Oro-facial mucocutaneous manifestations of Coronavirus Disease-2019 (COVID-19): A systematic review.

We reviewed the prevalence, the likely aetiopathogenesis, and the management of oro-facial mucocutaneous manifestations of Coronavirus Disease-2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome Coronavirus -2 (SARS-CoV-2). English language manuscripts searched using standard databases yielded 26 articles that met the inclusion criteria. In total, 169 cases (75 females; 94 males) from 15 countries with a spectrum of COVID-19 severities were reviewed. Gustatory perturbations were prevalent in over 70%. Mucocutaneous manifestations were reported predominantly on the tongue, palate, buccal mucosa, gingivae, and lips and included ulcers, blisters, erosions, papillary hyperplasia, macules, glossitis, and mucositis. Ulcerative lesions, present in over 50 percent, were the most common oral manifestation. Lesions resembling candidal infections, with burning mouth, were prevalent in 19%. Petechiae and angina bullosa were generally seen, subsequent to COVID-19 therapies, in 11%. Ulcerated, necrotic gingivae were documented in severely ill with poor oral hygiene. These manifestations, present across the COVID-19 disease spectrum, were commonly associated with the immunosuppressed state and/ or the concurrent antimicrobial/steroidal therapies. In summary, a wide variety of orofacial mucocutaneous lesions manifest in COVID-19. They are likely to be secondary to the disease-associated immune impairment and/or pharmaco-therapy rather than a direct result of SARS-CoV-2 infection per se.

Diversity of site-specific microbes of occlusal and proximal lesions in severe- early childhood caries (S-ECC).

BACKGROUND: Severe-early childhood caries (S-ECC) a global problem of significant concern, commonly manifest on the occlusal, and proximal surfaces of affected teeth. Despite the major ecological differences between these two niches the compositional differences, if any, in the microbiota of such lesions is unknown. METHODS: Deep-dentine caries samples from asymptomatic primary molars of children with S-ECC (n 19) belonging to caries-code 5/6, (ICDAS classification) were evaluated. Employing two primer pools, we amplified and compared the bacterial 16S rRNA gene sequences of the seven hypervariable regions (V2-V4 and V6-V9) using NGS-based assay. RESULTS: Bray-Curtisevaluation indicated that occlusal lesions (OL) had a more homogeneous community than the proximal lesions (PL) with significant compositional differences at the species level (p = 0.01; R- 0.513). Together, the occlusal and proximal niches harbored 263 species, of which 202 (76.8%) species were common to both , while 49 (18.6%) and 12 (4.6%) disparate species were exclusively isolated from the proximal and occlusal niches, respectively. The most commonl genera at both niches included Streptococcus, Prevotella, and Lactobacillus. S. mutans was predominant in PL (p ≤ 0.05), and Atopobium parvulum (p = 0.01) was predominant in OL. CONCLUSIONS: Distinct differences exist between the caries microbiota of occlusal and proximal caries in S-ECC.

Coronavirus disease 2019 (COVID-19) vaccines: A concise review.

The development of a successful vaccine against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the agent of coronavirus disease 2019 (COVID-19), in an unmatched period of ten months, is a tribute to human ingenuity in the face of a vicious pandemic. A return to pre-pandemic "normalcy" depends on the successful delivery of the vaccine to a majority (~70%) so as to develop herd immunity critical to arrest the community spread of infection. Vaccination against COVID-19 is particularly important for dentistry as the dental team works in an environment replete with aerosol-generating procedures (AGP) that facilitate virus spread. Hence, a COVID-19 vaccine is likely to be an obligatory requirement for the dental practice, and the latest addition to the extensive list of vaccines required for dental professionals for the safe delivery of dental care. Here, we review the currently available major candidate vaccines against SARS-CoV-2 and their benefits and risks. These include the vaccines developed on next-generation platforms (mRNA, DNA, and viral vector vaccines), and the classic platforms (the live-attenuated virus, and the protein subunit vaccines) The review concludes with a summary of impending issues and challenges facing the provision of COVID-19 vaccines for all stakeholders in dentistry.

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.

Fungal species in endodontic infections: A systematic review and meta-analysis.

