Coronavirus Disease 19 (COVID-19): Implications for Clinical Dental Care

The recent spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its associated coronavirus disease has gripped the entire international community and caused widespread public health concerns. Despite global efforts to contain the disease spread, the outbreak is still on a rise because of the community spread pattern of this infection. This is a zoonotic infection, similar to other coronavirus infections, that is believed to have originated in bats and pangolins and later transmitted to humans. Once in the human body, this coronavirus (SARS-CoV-2) is abundantly present in nasopharyngeal and salivary secretions of affected patients, and its spread is predominantly thought to be respiratory droplet/contact in nature. Dental professionals, including endodontists, may encounter patients with suspected or confirmed SARS-CoV-2 infection and will have to act diligently not only to provide care but at the same time prevent nosocomial spread of infection. Thus, the aim of this article is to provide a brief overview of the epidemiology, symptoms, and routes of transmission of this novel infection. In addition, specific recommendations for dental practice are suggested for patient screening, infection control strategies, and patient management protocol.

Bangladeshi Medicinal Plant Extracts Inhibiting Molecular Interactions between Nuclear Factors and Target DNA Sequences Mimicking NF-kB Binding Sites

Several medicinal plants can be employed to produce extracts exhibiting biological effects. The aim of this work was to verify the ability of extracts derived from different medicinal plants of Bangladesh in interfering with specific DNA-protein interactions. The rationale for this study is based on the observation that alteration of gene transcription represents a very promising approach to control the expression of selected genes and could be obtained using different molecules acting on the interactions between DNA and transcription factors (TFs). We have analysed the antiproliferative activity of extracts from the medicinal plants Hemidesmus indicus, Polyalthia longifolia, Aphanamixis polystachya, Moringa oleifera, Lagerstroemia speciosa, Paederia foetida, Cassia sophera, Hygrophila auriculata and Ocimum sanctum. Antiproliferative activity was assayed on different human cell lines, including erythroleukemia K562, B-lymphoid Raji, T-lymphoid Jurkat and erythroleukemia HEL cell lines. We employed the electrophoretic mobility shift assay (EMSA) as a suitable technique for the identification of plant extracts altering the binding between transcription factors and the specific DNA elements. We found that low concentrations of Hemidesmus indicus, Polyalthia longifolia, Moringa oleifera and Lagerstroemia speciosa, and very low concentrations of Aphanamixis polystachya extracts inhibit the interactions between nuclear factors and target DNA elements mimicking sequences recognized by the nuclear factor kappaB (NF-kappaB). On the contrary, high amount of extracts from Paederia foetida, Cassia sophera, Hygrophila auriculata or Ocimum sanctum were unable to inhibit NF-kappaB/DNA interactions. Extracts inhibiting both NF-kappaB binding activity and tumor cell growth might be a source for anti-tumor compounds, while extracts inhibiting NF-kappaB/DNA interactions with lower effects on cell growth, could be of interest in the search of compounds active in inflammatory diseases, for which inhibition of NF-kappaB binding activity without toxic effects should be obtained.

Adaptive response of Micrococcus luteus to alkylating chemicals

Wild type M. luteus cells have been adapted by a step-wise treatment with sub-lethal concentrations of MNNG. The adapted cells exhibit 5.7 fold increased resistance to the killing effects of the mutagen and a simultaneous efficient removal of various base modifications present in cellular DNA. A protein extract prepared from adapted cells contains inducible repair functions which can reduce 80-90% of the alkylated DNA content of 06-MeG is effected by a transmethylase and there is no concomitant release of the modified base. However, N-3 MeG is released as a free modified base through the action of a DNA glycosylase. The release of N-3 MeA is unaffected by the induction treatment whereas that of N-7 methylpurine is slightly improved in the adapted cells.

Efficacy of Mouth Rinses Against SARS-CoV-2: A Scoping Review

Introduction:The presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in saliva and nasopharyngeal secretions has challenged the routine practice of dentistry. Use of preprocedural mouth rinses has been recommended by several organizations to potentially reduce the transmission of SARS-CoV-2. This scoping review aimed at evaluating the available evidence on the efficacy of mouth rinses against SARS-CoV-2.

Methods:A thorough literature search on electronic databases (PubMed, Scopus, and Google Scholar) was performed by two independent reviewers and data from articles addressing the aim of this article were extracted.

Results:After exclusion of articles not addressing the end point in question, 12 articles were included in this scoping review. Of the 12 articles, seven werein vitrostudies and five werein vivohuman clinical studies. Thein vitrostudies used a standardized methodology (endpoint dilution assay) to evaluate the efficacy of antimicrobial mouth rinses against SARS-CoV-2. Thein vivostudies were done utilizing polymerase chain reaction assay of samples obtained from saliva or nasopharyngeal swab or a combination of both nasopharyngeal and oropharyngeal swab. The reagents tested in these studies included povidone-iodine, chlorhexidine, hydrogen peroxide (H2O2), essential oils, and quaternary ammonium compounds and demonstrated varied efficacy against SARS-CoV-2.

