In vitro cytotoxic and non-genotoxic effects of gutta-percha solvents on mouse lymphoma cells by single cell gel (comet) assay

Comparative Cytotoxicity of Menthol and Eucalyptol: An In Vitro Study on Human Gingival Fibroblasts

The aim of this study was to assess the influence of eucalyptol and menthol on the cell viability, migration, and reactive oxygen species production of human gingival fibroblasts (GFs) in vitro. Three different concentrations of eucalyptol and menthol were prepared following ISO 10993-5 guidelines (1, 5, and 10 mM). GFs were isolated from extracted teeth from healthy donors. The following parameters were assessed: cell viability via MTT, Annexin-V-FITC and 7-AAD staining, and IC50 assays; cell migration via horizontal scratch wound assay; and cell oxidative stress via reactive oxygen species assay. Data were analyzed using one-way ANOVA and Tukey's post hoc test. Statistical significance was established at p < 0.05. Eucalyptol and Menthol exhibited high cytotoxicity on gingival fibroblasts, as evidenced by cytotoxicity assays. Eucalyptol showed lower levels of cytotoxicity than menthol, compared to the control group. The cytotoxicity of the tested substances increased in a concentration-dependent manner. The same occurred in a time-dependent manner, although even 10 min of exposure to the tested substances showed a high cytotoxicity to the GFs. Commercially available products for oral application with these substances in their composition should be tested for cytotoxicity before their use.

Are Endodontic Solvents Cytotoxic? An In Vitro Study on Human Periodontal Ligament Stem Cells

The aim of this study was to assess the influence of eucalyptol, chloroform, and Endosolv on the proliferative capability, cell viability, and migration rates of human periodontal ligament stem cells (hPDLSCs) in vitro. Solvent eluates were formulated following ISO 10993-5 guidelines, and 1%, 0.25%, and 0.1% dilutions were prepared. The HPDLSCs were isolated from the extracted third molars of healthy donors. The following parameters were assessed: cell viability via trypan blue and IC50 assays, cell migration via horizontal wound healing assay, cell morphology via cell cytoskeleton staining (phalloidin labeling), and cell oxidative stress via reactive oxygen species assay. The data were analyzed using one-way ANOVA and Tukey’s posthoc tests, and their significance was established at p < 0.05. Chloroform and eucalyptol exhibited significantly higher cytotoxicity on the hPDLSCs in vitro compared to the control group, as shown by the cell viability, migration, morphology, and reactive oxygen species release assays. Alternatively, Endosolv showed adequate cytotoxicity levels comparable to those of the control group. The cytotoxicity of the tested endodontic solvents increased in a dose-dependent manner. The results from the present study highlight the cytotoxicity of chloroform and eucalyptol. Thus, their limited and cautious use is recommended, avoiding solvent extrusion.

The Novel Role of Solvents in Non-Surgical Endodontic Retreatment

Non-surgical endodontic retreatment is a reliable conservative option for managing post-treatment apical periodontitis. However, effective microbial control, based on the maximization of filling removal and disinfection protocols, is not yet predictable. Traditional gutta-percha solvents, which are indistinctively used for both the core and sealer filling materials, became obsolete due to unprecedented advances in endodontic technology. Nonetheless, microtomography, scanning electronic microscopy findings, and histobacteriological analysis tend to confirm the persistence of filling materials and the lack of association between root canal enlargement and superior disinfection. There is a controversy regarding the most suitable clinical protocols surrounding the shaping procedures and the supplementary disinfection steps. Based on the literature and the previous work of the team, the authors aimed to summarize the current knowledge regarding specific solvent formulations that target filling materials. Additionally, the advantage of an additional irrigation step to optimize disinfection was highlighted. This adjunctive procedure serves a dual role in the dissolution of filling materials, and in conferring an antibiofilm effect. Further research is needed to understand the novel contribution of these strategies upon clinical practice outcomes.