Fungal infections are common on oral mucosae, but their role in other oral sites is ill defined. Over the last few decades, numerous studies have reported the presence of fungi, particularly Candida species in endodontic infections, albeit in relatively small numbers in comparison to its predominant anaerobic bacteriome. Here, we review the fungal biome of primary and secondary endodontic infections, with particular reference to the prevalence and behavior of Candida species. Meta-analysis of the available data from a total of 39 studies fitting the inclusion criteria, indicate the overall weighted mean prevalence (WMP) of fungal species in endodontic infections to be 9.11% (from a cumulative total of 2003 samples), with 9.0% in primary (n = 1341), and 9.3% in secondary infections (n = 662). Nevertheless, WMP for fungi in primary and secondary infections which were 6.3% and 7.5% for culture-based studies, increased to 12.5% and 16.0% in molecular studies, respectively. The most prevalent fungal species was Candida spp. The high heterogeneity in the reported fungal prevalence suggests the need for standardized sampling, and speciation methods. The advent of the new molecular biological analytical platforms, such as the next generation sequencing (NGS), and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF), that enables identification and quantitation of a broad spectrum of hitherto unknown organisms in endodontic infections should radically alter our understanding of the endodontic mycobiome in the future. Candida spp. appear to be co-pathogens with bacteria in approximately one in ten patients with endodontic infections. Hence, clinicians should comprehend the importance and the role of fungi in endodontic infections and be cognizant of the need to eradicate both bacteria and fungi for successful therapy.

The effect of the combined use of silver diamine fluoride and potassium iodide in disrupting the plaque biofilm microbiome and alleviating tooth discoloration: A systematic review.

Silver diamine fluoride (SDF) is used in minimally invasive dentistry for arresting dental caries. However, discoloration of teeth is a significant side effect that has limited the use of SDF. Hence, the application of potassium iodide (KI) following SDF has been proposed to ameliorate the staining. Although antimicrobial activity is one of the major mechanisms of the caries-arresting effect of SDF, the antimicrobial potency of SDF/KI combination is unclear. Thus, the primary objective of this systematic review was to appraise the studies on the antimicrobial efficacy of SDF/KI combination on cariogenic microbes. The secondary objective was to summarize the evidence on the potential of KI in reducing the discoloration associated with the application of SDF. Electronic databases of Medline via PubMed, Cochrane Library, Web of Science, and EBSCO host were searched for English language manuscripts from January 2005 to 15th November 2020. The reference lists of these manuscripts were manually searched for additional studies. Twelve studies were included in the final analysis, seven of which have investigated the antimicrobial efficacy of SDF/KI, and the rest have examined the anti-staining potential of KI. The exploratory findings from the reviewed articles revealed the promising antimicrobial potential of SDF/KI on cariogenic microbes associated with dentine caries. There is, however, contradictory evidence on the effect of SDF/KI on tooth color. The reviewed in-vitro studies indicated significant effectiveness of KI in preventing staining. A clinical trial on primary dentition showed 25% reduction in the incidence of staining by SDF after applying KI, while a clinical study on root caries in adults showed no significant effect. Within the methodological limitations of this review, we conclude that for arresting dental caries, SDF could be combined with KI, as there may be a lower likelihood of staining. Further, well-designed clinical trials on the antimicrobial and anti-staining effect of SDF/KI are needed to obtain more robust evidence.

Facial protection in the era of COVID-19: A narrative review.

We live in extraordinary times, where COVID-19 pandemic has brought the whole world to a screeching halt. Tensions and contradictions that surround the pandemic ridden world include the availability, and the lack thereof, various facial protection measures to mitigate the viral spread. Here, we comprehensively explore the different types of facial protection measures, including masks, needed both for the public and the healthcare workers (HCW). We discuss the anatomy, the critical issues of disinfection and reusability of masks, the alternative equipment available for the protection of the facial region from airborne diseases, such as face shields and powered air-purifying respirators (PAPR), and the skin health impact of prolonged wearing of facial protection by HCW. Clearly, facial protection, either in the form of masks or alternates, appears to have mitigated the pandemic as seen from the minimal COVID-19 spread in countries where public mask wearing is strictly enforced. On the contrary, the healthcare systems, that appear to have been unprepared for emergencies of this nature, should be appropriately geared to handle the imbalance of supply and demand of personal protective equipment including face masks. These are two crucial lessons we can learn from this tragic experience.

Overview of transnational recommendations for COVID-19 transmission control in dental care settings.