Conclusion:Based on the available evidence fromin vitrostudies, it can be concluded that mouth rinses have a potential to reduce SARS-CoV-2 viral load; however, effectiveness inin vivoconditions is still inconclusive. Owing to the substantial heterogeneity in reporting of the anti–SARS-CoV-2 efficacy of mouth rinses, this review highlights the need to conduct future research with robust and standardized methodologies to confirm effectiveness of mouth rinses.

Dilemmas pertaining to three canals in the mesiobuccal root of a maxillary second molar: a case report

The mesiobuccal root of the maxillary molars is well known to pose a hindrance during endodontic therapy. Presented here is a case of a maxillary left second molar where three canals were located in its mesiobuccal root with the use of visual and diagnostic aids. Difficulties encountered during the process of unveiling the tooth's internal anatomy were discussed. The dilemmas encountered pertained to the root canal configuration, the nomenclature of the extra canals, and the justification for the presence of a third canal. The root canal configuration of 3-2-1 was confirmed for the mesiobuccal root using information gained from clinical, radiographic, and multi-detector computed tomography (MDCT) scan findings. This case demonstrates the need for efforts to locate extra canals in the mesiobuccal root of the maxillary molars as their internal anatomy remains a mystery.

Pharmacotherapy during Pregnancy: An Endodontic Perspective

Odontogenic pain affects up to 54.9% of pregnant women^1-3. This pain is often associated with pulpal and/or periapical infections that pose risks to women and their fetus. The American Dental Association in collaboration with the American College of Obstetricians and Gynecologists developed a consensus statement to affirm the importance of timely and appropriate oral health care as a critical component of a healthy pregnancy⁴. However, limited knowledge of endodontic procedure safety and related medication use often result in the avoidance of treatment during pregnancy. This article, a collaborative effort by specialists from endodontics, pediatric dentistry, and obstetrics, reviews the current evidence on the safety of medications commonly used in endodontics including local anesthetics, analgesics, anxiolytics, and antibiotics.

Unique case of a geminated supernumerary tooth with trifid crown

Gemination, a relatively uncommon dental anomaly, is characterized by its peculiar representation as a tooth with a bifid crown and a common root and root canal. It usually occurs in primary dentition. To come across gemination in a supernumerary tooth is a rare phenomenon. The purpose of this paper is to present a unique case of hyperdontia wherein gemination in an impacted supernumerary tooth resulted in a trifid crown unlike the usual bifid crown. The role of conventional radiographs as well as computed tomography, to accurately determine the morphology and spatial location, and to arrive at a diagnosis, is also emphasized in this paper.

Effect of chlorine dioxide and sodium hypochlorite on the dissolution of human pulp tissue - An in vitro study

BACKGROUND

Organic tissue dissolution is an important property of an irrigant which aids in the success of root canal treatment. Recent studies have advocated the use of Chlorine dioxide as an endodontic irrigant. The aim of this study is to compare the dissolution efficacy of chlorine dioxide and sodium hypochlorite on human pulp tissue.

METHODS

In this study, 2% Sodium hypochlorite, 5% Chlorine dioxide and isotonic saline solution (control) were used. Thirty human pulp tissue specimens were exposed to three test solutions (n = 10) for 30 min following which the loss of weight was compared from the original weight by using a digital analytical balance.

RESULTS

Sodium hypochlorite was more efficient in dissolving human pulp tissue when compared to Chlorine dioxide. Isotonic saline solution failed to dissolve any of the specimens.

CONCLUSION

5% Chlorine dioxide is capable of dissolving human pulp tissue but sodium hypochlorite was more effective.

Mandibular lateral incisor with four root canals: A unique case of double tooth diagnosed using multidetector computed tomography

Double tooth is a dental anomaly consequent to fusion of two or more teeth or gemination of a single tooth. This report describes a unique case of double tooth in relation to a mandibular lateral incisor exhibiting the presence of four root canals. The role of conventional radiography and advanced three-dimensional imaging techniques in the better assessment of complex root canal systems and their aid in endodontic management has also been highlighted.

Comparative evaluation of 15% ethylenediamine tetra-acetic acid plus cetavlon and 5% chlorine dioxide in removal of smear layer: A scanning electron microscope study

Aims:

The purpose of this study was to compare the efficacy of smear layer removal by 5% chlorine dioxide and 15% Ethylenediamine Tetra-Acetic Acid plus Cetavlon (EDTAC) from the human root canal dentin.

Materials and Methods

Fifty single rooted human mandibular anterior teeth were divided into two groups of 20 teeth each and control group of 10 teeth. The root canals were prepared till F3 protaper and initially irrigated with 2% Sodium hypochlorite followed by 1 min irrigation with 15% EDTAC or 5% Chlorine dioxide respectively. The control group was irrigated with saline. The teeth were longitudinally split and observed under Scanning electron microscope SEM (×2000).

