Platelet-rich Fibrin Scaffold Research Articles

Two-Dimensional Radiographs and Cone-beam Computed Tomography Assessment of Concentrated Growth Factor and Platelet-Rich Fibrin Scaffolds in Regenerative Endodontic Treatment of Immature Incisors with Periapical Radiolucency: A Randomized Clinical Trial

IntroductionThe primary aim of this study was to compare the radiographic changes of immature incisors with periapical radiolucency after treatment with platelet-rich fibrin (PRF) and concentrated growth factor (CGF) platelet concentrate scaffolds as well as assessment of the clinical success rate over 12 months. The secondary aim was to monitor the radiographic changes in terms of reduction of periapical lesion diameter (PALD), root dentine thickness (RDT), root length (RL), and apical foramen width (AFW). The tertiary aim was to assess and pulp responses, after 12 months. MethodsFifty six children with seventy necrotic, single-rooted maxillary incisors with periapical radiolucency were treated with either CGF or PRF scaffolds (35 teeth per group). Two patients with 4 teeth (2 teeth in each group) failed to attain the follow-up recalls. Radiographic changes in terms of reduction of PALD, RDT, RL, and AFW were monitored using a 2-dimensional (2D) radiograph and cone-beam computed tomography (CBCT) scan. The clinical performance of teeth receiving both scaffolds was assessed after 6 and 12 months. Categorical and continuous data were analyzed using the chi-square test and the t test, respectively. The time and group effects on the means of different radiographic dimensions were tested using the general linear model. Bland-Altman plots were used to assess the level of agreement between the 2D radiographs and CBCT. The level of significance was defined at 0.05 and a 95% confidence interval. ResultsThe means of PALD and RL showed significant enhancement in the CGF group compared to the PRF group (P < .05). While the difference between the 2 scaffolds in terms of RDT and AFW was not significant (P > .05). The findings of the 2D radiograph and CBCT were consistent. Clinically, both scaffold success rates were similar (93.9%) over the follow-up intervals. The influence of study independent variables had no significant effect on the success of the regenerative endodontic procedures outcome (P > .05). There was no significant difference in the positive pulp responses to the thermal and electric pulp tests after one year of treatment (P > .05). ConclusionsAccording to the short-term follow-up, PRF and CGF were successful in treating immature teeth with periapical radiolucency by regenerative endodontics. Both scaffold systems induced periapical healing and root lengthening with significant superiority of CGF.

Improving properties of platelet-rich fibrin scaffold with tannic acid for wound healing.

Platelet-rich fibrin (PRF), which is the rich source of growth factors, has been used as an efficient scaffold in tissue engineering and wound healing. In this study, tannic acid as a green cross-linker with different concentrations (0.5%, 1%, 5% and 10%) was used to improve the properties of PRF. The cross-linked gel scaffolds were evaluated by analyses such as scanning electron microscopy, Fourier transform infrared spectroscopy, swelling and degradation, mechanical strength, cell toxicity, cell adhesion and antibacterial test. The results showed that the scaffold structure changes by increasing cross-linker concentration. The swelling rate decreased from 49% to 5% for the samples without the cross-linker and with tannic acid (10%), respectively. The degradation percentage for the cross-linked samples was 8%, which showed a lower degradation rate than the non-cross-linked samples (63%). The mechanical strength of the scaffold with the cross-linker increased up to three times (Young's modulus for the non-cross linked and the cross-linked samples: 0.01 and 0.6 MPa, respectively). Cytotoxicity was not observed up to 10% cross-linker concentration. The cells proliferated well on the cross-linked scaffolds and also showed a good antibacterial effect. In general, tannic acid can improve the physical and mechanical properties of PRF without negatively affecting its biological properties.

