Antibacterial effect of chlorhexidine-cetrimide combination, Salvia officinalis plant extract and octenidine in comparison with conventional endodontic irrigants

Antibacterial Effect of Combinations of Salvia officinalis and Glycyrrhiza glabra Hydroalcoholic Extracts against Enterococcus spp

Enterococcus spp. are a common culprit behind the failure of endodontic treatments, primarily due to their notorious resistance to antimicrobial agents. Considering this challenge, this study was conducted to assess the antimicrobial efficacy of a unique blend of hydroalcoholic extracts sourced from Salvia officinalis and Glycyrrhiza glabra against biofilms formed by Enterococcus faecalis and Enterococcus faecium. The chemical composition of these plant extracts was rigorously characterized, with primary compound quantification achieved through high-performance liquid chromatography (HPLC-DAD) analysis. Additionally, this study determined the minimal bactericidal concentrations of these extracts and evaluated their potential to combat biofilms by quantifying colony-forming units per milliliter (CFU/mL). The findings reveal that the simultaneous application of both extracts yielded additive and synergistic effects against E. faecalis and E. faecium, including both ATCC and clinical strains. Impressively, after a 24 h exposure, these extract combinations demonstrated efficacy comparable to that of a 0.12% chlorhexidine solution, establishing a statistically significant difference from the negative control group. Consequently, the concurrent use of these extracts emerges as a promising alternative antimicrobial strategy for addressing Enterococcus spp. in endodontic treatments, holding substantial potential for clinical applications in this context.

Advances in the Role of Sodium Hypochlorite Irrigant in Chemical Preparation of Root Canal Treatment

Irrigation of root canal system is of great significance to the success of endodontic treatment, where sodium hypochlorite (NaOCl) is the most widely used irrigant in chemical preparation. NaOCl functions by eliminating bacterial biofilms and dissolving organic tissue, which may vary according to several factors such as the microbiology of root canal infection and the concentration of the irrigant. It has been proposed that the effectiveness of NaOCl could be enhanced via several methods, including heating the irrigant, applying in conjunction with certain reagents, or activating by agitation techniques. Despite its antibacterial and tissue-dissolving capacities, NaOCl should be used with caution to avoid detrimental effect due to its cytotoxicity and negative effect on dentin properties. In this narrative review, we discussed the factors that affect the properties of NaOCl, the methods to improve its efficacy, and the side effects that might occur in clinical practice.

A Comparative Evaluation of Antibacterial Efficacy of Moringa oleifera Leaf Extract, Octenidine Dihydrochloride, and Sodium Hypochlorite as Intracanal Irrigants against Enterococcus faecalis: An In Vitro Study

Objectives

The aim of this study is to investigate and compare the microbial efficacy of Moringa oleifera leaf extract, octenidine dihydrochloride (OCT), NaOCl, and their combinations as intracanal irrigants against Enterococcus faecalis.

Materials and Methods

Sixty single-rooted mandibular premolars were decoronated followed by root canal preparation. Each root specimen was autoclaved, inoculated with E. faecalis, and incubated at 37°C for 48 hr. Then, the specimens were divided into six groups based on the irrigation solution used: 2.5% NaOCl (Group 1), 0.1% OCT (Group 2), M. oleifera leaves extract (Group 3), a combination of M. oleifera extract and 1.25% NaOCl (Group 4), a combination of M. oleifera extract and OCT (Group 5) and normal saline (Group 6). Microbial samples were taken from each root canal before (S1) and after (S2) irrigation and the bacterial viability was assessed using colony-forming units (CFU) on bile esculin agar plates.

Results

Comparing the number of CFU/ml before and after irrigation showed a significant reduction (P < 0.001) in all studied groups. Comparison between the CFU/ml after irrigation by NaOCl and each of the combination groups showed a significant difference.

Conclusion

M. oleifera leaves extract and 0.1% OCT solutions have antibacterial effect against E. faecalis comparable to 2.5% NaOCl and might be used as root canal irrigants. The combination groups showed better antimicrobial activities than individual irrigants. However, further studies are required to investigate the biocompatibility and possible toxic effects of the tested irrigants.

