Attributes of dysgeusia and anosmia of coronavirus disease 2019 (COVID-19) in hospitalized patients.

OBJECTIVES: While chemosensory dysfunctions, dysgeusia and anosmia/hyposmia, are recognized as distinctive symptoms of COVID-19, their temporality of presentation and association with the patient age, gender, disease severity, and comorbidities has been sparsely studied. Hence, we evaluated the latter associations of chemosensory dysfunction, in hospitalized COVID-19 patients in the United Arab Emirates (UAE). MATERIALS AND METHODS: Information on chemosensory dysfunction and history of chronic systemic comorbidities, if any, was obtained from 149 COVID-19 patients in an infectious disease hospital in UAE, using their medical records, as well as from a face-to-face questionnaire survey. Additionally, a modified SNOT-22 questionnaire that measures disease-specific quality of life in patients with upper respiratory tract affections was also administered. RESULTS: Chemosensory dysfunction was reported by 94.6% of the cohort, and anosmia with dysgeusia was significantly more in males than females with severe COVID-19. Males with moderate COVID-19 and systemic comorbidities were more likely to present with chemosensory dysfunction in comparison with females. SNOT-22 questionnaire revealed that nasal blockage and runny nose were more prevalent in mild/moderate, than in the severe, state of COVID-19. CONCLUSION: Our data confirm the commonality of chemosensory dysfunction during COVID-19 progression, and the significantly more pronounced combined dysfunction in males with severe COVID-19, and comorbidities.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) viral positivity and their burden in saliva of asymptomatic carriers - a systematic review and meta-analysis.

AIMS: The coronavirus disease 2019 (COVID-19) due to the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) can present either as an asymptomatic carrier state or an acute respiratory disease, with or without severe pneumonia. The asymptomatic carriers are a challenge for the dental profession as the infection could be transmitted via virus-laden, and saliva in dental settings through aerosol-generating procedures (AGPSs). The aim of this review was to perform a systematic review of SARS-CoV-2 in the saliva of asymptomatic individuals. MATERIALS AND METHODS: PubMed, Google scholar, and MedRxiv databases were searched between and a systematic review and meta-analysis of the available data were performed to assess the viral burden in the saliva of asymptomatic carriers of SARS-CoV-2. All investigators of the included studies used qRT-PCR to detect SARS-CoV-2 and yield quantitative data (the Ct values) appertaining to the viral load. RESULTS: A total of 322 records in the English literature were identified, and eight studies with 2642 SARS-CoV-2-positive and asymptomatic individuals were included in the final analysis. Of these, 16.7% (95% CI: 11-23%) yielded SARS-CoV-2-positive saliva samples in comparison to 13.1% (95% CI: 12-17%) of the respiratory specimens (nasopharyngeal or nose-throat swabs). CONCLUSION: As approximately 1 in 5 to 1 in 10 asymptomatic individuals harbour SARS-CoV-2 in either saliva or respiratory secretions, our results highlight the need for continued vigilance and the critical importance of maintaining strict, additional infection control regimens for the foreseeable future to mitigate the potential risks of COVID-19 transmission in dentistry.

The efficacy of bio-aerosol reducing procedures used in dentistry: a systematic review.

BACKGROUND AND OBJECTIVE: Bio-aerosols, are routinely generated and airborne in clinical dentistry due to the operative instrumentation within an oral environment bathed in salivary organisms. SARS-CoV-2 transmission being responsible for the current pandemic, appears through airborne aerosols and droplets, thus, there has been an intense focus on such aerosol-generating procedures, and their reduction. Hence the objective of this systematic review was to evaluate available data on three major measures: rubber dam application, pre-procedural oral rinse, and high-volume evacuators (HVE) aimed at reducing bio-aerosols. METHOD: PubMed via Ovid MEDLINE, EBSCO host, Cochrane Library and Web of Science databases were searched between 01 January 1985 and 30 April 2020. RESULTS: A total of 156 records in English literature were identified, and 17 clinical studies with 724 patients included in the final analysis. Eligible articles revealed the inadequacy of three principle approaches used in contemporary dental practice to minimize such bio-aerosols, rubber dam application, pre-procedural oral rinses, and HVE. The latter is an extremely effective method to reduce bio-aerosols in dentistry, although no single method can provide blanket cover. CONCLUSION: Present systematic review indicates that employing combination strategies of rubber dam, with a pre-procedural antimicrobial oral rinse, and HVE may contain bio-aerosols during operative procedures.