A comparative study of the effects of gutta-percha solvents on human osteoblasts and murine fibroblasts

We aimed to investigate the in vitro physiologic effects of xylene, chloroform, orange oil and eucalyptus oil solvents for dissolving gutta-percha on L929 and HOB cell lines; 2.5 and 10 μL mL^-1 of these solvents were tested for 24, 48 and 72 h. Gutta-percha solvents inhibited the proliferation rate of fibroblasts in a dose- and time-dependent manner; however, no inhibition was detected in HOB (evaluated using MTT assay). None of the solvents induced apoptosis/necrosis in HOB cells at ≤2.5 μL mL^-1 concentration in contrast to L929 (determined using acridine orange/ethidium bromide dual staining). Each solvent tested reduced the migration rate of both L929 and HOB cell lines in a dose-dependent manner (evaluated using a scratch assay). Gutta-percha solvents can damage fibroblast-rich tissues. Osteoblasts seemed to be more resistant to the tested solvents, and excessive extrusion of solvents from the root canal may also damage the periradicular tissues and reduce the ability to repair.

Factorial design-optimized and gamma irradiation-assisted fabrication of selenium nanoparticles by chitosan and Pleurotus ostreatus fermented fenugreek for a vigorous in vitro effect against carcinoma cells

The novelty of the present work looks in the synthesis of aqueous dispersed selenium nanoparticles (Se NPs) using gamma rays with the aid of various natural macromolecules such as citrus pectin (CP), sodium alginate (Alg), chitosan (CS) and aqueous extract of fermented fenugreek powder (AEFFP) using Pleurotus ostreatus for investigating their impact in vitro toward carcinoma cell. The synthesized Se NPs were characterized by XRD, UV-Vis., DLS, HRTEM, SEM, EDX and FTIR. Nucleation and growth mechanisms were also discussed. The factorial design was applied to examine the importance of multiple parameters on Se NPs production with a special focus on temperature and gamma rays influences. FTIR spectrum exhibited the existence of several functional groups in Se NPs-capping macromolecules. Results revealed that Se NPs' size was dramatically-influenced by the type of stabilizer, precursors concentration, pH and the absorbed gamma rays dose. The current research reported the promising antitumor application of Se NPs against Ehrlich Ascites Carcinoma (EAC) and human Colon Adenocarcinoma (CACO) in vitro. The proliferation of EAC was significantly-hindered by Se NPs-CS (38.0 μg/ml) at 60 kGy (IC₅₀ = 23.12%) and Se NPs-AEFFP (19.00 μg/ml) at 15 kGy (IC₅₀ = 7.21%). Also, Se NPs control the generation of CACO cells, IC₅₀ was recorded as 25.32% for Se NPs-CS (38.0 μg/ml) and 8.57% for Se NPs-AEFFP (19.00 μg/ml).

Antimicrobial, antioxidant and anticancer activities of zinc nanoparticles prepared by natural polysaccharides and gamma radiation

Aqueous dispersed zinc nanoparticles (ZnNPs) were synthesized using natural polysaccherides (chitosan (CS), citrus pectin (CP) and alginate (Alg)) using aqueous fermented fenugreek powder (FFP) by Pleurotus ostreatus as reducing and stabilizing agent or using gamma irradiation. The synthesized ZnNPs are characterized by ultra violect spectroscopy (UV), Transmission electronmicroscopy (TEM), Dynamic light scattering (DLS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). XRD analysis of the ZnNPS confirmed the formation of metallic nanoparticles. The nucleation and growth mechanism of ZnNPs is also discussed. TEM showed that the average diameter of ZnNPs was in the range of 46nm. The size of nanoparticles is influenced by certain parameters such as the choice of stabilizer, pH during synthesis and absorbed dose. Evaluating the antioxidant and anticancer activities of ZnNPs was performed. The results indicating the ZnNPs synthesized by aqueous fermented fenugreek extract have high activity and the average size is 46nm. The results explored that ZnNPs show anticancer activity against Ehrlich Ascites Carcinoma (EAC) and human colon adenocarcinoma (CACO) and the IC_50% was 47.5μg/ml and 65μg/ml respectively. Also, ZnNPs had excellent bactericidal activity against gram positive and negative bacteria and yeast.