Antimicrobial stewardship of antiseptics that are pertinent to wounds: the need for a united approach

Long before the nature of infection was recognized, or the significance of biofilms in delayed healing was understood, antimicrobial agents were being used in wound care. In the last 70 years, antibiotics have provided an effective means to control wound infection, but the continued emergence of antibiotic-resistant strains and the documented antibiotic tolerance of biofilms has reduced their effectiveness. A range of wound dressings containing an antimicrobial (antibiotic or non-antibiotic compound) has been developed. Whereas standardized methods for determining the efficacy of non-antibiotic antimicrobials in bacterial suspension tests were developed in the early twentieth century, standardized ways of evaluating the efficacy of antimicrobial dressings against microbial suspensions and biofilms are not available. Resistance to non-antibiotic antimicrobials and cross-resistance with antibiotics has been reported, but consensus on breakpoints is absent and surveillance is impossible. Antimicrobial stewardship is therefore in jeopardy. This review highlights these difficulties and in particular the efficacy of current non-antibiotic antimicrobials used in dressings, their efficacy, and the challenges of translating in vitro efficacy data to the efficacy of dressings in patients. This review calls for a unified approach to developing standardized methods of evaluating antimicrobial dressings that will provide an improved basis for practitioners to make informed choices in wound care.

Effect of duration and dilution on antimicrobial efficacy of octenidine hydrochloride as an intracanal medicament with chitosan carrier against Enterococcus faecalis - A modified direct contact test

BACKGROUND

The ambiguity in key influential factors such as minimal time for effective action, dilution, and need of drug carrier for intracanal medicaments necessitates a microbial analysis that aids in the potential selection of an intracanal medicament for ensuring optimal root canal disinfection.

AIMS

This study aims to evaluate the antimicrobial efficacy of octenidine hydrochloride (OHC) and gold standard calcium hydroxide (Ca(OH) 2) as intracanal medicaments, both independently and along with chitosan (CTS) as medicament vehicle against the common resistant endopathogen - Enterococcus faecalis.

MATERIALS AND METHODS

A modified direct contact microbial test was used to evaluate the amount of surviving bacteria after predetermined contact time (2, 5, 20, and 60 min) and 5-fold serial dilution of the intracanal medicaments. The experiment was carried out under aseptic conditions and performed in triplicate to ensure reproducibility.

STATISTICAL ANALYSIS USED

The results were analyzed by Kruskal-Wallis analysis of variance followed by pairwise comparisons by Mann-Whitney U-test.

RESULTS AND CONCLUSIONS

The results showed that all the four medicament groups were able to show the maximum antimicrobial efficacy against E. faecalis at 60 min time interval and that the antimicrobial efficacy of OHC and Ca(OH) 2 was at its peak when used alone. The study thereby concluded that the addition of CTS as a carrier did not enhance the antimicrobial efficacy of OHC or Ca(OH) 2 against E. faecalis.

Effects of Calcium Hypochlorite and Octenidine Hydrochloride on L929 And Human Periodontal Ligament Cells

Abstract The aim of this study was to assess cytotoxicity and cell migration of calcium hypochlorite [Ca(OCl)2] and octenidine hydrochloride - OCT (Octenisept®, Schülke & Mayr, Norderstedt, Germany) in L929 and human periodontal ligament (hPDL) cells. The cells were exposed to different doses of different solutions: 2.5% and 5% Ca(OCl)2, 0.1% OCT, 2.5% NaOCl and 2% CHX for 10 min. Cell viability was assessed by methyl-thiazol-tetrazolium (MTT) and neutral red (NR) assays, and cell migration was determined by wound-healing assay. Statistical analysis was performed by two-way ANOVA and Bonferroni tests (α=0.05). The MTT and NR assays revealed that 0.1% OCT was less cytotoxic in hPDL cells (p<0.05), followed by 2% CHX and 2.5% Ca(OCl)2 (p<0.05). There was no significant difference between 2.5% NaOCl and 5% Ca(OCl)2 (p>0.05), but these solutions showed greater cytotoxicity than the others. The result was the same for L929 cells, except that there was no significant difference between 2% CHX and 2.5% Ca(OCl)2 (p>0.05). Wound-healing assay in L929 and hPDL cells showed that cell migration of 0.1% OCT, 2% CHX and 2.5% Ca(OCl)2 groups was higher than 5% Ca(OCl)2 and 2.5% NaOCl groups at 24 h (p<0.05). In conclusion, 0.1% OCT had lower cytotoxicity in tested cell lines than CHX, Ca(OCl)2 and NaOCl. Cell migration was higher for 0.1% OCT, 2% CHX and 2.5% Ca(OCl)2. Therefore, in terms of cytotoxicity, OCT and Ca(OCl)2 have the potential to be used as root canal irrigants.

