Association between periodontitis and severity of COVID-19 infection: A case-control study

Role of viruses in periodontitis: An extensive review of herpesviruses, human immunodeficiency virus, coronavirus-19, papillomavirus and hepatitis viruses

Periodontitis is the inflammation of the supporting structures around the dentition. Several microbial agents, mostly bacteria, have been identified as causative factors for periodontal disease. On the other hand, oral cavity is a rich reservoir for viruses since it contains a wide variety of cell types that can be targeted by viruses. Traditionally, the focus of research about the oral flora has been on bacteria because the most widespread oral diseases, like periodontitis and dental caries, are outcomes of bacterial infection. However, recently and especially after the emergence of coronavirus disease 2019, there is a growing tendency toward including viruses also into the scope of oral microbiome investigations. The global high prevalence of periodontitis and viral infections may point out to a concomitant or synergistic effect between the two. Although the exact nature of the mechanism still is not clearly understood, this could be speculated through the manipulation of the immune system by viruses; hence facilitating the furthermore colonization of the oral tissues by bacteria. This review provides an extensive and detailed update on the role of the most common viruses including herpes family (herpes simplex, varicella-zoster, Epstein-Barr, cytomegalovirus), Human papillomaviruses, Human immunodeficiency virus and severe acute respiratory syndrome coronavirus 2 in the initiation, progression and prognosis of periodontitis.

Association of self-reported periodontal disease and inequities with long haul COVID-19

In 2000, the Surgeon General's report highlighted that the mouth is a mirror for overall health of an individual and that disparities in oral health are directly proportionate to general health inequities. Among patients hospitalized due to COVID-19, diabetes and cardiovascular disease are the most common comorbidities; several studies support the association of these conditions with periodontal disease. This study's main aim is to assess the disproportionate impact of the COVID-19 pandemic on populations from lower socioeconomic statuses. The study also aims to assess the association of self-reported periodontal disease with COVID-19 disease course and severity. A sample population of Indiana residents with positive diagnosis of SARS-CoV-2 were recruited. A validated survey tool was sent to this cohort inquiring about sociodemographic distribution; co-morbid conditions, current symptoms of "long haul COVID," course of their COVID-19 infection; history of periodontal disease, existing periodontal disease symptoms, and oral hygiene habits. 209 individuals with a history of positive COVID test were returned to the survey, and association of participant characteristics and periodontal disease-related survey items with COVID-related survey items were evaluated using chi-square tests. Lower sense of smell ratings was associated with less education (p = 0.021), being unemployed/disabled (p = 0.008), worse health status (p<0.001), more frequent bleeding gums (p = 0.031), more frequent toothache (p<0.001), lower oral health rating (p = 0.002), and vaccine status (p = 0.011). Lower sense of taste ratings were associated with older age (p = 0.018), worse health (p<0.001), more frequent bleeding gums (p<0.001), more frequent mobile or loose tooth (p = 0.010), presence of gum disease (p<0.001), more frequent loss of teeth (p = 0.013), more frequent toothache (p<0.001), worse oral health (p = 0.001), teeth lost due to gum disease (p = 0.006), and vaccine status (p = 0.001). History of hospitalization due to COVID-19 was found to be associated with a history of gum disease within the past 12 months.

Inhibition of SARS-CoV-2 infection by Porphyromonas gingivalis and the oral microbiome

The COVID-19 pandemic persists despite the availability of vaccines, and it is, therefore, crucial to develop new therapeutic and preventive approaches. In this study, we investigated the potential role of oral microbiome in SARS-CoV-2 infection. Using an in vitro SARS-CoV-2 pseudovirus infection assay, we found a potent inhibitory effect exerted by Porphyromonas gingivalis on SARS-CoV-2 infection mediated by known P. gingivalis compounds such as phosphoglycerol dihydroceramide (PGDHC) and gingipains as well as by unknown bacterial factors. We found that the gingipain-mediated inhibition of infection is likely due to cytotoxicity, whereas PGDHC inhibited virus infection by an unknown mechanism. Unidentified factors present in P. gingivalis supernatant inhibited SARS-CoV-2 likely via the fusion step of the virus life cycle. We addressed the role of other oral bacteria and found certain periodontal pathogens capable of inhibiting SARS-CoV-2 pseudovirus infection by inducing cytotoxicity on target cells. In the human oral cavity, we observed that the modulatory activity of oral microbial communities varied among individuals, in that some saliva-based cultures were capable of inhibiting while others were enhancing infection. These findings contribute to our understanding of the complex relationship between the oral microbiome and viral infections, offering potential avenues for innovative therapeutic strategies in combating COVID-19.

IMPORTANCE

The oral microbiome is important in health and disease, and in this study, we addressed the potential role of the oral microbiome in COVID-19 infection. Our in vitro studies suggest that certain bacteria of the oral microbiome such as P. gingivalis produce compounds that could potentially inhibit SARS-CoV-2 infection. These findings elucidating the interactions between the oral microbiome and SARS-CoV-2 infection will be important in our understanding of COVID-19 pathogenesis and the development of innovative therapeutic and preventive strategies against COVID-19 infection.

Exploring the correlation between periodontal disease and serum biomarkers in haemodialysis patients

BACKGROUND

Patients undergoing haemodialysis are more susceptible to infectious diseases, including periodontitis. This study aimed to investigate the Correlation between periodontal disease and serum markers in Yemeni haemodialysis patients.

METHODS

A cross-sectional study was conducted on a sample of 70 haemodialysis patients. Patient interviews, clinical examinations, and laboratory tests were performed to collect data. Serum levels of albumin, calcium, phosphorus, haemoglobin, ferritin, and creatinine were measured, with separate measurements for cystatin C The association between categorical variables was assessed using the chi-square test and Pearson's correlation coefficient, considering a significance level of p < 0.05.

RESULTS

Significant correlations were found between serum biomarkers and periodontal clinical parameters. Phosphorus, creatinine, albumin, ferritin, and creatinine levels correlated significantly with the Plaque Index (p < 0.001, p < 0.001, p = 0.015, p = 0.018, and p = 0.03). While the Ferritin level showed significant correlations with both the Plaque Index and Miller Classes (r = 0.281, p = 0.018 and r = 0.258, p = 0.031), respectively. The Calcium level showed a significant correlation with the Gingival Index (r = 0.266, p = 0.027). Cystatin C level was statistically correlated with mobility (r = 0.258, p = 0.031). Also, the result showed a significant correlation between Creatinine levels and Periodontitis (r = 0.26, p = 0.03).

CONCLUSION

This study provides evidence of a strong association between periodontal disease and chronic kidney disease in Yemeni haemodialysis patients. The findings emphasize the significance of maintaining good oral health in the care of haemodialysis patients.

Can periodontitis affect the COVID-19 severity, symptoms, hospital stay, and mortality? A case-control study

Background/purpose

Poor oral hygiene and periodontal disease have been identified as potential risk factors for the coronavirus disease 2019 (COVID-19). The present study aimed to determine the association between periodontitis and COVID-19 severity, nature of symptoms, mortality, and hospital stay.

Methods

In total, 163 COVID-19-positive patients (men: 93; women: 70) were categorized into two groups: the control group, consisting of 120 patients with asymptomatic or mild symptoms, and the case group, consisting of 43 patients with moderate-to-severe symptoms. The severity of periodontal disease, oral hygiene status (OHI), pocket depth (PD), bleeding on probing (BOP), number of decayed/missing/filled teeth, mortality, duration of stay in the hospital, oxygen requirement, and nature of COVID-19 symptoms were assessed in both groups. The association between periodontitis and COVID-19 was analyzed with other confounding factors such as age, sex, comorbidities, oral hygiene, and smoking status.

