In Vitro Cytotoxicity Evaluation of Three Root-End Filling Materials in Human Periodontal Ligament Fibroblasts

Cytotoxicity and genotoxicity of Bio-C Repair, Endosequence BC Root Repair, MTA Angelus and MTA Repair HP

The aim was to evaluate in vitro cytotoxicity and genotoxicity of Bio-C Repair (BCR), compared to Endosequence BC Root Repair (ERRM), MTA Angelus (MTA-Ang), and MTA Repair HP (MTA-HP). MC3T3 osteoblastic cells were exposed to extracts of the repairing bioceramic cements. After 1, 3, and 7 days, cytotoxicity and genotoxicity were evaluated by MTT and Micronucleus tests, respectively. Cells not exposed to biomaterials were used as a negative control. Data were compared using ANOVA two-way, followed by the Tukey Test (α=5%). MTA-Ang and MTA-HP showed no difference in relation to control regarding cytotoxicity in any experimental times. BCR and ERRM reduced cell viability after 3 and 7 days (p<0.05); however, the reduction caused by BCR was less than that caused by ERRM. Considering the micronucleus formation, all biomaterials caused an increase after 3 and 7 days (p<0.05), being greater for the BCR and ERRM groups. It can be concluded that BCR is non-cytotoxic in osteoblastic cells, as well as MTA-Ang e MTA Repair HP. BCR and ERRM showed greater genotoxicity than others tested biomaterials.

An Updated Review on Properties and Indications of Calcium Silicate-Based Cements in Endodontic Therapy

Regarding the common use of calcium silicate cements (CSCs) in root canal therapy, their position in the context of past and present dentistry agents can provide a better understanding of these materials for their further improvement. In this context, the present review article addresses a wide range of recent investigations in the field of CSC-based products and describes details of their composition, properties, and clinical applications. The need for maintaining or reconstructing tooth structure has increased in contemporary endodontic treatment approaches. This research thus discusses the attempts to create comprehensive data collection regarding calcium ion release, bond strength, alkalinizing activity and bioactivity, and the ability to stimulate the formation of hydroxyapatite as a bioactive feature of CSCs. Sealing ability is also highlighted as a predictor for apical and coronal microleakage which is crucial for the long-term prognosis of root canal treatment integrity. Other claimed properties such as radiopacity, porosity, and solubility are also investigated. Extended setting time is also mentioned as a well-known drawback of CSCs. Then, clinical applications of CSCs in vital pulp therapies such as pulpotomy, apexification, and direct pulp capping are reviewed. CSCs have shown their benefits in root perforation treatments and also as root canal sealers and end-filling materials. Nowadays, conventional endodontic treatments are replaced by regenerative therapies to save more dynamic and reliable hard and soft tissues. CSCs play a crucial role in this modern approach. This review article is an attempt to summarize the latest studies on the clinical properties of CSCs to shed light on the future generation of treatments.

Final Endodontic Irrigation with 2% Peracetic Acid: Antimicrobial Activity and Cytotoxicity

OBJECTIVE

 The aim of present study was to assess the cytotoxicity and antimicrobial efficacy of 2% peracetic acid (PAA) compared with 5.25% sodium hypochlorite (NaOCl) and 2% chlorhexidine (CHX).

MATERIAL AND METHODS

 For the cytotoxicity test, 100 µl of the tested solutions were added in 12 wells with ECV 304 endothelial cells in each group: NaOCl, CHX, and PAA, in addition to the control group. Each solution was evaluated after 24 hours of contact in four dilutions: 0.2, 0.1, 0.05 and 0.025 through mitochondrial function using MTT colorimetric assay. In the antimicrobial evaluation, 40 dentin blocks 5 mm in length and 0.2 g in weight were incubated with 400 µl of Enterococcus faecalis suspension for 21 days at 37°C. The contaminated samples were divided into three experimental groups within 5 minutes of contact: NaOCl group, CHX group, PAA group, as well as the positive control group. The specimens received treatment and were transferred to a tube with saline for serial dilution of the solution and seeding for isolation and colony forming unit (CFU) count.

STATISTICAL ANALYSIS

 The results obtained were expressed as mean (A570 nm) ± standard deviation (SD) and in a multiple linear regression model and multiple comparisons conducted.

RESULTS

 The antimicrobial evaluation revealed that the NaOCl and CHX groups showed a statistically significant difference compared with the control group (p < 0.001), while the PAA reduced only the CFU growth. It can be concluded that, among the agents tested, PAA expressed greater cell viability, followed by CHX and NaOCl. However, it did not show greater antimicrobial activity in vitro in the mature biofilm of Enterococcus faecalis.

