Effects of EDTA and saline as the final irrigation in regenerative endodontic procedures on the migration, proliferation, and differentiation of human stem cells from the apical papilla

What is the impact of Endodontic Irrigant Solutions on the Viability of Stem Cells from Apical Papilla in an in-vitro setting: A Systematic Review

Background

The success of regenerative endodontic procedures (REPs) is significantly influenced by the choice of endodontic irrigant solution. However, the impact of these solutions on the viability of stem cells from the apical papilla (SCAP), a critical component of the REP, remains a subject of ongoing debate.

Objective

This study aimed to investigate the effects of various endodontic irrigant solutions on the viability of stem cells from the apical papilla in an in vitro setting.

Methods

A systematic literature search was conducted using databases such as PubMed/Medline, Scopus, the Cochrane Library, Web of Science, Embase, gray literature, and reference lists up to August 2023. The search was limited to in vitro studies investigating the impact of endodontic irrigant solutions on SCAP viability. The risk of bias in these studies was evaluated using the Joanna Briggs Institute's checklist.

Results

Of the 131 articles retrieved, 14 were selected for review. The effects of eighteen different root canal irrigants, such as ethylenediaminetetraacetic acid, sodium hypochlorite, chlorhexidine, and citric acid, on the viability of SCAPs were evaluated. The risk-of-bias analysis showed a high risk in sample randomization and size justification but a low risk in other areas.

Discussion

The effects of endodontic irrigant solutions on the viability of SCAPs are concentration dependent. Concentrations higher than 1.5% sodium hypochlorite, 2 % chlorhexidine, 10 % citric acid, and 2.5 % EDTA significantly reduced cell viability. However, additional research is necessary to determine the effect of these irrigants on tissue regeneration.

Effect of EDTA Activation on Blood Clot Structure in Regenerative Endodontics: A Scanning Electron Microscopy Study

INTRODUCTION

EDTA plays a crucial role in regenerative endodontic therapy (RET) because of its significant biological effects. However, EDTA is also recognized as the preferred anticoagulant for hematologic tests. Thus, this study aimed to assess the influence of different EDTA activation techniques on the morphology of blood clots after conditioning the root canal dentin.

METHODS

Forty extracted human teeth were prepared to simulate immature teeth and divided into the following 5 groups: (1) saline solution (negative control), (2) EDTA 17% + saline solution (CNI), (3) CNI + ultrasonic activation, (4) CNI + Easy clean activation, and (5) CNI + XP-endo Finisher activation. After irrigation, the roots were cleaved, and the root canals were filled with human blood to clot formation. The morphology and density of erythrocytes, platelets, and the fibrin network were observed using a scanning electron microscope. The fibrin network density was classified using a 4-point scale. Data were analyzed using the Friedman test and the Kruskal-Wallis test with Bonferroni adjustment (α = 5%).

RESULTS

All groups exhibited consistent blood clot morphology characterized by a high density of erythrocytes, platelets, and white blood cells throughout the entire length of the root canal. The negative control group showed statistically significant high scores of fibrin density compared with the CNI group in all root thirds (P < .05). However, there was no statistical difference in the scores for the fibrin network density between the groups irrigated with EDTA with and without activation (P > .05).

CONCLUSIONS

EDTA may impair the fibrin network formation compared with the saline group. However, EDTA activation did not significantly change the effects on the blood clot in contact with the conditioned intraradicular dentin.

Regenerative Endodontic Procedures of Immature Permanent Premolars with Periapical Lesions: A Report of Two Cases Using Two Different Materials, 18-Month Follow-Up

Regenerative endodontic procedure is an emerging alternative to traditional therapies for immature teeth with necrotic pulp with or without periapical lesions. This innovative approach, also known as revitalization procedures, is aimed at enhancing canal wall thickness, stimulating root lengthening, and promoting apical closure. The regenerative endodontic procedures involve minimally invasive cleaning to preserve stem cells, stimulation of bleeding and clot formation within the canal, and the use of biomaterials to stimulate differentiation. This method is the first choice in biologically based treatments for immature permanent teeth. We present two successful clinical cases in which regenerative endodontic procedures were performed on permanent premolars with necrotic pulp with symptomatic apical periodontitis and chronic apical abscess due to dens evaginatus. The same procedure was employed for both cases, utilizing two differential materials: ProRoot MTA (Dentsply Tulsa Dental Specialities, USA) and Biodentine™ (Septodont, Saint-Maur-des-Fossés, France). Both cases exhibited positive clinical and radiographic outcomes after an 18-month follow-up period including periapical healing, increased dentin thickness, root lengthening, and apical closure.