Efficacy of i-PRF in regenerative endodontics therapy for mature permanent teeth with pulp necrosis: study protocol for a multicentre randomised controlled trial

Effects of boric acid combined with injectable platelet rich fibrin on the mineralized nodule formation and the viability of human dental pulp stem cells

BACKGROUND

The present study aimed to evaluate the viability of human dental pulp stem cells (hDPSCs) exposed to boric acid (BA) and injectable platelet-rich fibrin (I-PRF).

MATERIALS AND METHODS

hDPSCs were isolated from impacted third molars. Nine milliliters of whole blood was transferred to I-PRF tubes and centrifuged at 700 rpm for 3 minutes. A BA solution was prepared by dissolving BA in a 0.1 g/ml stock solution. The cells were divided into four groups: control, I-PRF, BA, and BA + I-PRF. Cell viability was evaluated using flow cytometry. Mineralized calcium nodules were observed using Alizarin Red staining. The data were analyzed using two-way analysis of variance and Tukey's HSD test (p<0.05).

RESULTS

The highest percentage of viable cells was in the I-PRF group, and the lowest percentage of viable cells was in the BA group at all times. Larger calcium nodules were observed in the BA group compared to the other groups.

CONCLUSION

The use of I-PRF with or without BA had a positive effect on cell viability. BA and I-PRF affected the formation of mineralized calcium nodules. I-PRF and BA may be used in combination because these substances minimally reduce cell viability and promote mineralized nodule formation.

Cone-beam Computed Tomography Evaluation Timings of Closure of Open Apex by Using Deciduous Tooth Pulp Autotransplantation for the Regenerative Endodontic Treatment of Permanent Teeth with Pulp Necrosis

Regenerative endodontic therapy (RET) of young permanent teeth with necrotic pulps and apical periodontitis in young people, deciduous tooth pulp may be utilized as a natural, biologic scaffold. Recent developments in stem cell biology and material sciences are beneficial for new treatment methods. Previously traumatized and necrotic young permanent tooth was treated with RET protocol. In the first visit, irrigation, and placement of triple antibiotic paste dressing were done. After that in the second visit, intracanal medication was removed and whole pulp tissue harvested from the deciduous tooth was transplanted in the young permanent tooth. Following placement of Biodentine® coronal barrier, access cavity was restored with acid-etch resin composite. This case report would highlight favorable outcome of RET using deciduous pulp autotransplantation in young permanent tooth using cone-beam computed tomography for 6 months' follow-up.

The in vitro efficacy of advanced platelet-rich fibrin plus versus injectable platelet-rich fibrin on the proliferation, migration, and differentiation of stem cells from apical papilla

Background/purpose

Platelet-rich fibrin (PRF) is a promising host-derived scaffold for regenerative endodontic treatment. This study investigated the effects of advanced PRF plus (A-PRF+) and injectable PRF (i-PRF) on the proliferation, migration, and differentiation of stem cells from apical papilla (SCAPs).

Materials and methods

A-PRF+ and i-PRF were prepared using a DUO Quattro centrifuge following a standard protocol. A-PRF+ and i-PRF extract were diluted in Dulbecco's modified Eagle's medium and Ham's F-12 medium (DMEM/F12) to produce the experimental culture medium. DMEM/F12 and DMEM/F12 supplemented with 10% foetal bovine serum (FBS) were used as the negative control (NC) and positive control (PC) media, respectively. The proliferative ability of SCAPs was assessed using a counting method (haemocytometer). The migration ability was examined using a scratch-wound assay. Alkaline phosphatase, bone sialoprotein, dentin matrix protein 1, and dentin sialophosphoprotein expression were measured to determine the differentiation ability.

Results

The proliferation, migration, and differentiation of SCAPs in the A-PRF+ group were similar to those of the PC group. In the i-PRF group, the cell number was significantly (p < 0.01) lower than that of the A-PRF+ group on days 8 and 10; the percentage of the scratched area on days 1 and 2 was significantly higher than in the A-PRF+ group (p < 0.05). The mRNA expression levels of biomarkers in the i-PRF group were similar to those in the A-PRF+ group.

Conclusion

Both A-PRF+ and i-PRF induce SCAPs proliferation, migration, and differentiation. However, A-PRF+ was superior in supporting the proliferation and migration of SCAPs.

Comparative evaluation of the osteogenic capacity of second-generation platelet concentrates on dental pulp stem cells - An ex vivo study

Introduction

Clinical evidence of platelet-rich fibrin (PRF) benefits on bone repair is still emerging, prompting researchers to experiment with different PRF formulations as osteoconductive scaffolds.

Aims

This study compared the osteoconductive effects of injectable PRF (i-PRF) and leukocyte-rich PRF (L-PRF) on the differentiation of dental pulp stem cells (DPSCs) into osteoblasts.