A comparative clinico-radiographic analysis of regenerative endodontic procedure on immature necrotic permanent teeth using blood clot and PRF as scaffold: A retrospective study

ObjectivesTo evaluate the clinical and radiographic success rate of blood clot and platelet rich fibrin (PRF) as a scaffold system in regenerative endodontic procedure in immature traumatized necrotic teeth.. Materials and methodsThis retrospective study examined the records of 28 subjects with necrotic immature open apex due to trauma treated with blood clot or PRF as a scaffold in regenerative endodontic procedure. The disinfection was carried out with calcium hydroxide as an intra-canal medicament. The clinical outcome was recorded using a binary variable of presence or absence of pain and intra-oral swelling. The radiographic outcome was recorded for periapical healing using Ørstavik’s Periapical Index and apical response using Chen and Chen index. Comparison of frequencies of categories of variables with groups was done using the chi-square test. The pairwise comparison of time intervals was done using Wilcoxon Signed Ranks Test. ResultsIntra-group comparison of pain and intra-oral swelling had highly significant (p = 0.000) results for both groups over a period of 12 months. Inter-group comparison for clinical outcomes was insignificant. For the radiographic outcome, there was a statistically non-significant difference for periapical healing and apical response for both intra-group and inter-group comparisons. ConclusionBoth PRF and blood clot have a favourable outcome for a regenerative endodontic procedure with a disinfectant protocol using calcium hydroxide as intracanal medicament. Considering the cumbersome procedure involved in procuring PRF scaffold, especially in children, inducing bleeding can be considered a recommended method for a regenerative endodontic procedure.

Osteochondral Regeneration Ability of Uncultured Bone Marrow Mononuclear Cells and Platelet-Rich Fibrin Scaffold.

Platelet-rich fibrin (PRF) and bone marrow mononuclear cells are potential scaffolds and cell sources for osteochondral regeneration. The main aim of this paper is to examine the effects of PRF scaffolds and autologous uncultured bone marrow mononuclear cells on osteochondral regeneration in rabbit knees. Three different types of PRF scaffolds were generated from peripheral blood (Ch-PRF and L-PRF) and bone marrow combined with uncultured bone marrow mononuclear cells (BMM-PRF). The histological characteristics of these scaffolds were assessed via hematoxylin-eosin staining, PicroSirius red staining, and immunohistochemical staining. Osteochondral defects with a diameter of 3 mm and depth of 3 mm were created on the trochlear groove of the rabbit's femur. Different PRF scaffolds were then applied to treat the defects. A group of rabbits with induced osteochondral defects that were not treated with any scaffold was used as a control. Osteochondral tissue regeneration was assessed after 2, 4, and 6 weeks by macroscopy (using the Internal Cartilage Repair Society score, X-ray) and microscopy (hematoxylin-eosin stain, safranin O stain, toluidine stain, and Wakitani histological scale, immunohistochemistry), in addition to gene expression analysis of osteochondral markers. Ch-PRF had a heterogeneous fibrin network structure and cellular population; L-PRF and BMM-PRF had a homogeneous structure with a uniform distribution of the fibrin network. Ch-PRF and L-PRF contained a population of CD45-positive leukocytes embedded in the fibrin network, while mononuclear cells in the BMM-PRF scaffold were positive for the pluripotent stem cell-specific antibody Oct-4. In comparison to the untreated group, the rabbits that were given the autologous graft displayed significantly improved healing of the articular cartilage tissue and of the subchondral bone. Regeneration was gradually observed after 2, 4, and 6 weeks of PRF scaffold treatment, which was particularly evident in the BMM-PRF group. The combination of biomaterials with autologous platelet-rich fibrin and uncultured bone marrow mononuclear cells promoted osteochondral regeneration in a rabbit model more than platelet-rich fibrin material alone. Our results indicate that autologous platelet-rich fibrin scaffolds combined with uncultured bone marrow mononuclear cells applied in healing osteochondral lesions may represent a suitable treatment in addition to stem cell and biomaterial therapy.

Platelet-Rich Fibrin–Augmented Gap-Bridging Strategy in Rabbit Anterior Cruciate Ligament Repair

