The Effect of Advanced Platelet-Rich Fibrin Plus (A-PRF+) on Graft Stability in Dental Implants and Alveolar Ridge Augmentation Procedures: A New Low-Speed Standardized Centrifugation Protocol

Background: Platelet-rich fibrin (PRF) is a concentrate derived from autologous blood, containing platelets, fibrin, and growth factors (GF) obtained through centrifugation. PRF can be mixed with bone replacement material to form sticky bone, which is then introduced into the desired area for stabilizing and graft-covering. Depending on the centrifugation protocol, the effectiveness of the end products can vary. This controlled clinical study examines the impact of our established PRF protocol in alveolar augmentation and dental implant placement on vertical bone loss. Materials and Methods: A total of 362 implants were performed in 170 patients at the Department of Oral and Maxillofacial Surgery at the University Hospital Innsbruck between 2018 and 2021. After accounting for lost implants, we retrospectively evaluated a radiological vertical bone loss exceeding 1 mm in the first year as the primary endpoint. Results: The use of PRF was significantly associated with vertical bone loss > 1 mm (OR = 0.32, 95% CI (0.13-0.81), p = 0.016). There were no significant associations between PRF and the number of implants lost, the type of augmentation, or bone loss. Discussion: A-PRF+ sticky bone grafts, when combined with bone graft materials, show reduced resorption rates, indicating their potential to enhance graft stability in oral implantology. Our data indicate that the Medifuge MF 100 (Silfradent srl, Forlì, Italy) is effective in producing A-PRF+.

Platelet Rich Fibrin Membrane Grafting After Laser Excision for Oral Mucosal Lesions

Platelet rich fibrin (PRF) is a novel surgical biomaterial which has shown immense healing and regenerative potential with diverse clinical applications. Surgical excision is a routinely employed treatment modality for mucosal oral lesions with or without grafting or repair of the base of the wound. We proposed a hypothesis that covering of the base of excised lesion with this platelet rich fibrin membrane can accelerate the rate of physiological healing process and regeneration. To evaluate the role, efficacy, advantages and adverse effects if any, of placement of PRF membrane grafts over surgical excision sites of oral mucosal lesions. Platelet rich fibrin membrane graft was prepared as per recommendation and established protocols. Patients were selected for surgical excision of localized, superficial oral mucosal lesions after meticulous clinical and radiological considerations and informed consent was taken. After laser excision with safe margins, the base of wound was covered with PRF membrane graft, stitched in place by 3-0 vicryl sutures. The operated site was clinically evaluated at regular intervals and a healing score was calculated and statistically tabulated on the basis of various parameters of healing. A total of 34 patients were included in the study with a male preponderance (21 males and 13 females). Satisfactory and clinically acceptable wound healing was observed in most of the patient with minimal morbidities. Surgical site demonstrated good healing score and clinically complete healing with good epithelialisation was achieved in all patients. Platelet rich fibrin membrane is an effective grafting biomaterial after excision of oral mucosal lesions as it enhances the rate of healing with minimal complications. We recommend further multicentre studies with higher sample size to explore its utility and clinical applications in different avenues of oral and head neck surgery.

Platelet-Rich Fibrin Used in Regenerative Endodontics and Dentistry: Current Uses, Limitations, and Future Recommendations for Application

Regenerative endodontics has introduced numerous procedures such as pulp implantation, revascularization, and postnatal stem cell therapy. Revascularization has been successfully implemented clinically nowadays, thus providing dentists with outrageous results. Platelet-rich fibrin (PRF) used either alone or along with bone graft promotes bone growth and vascularization. This matrix promotes migration, cell attachment, and proliferation of osteoblast that leads to bone formation. PRF consists of a packed fibrin complex consisting of leukocytes, cytokines, and glycoproteins such as thrombospondin. The usage of PRF has reported high success rates in surgical cases such as sinus lift procedures, healing of extraction sockets, and management of periapical abscesses. Compared to platelet-rich plasma, PRF is more economical, easy to prepare, and feasible to use in daily clinical practices. Revascularization compromised the induction of a blood clot into the root canal space, which emerged as a clinical triumph. This further led to platelet concentrates as an autologous scaffold on which revascularization could occur. The applications of PRF in regenerative endodontics are numerous, such as an agent for repairing iatrogenic perforation of the pulpal floor and for the revascularization of immature permanent teeth with necrotic pulps. It acts as a matrix for tissue ingrowth. Evidence of progressive thickening of dentinal walls, root lengthening, regression in the periapical lesion, and apical closure was reported. Further studies are needed to clarify the precise mechanism of action of PRF for dental pulp regeneration both in vitro and in vivo. The current review aims at the present uses of PRF in regenerative endodontics dentistry and its application with future recommendations and limitations.

