP to perioperative AP, indicated no statistically significant difference in POI outcomes (P= 0.94, risk ratio 0.94). It was not possible to conduct further meta-analyses for POIs or for any secondary outcomes due to insufficient published data. The risk of bias assessment indicated an overall unclear risk of bias. On the basis of the present review, there is insufficient evidence to support or refute AP for the prevention of POIs in intraoral bone graft placement procedures.

Platelet-rich fibrin (PRF) has been proposed as an autologous membrane with the advantages of host accumulation of platelets and leukocytes with entrapment of growth factors. However, limitations include its faster resorption properties (~2 weeks). Interestingly, recent studies have demonstrated that by heating a liquid platelet-poor plasma (PPP) layer, the resorption properties of heated albumin (albumin gel) can be extended from 2 weeks to greater than 4 months (e-PRF). The aim of the present study was to characterize the biological properties of this novel regenerative modality. Whole blood collected from peripheral blood in 9-mL plastic tubes was centrifuged at 700

BACKGROUND The history of allogenic tooth transplantation can be traced back to the 16th century. Although there have been many successful cases, much needs to be better understood and researched prior to the technique being translated to everyday clinical practice. CASE SUMMARY In the present report, we describe a case of allogenic tooth transplantation between a mother and her daughter. The first left maxillary molar of the mother was diagnosed with residual root resorption and needed to be extracted. The 3rd molar of the daughter was used as a donor tooth. Prior to transplantation, a 3D printing system was introduced to fabricate an individualized reamer drill specifically designed utilizing the donor’s tooth as a template. The specific design of our 3D printed bur allowed for the recipient site to better match the donor tooth. With the ability to 3D print in layers, even the protuberance of the root can be matched and 3D printed, thereby minimizing unnecessary bone loss. CONCLUSION Our study is a pioneering case combining 3D printing with allogenic tooth transplantation, which could be able to minimize unnecessary bone loss and improve the implant stability. This article aims to enhance our understanding of allogenic tooth transplantation and 3D printing, and may potentially lead to tooth transplantation being utilized more frequently - especially since transplantations are so commonly utilized in many other fields of medicine with high success rates.

Immune response to implantation materials plays a critical role during early local inflammation and biomaterial-induced regeneration or restoration. A novel platelet concentrate termed i-PRF (injectable platelet-rich fibrin) has recently been developed without any additives by low centrifugation speeds. To date, scientists have investigated the capability of releasing growth factors to improve regeneration but have ignored whether i-PRF can inhibit the inflammatory effect around the wound. The present study investigated the anti-inflammation effects of i-PRF on immune response-related cells, especially macrophages and dendric cells. We found that i-PRF reduced pro-inflammatory M1 phenotype of macrophages and activated dendritic cells around muscle defect that was injected with bacterial suspension. Moreover, in vitro experiments showed similar results. i-PRF deleted inflammatory response caused by lipopolysaccharide to some extent. We determined that TLR4, an activator of inflammatory stimulation and p-p65, a key factor belongs to classical inflammatory related NF-κB signal pathway, can be inhibited by use of i-PRF. Results indicate the potential anti-inflammatory role of i-PRF during regeneration and restoration.