Background: We assessed the efficacy of a novel platelet-rich fibrin (PRF)–augmented repair strategy for promoting biological healing of an anterior cruciate ligament (ACL) midsubstance tear in a rabbit model. The biological gap-bridging effect of a PRF scaffold alone or in combination with rabbit ligamentocytes on primary ACL healing was evaluated both in vitro and in vivo. Hypothesis: A PRF matrix can be implanted as a provisional fibrin-platelet bridging scaffold at an ACL defect to facilitate functional healing. Study Design: Controlled laboratory study. Methods: The biological effects of PRF on primary rabbit ligamentocyte proliferation, tenogenic differentiation, migration, and tendon-specific matrix production were investigated for treatment of cells with PRF-conditioned medium (PRFM). Three-dimensional (3D) lyophilized PRF (LPRF)–cell composite was fabricated by culturing ligamentocytes on an LPRF patch for 14 days. Cell-scaffold interactions were investigated under a scanning electron microscope and through histological analysis. An ACL midsubstance tear model was established in 3 rabbit groups: a ruptured ACL was treated with isolated suture repair in group A, whereas the primary repair was augmented with LPRF and LPRF-cell composite to bridge the gap between ruptured ends of ligaments in groups B and C, respectively. Outcomes—gross appearance, magnetic resonance imaging, and histological analysis—were evaluated in postoperative weeks 8 and 12. Results: PRFM promoted cultured ligamentocyte proliferation, migration, and expression of tenogenic genes (type I and III collagen and tenascin). PRF was noted to upregulate cell tenogenic differentiation in terms of matrix production. In the 3D culture, viable cells formed layers at high density on the LPRF scaffold surface, with notable cell ingrowth and abundant collagenous matrix depositions. Moreover, ACL repair tissue and less articular cartilage damage were observed in knee joints in groups B and C, implying the existence of a chondroprotective phenomenon associated with PRF-augmented treatment. Conclusion: Our PRF-augmented strategy can facilitate the formation of stable repair tissue and thus provide gap-bridging in ACL repair. Clinical Relevance: From the translational viewpoint, effective primary repair of the ACL may enable considerable advancement in therapeutic strategy for ACL injuries, particularly allowing for proprioception retention and thus improved physiological joint kinematics.

Genipin modified lyophilized platelet-rich fibrin scaffold for sustained release of growth factors to promote bone regeneration.

Lyophilized platelet-rich fibrin (L-PRF) was shown to further activate resident platelets in platelet-rich fibrin causing a higher amount of growth factors release. However, it still required further experimental studies to resolve the uncontrolled degradation and burst release problem. In this study, the nature crosslinker genipin is introduced to improve the performance of L-PRF scaffold. We used a series of gradient concentration genipin solutions to react with L-PRF. The crosslinking degree, micro morphology, mean pore size, water absorption and mechanical properties of the crosslinked scaffold were evaluated. In order to study the effect of genipin modification on the release kinetics of growth factors from L-PRF, we detected the release of platelet-derived growth factor, vascular endothelial growth factor and transforming growth factor in vitro by ELISA. To investigate the biodegradability of the crosslinked L-PRF in vivo, the scaffolds were transplanted subcutaneously into backs of rats, and the materials were recovered at 1, 2 and 4 weeks after implantation. The biodegradation, inflammatory reaction and biocompatibility of the scaffolds were examined by histological staining. Finally, the genipin crosslinked/uncrosslinked L- Platelet-rich fibrin scaffolds were implanted with freshly prepared SHED cell sheets into rat critical size calvarial defects and the skull samples were recovered to examine the treatment efficacy of genipin crosslinked L-PRF by histologic and radiographic approaches. Results of this study indicated that genipin can be used to modify L-PRF at room temperature at a very low concentration. Genipin-modified L-PRF shows better biomechanical performance, slower biodegradation, good bioavailable and sustained release of growth factors. The 0.01% w/v and 0.1% w/v genipin crosslinked L-PRF have good porous structure and significantly promote cell proliferation and enhance the expression of key genes in osteogenesis in vitro, and work best in promoting bone regeneration in vivo.

Treatment of Necrotic Anterior and Posterior Teeth with Regenerative Endodontic Procedures Using PRF as a Scaffold: A Retrospective Study

We assessed the impact of regenerative endodontic procedures (REP) using a platelet-rich fibrin (PRF) scaffold on necrotic immature permanent anterior and posterior teeth based on the following parameters: periapical healing, changes in root development, and associations between increases in the radiographic root area (RRA), and degree of root to apical closure. The study included 50 teeth consisting of 57 roots (36 anterior and 21 posterior) treated between 2017 and 2019, with an average follow-up of two years. Complete periapical healing was achieved in 91.2% teeth, and uncertain healing was achieved in 8.8%. RRA increased in 95% of teeth and root lengthening was achieved in 86% teeth (without any mutual effect). Apical closure was significantly associated with tooth location (89% and 30% of the posterior and anterior roots, respectively). Trauma was the most common aetiology of necrotic anterior teeth, whereas caries was the only aetiology of necrotic posterior teeth. REP using PRF scaffold achieved a high success rate for periapical healing and root maturation in both anterior and posterior necrotic immature teeth. The favourable results obtained in posterior teeth may encourage the use of REP for treating necrotic immature permanent posterior teeth.