Physicochemical Properties of a Bioceramic Repair Material - BioMTA

This study aimed to assess the physicochemical properties of a repair material in the Brazilian market, BioMTA, in comparison to other two materials currently in use (Biodentine and MTA Angelus). The initial setting time was evaluated using Gillmore needle. The pH was measured with a pH-meter after 24 h, 3, 7, 14 and 21 days. The radiopacity was determined using the equivalence in millimeters of aluminum (mm Al) from digitized occlusal radiographs. Solubility was determined after immersion in water for 7 days. The data were analyzed by one-way ANOVA and Tukey tests (a=0.05). The BioMTA initial setting time (5.2 min) was lower than the other materials (p<0.05). All materials showed an alkaline pH at 21 days. At 24 h, BioMTA was the most alkaline material (p<0.05); and at 3, 7, 14 and 21 days there was no difference between BioMTA and Biodentine (p>0.05), both being more alkaline than MTA Angelus (p<0.05). The radiopacity of BioMTA (4.2 mm Al) was significantly higher compared to Biodentine (p<0.05) and lower than MTA Angelus (p<0.05). The solubility of the materials was -4.2%, -1.6% and 4.1% for BioMTA, MTA Angelus and Biodentine, respectively, with a significant difference between them (p<0.05). Therefore, it can be concluded that BioMTA displayed a shorter setting time, an alkaline pH, a higher radiopacity, and a gain in mass.

Therapeutic Potential of Bauhinia forficata Link in Dental Biofilm Treatment

The oral cytotoxicity, antimicrobial and anti-demineralizing effects of a tincture from Bauhinia forficata Link tincture (BFLT) were evaluated in vitro and ex vivo. Susceptibility tests (minimum inhibitory and microbicidal concentrations-MIC and time-kill assay-MMC) were performed against planktonic oral microorganisms. The contents of phenolic compounds were investigated. Cytotoxic potential was evaluated on oral fibroblasts after 1-5 min exposure to BFLT. Blocks of sound bovine enamel (N = 60) were inoculated with a saliva pool and sustained in a multiple plaque growth system for 48 h to form a biofilm. Biofilm blocks were randomly divided into groups-G (n = 10): G1-Baseline (48 h maturation biofilm), G2-BFLT 23.2 mg/mL, G3-Ethanol 81.20 g/mL, G4-Chlorhexidine 0.12%, G5-Growth control, and G6-Blank control. Treatments (50 μL/1 min) were performed once a day for a week. Streptococcus spp. (S) and total microorganism (TM) counts were expressed as Log₁₀ CFU/mL. Biofilm height was evaluated by confocal microscopy analyses (CMA). Final surface hardness was assessed and percentage of microhardness loss (% MHL) was calculated. Results were significant when P < .05. BFLT inhibited all tested microorganisms (MIC = 1.3-23.2 mg/mL) and promoted optical reduction (0.05-0.22 nm) of all microorganisms after 48-h treatment compared with controls. After 5-min treatment, BFLT showed low values of cell death (3.20%). G2-BFLT reduced S (6.61 ± 0.20) and TM (7.14 ± 0.38) compared with G1-Baseline (S = 7.82 ± 0.28; TM = 8.81 ± 0.67) and G5-Growth control (S = 7.48 ± 0.39; TM = 7.89 ± 0.68); but G4-chlororexidine (S = 6.11 ± 0.48; TM = 6.45 ± 0.16) showed the highest antibiofilm activity. CMA was not different among treatment groups. G2 showed lower % MHL compared with G5, although G4 presented the lowest. Results suggest BFLT is beneficial against dental caries, showing antimicrobial effects against a mature dental biofilm and no cytotoxicity.

Comparison between iRoot BP Plus (EndoSequence Root Repair Material) and Mineral Trioxide Aggregate as Pulp-capping Agents: A Systematic Review

INTRODUCTION

iRoot BP Plus, also known as EndoSequence root repair material (EERM) is a premixed bioceramic thick/putty. According to its instruction manual, iRoot BP Plus is composed of tricalcium silicate, zirconium oxide, tantalum pentoxide, dicalcium silicate, calcium sulfate, calcium phosphate monobasic, and filler agents. This systematic review was carried out to evaluate and present the iRoot BP Plus material as a pulp-capping agent.

MATERIALS AND METHODS

A systematic search for articles with the scope of the selection criteria undergoing for data extraction was conducted through electronic databases. Studies on evaluation of the cytotoxicity, bioactivity, and dentinal bridge formation of iRoot BP, iRoot BP Plus, ERRM putty, or ERRM paste (ERRM) on variant human cells were selected for in vitro models, and dentinal bridge formation on human and animals teeth for in vivo models were selected.