Effect of platelet-rich fibrin versus chitosan-based Axiostat hemostatic agent following dental extraction in cardiac patients on antiplatelet therapy: A comparative study

Background:

Platelet-rich fibrin (PRF) is a biomaterial that promotes wound healing. It has a fibrinous matrix wherein platelets, pro-inflammatory cytokines, and various growth factors along with few cells are entrapped while Chitosan is a naturally occurring cationic biopolymeric material that is derived from an animal product, chitin. It has demonstrated biological properties which include acceleration in wound healing, hemostasis, enhancement of immunological response, mucosal adhesion by eliciting biological responses, and anti-microbial action.

Aim:

The aim of this study was to evaluate the effect of PRF and Axiostat (A chitosan-based product) on hemostasis after tooth extraction among cardiac patients on antiplatelet medication.

Materials and Methods:

This prospective study was carried out on 300 patients undergoing tooth extraction. Participants were divided into two categories (n = 150, respectively) as Group I (PRF dressing) and Group II (Axiostat dressing). Time to achieve hemostasis was observed using a stopwatch. Average pain score calculation was performed using visual analog on the 7-day postoperative period. Descriptive statistics were done, and data analysis was performed using the Mann–Whitney U-test. P < 0.5 and < 0.001 were considered statistically significant and extremely significant, respectively.

Results:

Average pain score was 1.86 ± 0.06 in Group I and 1.05 ± 0.87 in Group II. Thus, lower postoperative pain was seen with Axiostat dressing. Hemostasis was achieved in Group II participants in 1.25 ± 0.06 min and in 1.89 ± 0.54 min in Group I. P < 0.01 was obtained, although no statistically significant difference in postoperative pain scores (P = 0.8) was seen.

Conclusion:

Chitosan is a superior wound dressing material in achieving hemostasis in cardiac patients on antiplatelet medication after tooth extraction.

An Aggressive Central Giant Cell Granuloma of Mandible in an Older Patient Managed Successfully With Marginal Mandibulectomy and Reconstruction With Submental Island Flap

The Central giant cell granuloma (CGCG) is a non-odontogenic, osteolytic lesion of unknown aetiology, which affects the craniofacial region, particularly the anterior mandible. The age group commonly affected is below 30 years, with a distinct female predilection. Histopathological analyses show fibro cellular stroma consisting of evenly distributed multinucleated giant cells, multiple foci of haemorrhage, and focal areas of spicules of newly formed bone. Depending upon the extent, behaviour, and characteristics management varies from non-surgical to surgical approaches. Since CGCG is associated with a higher rate of recurrence, excision by curettage with the removal of peripheral bone margins is the gold standard and radical surgical intervention in aggressive lesions is associated with low recurrences. Reconstruction of the resulting surgical defect is extremely important to restore aesthetics and function. This case report reviews presentation along with currently used therapies for CGCG while describing an uncommon case of locally aggressive CGCG occurring in a 50-year-old female involving the posterior mandibular region, successfully managed with marginal mandibulectomy, curettage and reconstructed with submental island flap with no recurrence during follow up.

Responses of canine periodontal ligament cells to bubaline blood derived platelet rich fibrin in vitro

Platelet-rich fibrin (PRF) promotes wound healing by providing the release of growth factors. Here, the influence of Thai and Murrah bubaline blood derived PRF on canine periodontal ligament cells (cPDLs) was investigated. PRF was prepared from Thai and Murrah buffaloes with single centrifugation. Results demonstrated that Thai bubaline blood derived PRF exhibited fiber-mesh like morphology and contained more platelet entrapment than Murrah bubaline blood derived PRF. Both bubaline PRFs were able to degrade in vitro under condition with trypsin. Thai but not Murrah bubaline blood derived PRF promoted cPDLs proliferation in serum free and 2% serum culture conditions. Correspondingly, the significant upregulation of KI67 mRNA expression was observed in those cells treated with Thai bubaline blood derived PRF. However, both Thai and Murrah bubaline blood derived PRF accelerated cell migration in an in vitro wound healing assay and facilitated cell spreading. Further, cPDLs cultured in osteogenic induction medium supplemented with Thai bubaline blood derived PRF exhibited the increased mineral deposition in vitro. Frozen Thai bubaline blood derived PRF also promoted cell proliferation, KI67 mRNA expression, cell migration, and cell spreading in cPDLs. Taken these evidence together, bubaline blood derived PRF could provide potential benefits for canine periodontal tissue healing.