Using platelet-rich fibrin scaffolds with diced cartilage graft in the treatment of empty nose syndrome.

Empty nose syndrome (ENS) is a rare entity in patients who undergo sinonasal surgery due to over-resection of the turbinate. This syndrome leads to debilitating symptoms that include dry nose, painful nasal breathing, paradoxical nasal obstruction, crusting, and sleep disorder. The goal of surgical treatment is to reestablish the volume of the turbinates to rehabilitate the nasal resistance. Endonasal microplasty with cartilage implants on the lateral wall of the nasal cavity is useful for creating the neoturbinate. Here, we present 2 cases that describe the management of empty nose syndrome by endonasal microplasty using platelet-rich fibrin (PRF) scaffolds embedded with a diced cartilage graft. The integration of the PRF scaffolds with diced cartilage efficiently facilitated the reestablishment of the neoturbinate. This autologous biomaterial is suitable for the treatment of ENS.

Development of Vancomycin Delivery Systems Based on Autologous 3D Platelet-Rich Fibrin Matrices for Bone Tissue Engineering.

Autologous platelet-rich fibrin (PRF) is derived from the blood and its use in the bone tissue engineering has emerged as an effective strategy for novel drug and growth factor delivery systems. Studies have approved that combined therapy with PRF ensures higher biological outcomes, but patients still undergo additional treatment with antibiotic drugs before, during, and even after the implantation of biomaterials with PRF. These systematically used drugs spread throughout the blood and lead not only to positive effects but may also induce adverse side effects on healthy tissues. Vancomycin hydrochloride (VANKA) is used to treat severe Staphylococcal infections but its absorption in the target tissue after oral administration is low; therefore, in this study, we have developed and analyzed two kinds of VANKA carriers—liposomes and microparticles in 3D PRF matrices. The adjustment, characterization, and analysis of VANKA carriers in 3D PRF scaffolds is carried out in terms of encapsulation efficiency, drug release kinetics and antibacterial activity; furthermore, we have studied the micro- and macrostructure of the scaffolds with microtomography.

Prospective cohort study of regenerative potential of non vital immature permanent maxillary central incisors using platelet rich fibrin scaffold

Regenerative endodontic procedures have gained momentum as a treatment modality of young immature permanent teeth. Literature reports reveal that platelet-rich fibrin (PRF) stimulates growth factors and induces regeneration. This study was undertaken to assess the regenerative potential of non-vital immature permanent maxillary central incisors using PRF with a follow-up for 2 yrs. 19 patients in the age group of 9–25 yrs with immature, non-vital permanent maxillary central incisors (n = 23) with/without signs and/or symptoms of periapical pathosis and open apex were included in this study. In the first appointment, access opening, canal disinfection and triple antibiotic paste placement were done. In the subsequent visit, PRF was prepared and placed inside the canal. Access was sealed with Mineral trioxide aggregate plug and composite. The patient was reviewed up to 24 mths. The mean difference was statistically analyzed using Friedman test followed by Dunn post hoc test and adjusted by Bonferroni correction (p < 0.05). As per AAE guidelines, the primary and secondary goals were achieved. A significant (p < 0.001) gradual increase in the root length, thickness of dentinal walls and decrease in apical diameter were observed. Within the limitations of this study, PRF placement was clinically and radiographically effective in inducing regeneration of non-vital immature permanent teeth.