Microbiota in the apical root canal system of tooth with apical periodontitis

Background

Apical periodontitis (AP) is essentially an inflammatory disease of microbial etiology primarily caused by infection of the pulp and root canal system. Variation of the bacterial communities caused by AP, as well as their changes responding to dental therapy, are of utmost importance to understand the pathogensis of the apical periodontitis and establishing effective antimicrobial therapeutic strategies. This study aims to uncover the composition and diversity of microbiota associated to the root apex to identify the relevant bacteria highly involved in AP, with the consideration of root apex samples from the infected teeth (with/without root canal treatment), healthy teeth as well as the healthy oral.

Methods

Four groups of specimens are considered, the apical part of root from diseased teeth with and without root canal treatment, and wisdom teeth extracted to avoid being impacted (tooth healthy control), as well as an additional healthy oral control from biofilm of the buccal mucosa. DNA was extracted from these specimens and the microbiome was examined through focusing on the V3-V4 hypervariable region of the 16S rRNA gene using sequencing on Illumina MiSeq platform. Composition and diversity of the bacterial community were tested for individual samples, and between-group comparisons were done through differential analysis to identify the significant changes.

Results

We observed reduced community richness and diversity in microbiota samples from diseased teeth compared to healthy controls. Through differential analysis between AP teeth and healthy teeth, we identified 49 OTUs significantly down-regulated as well as 40 up-regulated OTUs for AP.

Conclusion

This study provides a global view of the microbial community of the AP associated cohorts, and revealed that AP involved not only bacteria accumulated with a high abundance, but also those significantly reduced ones due to microbial infection.

Electronic supplementary material

The online version of this article (10.1186/s12864-019-5474-y) contains supplementary material, which is available to authorized users.

Antibacterial and Cytotoxic Effects of Moringa oleifera (Moringa) and Azadirachta indica (Neem) Methanolic Extracts against Strains of Enterococcus faecalis

Objective

To evaluate antibacterial and cytotoxic effect of 2 methanolic extracts of Azadirachta indica and Moringa oleifera against strains of Enterococcus faecalis (ATCC 29212) in vitro.

Methods

The methanolic extracts of Azadirachta indica and Moringa oleifera were prepared in vitro. The antibacterial effect of the extracts against Enterococcus faecalis was evaluated using the agar diffusion technique. The minimum inhibitory concentration (MIC) was determined using the microdilution method and the cytotoxicity using the cellular line MDCK.

Results

The methanolic extract with the most antibacterial effect during the first 24 and 48 hours against Enterococcus faecalis was Moringa oleifera, evidencing a growth inhibition zone of 35.5 ± 1.05 and 44.83 ± 0.98, respectively. The MIC for both extracts was 75 µg/ml. The bactericidal effect of the Azadirachta indica extract was found at a concentration of 25 µg/ml and a concentration of 75 µg/ml for Moringa extract.

Conclusions

In conclusion, we demonstrated that the methanolic extract of Azadirachta indica and Moringa oleifera both have an antibacterial effect against Enterococcus faecalis strains during the first 24 and 48 hours. None of the extracts exhibited toxicity against the cell lines under low concentrations.