Comparison of the effect of tranexamic acid at various concentrations on the degradation time of platelet-rich fibrin

This study aimed to compare platelet-rich fibrin (PRF) membranes obtained using a conventional method and those obtained using the tranexamic acid-mixed method at various concentrations in terms of appearance, weight, and degradation period. In this in vitro study, 20 PRF membranes were divided into four groups, including a conventional group manipulated using the conventional method. The remaining groups were prepared using tranexamic acid at concentrations of 50, 150, and 200 mg. The PRF membranes were evaluated for gross weight, degradation period, and daily remaining weight for 28 days. There were no statistically significant differences in gross weight among all the groups (p = 0.985). The 150 and 200 mg groups had a longer degradation period (more than 28 days), which was significantly longer than that of the control and 50 mg groups (p = 0.048). The daily remaining weights of the 150 and 200 mg groups were significantly greater than that of the control group observed from day 13 to the end of the experiment. The tranexamic acid-mixed technique had no effect on the appearance and weight of the PRF membranes. Moreover, the technique could delay their degradation.

Advanced Platelet-Rich Fibrin in Periosteal Inversion Technique for Root Coverage: A Case Report

INTRODUCTION

The management of gingival recession associated with esthetic concerns and root hypersensitivity is challenging, and its sequelae is based on the assessment of etiological factors and the degree of tissue involvement. Procedures using pedicle flaps, free soft tissue grafts, combination of pedicle flaps with grafts, barrier membranes, and the use of platelet concentrates are all effective for this purpose. The use of the third-generation platelet concentrate, advanced platelet-rich fibrin (A-PRF), has evolved as a promising regenerative material for root coverage procedure wherein it acts as a scaffold and also accelerates wound healing due to its dense fibrin meshwork.

CASE PRESENTATION

This case report, discusses treating an isolated maxillary Miller Class I recession in a 25-year-old male patient by a periosteal inversion method along with the A-PRF membrane. A partial thickness flap was reflected; periosteum was inverted; and an A-PRF membrane was placed over the denuded root surface which aided in enhanced regeneration; 100% root coverage was obtained as seen in follow-up visits.

CONCLUSION

The periosteal inversion technique along with an A-PRF membrane seems to be a novel approach in managing an isolated Miller Class I maxillary gingival recession.

Novel transplant of combined platelet-rich fibrin Releasate and bone marrow stem cells prevent bone loss in Ovariectomized osteoporotic mice

BACKGROUND

Osteoporosis is a metabolic bone disorder characterized by deterioration in the quantity and quality of bone tissue, with a consequent increase susceptibility to fracture.

METHODS

In this study, we sought to determine the efficacy of platelet-rich fibrin releasates (PRFr) in augmenting the therapeutic effects of stem cell-based therapy in treating osteoporotic bone disorder. An osteoporosis mouse model was established through bilateral ovariectomy on 12-week-old female ICR (Institute of Cancer Research) mice. Eight weeks postoperatively, the ovariectomized (OVX) mice were left untreated (control) or injected with PRFr, bone marrow stem cells (BMSCs), or the combination of BMSCs and PRFr. Two different injection (single versus quadruple) dosages were tested to investigate the accumulative effects of BMSCS and PRFr on bone quality. Eight weeks after injection, the changes in tibial microstructural profiles included the percentage of bone volume versus total tissue volume (BV/TV, %), bone mineral density (BMD, g/cm3), trabecular number (Tb.N, number/mm), and trabecular separation (Tb.Sp, mm) and bony histology were analyzed.

RESULTS

Postmenopausal osteoporosis model was successfully established in OVX mice, evidenced by reduced BMD, decreased BV/TV, lower Tb.N but increased Tb.Sp. Eight weeks after injection, there was no significant change to BMD and bone trabeculae could be detected in mice that received single-injection regimen. In contrast, in mice which received 4 doses of combined PRFr and BMSCs, the BMD, BV/TV, and TB.N increased, and the TB.Sp decreased significantly compared to untreated OVX mice. Moreover, the histological analysis showed the trabecular spacing become narrower in OVX-mice treated with quadruple injection of BMSCs and combined PRFr and BMSCs than untreated control.