PLATELET RICH FIBRIN SCAFFOLD COMBINED WITH INDUCED BLOOD CLOT IN PULP REVASCULARIZATION OF NECROTIC IMMATURE PERMANENT TEETH WITH CHRONIC PERIAPICAL LESIONS: A CASE SERIES

ABSTRACT Background: Traumatized non-vital permanent teeth with incomplete root formation and divergent apices present particular challenges to clinicians during management with traditional approaches. Objectives: This report described the outcomes of pulp revascularization of three traumatized immature necrotic permanent teeth using platelet-rich fibrin scaffold combined with induced blood clot. Materials and Methods: Three patients (two boys aged 8 and 11 years and one girl aged 13 years) were presented with immature maxillary incisors with necrotic pulps. Access cavities were prepared and the root canals were gently irrigated with 1.5% sodium hypochlorite (20 mL/ 5 min). Calcium hydroxide paste was applied three mm short of the root apex and the canals were temporized with intermediate restorative material. At the following appointment after two weeks, the teeth were treated by revascularization protocol using Platelet rich fibrin scaffold combined with induced blood clot and the three cases were clinically and radiographically followed up to eighteen months. Results: The patients were clinically asymptomatic at all follow-up periods. Cone Beam Computed Tomography (CBCT) images revealed evidence of root maturation and healing of the periapical lesions. Calcific intra-canal deposits were noted at the middle and apical thirds of the root canals. Conclusions: Pulp revascularization procedure using Platelet rich fibrin scaffold showed evidence of root elongation, increased dentin thickness and resolution of the periapical lesions.

Human Umbilical Cord Mesenchymal Stem Cells Over Platelet Rich Fibrin Scaffold for Mandibular Cartilage Defects Regenerative Medicine

Objective: To evaluate the regeneration of mandibular cartilage defect after implantation of human umbilical cord mesenchymal stem cells (hUCMSC) over platelet rich fibrin (PRF) as scaffold. Material and Methods: 20 male Wistar rats were randomly divided into four experimental groups consisting of: a control group featuring untreated mandibular defects (C), experimental groups whose mandibular defects were implanted with hUCMSC (E1), mandibular defects implanted with PRF (E2), mandibular defects implanted with hUCMSC and PRF scaffold (E3). The subjects were sacrificed after six weeks of observation for immunohistochemical examination in order to evaluate the expression of Ki67, Sox9, FGF 18, type 2 collagen, and aggrecan, in addition to histology examination to evaluate chondrocyte number and cartilage thickness. Data was analyzed with univariate analysis (ANOVA). Results: The implantation of hUCMSC and PRF scaffold proved capable of regenerating mandibular cartilage defect through the expression of FGF 18, Sox9, Ki67, chondrosis counts, type 2 collagen, aggrecan, and cartilage thickness. The regeneration were significantly higher in group E3. Conclusion: Human umbilical cord mesenchymal stem cells in platelet rich fibrin scaffold proved capable of regenerating mandibular cartilage defect.

Histologic, Radiographic, and Micro-Computed Tomography Evaluation of Experimentally Enlarged Root Apices in Dog Teeth with Apical Periodontitis after Regenerative Treatment

BackgroundBlood clot (BC) and platelet-rich fibrin (PRF) has been successfully used to biologically treat immature roots. It is nowadays considered the treatment of choice.ObjectiveThis study aimed to determine the ability of PRF and BC scaffolds to enhance regeneration of disinfected root canals and healing of apical periodontitis within experimentally enlarged canal apices of dog teeth.MethodsForty-eight root canals in 28 mandibular premolars from 4 healthy adult dogs were experimentally infected and developed apical periodontitis. The teeth were randomly divided into a control (untreated) group, a disinfection only group, a group that received disinfection and a BC scaffold, and a group that received disinfection and a BC + PRF scaffold. Healing of the apical radiolucency was evaluated by conventional radiography, micro-computed tomography, and histology after 3 months. The data were analyzed by χ2 test.ResultsHealing was achieved in 49% of roots as seen on radiograph and 43% as seen on micro-computed tomography. There was no significant between-group difference in the presence or absence of periapical radiolucency in the mesial roots when seen on conventional images (P = 0.255), but there was a significant difference in the distal roots (P = 0.001); similarly, on micro-computed tomography, there was no significant between-group difference in the mesial roots (P = 0.174) but there was a significant difference in the distal roots (P = 0.001). Histologically, apical closure was significantly not greater in the BC + PRF scaffold group than in the BC scaffold group (P = 0.001).ConclusionsA mix of BC + PRF scaffold did not improve tissue regeneration in experimentally enlarged dog teeth. (Curr Ther Res Clin Exp. 2021; 82:XXX–XXX) © 2021 Elsevier HS Journals, Inc.