Materials and Methods

Blood samples were collected from the volunteers to prepare L-PRF and i-PRF conditioned media (CM) by centrifugation. DPSCs were isolated from impacted third molars and cultured. Proliferation of DPSCs in response to L-PRF and i-PRF was assessed by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Osteoinductive potential was evaluated through alkaline phosphatase (ALP) activity, alizarin red S (ARS) staining, growth factor levels (vascular endothelial growth factor [VEGF], transforming growth factor [TGF-beta]), and cytokine expression (interleukin 6 [IL-6], IL-8) after 7 days.

Results

MTT assay results showed that both L-PRF and i-PRF increased DPSC proliferation relative to the control group. After 7 days in L-PRF and i-PRF CM, DPSCs exhibited increased ALP activity, higher red-colored calcium deposits with ARS staining, and elevated levels of VEGF and TGF-beta. In addition, higher concentrations of inflammatory cytokines IL-6 and IL-8 were observed in both L-PRF and i-PRF compared to the control.

Conclusions

Using both L-PRF and i-PRF as scaffolds can enhance the osteoinductive ability of stem cells, offering a potential strategy for regenerative therapies.

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

INTRODUCTION

The 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.

METHODS

Fifty 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.

RESULTS

The 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).

CONCLUSIONS

According 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.

Insights into Intra Periodontal Pocket Pathogenesis, Treatment, In Vitro-In Vivo Models, Products and Patents, Challenges and Opportunity

Periodontal disease is a multifactorial pathogenic condition involving microbial infection, inflammation, and various systemic complications. Here, a systematic and comprehensive review discussing key-points such as the pros and cons of conventional methods, new advancements, challenges, patents and products, and future prospects is presented. A systematic review process was adopted here by using the following keywords: periodontal diseases, pathogenesis, models, patents, challenges, recent developments, and 3-D printing scaffolds. Search engines used were "google scholar", "web of science", "scopus", and "pubmed", along with textbooks published over the last few decades. A thorough study of the published data rendered an accurate and deep understanding of periodontal diseases, the gap of research so far, and future opportunities. Formulation scientists and doctors need to be interconnected for a better understanding of the disease to prescribe a quality product. Moreover, prime challenges (such as a lack of a vital testing model, scarcity of clinical and preclinical data, products allowing for high drug access to deeper tissue regions for prolonged residence, lack of an international monitoring body, lack of 4D or time controlled scaffolds, and lack of successful AI based tools) exist that must be addressed for designing new quality products. Generally, several products have been commercialized to treat periodontal diseases with certain limitations. Various strategic approaches have been attempted to target certain delivery regions, maximize residence time, improve efficacy, and reduce toxicity. Conclusively, the current review summarizes valuable information for researchers and healthcare professional to treat a wide range of periodontal diseases.

Ortho-Endo Management of Traumatically Intruded Immature Incisors: A Case Report of Novel Interventional Approach With 20 Months Follow-Up

The case report describes the successful interdisciplinary management of a nine-year-old girl who suffered from traumatic intrusion and rotation of her immature teeth with 12 mm apical displacement of teeth 11 and 21 and 10 mm of teeth 12 and 22. It emphasizes the importance of a comprehensive and contemporary approach, which includes orthodontic intervention and regenerative endodontic procedures (REP). The report follows the CARE (case report) guidelines. The patient was initially observed for four weeks to see if there was potential for spontaneous re-eruption. After eight weeks of orthodontic intervention, the rotation was corrected. However, negative pulp sensitivity and external inflammatory (infection-related) resorption (EIR) occurred, which led to REP using injectable platelet-rich fibrin (i-PRF). Follow-ups over 20 months showed the favorable outcomes of the treatment. A long-term perspective is essential in understanding the outcomes and potential complications associated with traumatic dental injuries (TDI) in children. The case report highlights the importance of collaboration between orthodontists and pediatric dentists, among other specialists. It provides valuable insights into the complexities of managing TDI in children and highlights contemporary regenerative strategies as viable solutions.

Technical considerations in obtaining platelet rich fibrin for clinical and periodontal research

Autologous platelet rich fibrin (PRF), is currently being widely used and investigated across the globe by clinicians and periodontal research. The technical aspect required for the procurement of PRF includes revolution per minute (RPM), relative centrifugal force (RCF) or G-force, rotor radius, rotor angle, stability or vibration in the centrifugal machine and material of test-tube, besides the systemic health of the individual may influence the final outcome. Present technical note intends to compile these aspects for better understanding and appropriate outcome while preparing PRF in varying clinical scenarios.