The effectiveness and efficacy of respiratory protective equipment (RPE) in dentistry and other health care settings: a systematic review.

OBJECTIVE: The global pandemic of coronavirus disease-19, caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), is the latest hazard facing healthcare workers (HCW) including dental care workers (DCW). It is clear that the major mode of SARS-CoV-2 transmission is the airborne route, through inhalation of virus-infested aerosols and droplets. Several respiratory protection equipment (RPE), including masks, face shields/visors, and respirators, are available to obviate facial and conjunctival contamination by microbes. However, as their barrier value against microbial inhalation has not been evaluated, we systematically reviewed the data on the effectiveness and efficacy of facemasks and respirators, including protective eyewear, with particular emphasis on dental healthcare. MATERIAL AND METHODS: PubMed, MEDLINE, the Cochrane Library, and Embase databases were searched between 01January 1990 and 15 May 2020. RESULTS: Of 310 identified English language records, 21 were included as per eligibility criteria. In clinical terms, wearing layered, face-fitting masks/respirators and protective-eyewear can limit the spread of infection among HCWs. Specifically, combined interventions such as a face mask and a face shield, better resist bioaerosol inhalation than either alone. The prolonged and over-extended use of surgical masks compromise their effectiveness. CONCLUSIONS: In general, RPE is effective as a barrier protection against aerosolized microbes in healthcare settings. But their filtration efficacy is compromised by the (i) inhalant particle size, (ii) airflow dynamics, (iii) mask-fit factor, (iv) period of wear, (v) 'wetness' of the masks, and (vi) their fabrication quality. The macro-data presented here should inform policy formulation on RPE wear amongst HCWs.

Sudden onset, acute loss of taste and smell in coronavirus disease 2019 (COVID-19): a systematic review.

BACKGROUND: Early detection, isolation and management of COVID-19 are crucial to contain the current pandemic. US Centers for Disease Control and Prevention (CDC) recently included 'sudden loss of taste (dysgeusia/ageusia) and smell (anosmia/hyposmia)' as symptoms of COVID-19. If indeed these symptoms are reliable and specific forerunner symptoms of COVID-19, then it may facilitate detection and containment of the disease. Hence, we systematically evaluated the contemporary evidence on dysgeusia and anosmia as trigger prodromal symptoms, and their prevalence in COVID-19 patients. METHODS: Ovid MEDLINE, EBSCO host and Web of Science databases were searched between 25 December 2019 and 30 May 2020. RESULTS: Of the 13 identified records, eight studies, totalling 11,054 COVID-19 patients, were included, as per the selection criteria. Eligible articles reflected research conducted mostly in the European community, as well as China, the US and Iran. In total, anosmia and dysgeusia symptoms were present in 74.9% and 81.3% ambulatory as well as hospitalized, mild-to-severe cases of COVID-19 patients, respectively. The European, US and Iran data indicate olfactory and gustatory symptoms appear prior to general COVID-19 symptoms in 64.5% and 54.0% of the patients, respectively. CONCLUSIONS: To our knowledge, this is the first systematic review analysing the meager data based on the prevalence of chemosensory dysfunction in COVID-19. Critical analysis of such macro-data, as and when available, is essential to evaluate their utility as harbingers of COVID-19 onset, and to establish clinical practice guidelines both in dentistry and medicine.

Clinical efficacy and the antimicrobial potential of silver formulations in arresting dental caries: a systematic review.

BACKGROUND: The use of silver-formulation as microbicide to arrest dentinal caries is gaining popularity. The primary objective of the present appraisal was to systematically review the clinical (in vivo) applications and antimicrobial potential of silver-containing formulations in arresting dentinal caries. Our secondary aim was to sum up the available in vitro applications of silver-containing formulations against cariogenic microbes isolated from dentine lesions. METHODS: Ovid MEDLINE, EBSCO host, Web of Science, and Cochrane Library databases was searched between January 2009-May 2019. RESULTS: In vivo: We observed conflicting evidence of antimicrobial efficacy of SDF on a diverse array of microbial taxa present in carious dentine of primary and permanent teeth. Moreover, there is insufficient evidence on the application of AgNP-fluoride as an effective microbicidal against cariogens of dentine lesions. In vitro: We found a good evidence of microbicidal efficacy of silver diamine fluoride (SDF) on selective cariogenic microbes in human dentine model. Additionally, a good evidence was noted of in vitro application of silver nanoparticles (AgNPs) as a useful microbicidal against S. mutans adhesion, growth and subsequent biofilm formation in human dentine models. CONCLUSIONS: Taken together, in vitro evidence indicates the promising antimicrobial potential of silver-based formulations (SDF and nanosilver) against the predominant cariogenic flora, particularly from dentine lesions. Post-treatment clinical data of either the bactericidal and bacteriostatic effects of SDF or nanosilver are sparse. Furthermore, the current understanding of the specific size, concentration, antimicrobial mechanisms, and toxicological aspects of nano-silver compounds is inadequate to draw firm conclusions on their clinical utility.