Antimicrobial Efficacy of a Novel Antibiotic-Eluting Injectable Platelet-Rich Fibrin Scaffold against a Dual-Species Biofilm in an Infected Immature Root Canal Model.

Background and Aims This study was aimed at evaluating the antibacterial property of an injectable platelet-rich fibrin (I-PRF) scaffold containing triple antibiotic mixture against an Actinomyces naeslundii (A. naeslundii) and Enterococcus faecalis (E. faecalis) biofilm in an infected immature root canal model. Methods A dual-species biofilm was inoculated inside the root canals via a series of centrifugal cycles. The samples were allocated to three experimental groups (i.e., G1: triple antibiotic mixture, G2: I-PRF containing triple antibiotic mixture, and G3: antibiotic-free I-PRF scaffold) and two control groups (G4: seven-day biofilm untreated and G5: bacteria-free untreated). Results Bacterial gene quantification change and the overall reduction of live bacteria were evaluated. The highest antibacterial activity against A. naeslundii belonged to G2. However, G1 and G2 had similar antibacterial property against E. faecalis (p value = 0.814). In general, experimental groups revealed higher levels of antibacterial activity against E. faecalis than against A. naeslundii (p value < 0.001). Notably, G2 could dramatically decrease the number of live bacteria up to near 92%. Conclusions The current study provides insight into the antibacterial property of an antibiotic-eluting I-PRF scaffold against a dual-species biofilm colonized inside the root canal. The fabricated scaffold contains not only the antibiotics but also the growth factors, which favor the regeneration.

Biological effect of the nanocrystalline calcium sulfate bone graft in the periodontal regeneration

BackgroundThe ultimate goal of tissue engineering is to reproduce functional alveolar∖Periodontal complex. This study aimed to asses micro- and nano-formulated crystalline calcium sulfate as possible treatment of intrabony defect utilizing an autologous Platelet rich fibrin scaffold. Subjectsand Methods: An experimental prospective split mouth design using eight healthy mongrel dog’s was conducted. After two months of extracting the first premolar, bilateral intrabony defects were created mesial to the mandibular second premolar. One side was grafted by nanocrystalline calcium sulfate, while, the opposite side was grafted with microcrystalline calcium sulfate graft. Dogs were randomly euthanized after one month (group I) and 3 months (group II). The primary outcomes were the histological changes of new bone formation in hematoxylin and eosin and Masson trichrome stains, while histomorphometric and radiographic analysis were the secondary outcome followed by statistical analysis (P value was set at .05). ResultsThere was a significant increase in the percentage of bone formation in relation to defect height in nanocrystalline compared to microcrystalline form after one month and three months in both histological (p-values of <0.0001) and radiographic results (p-values of <0.0001). ConclusionNanocrystalline calcium sulfate presented a significant enhanced periodontal regeneration compared to the microcrystalline form.

Cytokine and Growth Factor Delivery from Implanted Platelet-Rich Fibrin Enhances Rabbit Achilles Tendon Healing.

Tendons are hypocellular and hypovascular tissues, and thus, their natural healing capacity is low. In this study, we sought to evaluate the efficacy of platelet-rich fibrin (PRF) to serve as a bioactive scaffold in promoting the healing of rabbit Achilles tendon injury. For in vitro study, the essence portion of PRF was determined through bioluminescent assay. Furthermore, we analyzed the time-sequential cytokines-release kinetics of PRF and evaluated their effects on tenocytes proliferation and tenogenic gene expressions. In animal study, the rabbit Achilles tendon defect was left untreated or implanted with normal/heat-denatured PRF scaffolds. Six weeks postoperatively, the specimens were evaluated through sonographic imaging and histological analysis. The results revealed significantly more activated platelets on bottom half of the PRF scaffold. Cytokine concentrations released from PRF could be detected from the first hour to six days. For the in vitro study, PRF enhanced cell viability and collagen I, collagen III, tenomodulin, and tenascin gene expression compared to the standard culture medium. For in vivo study, sonographic images revealed significantly better tendon healing in the PRF group in terms of tissue echogenicity and homogeneity. The histological analysis showed that the healing tissues in the PRF group had more organized collagen fiber, less vascularity, and minimal cartilage formation. In conclusion, bioactive PRF promotes in vitro tenocytes viability and tenogenic phenotypic differentiation. Administration of a PRF scaffold at the tendon defect promotes tissue healing as evidenced by imaging and histological outcomes.