Results

The presence of periodontitis increases the severity of COVID-19 by 3.7 times (p = 0.002). A statistically significant difference was noted for symptoms such as dizziness (p = 0.036), running nose/cold (p = 0.009), and headache (p = 0.005) in the presence of periodontitis. The risk estimate for death associated with periodontitis was 1.03. Additionally, the average duration of stay was longer for individuals with periodontitis than for those in the control group.

Conclusion

There is a positive association between periodontal disease and COVID-19. Periodontitis increases the severity of COVID-19 and alters the symptoms. Hence, periodontal disease management should be an integral part of managing patients with coronavirus infection.

Therapeutic delivery of CCL2 modulates immune response and restores host-microbe homeostasis

Many chronic inflammatory diseases are attributed to disturbances in host-microbe interactions, which drive immune-mediated tissue damage. Depending on the anatomic setting, a chronic inflammatory disease can exert unique local and systemic influences, which provide an exceptional opportunity for understanding disease mechanism and testing therapeutic interventions. The oral cavity is an easily accessible environment that allows for protective interventions aiming at modulating the immune response to control disease processes driven by a breakdown of host-microbe homeostasis. Periodontal disease (PD) is a prevalent condition in which quantitative and qualitative changes of the oral microbiota (dysbiosis) trigger nonresolving chronic inflammation, progressive bone loss, and ultimately tooth loss. Here, we demonstrate the therapeutic benefit of local sustained delivery of the myeloid-recruiting chemokine (C-C motif) ligand 2 (CCL2) in murine ligature-induced PD using clinically relevant models as a preventive, interventional, or reparative therapy. Local delivery of CCL2 into the periodontium inhibited bone loss and accelerated bone gain that could be ascribed to reduced osteoclasts numbers. CCL2 treatment up-regulated M2-macrophage and downregulated proinflammatory and pro-osteoclastic markers. Furthermore, single-cell ribonucleic acid (RNA) sequencing indicated that CCL2 therapy reversed disease-associated transcriptomic profiles of murine gingival macrophages via inhibiting the triggering receptor expressed on myeloid cells-1 (TREM-1) signaling in classically activated macrophages and inducing protein kinase A (PKA) signaling in infiltrating macrophages. Finally, 16S ribosomal ribonucleic acid (rRNA) sequencing showed mitigation of microbial dysbiosis in the periodontium that correlated with a reduction in microbial load in CCL2-treated mice. This study reveals a novel protective effect of CCL2 local delivery in PD as a model for chronic inflammatory diseases caused by a disturbance in host-microbe homeostasis.

Causal relationships of infection with Helicobacter pylori and herpesvirus on periodontitis: A Mendelian randomization study

Background

To explore the causal association between Helicobacter pylori (H. pylori) infection, herpesvirus infection and periodontitis (PD) from a genetic perspective using Mendelian randomization (MR).

Methods

The PD data were derived from genome-wide association study (GWAS) from the Dental Endpoints (GLIDE) consortium, and the FinnGen Biobank provided data on H. pylori and herpesvirus infections. In addition, we examined GWAS data for subtypes of H. pylori and herpesvirus infection. Inverse variance weighting (IVW) was selected as a major analysis technique, and weighted median (WM), weighted model, simple model, and MR-Egger regression were added as supplementary methods. To verify the findings, the effects of pleiotropy and heterogeneity were assessed.

Results

Genetically predicted H. pylori infection (OR = 0.914, 95%CI = 0.693-1.205, P = 0.523), anti-H. pylori VacA (OR = 0.973, 95%CI = 0.895-1.057, P = 0.515), anti-H. pylori CagA (OR = 1.072, 95%CI = 0.986-1.164; P = 0.102), Epstein-Barr virus (EBV) infection (OR = 1.026, 95%CI = 0.940-1.120, P = 0.567), Herpes simplex virus (HSV) infection (OR = 0.962, 95%CI = 0.883-1.048, P = 0.372), cytomegalovirus (CMV) infection (OR = 1.025, 95%CI = 0.967-1.088, P = 0.415), EBV nuclear antigen-1 (EBNA1) (OR = 1.061, 95%CI = 0.930-1.209, P = 0.378), EBV virus capsid antigen (VCA) (OR = 1.043, 95CI% = 0.890-1.222, P = 0.603), HSV-1 (OR = 1.251, 95%CI = 0.782-2.001, P = 0.351), HSV-2 (OR = 1.020, 95%CI = 0.950-1.096, P = 0.585), CMV IgG (OR = 0.990, 95CI% = 0.882-1.111, P = 0.861) were not associated with PD, indicated that H. pylori and herpesvirus infection had no causal relationship to PD. Reverse studies also found no cause effect of PD on H. pylori or herpesvirus infection. The results of the sensitivity analysis suggested the robustness of the MR results.

Conclusion

This study offered preliminary proof that H. pylori and herpesvirus infections were not causally linked to PD, and vice versa. However, more robust instrumental variables (IVs) and larger samples of GWAS data were necessary for further MR analysis.

Targeting the Neuropilin-1 receptor with Ovatodiolide and progress in using periodontal ligament organoids for COVID-19 research and therapy

The discovery of SARS-CoV-2 RNA in the periodontal tissues of patients who tested positive for COVID-19, 24 days post the initial symptom onset, indicates the oral cavity could serve as a viral reservoir. This research aims to investigate the antiviral capabilities of Ovatodiolide, introducing a novel periodontal ligament organoid model for the study of SARS-CoV-2. We have successfully established a reliable and expandable organoid culture from the human periodontal ligament, showcasing characteristics typical of epithelial stem cells. This organoid model enables us to delve into the lesser-known aspects of dental epithelial stem cell biology and their interactions with viruses and oral tissues. We conducted a series of in vitro and ex vivo studies to examine the inhibitory impacts of Ova on SARS-CoV-2. Our findings indicate that Ovatodiolide molecules can bind effectively to the NRP1 active domain. Our study identifies potential interaction sites for Ovatodiolide (OVA) within the b1 domain of the NRP1 receptor. We generated point mutations at this site, resulting in three variants: Y25A, T44A, and a double mutation Y25A/T44A. While these mutations did not alter the binding activity of the spike protein, they did impact the concentration of OVA required for inhibition. The inhibitory concentrations for these variants are 15 μM for Y25A, 15.2 μM for T44A, and 25 μM for the double mutant Y25A/T44A. In addition, in vitro inhibition experiments demonstrate that the EC50 of Ova against the main protease (Mpro) of the SARS-CoV-2 virus is 7.316 μM. Our in vitro studies and the use of the periodontal ligament organoid model highlight Ovatodiolide's potential as a small molecule therapeutic agent that impedes the virus's ability to bind to the Neuropilin-1 receptor on host cells. The research uncovers various pathways and biochemical strategies through which Ovatodiolide may function as an effective antiviral small molecule drug.

COVID-19 Severity in Patients With Apical Periodontitis: A Case Control Study

OBJECTIVES

Apical periodontitis (AP) has been associated with systemic inflammatory biomarkers that have also been associated with COVID-19 severity. This study was designed to test the hypothesis that the presence of apical periodontitis could be associated with increased risk of COVID-19 complications.

METHODS

A case control study (N = 949) was performed using the medical and dental records of patients diagnosed with COVID-19 in the State of Qatar between March 2020 and February 2021. Cases comprised COVID-19 patients (n = 63) who experienced complications (death, intensive care unit admissions, mechanical ventilation), and controls were COVID-19 patients (n = 886) who recovered without such complications. The presence of periapical apical periodontitis was assessed on the radiographic records taken prior to COVID-19 infection. Associations between apical periodontitis and COVID 19 complications were analysed using logistic regression models adjusted for demographic and medical factors. Blood biomarkers were assessed in both groups and compared using the Kruskal-Wallis test.