On 11 March 2020, the World Health Organization (WHO) declared the coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2) as a pandemic. Until an effective treatment or a vaccine is developed, the current recommendations are to contain the disease, and control its transmission. It is now clear that the primary mode of SARS-CoV-2 transmission is aerosol/droplet spread, and by contacting virus-contaminated surfaces acting as fomites (inanimate vectors). Furthermore, recent data indicate that the live virus particles are present in saliva, and, more alarmingly, asymptomatic individuals may transmit the infection. By virtue of the nature of the practice of dentistry where intrinsically, a high volume of aerosols is produced, as well as the close proximity of dentists and patients during treatment, dentists and allied health staff are considered the highest risk health professional group for acquiring SARS-CoV-2 during patient management. Therefore, several organizations and specialty associations have proposed guidelines and recommendations for limiting the transmission of SARS-COV-2 from carriers to dentists and vice versa. This paper aims to provide a review of these guidelines, and concludes with a brief look at how the practice of dentistry may be impacted by COVID-19, in the post-pandemic era.

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.

Antibiotic prescribing practices of dentists for endodontic infections; a cross-sectional study.

OBJECTIVE: The indiscriminate prescription of antibiotics has led to the emergence of resistance microbes worldwide. This study aimed to investigate the antibiotic prescribing practices amongst general dental practitioners and specialists in managing endodontic infections in the United Arab Emirates (UAE). DESIGN: General dental practitioners and specialists in the UAE were invited to participate in an online questionnaire survey which included questions on socio-demographics, practitioner's antibiotic prescribing preferences for various pulpal and periapical diseases, and their choice, in terms of the type, dose and duration of the antibiotic. The link to the survey questionnaire was sent to 250 invited dentists. Data were analyzed by descriptive statistics and chi-square tests for independence and level of significance was set at 0.05. RESULTS: A total of 174 respondents participated in the survey (response rate = 70%). The respondents who prescribed antibiotics at least once a month were 38.5% while 17.2% did so, more than three times a week; amoxicillin 500 mg was the antibiotic of choice for patients not allergic to penicillin (43.7%), and in cases of penicillin allergies, erythromycin 500 mg (21.3%). There was a significant difference in the antibiotic prescribing practices of GDPs compared to endodontists and other specialties especially in clinical cases such as acute apical abscesses with swelling and moderate to severe pre-operative symptoms and retreatment of endodontic cases (p<0.05). Approximately, three quarters of the respondents (78.7%) did not prescribe a loading dose when prescribing antibiotics. About 15% respondents prescribed antibiotics to their patients if they were not accessible to patients due to a holiday/weekend. CONCLUSIONS: In general, the antibiotic prescribing practices of UAE dentists are congruent with the international norms. However, there were occasions of inappropriate prescriptions such as in patients with irreversible pulpitis, necrotic pulps with no systemic involvement and/or with sinus tracts.

Prevalence, virulence and antifungal activity of C. albicans isolated from infected root canals.

BACKGROUND: There is limited data on the prevalence of Candida species in infected root canal systems of human teeth. We attempted to investigate the prevalence, genotype, virulence and the antifungal susceptibility of Candida albicans isolated from infected root canals of patients with primary and post-treatment infections in a UAE population. METHODS: Microbiological samples from 71 subjects with infected root canals were aseptically collected, and cultured on Sabouraud dextrose agar, and C. albicans was identified using multiplex polymerase chain reaction, and the isolates were further subtyped using ABC genotyping system. Their relative virulence was compared using further four archival samples of endodontic origin from another geographical region, and four more salivary isolates, as controls. The virulence attributes compared were biofilm formation, and production of phospholipase and haemolysin, and the susceptibility to nystatin, amphotericin B, ketoconazole, and fluoconazole was also tested. RESULTS: 4 out of 71 samples (5.6%) yielded Candida species. On analysis of variance among the groups, the intracanal isolates, mainly Genotype A, possessed a high degree of phospholipase and haemolysin activity (p < 0.05). The UAE and Finland isolates were stronger biofilm formers and had superior phospholipase production capacity compared with the salivary isolates. All isolates were sensitive to the antifungal chemicals used. The salivary isolates were more sensitive to fluoconazole compared to other groups (p < 0.05). CONCLUSION: The prevalence of C. albicans in infected root canals of patients attending a dental hospital in UAE is low. The strains isolated were good biofilm formers, possessed strong phospholipase and haemolysin activity and were mostly of the genotype A. The fact that the root canal isolates possessed significant hydrolase activity, imply that they are equipped with virulence attributes necessary for survival within a harsh intracanal ecosystem.