Augmentation of Tendon Graft–Bone Tunnel Interface Healing by Use of Bioactive Platelet-Rich Fibrin Scaffolds

Background: Platelet-rich fibrin (PRF) is a bioactive biomaterial wherein cytokines are enmeshed within the interconnecting fibrin network. PRF can be fabricated into a patch to augment healing of the interface between a tendon graft and bone tunnel. Hypothesis: The bioactivity of a PRF scaffold is preserved after PRF is mechanically compressed into a patch. A bioactive PRF patch could promote the incorporation of a tendon graft within the bone tunnel through the formation of a tendon-bone healing zone composed of both fibrocartilaginous tissue and new bone. Study Design: Controlled laboratory study. Methods: Bioactivity of PRF was evaluated through treatment of rabbit tenocytes with PRF-conditioned medium and cultivation of cells on a PRF patch. Cellular morphologic features, viability, and differentiation were analyzed accordingly. In an animal study, a rabbit tendon-bone healing model was established through use of New Zealand White rabbits. The implanted tendon graft was enveloped circumferentially with a bioactive PRF patch before being pulled through a bone tunnel in the proximal tibia. Micro–computed tomography (micro-CT) imaging and histological and biomechanical analyses of the tendon-bone interface were performed at 12 weeks postoperatively. Results: PRF improved the viability of the cultured tenocytes. The effects of PRF on in vitro mineralization of tenocytes were comparable with the effects of standard culture medium. The gene expressions of type I collagen and osteopontin were upregulated upon PRF treatment. For the in vivo study, micro-CT images revealed significant new bone synthesis at the tendon-bone interface in the PRF-enveloped group. The tendon-bone healing zone was characterized by abundant fibrocartilage tissue and new bone formation as demonstrated by histological analysis. Biomechanical testing showed significantly higher ultimate loads in the PRF-enveloped group. Conclusion: Bioactive PRF could effectively augment healing of tendon graft to bone by inducing the formation of a transitional tendon-bone healing zone composed of fibrocartilage and bone. Clinical Relevance: Complete healing of the tendon graft in the bone tunnel is a prerequisite for successful ligament reconstruction, which would allow early and aggressive rehabilitation and rapid return to preinjury activity level. From a translational standpoint, the PRF-augmented healing in this rabbit animal model showed a promising biological approach to enhance tendon graft to bone healing via promotion of the functional anchorage between the 2 different materials.

Healing of Full-Thickness Wounds Using Platelet-Rich Fibrin Seeded with Adipose Stem Cells in a Diabetic Mouse Model

Diabetic wounds are refractory to spontaneous healing and treatment regimes due to their detrimental nature. Adipose derived stem cells (ASCs) hold great potential in stem cell-based therapies. However, insufficient cell activity and survival after transplantation dramatically reduce the therapeutic effects. Platelet-rich fibrin (PRF) is a great source of growth factors and has been widely used in clinical practice, but few studies explored its application in diabetic wounds. This study was designed to investigate therapeutic effect of PRF as a delivery scaffold of ASCs on promoting healing of diabetic wound in a mouse model. ASCs isolated from subcutaneous fat were cultured in the three-dimensional PRF scaffold for 3 and 7 days, respectively. H&amp;E staining, laser scanning confocal microscopy (LSCM) and scanning electron microscopy (SEM) observation revealed that ASCs could survive and proliferate in PRF. Cell numbers in PRF increased dramatically in the duration of 7 days post-seeding. Meanwhile, it is revealed that conditioned medium of PRF enhanced ASCs proliferation and migration in an in vitro wound model. Furthermore, transplantation of PRF alone or PRF loaded with ASCs improved significantly diabetic wound repair, respectively. Capillary density in wounds received either PRF or PRF-ASCs was significantly higher than wounds without intervention. A in vivo survival assay was also conducted to find that PRF could maintain ASCs cells survive in diabetic wounds. Our study indicated that PRF, in particular that loaded with ASCs, can be considered as a promising approach in the treatment of diabetic wounds.