RESULTS

COVID-19 complications were found to be associated with the presence of apical periodontitis (adjusted odds ratio = 2.72; 95% CI, 1.30-5.68; P = .008). Blood analyses revealed that COVID-19 patients with apical periodontitis had higher levels of white blood cells and haemoglobin A1c than the patients without apical periodontitis.

CONCLUSIONS

The presence of apical periodontitis could be associated with increased risk of COVID-19 complications.

Sputum production and salivary microbiome in COVID-19 patients reveals oral-lung axis

SARS-CoV-2, a severe respiratory disease primarily targeting the lungs, was the leading cause of death worldwide during the pandemic. Understanding the interplay between the oral microbiome and inflammatory cytokines during acute infection is crucial for elucidating host immune responses. This study aimed to explore the relationship between the oral microbiome and cytokines in COVID-19 patients, particularly those with and without sputum production. Saliva and blood samples from 50 COVID-19 patients were subjected to 16S ribosomal RNA gene sequencing for oral microbiome analysis, and 65 saliva and serum cytokines were assessed using Luminex multiplex analysis. The Mann-Whitney test was used to compare cytokine levels between individuals with and without sputum production. Logistic regression machine learning models were employed to evaluate the predictive capability of oral microbiome, salivary, and blood biomarkers for sputum production. Significant differences were observed in the membership (Jaccard dissimilarity: p = 0.016) and abundance (PhILR dissimilarity: p = 0.048; metagenomeSeq) of salivary microbial communities between patients with and without sputum production. Seven bacterial genera, including Prevotella, Streptococcus, Actinomyces, Atopobium, Filifactor, Leptotrichia, and Selenomonas, were more prevalent in patients with sputum production (p<0.05, Fisher's exact test). Nine genera, including Prevotella, Megasphaera, Stomatobaculum, Selenomonas, Leptotrichia, Veillonella, Actinomyces, Atopobium, and Corynebacteria, were significantly more abundant in the sputum-producing group, while Lachnoanaerobaculum was more prevalent in the non-sputum-producing group (p<0.05, ANCOM-BC). Positive correlations were found between salivary IFN-gamma and Eotaxin2/CCL24 with sputum production, while negative correlations were noted with serum MCP3/CCL7, MIG/CXCL9, IL1 beta, and SCF (p<0.05, Mann-Whitney test). The machine learning model using only oral bacteria input outperformed the model that included all data: blood and saliva biomarkers, as well as clinical and demographic variables, in predicting sputum production in COVID-19 subjects. The performance metrics were as follows, comparing the model with only bacteria input versus the model with all input variables: precision (95% vs. 75%), recall (100% vs. 50%), F1-score (98% vs. 60%), and accuracy (82% vs. 66%).

Association between sequelae of COVID-19 with periodontal disease and obesity: A cross-sectional study

BACKGROUND

To assess the sequelae of coronavirus disease 2019 (COVID-19) and associated factors, such as obesity and periodontitis in adults.

METHODS

The study included 128 individuals aged ≥35 years with a history of a diagnosis of COVID-19 through real-time polymerase chain reaction (RT-PCR), from Pelotas, Brazil. Self-report sequelae from COVID-19 were defined as the primary outcome. A questionnaire containing sociodemographic, medical, behavioral and self-report of sequelae of COVID-19 was applied. A complete periodontal clinical examination was performed. Weight and height were assessed. Uni-, bi- and multivariate analyses were performed using Poisson regression with robust variance. Additional analyses were performed considering obesity as a subgroup.

RESULTS

When considering the whole sample, no statistically significant associations between sequelae of COVID-19 with periodontitis (prevalence ratio [PR]:1.14;95% confidence interval [95%CI]: 0.80-1.61) and obesity (0.93 [0.68-1.26]) were identified. In the subgroup analysis, considering only individuals with obesity, those diagnosed with generalized periodontitis had 86% higher probability to have sequelae of COVID-19 when compared to individuals with periodontal health or localized periodontitis. However, when only those without obesity were considered, no significant association with periodontal status was detected (0.82 [0.55-1.23). No significant association with periodontal status were observed when the severity of sequelae (no sequelae, 1 sequela, and >1 sequela) were considered (p > 0.05).

CONCLUSIONS

Individuals diagnosed with obesity and periodontitis have a higher PR of reporting sequelae from COVID-19 compared to individuals with only obesity.

Association between periodontal health and trait anxiety in Egyptian women: A cross-sectional study

OBJECTIVES

This study explored the relationship between periodontal problems and trait anxiety in a sample of Egyptian women.

MATERIALS AND METHODS

The Egyptian validated Arabic version of the State-Trait Anxiety Inventory-Trait subscale was used to measure levels of trait anxiety, and the periodontal health status of 451 Egyptian women was assessed using the Community Periodontal Index. Data were also collected on potential covariates such as age, educational level, marital status, parity, smoking, and oral healthcare-seeking behavior. Multivariate logistic regression analysis was done to evaluate the association between periodontal diseases and trait anxiety.

RESULTS

Among study participants, and after adjusting for some of the potential confounders, trait anxiety exhibited weak association with periodontal diseases (OR: 1.11; 95% CI= 1.07, 1.14; p <0.001). Also, old age (OR: 1.12; 95% CI = 1.07, 1.17; p < 0.001) as well as parity (OR: 7.26; 95% CI = 2.89, 18.27; p <0.001) were significantly associated with periodontal problems in the adjusted model.

CONCLUSION

While the study findings may implicate that personality traits, such as trait anxiety, could be linked to periodontal diseases more research is warranted to confirm or reject this association.

A prospective study on maternal periodontal diseases and neonatal adverse outcomes

OBJECTIVE

It is evident that periodontitis is linked to various adverse pregnancy outcomes. This prospective study explored the potential link of maternal periodontal diseases to neonatal adverse outcomes.

MATERIALS AND METHODS

A total of 193 generally healthy females in their third trimester (34-36 weeks) of pregnancy were enrolled. All subjects received full-mouth periodontal assessment, and the periodontal inflamed surface area (PISA) was calculated. Demographic data, lifestyles and anthropometric measurements of the neonates (e.g., body length and head circumference) were recorded. Herein, small-for-gestational age (SGA) referred to gender- and age-adjusted birth weight below the 10th percentile in line with the standard reference. Multivariable logistic regression analysis and restricted cubic spline were performed for examining the association of periodontal parameters with SGA.  Results: There were 8.3% (16/193) of neonates with SGA. Significantly positive correlation existed between the percentage of tooth sites with increased probing depth and an elevated risk of SGA (OR: 1.052; P < 0.05). Yet, the PISA was positively associated with the risk of SGA (OR: 1.002; P < 0.05) as well. No significant link occurred between maternal periodontal status and other neonatal outcome measures.

CONCLUSION

Within the limitations of this study, the findings suggest that there could be a link between maternal periodontal diseases and neonatal adverse outcomes like SGA. Further investigation is required to clarify the current findings and potential implications for promoting maternal oral/periodontal health and newborn health.

SARS-CoV-2, periodontal pathogens, and host factors: The trinity of oral post-acute sequelae of COVID-19

COVID-19 as a pan-epidemic is waning but there it is imperative to understand virus interaction with oral tissues and oral inflammatory diseases. We review periodontal disease (PD), a common inflammatory oral disease, as a driver of COVID-19 and oral post-acute-sequelae conditions (PASC). Oral PASC identifies with PD, loss of teeth, dysgeusia, xerostomia, sialolitis-sialolith, and mucositis. We contend that PD-associated oral microbial dysbiosis involving higher burden of periodontopathic bacteria provide an optimal microenvironment for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. These pathogens interact with oral epithelial cells activate molecular or biochemical pathways that promote viral adherence, entry, and persistence in the oral cavity. A repertoire of diverse molecules identifies this relationship including lipids, carbohydrates and enzymes. The S protein of SARS-CoV-2 binds to the ACE2 receptor and is activated by protease activity of host furin or TRMPSS2 that cleave S protein subunits to promote viral entry. However, PD pathogens provide additional enzymatic assistance mimicking furin and augment SARS-CoV-2 adherence by inducing viral entry receptors ACE2/TRMPSS, which are poorly expressed on oral epithelial cells. We discuss the mechanisms involving periodontopathogens and host factors that facilitate SARS-CoV-2 infection and immune resistance resulting in incomplete clearance and risk for 'long-haul' oral health issues characterising PASC. Finally, we suggest potential diagnostic markers and treatment avenues to mitigate oral PASC.