The antibacterial efficacy of silver diamine fluoride (SDF) is not modulated by potassium iodide (KI) supplements: A study on in-situ plaque biofilms using viability real-time PCR with propidium monoazide.

Silver diamine fluoride (SDF) is commonly used to arrest caries lesions, especially in early childhood caries. Recently, it was suggested that SDF can be combined with potassium iodide (KI) to minimize the discoloration of demineralized dentine associated with SDF application. However, the antibacterial efficacy of SDF alone or combined with KI on in-situ biofilm is unknown. Hence, we compared the anti-plaque biofilm efficacy of two different commercially available SDF solutions, with or without KI, using an in-situ biofilm, analysed using viability real-time PCR with propidium monoazide (PMA). Appliance-borne in-situ biofilm samples (n = 90) were grown for a period of 6 h in five healthy subjects who repeated the experiment on three separate occasions, using a validated, novel, intraoral device. The relative anti-biofilm efficacy of two SDF formulations; 38.0% Topamine (SDFT) and 31.3%, Riva Star (SDFR), KI alone, and KI in combination with SDFR (SDFR+KI) was compared. The experiments were performed by applying an optimized volume of the agents onto the biofilm for 1min, mimicking the standard clinical procedure. Afterwards the viability of the residual biofilm bacteria was quantified using viability real-time PCR with PMA, then the percentage of viable from total bacteria was calculated. Both SDF formulations (SDFT and SDFR) exhibited potent antibacterial activities against the in-situ biofilm; however, there was non-significant difference in their efficacy. KI alone did not demonstrate any antibacterial effect, and there was non-significant difference in the antibacterial efficacy of SDF alone compared to SDF with KI, (SDFT v SDFR/KI). Thus, we conclude that the antibacterial efficacy of SDF against plaque biofilms is not modulated by KI supplements. Viability real-time PCR with PMA was successfully used to analyze the viability of naturally grown oral biofilm; thus, the same method can be used to test the antimicrobial effect of other agents on oral biofilms in future research.

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.

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.

Cariogenic microbiome and microbiota of the early primary dentition: A contemporary overview.

Recent advances in the field of molecular microbiology provide an unprecedented opportunity to decipher the vast diversity of the oral microbiome in health and disease. Here, we provide a contemporary overview of the oral microbiome and the microbiota of early childhood caries (ECC) with particular reference to newer analytical techniques. A MEDLINE search revealed a total of 20 metagenomic studies describing cariogenic microbiomes of ECC, 10 of which also detailed the healthy microbiomes. In addition, seven studies on site-specific microbiomes, focusing on acidogenic and aciduric microbiota of deep-dentinal lesions, were also reviewed. These studies evaluated plaque and saliva of children aged 1.5-11 years, in cohorts of 12-485 individuals. These studies reveal a very rich and diverse microbial communities, with hundreds of different phylotypes and microbial species, including novel species and phyla such as Scardovia wiggsiae, Slackia exigua, Granulicatella elegans, Firmicutes in the plaque biofilms of children with ECC. On the contrary, bacteria such as Streptococcus cristatus, S. gordonii, S. sanguinis, Corynebacterium matruchotii, and Neisseria flavescens were common in plaque biofilm of noncarious, healthy, tooth surfaces in subjects with caries. The review illustrates the immense complexity and the diversity of the human oral microbiota of the cariogenic plaque microbiome in ECC, and the daunting prospect of its demystification.

Candida albicans orf19.3727 encodes phytase activity and is essential for human tissue damage.

Candida albicans is a clinically important human fungal pathogen. We previously identified the presence of cell-associated phytase activity in C. albicans. Here, we reveal for the first time, that orf19.3727 contributes to phytase activity in C. albicans and ultimately to its virulence potency. Compared with its wild type counterpart, disruption of C. albicans orf19.3727 led to decreased phytase activity, reduced ability to form hyphae, attenuated in vitro adhesion, and reduced ability to penetrate human epithelium, which are the major virulence attributes of this yeast. Thus, orf19.3727 of C. albicans plays a key role in fungal pathogenesis. Further, our data uncover a putative novel strategy for anti-Candidal drug design through inhibition of phytase activity of this common pathogen.