Study of platelet-rich fibrin promoting endothelial cell differentiation and angiogenesis induced by transplantation of adipose-derived stem cells

Diabetic patients are characterized by long wound healing time, and adipose stem cells (ADSCs) can secrete growth factors to promote angiogenesis and improve diabetic wound healing. In this research, we attempted to interrogate the impact of platelet-rich fibrin (PRF) on ADSCs in diabetic wound healing. ADSCs were harvested from human adipose tissues and identified through flow cytometry. After pretreatment with cultured medium supplemented with different concentrations of PRF (2.5%, 5%, and 7.5%), proliferation and differentiation capacity of ADSCs were assessed by CCK-8 assay, qRT-PCR and immunofluorescence (IF), respectively. Tube formation assay measured angiogenesis. Western blot analysis analyzed expression of endothelial markers and the extracellular signal-regulated kinase (ERK) and serine/threonine kinase (Akt) pathways in PRF-induced ADSCs. The CCK-8 experiment indicated that PRF enhanced proliferation of ADSCs in dose-dependent manner, relative to normal control group. The expression of endothelial markers and the capacity of tube formation were significantly promoted by 7.5% PRF. The release of growth factors containing vascular endothelial grow factor (VEGF) and insulin-like growth factor-1 (IGF-1) from PRF was increased with the extension of detection time. When the receptors of VEGF or/and IGF-1 were neutralized, ADSCs differentiation into endothelial cells were obviously inhibited. Additionally, PRF stimulated ERK and Akt pathways, and the inhibitors of ERK and Akt attenuated PRF-induced differentiation of ADSCs into endothelial cells. In conclusion, PRF promoted endothelial cell differentiation and angiogenesis induced by ADSCs in diabetic wound healing, which appears to give guidance for treating patients.

Are platelet concentrate scaffolds superior to traditional blood clot scaffolds in regeneration therapy of necrotic immature permanent teeth? A systematic review and meta-analysis

BACKGROUND

The effectiveness of platelet concentrates in promoting root development of necrotic immature permanent teeth is unclear. The present study evaluated whether the platelet concentrate protocol was superior to the traditional blood clot protocol in regeneration therapy.

METHODS

We searched Electronic databases, such as PubMed, Cochrane Library, ClinicalTrials and EMBASE. Randomized controlled trial studies, cohort studies, case-control studies and cross-sectional studies were included, in which platelet-rich concentrates were tested for periapical healing and root development, with the blood clot treatment protocol as the control group. Clinical and radiographic outcomes were considered. Selected articles were assessed for risk of bias. Pooled risk ratios (risk ratio, RR) were calculated for clinical success, responses to cold and electric pulp tests, periapical lesions, apex closure, root lengthening, and thickening of the dentin walls. Subgroup meta-analysis were conducted according to the type of platelet concentrate used.

RESULTS

Of the 1272 screened studies, 13 randomized controlled studies, 2 case-control studies and 1 cohort study were selected, in which 465 immature necrotic permanent teeth, particularly incisors and premolars, were treated. Of these 465 teeth, 457 (98.2%) in both the control and experimental groups remained clinically asymptomatic for the entire study duration, whereas eight (1.8%) showed signs and symptoms of failure, including spontaneous pain, sensitivity to percussion or reinfection. Compared with control teeth, teeth treated with PRP achieved better apical healing than BC group (RR 1.13, 95% CI 1.01-1.26, P = 0.03), and teeth treated with platelet concentrates showed improved apical closure (RR 1.04, 95% CI 0.86-1.25, P = 0.69), root lengthening (RR 1.01, 95% CI 0.74-1.39, P = 0.93), and thickening of the dentin walls (RR 1.35, 95% CI 0.95-1.93, P = 0.09), although these differences were not statistically significant.

CONCLUSIONS

Platelet concentrates can be used as successful scaffolds for regenerative endodontic treatment of necrotic immature permanent teeth, and PRP as a scaffold may achieve better periapical healing of teeth with periapical inflammation, although they did not differ significantly from conventional blood clot scaffolds in development of the root.

Plasma Rich in Growth Factors in the Treatment of Endodontic Periapical Lesions in Adult Patients: Case Reports

Platelet-rich fibrin (PRF) is an autologous blood concentrate obtained without anticoagulants by centrifugation of patients’ peripheral venous blood. PRF is considered to enhance the formation of new bone. The aim of this manuscript was to present two case reports of permanent teeth with closed apexes with periapical lesions, treated endodontically with the use of PRF. The root canals were mechanically cleaned and shaped with NiTi files and irrigated with 5.25% sodium hypochlorite (NaOCl), 40% citric acid (CA), and triple distillated water. Before the canal systems were obturated, A-PRF was used as a scaffold and was placed below the cementodentinal junction with hand pluggers. Cone beam computerized tomography (CBCT) was used to assess the resolutions of periapical radiolucencies. After 6 months, the measurements of both periapical lesions were significantly reduced. Although the performed root canal treatments (RCTs) can definitely be recognized as successful, it must be emphasized that mechanical shaping and cleaning of the root canals with special disinfecting solutions significantly affect the clinical efficacy of RCT. It seems impossible to state that PRF played a leading role in the healing process of the presented periapical lesions. Further studies must be performed to assess whether RCT of mature teeth with an additional PRF application is superior to RCT performed alone.