Proposed Mechanisms for the Relationship between Periodontal Diseases and the Severity of Covid-19: Common Pathogens, Inflammatory Mediators, and Risk Factors

Periodontal disease (PD) is a chronic inflammatory disease with some cytokine involvement, associated with several risk factors such as diabetes, obesity, etc., Corona Virus Disease 2019 (COVID-19), a new viral infection, also appears to be related to cytokine storm and similar risk factors. In this review, we intend to evaluate the possible relationship between PD and COVID-19. For data collection, English literature was searched in databases including PubMed and Google Scholar. The keywords searched were COVID-19, SARS-CoV-2, PD, respiratory Impact of Oral pathogens on respiratory diseases: Epidemiological studies indicated that oral pathogens are related to acute and chronic lung disease, and dental plaque is a likely reservoir for respiratory pathogens. Viral presence in the periodontal pocket: SARS-CoV-2 may be released from infected periodontal cells into periodontal pockets. Common inflammatory mediators: Several studies showed that the serum levels of interleukins (IL)-1, 6, 17, etc., increase in most patients with severe COVID-19. C-reactive protein (CRP) and endothelin 1(ET-1) may also be related to COVID-19 progression, and these mediators also increase in periodontitis. Common risk factors: Due to studies, diabetes mellitus (DM), obesity, aging, and male sex are the most important risk factors common between PDs and COVID-19 and may affect treatment outcomes and prognosis. PD seems to play a significant role in exacerbating COVID-19 and even affects the mortality rate of disease.

Identification of receptors and factors associated with human coronaviruses in the oral cavity using single-cell RNA sequencing

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) ravaged the world, and Coronavirus Disease 2019 (COVID-19) exhibited highly prevalent oral symptoms that had significantly impacted the lives of affected patients. However, the involvement of four human coronavirus (HCoVs), namely SARS-CoV-2, SARS-CoV, MERS-CoV, and HCoV-229E, in oral cavity infections remained poorly understood. We integrated single-cell RNA sequencing (scRNA-seq) data of seven human oral tissues through consistent normalization procedure, including minor salivary gland (MSG), parotid gland (PG), tongue, gingiva, buccal, periodontium and pulp. The Seurat, scDblFinder, Harmony, SingleR, Ucell and scCancer packages were comprehensively used for analysis. We identified specific cell clusters and generated expression profiles of SARS-CoV-2 and coronavirus-associated receptors and factors (SCARFs) in seven oral regions, providing direction for predicting the tropism of four HCoVs for oral tissues, as well as for dental clinical treatment. Based on our analysis, it appears that various SCARFs, including ACE2, ASGR1, KREMEN1, DPP4, ANPEP, CD209, CLEC4G/M, TMPRSS family proteins (including TMPRSS2, TMPRSS4, and TMPRSS11A), and FURIN, are expressed at low levels in the oral cavity. Conversely, BSG, CTSB, and CTSL exhibit enrichment in oral tissues. Our study also demonstrates widespread expression of restriction factors, particularly IFITM1-3 and LY6E, in oral cells. Additionally, some replication, assembly, and trafficking factors appear to exhibit broad oral tissues expression patterns. Overall, the oral cavity could potentially serve as a high-risk site for SARS-CoV-2 infection, while displaying a comparatively lower degree of susceptibility towards other HCoVs (including SARS-CoV, MERS-CoV and HCoV-229E). Specifically, MSG, tongue, and gingiva represent potential sites of vulnerability for four HCoVs infection, with the MSG exhibiting a particularly high susceptibility. However, the expression patterns of SCARFs in other oral sites demonstrate relatively intricate and may only be specifically associated with SARS-CoV-2 infection. Our study sheds light on the mechanisms of HCoVs infection in the oral cavity as well as gains insight into the characteristics and distribution of possible HCoVs target cells in oral tissues, providing potential therapeutic targets for HCoVs infection in the oral cavity.

Is There a Correlation Between Periodontal Disease Symptoms and the COVID-19 Vaccination?

OBJECTIVE

This study aimed to investigate and compare potential associations between different COVID-19 vaccines and periodontal diseases, mainly gingival bleeding and oral malodor (bad breath).

MATERIALS AND METHODS

This cross-sectional study used an online questionnaire consisting of 15 questions regarding demographic information, medical history, type of COVID-19 vaccine received, history of COVID-19, and general and periodontal symptoms after vaccination. The survey was voluntary and privately accessed online using SurveyMonkey®. A total of 2000 participants from three regions of Saudi Arabia participated in the study from October 11, 2021, to October 11, 2022.

RESULTS

Of the participants, 95.8% received at least one dose of the available COVID-19 vaccine. Oxford-AstraZeneca was the most administered (41.7%). Patients who suffered from chronic diseases or had a history of COVID-19 infection were less likely to be vaccinated (OR= 0.62, 95% CI 0.40-0.97; OR=0.62, 95% CI 0.39-0.99) compared with people with no chronic diseases or who had a history of COVID-19. The odds ratios for gingival bleeding, oral malodor, mobility, and tooth loss indicated no significant differences regarding vaccination status.

CONCLUSION

COVID-19 vaccines might not affect periodontal tissue conditions. People should not avoid vaccination due to concerns with oral or general health, as the benefits of vaccination outweigh the potential side effects.

Dental radiographic changes in individuals with COVID-19: a controlled retrospective study

OBJECTIVE

The aim of this study is to compare the pre-COVID-19 and post-COVID-19 dental radiological findings of individuals with positive rRT-PCR test results and with healthy controls using the apical periodontitis grade scale (APGS), radiographic-based periodontal bone loss (R-PBL), and radiographic DMFT indices, and to investigate the relatively long-term dental effects of COVID-19.

METHODS

This study included people who had two panoramic radiographs taken between 2018 and 2022. There are 52 patients with positive rRT-PCR tests in the study group. The control group included 50 individuals. Study and control groups were compared using the apical periodontitis grade scale (APGS), radiographic-based periodontal bone loss (R-PBL), and radiographic DMFT indices.

RESULTS

Although results showed a significant difference in percentage R-PBL value and R-PBL types in the study group, there was no significant difference in percentage R-PBL value and R-PBL types in the control group. Also, both groups showed a significant difference in the DMFT index.

CONCLUSIONS

According to the results of this study, it can be said that COVID-19 increases the incidence of periodontitis, and it can be interpreted that the pandemic may adversely affect the general oral health of all people.