Pulp Revascularization/Revitalization of Bilateral Upper Necrotic Immature Permanent Central Incisors with Blood Clot vs Platelet-rich Fibrin Scaffolds-A Split-mouth Double-blind Randomized Controlled Trial.

ObjectivesClinical and radiographic evaluation of the regeneration of bilateral necrotic upper permanent central incisors with open apex using blood clot (BC) and platelet-rich fibrin (PRF) scaffolds.Trial designSplit-mouth double-blind parallel arm randomized controlled clinical trial.Materials and methodsRandomization and blinding: The study started with 15 patients with bilateral necrotic upper permanent central incisors with open apex. Computer-generated tables were used to allocate treatments. The two maxillary central incisors were randomly assigned to either the control (BC scaffold) or the examined (PRF scaffold) groups. Participants: Thirteen patients aged 8–14 years fulfilled the study requirements. Follow-up was performed for 3, 6, 9, and 12 months. Standardized radiographs were collected each 3 months, and difference in measurements was calculated using Image J software. Primary outcomes measured were sinus/fistula formation, pain complaint, mobility grade, and swelling presence/absence. Radiographic: Root length elongation and increase in root thickness. Secondary outcomes were sensibility test and crown color change. Radiographic: Change in bone density and apical diameter. Radiographs that were standardized used during the follow-up time, and occurred changes were calculated using Image J software.ResultsOne patient was lost during follow-up; therefore, 24 treated teeth were analyzed, they showed 100% success rate. Platelet-rich fibrin teeth displayed a statistically significant growth in radiographic root length and width, increased periapical bone density, and a reduction in apical diameter when compared with BC. At the end of the follow-up period, all treated teeth were negative to sensibility test. Blood clot displayed greater crown discoloration in comparison to PRF group.ConclusionFor teeth with open apex and necrotic pulp, revascularization using PRF is an appropriate substitute to BC.How to cite this articleRizk HM, Salah AL-Deen MS, Emam AA. Pulp Revascularization/Revitalization of Bilateral Upper Necrotic Immature Permanent Central Incisors with Blood Clot vs Platelet-rich Fibrin Scaffolds—A Split-mouth Double-blind Randomized Controlled Trial. Int J Clin Pediatr Dent 2020;13(4):337–343.

Comparative evaluation of Platelet Rich Plasma (PRP) versus Platelet Rich Fibrin (PRF) scaffolds in regenerative endodontic treatment of immature necrotic permanent maxillary central incisors: A double blinded randomized controlled trial

ObjectivesThe research aims to assess the regenerative potential of Platelet Rich Plasma (PRP) versus Platelet Rich Fibrin (PRF) scaffolds in immature permanent maxillary central incisors with necrotic pulps, clinically and radiographically. Trial designDouble blinded parallel randomized controlled trial was implemented to identify the results. Subject & methodsThe proposed study was conducted among 30 patients with maxillary necrotic permanent immature central incisors but only 26 patients fulfilled the study requirements. Group I was treated with PRP and Group II with PRF scaffolds. Follow up has been done every 3 months for one year. Primary outcomes were measured clinically: Pain, Mobility, Swelling, and Sinus/fistula. Radiographically: increase root length and width. Secondary outcomes were clinically: Discoloration and Sensibility test. Radiographically: increase in bone density measurements and decrease in apical diameter. Standardized radiographs were collected during the follow up period, and radiographic changes were measured by using Image J software. Statistical analysis was performed on 25 patients who had completed the study. ResultsAll 25 patients' teeth were survived during the 12-month follow-up period. PRP showed marginal increase in radiographic root length and width, periapical bone density and a decrease in apical diameter. No statistical significant differences were observed when it was compared with PRF. The teeth which were treated did not respond to sensibility test at the end of the study. PRF displayed statistical significant higher amount of crown discoloration when compared to PRP group. ConclusionsFor necrotic immature teeth, revascularization using PRP is an appropriate alternative to PRF and showed excellent 12-months prognosis.