RESULTS

A total of 22 articles were discussed in the review, 14 in vitro studies, five in vivo studies, and three articles with both studies. Methyl thiazol tetrazolium was the most used method for evaluating cytotoxicity. As for dentinal bridge formation, histological assessment and micro-Computed tomography were used. Human dental pulp cells (hDPCs) were the most investigated for in vitro models and rats for in vivo models. Except for one study, all studies involved in this review were primarily examining the material and comparing it to different types of mineral trioxide aggregate.

CONCLUSION

iRoot BP, iRoot BP Plus, and ERRM are biocompatible materials that enhance hDPCs and other variant human cells proliferation, migration, attachment adhesion, mineralization, and dentinal bridge formation.

Comparison of the biocompatibility of calcium silicate-based materials to mineral trioxide aggregate: Systematic review

The objective of this systematic review was to evaluate the biocompatibility and interaction of bioceramic materials with animal and human mesenchymal cells in vitro and in vivo and to compare them with mineral trioxide aggregate (MTA). Two independent researchers conducted PubMed/Medline, Web of Science, and Scopus searches to identify studies published in English, without restrictions on year of publication using the following keywords: “root canal sealer,” “root repair material,” “cytotoxicity,” and “bioceramics.” The articles were selected following the PRISMA statement. A total of 1486 titles were identified in the initial search. However, only 18 studies met the inclusion and exclusion criteria. The results showed that bioceramic materials have biological properties similar to those of MTA, including low cytotoxicity as well as promoting cell proliferation and adhesion, low expression of inflammatory cytokines, and reduced pulp inflammation. This systematic review therefore suggests that the choice of repair bioceramic materials or MTA based on biocompatibility should be the professional's decision.

Cytotoxicity of Endodontic Irrigants on Human Periodontal Ligament Cells

Introduction:

Root canal irrigation has an extremely important role in the success of endodontic treatment. During endodontic treatment, the irrigants will be in contact with pulpal and periapical tissues. The purpose of this study was to clarify the potential toxicological implications of NaOCl, EDTA, MTAD, CHX and QMix on periapical and periodontal tissues.

Methods and Materials:

Cytotoxicity of solutions was evaluated on cultured human periodontal ligament (hPDL) that were carefully removed from the middle third of premolar roots. Cytotoxicity of the materials was assessed after 1, 5 and 15 min of exposure using the Mosmann’s Tetrazolium Toxicity (MTT) assay. Optical density of the solution was read at 540-690 nm wavelength. The intensity of color generated correlated with the percentage of viable cells. Data were statistically analyzed using repeated measures ANOVA followed by Bonferroni test.

Results:

The mean percentage of viable cells in all experimental groups was significantly different from sterile saline groups at all time points (P<0.0001). The mean percentage of viable cells significantly decreased over time in MTAD and NaOCl groups. The lowest and highest cytotoxicity belonged to MTAD and EDTA groups, respectively at all the time points (P<0.05).

Conclusion:

MTAD had the lowest cytotoxicity compared to NaOCl, CHX, QMix and EDTA. These impacts have been time dependent. These irrigation fluids may cause unfavorable effects on vital tissues.

Cytotoxicity of New Calcium Aluminate Cement (EndoBinder) Containing Different Radiopacifiers

Abstract This study aimed to evaluate the cytotoxicity of a calcium aluminate cement (EndoBinder) containing different radiopacifiers, Bi2O3, ZnO or ZrO2, compared with Mineral Trioxide Aggregate (MTA). According to ISO 10993-12:2012 (E) recommendations, 0.2 g of each cement were applied in transwell inserts and placed in 24-well culture plates containing 1 mL of culture medium (DMEM). After 24 h of incubation, the extracts (DMEM containing components released from the cements) were applied to immortalized odontoblast-like MDPC-23 cells. Cell viability (MTT test), alkaline phosphatase activity (ALP), total protein production and cell morphology (Scanning Electron Microscopy - SEM) were evaluated. The volume of 50 µL of extract was used to determine the chemical elements released by the cements using Energy Dispersive Spectroscopy (EDS). The following groups were established (n=6): NC - negative control (without treatment); EB - EndoBinder without radiopacifier; EBBO - EndoBinder+Bi2O3; EBZnO - EndoBinder+ZnO; EBZrO - EndoBinder+ZrO2 and WMTA - White MTA. Data were subjected to statistical analysis (Kruskal-Wallis test, level of significance=5%). Cells exposed to the different versions of EndoBinder presented small reduction in viability, total protein production and ALP activity, with values similar to the NC and WMTA groups (p>0.05). Different elements (C, O, Na, Al, P, Si, Cl, Bi, K) released by the cements were detected in the extracts. However, the cells had no significant changes in their morphology. EndoBinder and MTA did not affect negatively the metabolism of the odontoblastic-like cells, showing it to be cytocompatible, irrespective of the used radiopacifier.