CONCLUSION

The systemic administration of combined BMSCs and PRFr protected against OVX-induced bone mass loss in mice. Moreover, the improvement of bony profile scores in quadruple-injection group is better than the single-injection group, probably through the increase in effect size of cells and growth factors. Our data also revealed the combination therapy of BMSCs and PRFr has better effect in enhancing osteogenesis, which may provide insight for the development of a novel therapeutic strategy in osteoporosis treatment.

Micro-Clotting of Platelet-Rich Plasma Upon Loading in Hydrogel Microspheres Leads to Prolonged Protein Release and Slower Microsphere Degradation

Platelet-rich plasma (PRP) is an autologous blood product that contains a variety of growth factors (GFs) that are released upon platelet activation. Despite some therapeutic potential of PRP in vitro, in vivo data are not convincing. Bolus injection of PRP is cleared rapidly from the body diminishing its therapeutic efficacy. This highlights a need for a delivery vehicle for a sustained release of PRP to improve its therapeutic effect. In this study, we used microfluidics to fabricate biodegradable PRP-loaded polyethylene glycol (PEG) microspheres. PRP was incorporated into the microspheres as a lyophilized PRP powder either as is (powder PRP) or first solubilized and pre-clotted to remove clots (liquid PRP). A high PRP loading of 10% w/v was achieved for both PRP preparations. We characterized the properties of the resulting PRP-loaded PEG microspheres including swelling, modulus, degradation, and protein release as a function of PRP loading and preparation. Overall, loading powder PRP into the PEG microspheres significantly affected the properties of microspheres, with the most pronounced effect noted in degradation. We further determined that microsphere degradation in the presence of powder PRP was affected by platelet aggregation and clotting. Platelet aggregation did not prevent but prolonged sustained PRP release from the microspheres. The delivery system developed and characterized herein could be useful for the loading and releasing of PRP to promote tissue regeneration and wound healing or to suppress tissue degeneration in osteoarthritis, and intervertebral disc degeneration.

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.

Pilot Study on Fibrin for Chronic Wound Healing

The chronic wound in legs due to vascular abnormalities occurs in 1% to 2% of the adult population. The current treatments are unsatisfactory, and new approaches should be studied. We report in this article a case of a 52-year-old man with a chronic venous wound at the tibia, which has been conventionally treated for nine years. With six weeks of treatment with the autologous fibrin membrane, we were able to identify scar tissue and vascularization, which are characteristic of a healing process.

Assessment of platelet-rich fibrin in the maintenance and recovery of cell viability of the periodontal ligament

This study analyzed the efficacy of autologous platelet-rich fibrin (PRF) in maintaining and recovering cell viability of the periodontal ligament (PDL). The PDL cells were isolated from 45 extracted teeth randomly distributed among 6 groups: 5 min, 1 h, 2 h, PRF 30 min, PRF 1 h and PRF 2 h. In the groups 5 min, 1 h and 2 h (n = 5), the teeth were kept dry in extra-alveolar times of 5 min, 1 h and 2 h respectively. The teeth of the groups PRF 30 min, PRF 1 h and PRF 2 h (n = 10) were kept dry at extra-alveolar times of 30 min, 1 and 2 h followed by immersion in PRF for 45 min. PDL cells were isolated by enzymatic digestion with type II collagenase and dispase, counted and analyzed for viability with Trypan blue vital dye in Neubauer chamber. The variables total number of cells and cell viability demonstrated that in the 5 min, 1 h and 2 h groups there was a decrease after the extra-alveolar dry times of 1 and 2 h. In comparison with the total number of cells, group 1 h, considered immediate reimplantation, did not present statistical difference when compared to the groups PRF 30 min, PRF 1 h and 2 h, a result that demonstrates that PRF assists in cell maintenance and recovery. PRF provided increased cell viability in relation to the different dry extra-alveolar times analyzed (p < 0.001). Autologous PRF presented effectiveness in maintaining and recovering PDL cells from extracted teeth and kept dry for up to 2 h.

Biological approach in repair of partially inflamed dental pulp using second-generation platelet-rich fibrin and mineral trioxide aggregate as a pulp medicament in primary molars

AIM

The purpose of this study was to evaluate and compare clinically and radiographically PRF, MTA and Ca(OH)2 as a pulp dressing material in primary molars.