YouTube as an information source for bleeding gums: A quantitative and qualitative analysis

Gum bleeding is a common dental problem, and numerous patients seek health-related information on this topic online. The YouTube website is a popular resource for people searching for medical information. To our knowledge, no recent study has evaluated content related to bleeding gums on YouTube™. Therefore, this study aimed to conduct a quantitative and qualitative analysis of YouTube videos related to bleeding gums. A search was performed on YouTube using the keyword "bleeding gums" from Google Trends. Of the first 200 results, 107 videos met the inclusion criteria. The descriptive statistics for the videos included the time since upload, the video length, and the number of likes, views, comments, subscribers, and viewing rates. The global quality score (GQS), usefulness score, and DISCERN were used to evaluate the video quality. Statistical analysis was performed using the Kruskal-Wallis test, Mann-Whitney test, and Spearman correlation analysis. The majority (n = 69, 64.48%) of the videos observed were uploaded by hospitals/clinics and dentists/specialists. The highest coverage was for symptoms (95.33%). Only 14.02% of the videos were classified as "good". The average video length of the videos rated as "good" was significantly longer than the other groups (p <0.05), and the average viewing rate of the videos rated as "poor" (63,943.68%) was substantially higher than the other groups (p <0.05). YouTube videos on bleeding gums were of moderate quality, but their content was incomplete and unreliable. Incorrect and inadequate content can significantly influence patients' attitudes and medical decisions. Effort needs to be expended by dental professionals, organizations, and the YouTube platform to ensure that YouTube can serve as a reliable source of information on bleeding gums.

Periodontitis links to concurrent metabolic disorders and abnormal liver function in pregnant women

OBJECTIVE

This cross-sectional study investigated the association of periodontitis with the metabolic status and hepatic function in pregnant women.

MATERIALS AND METHODS

Full-mouth periodontal conditions, metabolic profiles, and hepatic function were assessed in 219 self-reported healthy pregnant females. The association of periodontal status with the systemic parameters was evaluated by parametric and non-parametric tests, and multivariate logistic regression analysis.

RESULTS

Overall, periodontal status was positively associated with the metabolic profiles and hepatic function test results. The subjects with periodontitis exhibited higher levels of body mass index (BMI) (p < 0.01) and serum aspartate transaminase (AST) (p < 0.05), elevated diastolic blood pressure (DBP) (p < 0.05), and lower levels of high-density lipoprotein cholesterol (p < 0.05) than those of the counterparts. The periodontitis severity was strongly correlated with BMI and AST levels, and the extent of periodontal inflammation was related to DBP (p < 0.01). The periodontitis patients at 34-36 gestational weeks showed higher blood pressure and AST levels than those of non-periodontitis subjects (p < 0.05).

CONCLUSION

Our findings on the notable links of periodontitis to concurrent metabolic disorders and abnormal liver function in pregnant women highlight the need of proactive integration of regular periodontal screening and healthcare in maternal programs for promoting optimal health and wellbeing of mothers-to-be and newborns.

Inhibition of SARS-CoV-2 infection by Porphyromonas gingivalis and the oral microbiome

The COVID-19 pandemic persists despite the availability of vaccines, and it is therefore crucial to develop new therapeutic and preventive approaches. In this study, we investigated the potential role of the oral microbiome in SARS-CoV-2 infection. Using an in vitro SARS-CoV-2 pseudovirus infection assay, we found a potent inhibitory effect exerted by Porphyromonas gingivalis on SARS-CoV-2 infection mediated by known P. gingivalis compounds such as phosphoglycerol dihydroceramide (PGDHC) and gingipains as well as by unknown bacterial factors. We found that the gingipain-mediated inhibition of infection is likely due to cytotoxicity, while PGDHC inhibited virus infection by an unknown mechanism. Unidentified factors present in P. gingivalis supernatant inhibited SARS-CoV-2 likely via the fusion step of the virus life cycle. We addressed the role of other oral bacteria and found certain periodontal pathogens capable of inhibiting SARS-CoV-2 pseudovirus infection by inducing cytotoxicity on target cells. In the human oral cavity, we observed the modulatory activity of oral microbial communities varied among individuals in that some saliva-based cultures were capable of inhibiting while others were enhancing infection. These findings contribute to our understanding of the complex relationship between the oral microbiome and viral infections, offering potential avenues for innovative therapeutic strategies in combating COVID-19.

The role of viruses in oral mucosal lesions

The mucosa of the oral cavity is exposed to a large number of different microorganisms such as archaea, bacteria, fungi, parasites, and viruses. Among those, viruses cause specific infections, which can easily be transmitted from one person to another. The infectious route may not only include patients and their relatives but also the dental professional team. Thus, a wide knowledge regarding specific viral infections is crucial for the daily routine. Signs and symptoms of oral viral infections can be completely absent or develop into a pronounced clinical picture, so that early detection and information determine the further course of the infection and its influence on other inflammatory diseases, such as periodontitis, as well as the safety of family members and the social environment. As the clinical manifestation of viral infections may be highly variable leading to heterogenous mucosal lesions it is, in most cases, mandatory to differentiate them by specific microbiological tests in addition to clinical examination procedures. This article will give an overview of the role of viruses infecting the oral mucosa, and in addition, describe their clinical manifestation and management.

Changes in oral home care and smoking habits during COVID-19 pandemic: A cross-sectional study

OBJECTIVES

The coronavirus disease-19 (COVID-19) pandemic has caused disruption in the health behavior in many aspects of life. While hand hygiene was promoted as one of the precautionary measures to mitigate and contain COVID-19, oral health and smoking might have received less attention in the media campaigns. The aim of this study was to examine health behavioral changes in terms of oral home care habits, smoking, and perception of dental care during the COVID-19 pandemic.

MATERIAL AND METHODS

An online survey was designed to assess oral home care, smoking habits, and attitude toward dental services of participants aged 18 years and older. The data were collected between September and November 2021. The strength of association between changes in oral home care habits, smoking, and attitude toward invasive/long dental procedures and each variable was measured by χ2 analysis. Estimates of relative risk were also calculated for all variables. Predictors of avoiding dental procedures were estimated by a binary logistic regression.

RESULTS

A total of 532 participants, based in the United Arab Emirates, took part in this online survey with a response rate of 88.7%. The age of the participants ranged between 18 and 67 with mean age of 34.9 ± 9.0 years. The majority of the participants have adopted changes in their routine oral home care habits, with 82.1% of them changing the toothbrush more frequently. Participants who changed their oral home care habits were more likely to have received sufficient information on the importance of maintaining oral health. Likewise, the changes in smoking habits were significantly associated with receiving information on the relationship between smoking and the severity of the COVID-19 (p < 0.001).

CONCLUSIONS

The findings showed that positive behavior toward oral home care and smoking was noticed during the pandemic particularly when public receives sufficient and up-to-date information.

Bibliometric analysis and visualization of top papers in dentistry from 2012 to 2022 based on essential science indicators

OBJECTIVES

This study aims to analyze and visualize the top dental papers from 2012 to 2022 using data from essential science indicators (ESIs).

MATERIALS AND METHODS

The present study was conducted using library and retrospective bibliometric analysis methods. Additionally, a science map has been created. Web of Science was searched on January 18, 2023. The results were limited to the top papers in ESIs. The bibliometric information of the top papers was evaluated. Next, the VOSviewer was used to perform a co-occurrence analysis and visualize data.

RESULTS

The findings showed that Mariano Belén Sanz and Maurizio S. Tonetti were the top two authors. The University of London and the University of Bern had the highest number of articles. These articles were published in 55 journals. According to the analysis of keyword co-occurrence, the most frequently used keywords in the field of dentistry include "periodontitis," "dental implants," "periodontal disease," "mechanical properties," "peri-implantitis," "oral health," "dental caries," "dental materials," "3D printing."

CONCLUSION

The findings of this study enable readers to pinpoint the authors, organizations, countries, and journals that have made the biggest contributions to the list of the most often cited dentistry papers. In medicine, bibliometric citation analysis is frequently used to assist researchers in learning the fundamentals of a subject and pinpoint subtopics of broad interest for additional study.