Tissue reaction to Aroeira (Myracrodruon urundeuva) extracts associated with microorganisms: an in vivo study

Based on aroeira's (Myracrodruon urundeuva) antimicrobial activity and a future trend to compose intracanal medication, the aim of this study was to assess in vivo inflamatory tissue response to the extracts by edemogenic and histological analysis containing inactivated facultative and anaerobic microorganisms. For edema quantification, eighteen animals were divided into three groups (n = 3, periods: 3 and 6 hours) and 0.2 mL of 1% Evans blue per 100 g of body weight was injected into the penile vein under general anesthesia. After 30 min the animals received a subcutaneous injection in the dorsal region of aqueous or ethanolic extract of aroeira or saline (control) containing inactivated bacteria. Samples were collected, immersed in formamide for 72h, and evaluated by spectrophotometry (630 m). For histological analysis, polyethylene tubes with the extracts were implanted in the dorsal of 30 male rats. Analysis of the fibrous capsule and inflammatory infiltrate were performed after 7 and 30 days. The aqueous extract group induced less edema in both postoperative periods compared to the other groups, but the differences were not significant (p > 0.05). Tissue repair was significantly better after 30 days than after 7 days (p < 0.01). The aqueous solution showed less inflammatory response than the ethanolic solution (p < 0.05), with tendency for better results than control after 7 days. After 30 days, the response to both extracts was similar to control. The aqueous and ethanolic aroeira extracts containing inactivated microorganisms showed a trend for better results than saline, even when associated with microorganisms, and facilitated the tissue repair process.

The Effect of Final Rinse Agitation with Ultrasonic or 808 nm Diode Laser on Coronal Microleakage of Root-canal Treated Teeth

INTRODUCTION

This in vitro study aimed at comparing the effect of agitating the final irrigant solutions of root canal by ultrasonic or using 808 nm Diode laser on the apical seal of canal.

METHODS AND MATERIALS

A total of 90 extracted human maxillary central incisors were prepared up to size #45 and were randomly assigned to 4 experimental groups (n=20) and two control groups (n=5) respectively, as follows: I): 3 mL of 5.25% NaOCl was agitated as final irrigant solution with ultrasonic for 30 sec. The ultrasonic tip was 1 mm shorter than the working length, II): 3 mL of 5.25% NaOCl was agitated as final irrigant with 808 nm Diode laser for 30 sec. Fiber tip, placed in 1 mm shorter from working length was spirally moved coronally, III): 3 mL of 17% EDTA was agitated as final irrigant with 808 nm Diode laser for 30 sec and was applied similar to group II, IV): 3 mL of 17% EDTA was stimulated as final irrigant with ultrasonic for 30 sec and was applied similar to I. Apical seal was assessed by Dual Chamber technique using Bovine Serum Albumin protein. Kruskal-Wallis and Mann Whitney tests were used with significance level lower than 0.05% for statistical analysis.

RESULTS

The average leakage in the negative control, positive control, and groups I, II, III, IV were: 0.00, 13.5±5.1, 1.72±2.9, 5.12±5.6, 3.36±3.7, 2.4±4.2, respectively. Statistical analysis showed significant difference between groups (P<0.05). There was a significant difference between groups 1 and 2 in terms of protein leakage.

CONCLUSION

Agitating 5.25% sodium hypochlorite solution as the final irrigant with ultrasonic is more effective in apical leakage reduction compared to other groups.

Identification of a Novel (-)-5-Epieremophilene Synthase from Salvia miltiorrhiza via Transcriptome Mining

Salvia miltiorrhiza, a medicinal plant in China, has been used for thousands of years to treat coronary heart diseases. Although biosynthesis of tanshinones, a group of diterpenoids in S. miltiorrhiza, has been extensively investigated, to date we know little about the formation of monoterpenes and sesquiterpenes in this medicinal plant. Here, we report the characterization of three sesquiterpene synthases, named SmSTPS1, SmSTPS2, and SmSTPS3, which catalyzed the formation of a new compound, (-)-5-epieremophilene. Additionally, the (-)-5-epieremophilene biosynthesis activity of SmSTPS1 was confirmed by transient expression in Nicotiana benthamiana. Despite the similar enzyme activities of SmSTPS1, SmSTPS2, and SmSTPS3, the three (-)-5-epieremophilene synthase genes displayed different spatial expression patterns and responded differently to hormone treatments, implicating their specific roles in plant-environment interactions. Our results provide valuable data to understanding the biosynthesis and composition of terpenes in plant.