MATERIAL AND METHODS

The study was conducted on 30 children between 6-9 years of age. Pulpotomy was performed using MTA(Gp I), PRF + MTA(Gp II) and PRF +Ca(OH)₂(Group III). The teeth were evaluated clinically and radiographically after 1,3 and 6 months and were subjected to statistics analysis.

RESULTS

After 6 months follow-up the overall success rate was found to be highest in Gp I with success rate of 97% followed by Gp II 95% and Gp III 78.3%. The results were found to be statistically insignificant (P ≤ 0.05).

CONCLUSION

All materials used in the present study were equally effective as the success rates are statistically insignificant.

Utilizing platelet-rich fibrin bioscaffold at the graft site improves the structure and function of mice ovarian grafts

Aim: The effect of platelet-rich fibrin (PRF) bioscaffold on the structure and function of mice-autotransplanted ovaries was investigated. Materials & methods: Mice were divided into three groups: control, autografted and autografted + PRF bioscaffold. Angiogenesis, ovary histology and serum biochemical factors were assessed. Results: The total volume of the ovary, the number of follicles and the level of superoxide dismutase activity, total antioxidant capacity, IL-10, progesterone and estradiol were significantly higher in the autografted + PRF bioscaffold group compared with the autografted group. In the autografted + PRF bioscaffold group, angiogenesis was accelerated and apoptosis rate, IL-6, TNF-α, malondialdehyde concentrations were significantly lower compared with the autografted group. Conclusion: PRF bioscaffold improves the structure and function of mice-autografted ovary.

Platelet-Rich Plasma for the Treatment of Tissue Infection: Preparation and Clinical Evaluation

IMPACT STATEMENT

The clinical application of platelet-rich plasma (PRP) has been widely studied for its effects on trauma or injury repair/regeneration, however the antibacterial property of PRP has been overlooked. Increasing evidence suggests PRP as a good antibacterial agent and that it could help prevent/treat tissue infection. This review emphasizes the importance of PRP's antibacterial property and summarizes the preclinical and clinical findings regarding the application of PRP in the prevention and treatment of wound and bone infection. The use of biocompatible PRP may be advantageous for tissue infection treatment due to its inherent antibacterial and healing promoting properties.

Biological and Mechanical Properties of Platelet-Rich Fibrin Membranes after Thermal Manipulation and Preparation in a Single-Syringe Closed System

Platelet-rich fibrin (PRF) membrane is a three-dimensional biodegradable biopolymer, which consists of platelet derived growth factors enhancing cell adhesion and proliferation. It is widely used in soft and hard tissue regeneration, however, there are unresolved problems with its clinical application. Its preparation needs open handling of the membranes, it degrades easily, and it has a low tensile strength which does not hold a suture blocking wider clinical applications of PRF. Our aim was to produce a sterile, suturable, reproducible PRF membrane suitable for surgical intervention. We compared the biological and mechanical properties of PRF membranes created by the classical glass-tube and those that were created in a single-syringe closed system (hypACT Inject), which allowed aseptic preparation. HypACT Inject device produces a PRF membrane with better handling characteristics without compromising biological properties. Freeze-thawing resulted in significantly higher tensile strength and higher cell adhesion at a lower degradation rate of the membranes. Mesenchymal stem cells seeded onto PRF membranes readily proliferated on the surface of fresh, but even better on freeze/thawed or freeze-dried membranes. These data show that PRF membranes can be made sterile, more uniform and significantly stronger which makes it possible to use them as suturable surgical membranes.

Angiogenic Properties of 'Leukocyte- and Platelet-Rich Fibrin'

Leukocyte- and Platelet-Rich Fibrin (L-PRF) is an autologous platelet concentrate, consisting of a fibrin matrix enriched with platelets, leukocytes and a plethora of cytokines and growth factors. Since L-PRF is produced bedside from whole blood without the use of an anti-coagulant, it is becoming a popular adjuvant in regenerative medicine. While other types of platelet concentrates have been described to stimulate blood vessel formation, little is known about the angiogenic capacities of L-PRF. Therefore, this study aimed to fully characterize the angiogenic potential of L-PRF. With an antibody array, the growth factors released by L-PRF were determined and high levels of CXC chemokine receptor 2 (CXCR-2) ligands and epidermal growth factor (EGF) were found. L-PRF induced in vitro key steps of the angiogenic process: endothelial proliferation, migration and tube formation. In addition, we could clearly demonstrate that L-PRF is able to induce blood vessel formation in vivo, the chorioallantoic membrane assay. In conclusion, we could demonstrate the angiogenic capacity of L-PRF both in vitro and in vivo, underlying the clinical potential of this easy-to-use platelet concentrate.