Association between dysbiotic perio-pathogens and inflammatory initiators and mediators in COVID-19 patients with diabetes

It has been suggested that a corona virus infection is linked to chronic periodontitis (COVID-19). Our objectives were to look at the expression of angiotensin-converting enzyme-2 (ACE2) in periodontal compartments containing periodontal infections to determine if ACE2 is directly or indirectly responsible for the inflammation in periodontal tissues getting worse. In this study, six non-COVID-19 periodontitis patients without diabetes served as controls, and 23 hospitalized periodontitis patients were admitted with PCR-confirmed COVID-19 with diabetes mellitus (Group 1/G1, n = 10), and without diabetes (Group 2/G2, n = 13). We evaluated the mRNA expression of ACE2, IL-6, IL-8, complement C3, and LL-37, as well as the relative proportion of Porphyromonas gingivalis, Fusobacterium nucleatum, and Veillonella parvula to represent the dysbiosis condition in periodontal microenvironment using subgingival plaque and gingival crevicular fluids (GCF) samples and quantitative real time PCR (qPCR). Every analysis was done to ascertain how they related to one another. The area under the curve (AUC) and receiver operating characteristic (ROC) curve were used to determine the sensitivity and specificity of inflammatory indicators. All the grouped patients had ACE2 detected, according to our findings, but only the G1 patients had a positive correlation (p < 0.05) between ACE2 expression and the inflammatory markers. The combination of IL-6 and C3 mRNAs was found to be 0.78 and 0.55 for the G1 group and the G2 group, respectively, based on the ROC and AUC values. According to our research, the relationship between complement C3 and IL-6 may be able to predict the degree of periodontal inflammation in COVID-19 patients who also have diabetes.

The utility of salivary CRP and IL-6 as a non-invasive measurement evaluated in patients with COVID-19 with and without diabetes

Background

The available evidence suggests that inflammatory responses, in both systemic and oral tissue, contribute to the pathology of COVID-19 disease. Hence, studies of inflammation biomarkers in oral fluids, such as saliva, might be useful to better specify COVID-19 features.

Methods

In the current study, we performed quantitative real-time PCR to measure salivary levels of C-reactive protein (CRP) and interleukin-6 (IL-6) in saliva obtained from patients diagnosed with mild COVID-19, in a diabetic group (DG; n = 10) and a non-diabetic group (NDG; n = 13). All participants were diagnosed with periodontitis, while six participants with periodontitis but not diagnosed with COVID-19 were included as controls.

Results

We found increases in salivary total protein levels in both the DG and NDG compared to control patients. In both groups, salivary CRP and IL-6 levels were comparable. Additionally, the levels of salivary CRP were significantly correlated with total proteins, in which a strong and moderate positive correlation was found between DG and NDG, respectively. A linear positive correlation was also noted in the relationship between salivary IL-6 level and total proteins, but the correlation was not significant. Interestingly, the association between salivary CRP and IL-6 levels was positive. However, a moderately significant correlation was only found in COVID-19 patients with diabetes, through which the association was validated by a receiver operating curve.

Conclusions

These finding suggest that salivary CRP and IL-6 are particularly relevant as potential non-invasive biomarker for predicting diabetes risk in mild cases of COVID-19 accompanied with periodontitis.

Herpesviruses and SARS-CoV-2: Viral Association with Oral Inflammatory Diseases

The oral cavity is a niche for diverse microbes, including viruses. Members of the Herpesviridae family, comprised of dsDNA viruses, as well as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), an ssRNA virus, are among the most prevalent viruses infecting the oral cavity, and they exhibit clinical manifestations unique to oral tissues. Viral infection of oral mucosal epithelia triggers an immune response that results in prolonged inflammation. The clinical and systemic disease manifestations of HHV have been researched extensively, and several recent studies have illuminated the relationship between HHV and oral inflammatory diseases. Burgeoning evidence suggests the oral manifestation of SARS-CoV-2 infection includes xerostomia, dysgeusia, periodontal disease, mucositis, and opportunistic viral and bacterial infections, collectively described as oral post-acute sequelae of COVID-19 (PASC). These diverse sequelae could be a result of intensified immune responses initially due to the copious production of proinflammatory cytokines: the so-called "cytokine storm syndrome", facilitating widespread oral and non-oral tissue damage. This review explores the interplay between HHV, SARS-CoV-2, and oral inflammatory diseases such as periodontitis, endodontic disease, and peri-implantitis. Additionally, the review discusses proper diagnostic techniques for identifying viral infection and how viral diagnostics can lead to improved overall patient health.

Convergence of inflammatory response: Salivary cytokine dynamics in coronavirus disease 2019 and periodontal disease

Background

Periodontal disease is associated with immune dysregulation, and cytokines released can add on to the coronavirus disease 2019 (COVID-19)-associated cytokine storm, further worsening the related adverse outcomes. Specific studies investigating cytokine levels in COVID-19 patients with periodontal disease are lacking. Examining the correlation between these conditions could aid in categorizing risk categories, determining referrals, and strengthening oral hygiene protocols. The current study sought to evaluate cytokine levels in the saliva of COVID-19-positive patients with and without periodontal disease.

Materials and Methods

Twenty-six COVID-19-positive patients were subjected to periodontal examination, saliva collection, and assessment of cytokine levels through cytokine bead-based multiplex assay, using fluorescence-encoded beads with flow cytometry (BD FACS LSRFortessa). Eleven cytokines were assessed (interleukin [IL] 2, 4, 6, 10, 17A, and interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-α), chemokine ligand 2 (CCL2/monocyte chemoattractant protein-1), C-X-C motif chemokine ligand (CXCL) 8/IL 8, CXCL 9/monokine-induced gamma interferon [MIG]), and CXCL 10 (chemokine IFN-gamma inducible protein 10 kDa). The cytokine levels of the recruited subjects were also compared graphically with the salivary cytokine levels reported in the literature for health, COVID-19, and periodontal disease alone.

Results

Out of 26 COVID-19-positive patients, 17 had periodontal disease. Levels of all cytokines were raised in patients with both diseases when compared to values reported in literature for health, periodontal disease alone, or COVID-19 alone. However, there was no statistical difference among the recruited subjects for IL-2, IL-4, IL-6, IL-10, IL-17A, IFN-gamma, TNF-α, CCL2, CXCL 8, and CXCL 10. MIG levels were found to be higher in periodontally healthy, COVID-19-positive subjects (P = 0.01).

Conclusions

Periodontal disease might contribute to the COVID-19-induced cytokine storm, potentially amplifying its impact.

Clinical, immunological, and microbiological analysis of the association between periodontitis and COVID-19: a case-control study

PURPOSE

Periodontitis and coronavirus disease (COVID-19) share risk factors and activate similar immunopathological pathways, intensifying systemic inflammation. This study investigated the clinical, immunological and microbiological parameters in individuals with COVID-19 and controls, exploring whether periodontitis-driven inflammation contributes to worsening COVID-19 endpoints.

METHODS

Case (positive RT-PCR for SARS-CoV-2) and control (negative RT-PCR) individuals underwent clinical and periodontal assessments. Salivary levels of TNF-α, IL-6, IL-1β, IL-10, OPG, RANKL, neutrophil extracellular traps, and subgingival biofilm were analyzed at two timepoints. Data on COVID-19-related outcomes and comorbidity information were evaluated from medical records.

RESULTS

Ninety-nine cases of COVID-19 and 182 controls were included for analysis. Periodontitis was associated with more hospitalization (p = 0.009), more days in the intensive care unit (ICU) (p = 0.042), admission to the semi-ICU (p = 0.047), and greater need for oxygen therapy (p = 0.042). After adjustment for confounders, periodontitis resulted in a 1.13-fold increase in the chance of hospitalization. Salivary IL-6 levels (p = 0.010) were increased in individuals with COVID-19 and periodontitis. Periodontitis was associated with increased RANKL and IL-1β after COVID-19. No significant changes were observed in the bacterial loads of the periodontopathogens Porphyromona gingivalis, Aggregatibacter actinomycetemcomitans, Tanerella forsythia, and Treponema denticola.