Statistical Analysis Used:

The statistical analysis was done using General Linear Mixed Model.

Results:

At the coronal thirds, no statistically significant difference was found between 15% EDTAC and 5% Chlorine dioxide in removing smear layer. In the middle and apical third region 15% EDTAC showed better smear layer removal ability than 5% Chlorine dioxide.

Conclusion:

Final irrigation with 15% EDTAC is superior to 5% chlorine dioxide in removing smear layer in the middle and apical third of radicular dentin.

Effect of Sodium Hypochlorite in Dental Unit Waterline on Aerosolized Bacteria-Generated from Endodontic Procedures

INTRODUCTION

Aerosol generation in a dental setting is a critical concern and approaches that aim at decreasing bacterial load in aerosols is of high priority for dental professionals. The objectives of this study were to evaluate the relative effect of various endodontic procedures on the generation and dissemination of aerosols and the effect of 0.1% sodium hypochlorite (NaOCl) in dental unit waterlines (DUWLs) on the bacterial load in the generated aerosols in a clinical setting.

METHODS

The study was completed in two phases. The classical passive sampling technique using brain heart infusion agar plates was utilized. Agar plates were strategically placed throughout the operatory at pre-defined locations.

PHASE I

To evaluate the effect of different endodontic procedures on generation and dissemination of aerosols, we collected a total of 38 samples. Following baseline collection, test samples were collected during vital pulp therapy (VPT) full pulpotomy (n=10), non-surgical root canal therapy (NSRCT; n=10), surgical root canal therapy (SRCT; n=10), and incision and drainage (I&D; n=8) procedures. Bacterial growth was expressed as colony-forming units at 48 hours post-sample collection. Data were analyzed using 1-way analysis of variance with Tukey's multiple comparisons post-hoc test.

PHASE II

To evaluate the effect of 0.1% NaOCl in DUWL on the bacterial load in the generated aerosols, a total of 30 samples were collected. All procedures including VPT (n=10), NSRCT (n=10), and SRCT (n=10) were performed with 0.1% NaOCl in DUWL. Bacterial growth was expressed as colony-forming units at 48 hours post-sample collection. Data were analyzed using 2-way analysis of variance with Tukey's multiple comparisons post-hoc test.

RESULTS

All endodontic procedures generated aerosols at all tested locations except I&D. Aerosols were disseminated as far as 3m from the patient's head with no significant difference between various locations (p>0.05). VPT procedures generated the maximum number of aerosols compared to NSRCT and SRCT. Adding 0.1% NaOCl to DUWLs significantly reduced the bacterial load in the generated aerosols in all treatment groups compared to groups treated with untreated waterlines (p<0.05). No significant difference was noted in the bacterial load between all groups with treated waterlines (p>0.05).

CONCLUSIONS

All tested endodontic procedures led to the generation and dissemination of contaminated aerosols, and the addition of 0.1% NaOCl as a biocide to the DUWL led to a statistically significant reduction in the bacterial load.

Lobodontia: the unravelling of the wolf teeth

Abnormalities of tooth shape and size generally coexist, as both are determined during the morphodifferentiation stage of odontogenesis. This report describes a case of lobodontia exhibiting multiple dental anomalies of which, "fang like" cuspids, multituberculism of molars, hypodontia along with severe generalized microdontia are distinctive. Radiographic features, diagnostic convolutions, differential diagnosis and clinical significance have also been highlighted.

A preceptorship programme to learn ultrasonography for diagnosis of giant cell arteritis

OBJECTIVE

Ultrasonography has been proposed as the initial diagnostic modality in suspected giant cell arteritis. Proposed quality standards advocate for a certified sonographer. Currently, there are no formal training programmes, and single educational events do not suffice as certification. We developed a preceptorship programme for diagnostic ultrasonography. Here, we describe its contents and test its efficacy.

METHOD

The programme comprises three stages. The preclinical stage includes machine setting and surface anatomy. Second stage includes supervised assessment, passed via a directly observed procedure form. In the final validation stage, the trainee and trainer perform an ultrasonography examination in succession, with a comparison of the results. For this programme, a scan included all three segments of the superficial temporal artery and all three parts of the axillary arteries. Comparison of the intima-media thickness (IMT) and categorical judgements for the halo sign and final diagnosis were made.

RESULTS

Six trainees have been through this programme so far. A median of 16 ultrasonography examinations was required to reach the validation stage. The mean ± SD IMT in 360 segments, as measured by the trainee and trainer, was 0.45 ± 0.34 and 0.46 ± 0.35, respectively (p = 0.26). The agreement between trainee and trainer for the presence or absence of halo was excellent in 403 segments (κ = 0.91, 95% confidence interval 0.86, 0.96). There was 100% agreement on the final diagnosis.

CONCLUSION

The integration of technical knowledge with practical skills results in a robust training programme, validating trainees to continue scanning independently.