Silver diamine fluoride (SDF) used in childhood caries management has potent antifungal activity against oral Candida species.

BACKGROUND: The microbiome of Severe-Early Childhood Caries (S-ECC), is characterized by an ecosystem comprising bacterial and fungal species, with a predominance of Candida species. Hence, an anti-cariogen effective against both bacteria and fungi would be valuable in the management of S-ECC. Here we evaluate the antifungal effect of silver diamine fluoride (SDF) against 35-clinical yeast isolates (Ten-each of C. albicans, C. krusei, C. tropicalis and five C. glabrata strains) from dentinal caries-lesions from S-ECC. RESULTS: Disc-diffusion and time-kill assays as well as MIC50 and MIC90 evaluations against therapeutic concentrations confirmed the broad-spectrum anti-candidal potency of SDF. Ultrastructural images revealed morphologic aberrations of yeast-cell walls on exposure to SDF. All C. krusei and C. glabrata isolates were significantly more sensitive to SDF, relative to the standard antifungal fluconazole. Further, SDF appears to effectively abrogate filamentation of C. albicans even at very low concentrations. CONCLUSIONS: Our data, for the first time, elucidate the antifungal potency of SDF, in addition to its known antibacterial activity, in the management of S-ECC.

Candida biome of severe early childhood caries (S-ECC) and its cariogenic virulence traits.

The protected niche of deep-caries lesions is a distinctive ecosystem. We assessed the Candida biome and its cariogenic traits from dentin samples of 50 children with severe-early childhood caries (S-ECC). Asymptomatic, primary molars belonging to International Caries Detection and Assessment-ICDAS caries-code 5 and 6 were analyzed, and C. albicans (10-isolates), C. tropicalis (10), C. krusei (10), and C. glabrata (5) isolated from the lesions were then evaluated for their biofilm formation, acidogenicity, and the production of secreted hydrolases: hemolysins, phospholipase, proteinase and DNase. Candida were isolated from 14/43 ICDAS-5 lesions (32.5%) and 44/57 ICDAS-6 lesions (77.2%). Compared to, ICDAS-5, a significantly higher frequency of multi-species infestation was observed in ICDAS-6 lesions (p=0.001). All four candidal species (above) showed prolific biofilm growth, and an equal potency for tooth demineralization. A significant interspecies difference in the mean phospholipase, as well as proteinase activity was noted (p < 0.05), with C. albicans being the predominant hydrolase producer. Further, a positive correlation between phospholipase and proteinase activity of Candida-isolates was noted (r = 0.818, p < 0.001). Our data suggest that candidal mycobiota with their potent cariogenic traits may significantly contribute to the development and progression of S-ECC.

Biodiversity of the human oral mycobiome in health and disease.

The organisms that colonize the human body over a lifetime are diverse, extensive and gargantuan. A fair proportion of the microbiota that constitutes this human microbiome live within our oral cavities mostly as harmonious associates causing only sporadic disease. An important core constituent of the microbiome is the mycobiome, representing various fungal genera. Up until recently, only a few species of fungi, mainly Candida species, were thought to constitute the human oral mycobiome. The reasons for this are manifold, although the uncultivable nature of many fungi in conventional laboratory media, and their complex genetic composition seem to be the major factors which eluded their detection over the years. Nevertheless, recent advances in computing and high-throughput sequencing such as next-generation sequencing (NGS) platforms have provided us a panoramic view of a totally new world of fungi that are human oral cohabitués. Their diversity is perplexing, and functionality yet to be deciphered. Here, we provide a glimpse of what is currently known of the oral mycobiome, in health and disease, with some future perspectives.