CONCLUSIONS

Periodontitis was associated with worse COVID-19 outcomes, suggesting the relevance of periodontal care to reduce the burden of overall inflammation. Understanding the crosstalk between SARS-CoV-2 infection and chronic conditions such as periodontitis that can influence disease outcome is important to potentially prevent complications of COVID-19.

Immunoglobulin A response to SARS-CoV-2-N-protein potentially persists in oral fluids of patients with periodontitis six months after mRNA vaccine administration

Few studies have investigated the mucosal immune response after BNT162b2-booster vaccination in individuals with periodontitis. In this study, we evaluated the persistence of IgA anti-SARS-CoV-2-N-protein in saliva and gingival crevicular fluid (GCF) of patients with periodontitis for at least six months post BNT162b2 vaccine booster. We included patients with moderate (n = 7) and severe (n = 7) periodontitis and participants without periodontitis (n = 7) as controls. The Bradford method measured the protein concentrations in the samples, and an enzyme-linked immunosorbent assay of the SARS-CoV-2 N protein was performed to analyze the targeted IgA level. For the tested SARS-CoV-2 antigen (N-protein), IgA levels in saliva and GCF showed a strong and significant correlation. Therefore, in patients with moderate or severe periodontitis, saliva and GCF can provide information regarding the IgA response against SARS-CoV-2-N-protein. The neutralizing activity of IgA against SARS-CoV-2 was not investigated in this study, necessitating further research.

COVID-19 on Oral Health: A New Bilateral Connection for the Pandemic

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and transmission are generally known to be produced by respiratory droplets and aerosols from the oral cavity (O.C.) of infected subjects, as stated by the World Health Organization. Saliva also retains the viral particles and aids in the spread of COVID-19. Angiotensin-converting enzyme Type 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) are two of the numerous factors that promote SARS-CoV-2 infection, expressed by O.C. structures, various mucosa types, and the epithelia of salivary glands. A systemic SARS-CoV-2 infection might result from viral replication in O.C. cells. On the other hand, cellular damage of different subtypes in the O.C. might be associated with various clinical signs and symptoms. Factors interfering with SARS-CoV-2 infection potential might represent fertile ground for possible local pharmacotherapeutic interventions, which may confine SARS-CoV-2 virus entry and transmission in the O.C., finally representing a way to reduce COVID-19 incidence and severity.

Unvaccinated periodontal patients with a history of COVID-19: clinical findings in a Dental School setting

This study analyzed the periodontal clinical data of individuals with a history of COVID-19 treated in a dental school during the pandemic in 2021 before vaccination.

METHODS

This analysis included individuals older than 18 years with no history of systemic disorders other than systemic arterial hypertension. Individuals who had COVID-19 were classified according to the World Health Organization as asymptomatic, with mild, moderate, severe, or critical symptoms.

RESULTS

A total of 95 individuals were evaluated, which included 24 with a history of COVID-19. Seventeen percent had been asymptomatic, 21% had mild, 25% moderate, 21% severe, and 17% critical symptoms, including intubation. Individuals with no history of COVID-19 presented significantly lower measurements of probing depth (p=0.003; Mann-Whitney test) and clinical attachment level (p=0.002) compared to individuals with a history of COVID-19. A significant negative association was found between bleeding on probing and the severity of characteristics of COVID-19 (rho= -0.233; p=0.023). Conversely, positive associations between the values of probing depth (rho= 0.292; p=0.004) and mean clinical attachment level (rho= 0.300; p=0.003) and the characteristics of COVID-19 were found.

CONCLUSIONS

The periodontal data shows that patients who had COVID-19 before vaccination may present a worse periodontal status when compared to patients in the same clinical setting with no history of COVID-19. However, a more extensive study should confirm it with more participants.

Sugar-sweetened beverages and periodontal disease: A systematic review

This systematic review aims to determine the association between the consumption of sugar-sweetened beverages (SSBs) and periodontal disease. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed to conduct a literature search on five electronic databases till January 2022. Systemically healthy individuals consuming SSBs and presenting periodontal disease (gingivitis/periodontitis) were included. The modified Newcastle-Ottawa Scale and the Grading of Recommendation Assessment Development and Evaluation criteria were respectively used to assess the risk of bias and the evidence's quality. Of the 1303 eligible records identified in the initial search, ten studies (nine cross-sectional and one case-control) were selected for the final review. Among the included articles, five reported SSBs intake in the form of carbonated soft drinks, two as sugary drinks, two as soft drinks, and one as coffee with added sugar. Four studies reported gingivitis as an outcome, while the remaining six studies reported periodontitis using validated indices. The included studies were of medium to high quality. Consumption of SSBs may increase gingival bleeding, thereby gingivitis and the risk of periodontitis. Intake of added sugars like SSBs should be considered as a potential factor during gingival/periodontal risk assessment. Further studies are warranted to establish additional evidence of association.

Active Matrix Metalloproteinase-8 (aMMP-8) Versus Total MMP-8 in Periodontal and Peri-Implant Disease Point-of-Care Diagnostics

Active matrix metalloproteinase-8 (aMMP-8) is a promising biomarker candidate for the modern periodontal and peri-implant disease diagnostics utilizing the chairside/point-of-care oral fluid technologies. These rapid biomarker analysis technologies utilize gingival crevicular fluid (GCF), peri-implant sulcular fluid (PISF), or mouth rinse as the oral fluid matrices that can be collected patient-friendly and non-invasively without causing bacteremia. aMMP-8, but not total or latent proMMP-8, has been shown to be a relevant biomarker to be implemented to the latest 2017 classification system of periodontitis and peri-implantitis. Thus, aMMP-8 point-of-care-testing (POCT)-but not total or latent proMMP-8-can be conveniently used as an adjunctive and preventive diagnostic tool to identify and screen the developing and ongoing periodontal and peri-implant breakdown and disease as well as predict its episodic progression. Similarly, aMMP-8 POCT provides an important tool to monitor the treatment effect of these diseases, but also other diseases such as head and neck cancer, where it can identify and predict the rapid tissue destructive oral side-effects during and after the radiotherapy. Additionally, recent studies support aMMP-8 POCT benefitting the identification of periodontitis and diabetes as the escalating risk diseases for COVID-19 infection. Overall, aMMP-8 POCT has launched a new clinical field in oral medicine and dentistry, i.e., oral clinical chemistry.

The Potential of Collagen Treatment for Comorbid Diseases

Collagen, the most abundant protein in our bodies, plays a crucial role in maintaining the structural integrity of various tissues and organs. Beyond its involvement in skin elasticity and joint health, emerging research suggests that collagen may significantly impact the treatment of complex diseases, particularly those associated with tissue damage and inflammation. The versatile functions of collagen, including skin regeneration, improving joint health, and increasing bone strength, make it potentially useful in treating different diseases. To the best of my knowledge, the strategy of using collagen to treat comorbid diseases has not been widely studied. This paper aims to explore the potential of collagen in treating comorbid diseases, including rheumatoid arthritis, osteoarthritis, osteoporosis, psoriatic arthritis, sarcopenia, gastroesophageal reflux, periodontitis, skin aging, and diabetes mellitus. Collagen-based therapies have shown promise in managing comorbidities due to their versatile properties. The multifaceted nature of collagen positions it as a promising candidate for treating complex diseases and addressing comorbid conditions. Its roles in wound healing, musculoskeletal disorders, cardiovascular health, and gastrointestinal conditions highlight the diverse therapeutic applications of collagen in the context of comorbidity management.

Increased odds for COVID-19 infection among individuals with periodontal disease

OBJECTIVES

Periodontal disease has been linked to multiple systemic conditions, but the relationship with COVID-19 still needs to be elucidated. We hypothesized that periodontal disease may be associated with COVID-19 infection.