A convenient synthesis and molecular modeling study of novel pyrazolo[3,4-d]pyrimidine and pyrazole derivatives as anti-tumor agents

An efficient method to obtain ethyl 5-amino-1-tosyl-1H-pyrazole-4-carboxylate (3) was outlined using condensation reactions of 4-methylbenzenesulfonylhydrazide with (E)-ethyl 2-cyano-3-ethoxyacrylate. The cyclocondensation reaction of this substrate and its hydrazide derivative with urea, thiourea, formamide, formic acid, d-glucose, o-phenylenediamine, 4-dimethylaminobenzaldehyde, anthracene-9-carbaldehyde, thioglycolic acid and carbon disulphide then with hydrazine hydrate analogues furnished a series of pyrazolo[3,4-d]pyrimidine, pyrazolo[3,4-d]oxazin-4-one, pyrazole-4-glucoside, 4-benzo[d]imidazole, 1,3-thiazolidinone, 1,3,4-oxadiazol-2(3H)-thione and 1,2,4-triazol-5(4H)-thione derivatives respectively. The structure of the compound 3 was supported by X-Ray crystallographic data. Orally administrated, one of each of the series of pyrazoles showed significant effects in mouse tumor model cancer cell lines (EAC) and two human cancer cell lines of Colon cancer (HCT-29) and Breast cancer (MCF-7) with docking studies.

Efficacy of grapefruit, tangerine, lime, and lemon oils as solvents for softening gutta-percha in root canal retreatment procedures

AIM

In the present study, we evaluate the efficiency of four kinds of oil as solvents for softening gutta-percha in root canal retreatment procedures. The performance of grapefruit, tangerine, lime, and lemon oils specifically were evaluated and compared to chloroform.

METHODS

Eighty-four cylinder-shaped glass tubes (5 × 30 mm) were filled with gutta-percha. A total of 0.1 mL solvent was added to the upper part of the glass tubes. After 5 min, the spreader attached to the universal testing machine was moved downward through gutta-percha with header speed of 5 mm/min into a depth of 5 mm. An initial depth of spreader penetration without force produced was recorded in millimeters. The load used to penetrate the spreader into the 5-mm depth was recorded in Newton.

RESULTS

The results of the surface-dissolving depth and maximum force used to penetrate the spreader to 5 mm revealed that chloroform was significantly the best solvent in softening gutta-percha (P < 0.05), followed by grapefruit oil and tangerine oil, while the least effective solvents were lime oil and lemon oil.

CONCLUSIONS

Under the conditions of the present study, grapefruit oil and tangerine oil performed best as gutta-perch solvents among four natural oils.

Effectiveness of three solvents and two associations of solvents on gutta-percha and resilon

This study evaluated the effectiveness of 3 solvents (Citrol orange oil, Eucalyptol and Tetrachloroethylene) and 2 associations of solvents (Citrol orange oil+Tetrachloroethylene and Eucalyptol+Tetrachloroethylene) on 3 types of gutta-percha (conventional, thermoplastic and EndoREZ) and Resilon. Ten discs (10 mm diameter x 1 mm thick) from each material were prepared using standard metallic molds. Each specimen was weighed to determinate its initial mass. The specimens were immersed in the solvents for 10 min, followed by immersion in distilled water for 20 min, and were then reweighed to obtain the final mass. The mean weight loss determined the solvent capacity. Data were analyzed by ANOVA and Tukey's test at 5% significance level. Tetrachloroethylene was the most effective on conventional gutta-percha (p<0.05). Tetrachloroethylene was also the most effective on thermoplastic gutta-percha, but it was not significantly different (p>0.05) from Eucalyptol+Tetrachloroethylene, Citrol+Tetrachloroethylene, and Citrol. All solvents and associations presented little effectiveness on Resilon. The association Eucalyptol+Tetrachloroethylene was the most effective on EndoREZ, but it did not differ significantly (p>0.05) from Citrol+Tetrachloroethylene and Tetrachloroethylene. All evaluated substances presented solvent action. Tetrachloroethylene improved the effectiveness of both Citrol and Eucalyptol.