STITCHLESS Percutaneous Endoscopic Cervical Discectomy: Are We Moving Towards Day Care Discectomy Procedure?

BACKGROUND

STITCHLESS percutaneous endoscopic cervical discectomy s[PECD] is safe, precise, targeted, and a complete endoscopic procedure to treat soft cervical disc herniation with unilateral radiculopathy. It allows direct visualization of herniated fragment and its removal, inspection of decompressed nerve root in an awake and aware patient. It reduces the risk related to general anesthesia and to the neurological structures. However, all the patients treated with PECD can be candidates for anterior cervical discectomy and fusion (ACDF). ACDF requires a longer period of stay, expense, and more risk to neurological structures and ultimately loss of the disc space by fusion.

MATERIALS AND METHODS

Twenty consecutively treated patients by sPECD over a period of 2 years with soft cervical disc herniation and unilateral radiculopathy were included in the study. PECD enables removal of offending fragment under vision and irrigation and ablation of inflammation with few complications. All patients were followed for minimum of 6 months with visual analog score (VAS) and neck disability index (NDI).

RESULTS

All treated patients had a good outcome in terms of pain relief (VAS) and functional recovery (NDI). One patient had episodes of cough lying in the supine position and another patient had transient hoarseness of voice, (both recovered).

CONCLUSION

Potential benefits of sPECD include safety as it is done under local anesthesia, smaller incision, short hospitalization, fewer complications, avoidance of fusion, preservation of segmental motion, preventing the adjacent segment degeneration, and avoidance of the risk related to the hardware (nonunion and pseudarthrosis). sPECD is an effective treatment modality for soft cervical disc herniation.

Alteration of blood clot structures by interleukin-1 beta in association with bone defects healing

The quality of hematomas are crucial for successful early bone defect healing, as the structure of fibrin clots can significantly influence the infiltration of cells, necessary for bone regeneration, from adjacent tissues into the fibrin network. This study investigated if there were structural differences between hematomas from normal and delayed healing bone defects and whether such differences were linked to changes in the expression of IL-1β. Using a bone defect model in rats, we found that the hematomas in the delayed healing model had thinner fibers and denser clot structures. Moreover, IL-1β protein levels were significantly higher in the delayed healing hematomas. The effects of IL-1β on the structural properties of human whole blood clots were evaluated by thrombelastograph (TEG), scanning electronic microscopy (SEM), compressive study, and thrombolytic assays. S-nitrosoglutathione (GSNO) was applied to modulate de novo hematoma structure and the impact on bone healing was evaluated in the delayed healing model. We found that GSNO produced more porous hematomas with thicker fibers and resulted in significantly enhanced bone healing. This study demonstrated that IL-1β and GSNO had opposing effects on clot architecture, the structure of which plays a pivotal role in early bone healing.

Current overview on challenges in regenerative endodontics

INTRODUCTION

Regenerative endodontics provides hope of converting the non-vital tooth into vital once again. It focuses on substituting traumatized and pathological pulp with functional pulp tissue. Current regenerative procedures successfully produce root development but still fail to re-establish real pulp tissue and give unpredictable results. There are several drawbacks that need to be addressed to improve the quality and efficiency of the treatment.

AIM

The aim of this review article is to discuss major priorities that ought to be dealt before applications of regenerative endodontics flourish the clinical practice.

MATERIALS AND METHODS

A web-based research on MEDLINE was done using filter terms Review, published in the last 10 years and Dental journals. Keywords used for research were "regenerative endodontics," "dental stem cells," "growth factor regeneration," "scaffolds," and "challenges in regeneration." This review article screened about 150 articles and then the relevant information was compiled.

RESULTS

Inspite of the impressive growth in regenerative endodontic field, there are certain loopholes in the existing treatment protocols that might sometimes result in undesired and unpredictable outcomes.

CONCLUSION

Considerable research and development efforts are required to improve and update existing regenerative endodontic strategies to make it an effective, safe, and biological mode to save teeth.