MATERIALS AND METHODS

This study utilized cross-sectional data to establish the strength of the association between periodontal disease and COVID-19 infection. The University of Florida Health Center's i2b2 patient's registry was used to generate patient counts through ICD-10 diagnostic codes. Univariate descriptive statistics of the patient population and logistic regression to estimate odds ratios of associations between periodontal disease and COVID-19 infection were used for analysis.

RESULTS

Patients with periodontal disease were 4.4 times more likely to be positively diagnosed with COVID-19 than patients without PD. Associations remained similar and robust (P value < 0.0001) after adjustment for age (OR = 4.34; 95% CI, 3.68-5.09), gender (OR = 4.46; 95% CI, 3.79-5.23), and smoking status (OR = 4.77; 95% CI, 4.04-5.59). Associations were smaller but remained robust (P value < 0.0001) after adjusting for race (OR = 2.83; 95% CI, 2.40-3.32), obesity (OR = 2.53; 95% CI, 2.14-2.98), diabetes (OR = 3.32; 95% CI, 2.81-3.90), and cardiovascular disease (OR = 2.68; 95% CI, 2.27-3.14).

CONCLUSIONS

Periodontal disease is significantly associated with increased odds for COVID-19 infection.

CLINICAL RELEVANCE

With the caveat of a cross-sectional study design, these results suggest that periodontal disease may increase the odds for COVID-19 infection.

Association between periodontal diseases and COVID-19 infection: a case-control study with a longitudinal arm

Some studies have suggested potential relationships between periodontal disease and COVID-19, explained by many possible pathological pathways. The aim of this case-control study with a longitudinal arm was to investigate this association. 80 systemically healthy individuals (apart from COVID-19) were involved in this study, divided into 40 patients who had recently had COVID-19 (test, divided into severe and mild/moderate cases) and 40 who had not had COVID-19 (control). Clinical periodontal parameters and laboratory data were recorded. Mann-Whitney U test, Wilcoxon test, and chi-square test were performed to compare variables. Multiple binary logistic regression method was used to estimate adjusted ORs and 95% confidence interval. Hs-CRP-1 and 2, Ferritin-1 and 2, lymphocyte count-1 values, and neutrophil/lymphocyte ratio-1 were higher in patients with severe COVID-19 than patients with mild/moderate COVID-19 (p < 0.05). All of these laboratory values significantly decreased after COVID-19 treatment (p < 0.05) in the test group. Presence of periodontitis (p = 0.015) was higher and periodontal health was lower (p = 0.002) in the test group than in the control group. All clinical periodontal parameters were significantly higher in the test group than in the control group (p < 0.05), except plaque index. Prevalence of periodontitis was associated with increased odds of having COVID-19 infection (PR = 1.34; 95% CI 0.23-2.45) in the multiple binary logistic regression. COVID-19 is associated with periodontitis prevalence, through a series of possible mechanisms including local and systemic inflammatory responses. Further studies should investigate whether the maintenance of periodontal health may be a factor in the reduction of the severity of COVID-19 infections.

Estimating the prevalence of oral manifestations in COVID-19 patients: a systematic review

BACKGROUND

Patients with coronavirus disease 2019 (COVID-19) present with a variety of oral manifestations. Therefore, we conducted a systematic review to estimate the prevalence of oral lesions among COVID-19 patients.

METHODS

An extensive literature search of several electronic bibliographic databases (PubMed, Scopus, Science Direct, Litcovid) was conducted to retrieve all articles published in the English language from January 1, 2020 to March 31, 2023 that reported the prevalence of oral manifestations among COVID-19 patients. A meta-analysis of pooled prevalence was performed using Jamovi ver. 2.3 (2022). The I2 and Q statistics were used to assess heterogeneity between studies, and p-values <0.01 were considered statistically significant.

RESULTS

In total, 79 studies with data from 13,252 patients were included. The articles were predominantly published in 2020 (n=33), and Italy was the most common country (n=14). Most of the affected patients more than 50 years old and women (56.6%). The most common sites of involvement were the tongue (n=65), followed by the oral mucosa (n=37) and lips (n=19). High heterogeneity was found between studies. The most common oral manifestation was taste alteration, followed by xerostomia and ulceration, showing pooled prevalence rates of 48%, 35%, and 21%, respectively.

CONCLUSION

COVID-19 patients show various oral manifestations that may help clinicians identify the disease promptly. Recognition of the signs and symptoms of COVID-19 is critical for an early diagnosis and better prognosis.

The impact of periodontal disease on the clinical outcomes of COVID-19: A systematic review and meta-analysis

BACKGROUND

A possible relationship between periodontitis (PD) and COVID-19 and its adverse outcomes has been suggested. Hence, the present systematic review and meta-analysis aimed to investigate the available evidence regarding the potential association between periodontitis (PD) and COVID-19 and its adverse outcomes.

MATERIALS AND METHODS

PubMed, Scopus, Web of Science, and Google Scholar were searched for relevant studies published up to April 15th, 2023. Studies that evaluated the association between PD and COVID-19 were included. Risk of bias was evaluated by two reviewers, and meta-analyses were performed using RevMan 5.3 software.

RESULTS

A total of 22 studies involving 92,535 patients from USA, Europe, Asia, the Middle East and South America were included; of these, 12 were pooled into the meta-analysis. Most of the studies (19 studies) reported a significant association between PD and COVID-19. The pooled data found a significant association between PD and COVID-19 outcomes: more severe symptoms (OR = 6.95, P = 0.0008), ICU admissions (OR = 3.15, P = 0.0001), and mortality (OR = 1.92, P = 0.21). Additionally, compared to mild PD, severe PD was significantly associated with higher risks of severe COVID-19 outcomes: severe symptoms (P = 0.02); ICU admission (P = 0.0001); and higher mortality rates (P = 0.0001). The results also revealed 58% higher risk for COVID-19 infection in patients with PD (P = 0.00001).

CONCLUSIONS

The present findings suggest a possible association between poor periodontal health and the risk of poor COVID-19 outcomes. However, owing to the observed methodological heterogeneity across the included studies, further prospective cohort studies with standardized methodologies are warranted to further unravel the potential association between periodontal disease and COVID-19 and its adverse outcomes.

Microstructured Polymer System Containing Proanthocyanidin-Enriched Extract from Limonium brasiliense as a Prophylaxis Strategy to Prevent Recurrence of Porphyromonas gingivalis

Periodontal diseases are a global oral health problem affecting almost 10% of the global population. Porphyromonas gingivalis is one of the main bacteria involved in the initiation and progression of inflammatory processes as a result of the action of the cysteine proteases lysin- and arginine-gingipain. Surelease/polycarbophil microparticles containing a lyophilized proanthocyanidin-enriched fraction from the rhizomes of Limonium brasiliense, traditionally named "baicuru" (ethyl acetate fraction), were manufactured. The ethyl acetate fraction was characterized by UHPLC by the presence of samarangenins A and B (12.10 ± 0.07 and 21.05 ± 0.44%, respectively) and epigallocatechin-3-O-gallate (13.44 ± 0.27%). Physiochemical aspects of Surelease/polycarbophil microparticles were characterized concerning particle size, zeta potential, entrapment efficiency, ethyl acetate fraction release, and mucoadhesion. Additionally, the presence of the ethyl acetate fraction-loaded microparticles was performed concerning potential influence on viability of human buccal KB cells, P. gingivalis adhesion to KB cells, gingipain activity, and P. gingivalis biofilm formation. In general, all Surelease/polycarbophil microparticles tested showed strong adhesion to porcine cheek mucosa (93.1 ± 4.2% in a 30-min test), associated with a prolonged release of the ethyl acetate fraction (up to 16.5 ± 0.8% in 24 h). Preincubation of KB cells with Surelease/polycarbophil microparticles (25 µg/mL) resulted in an up to 93 ± 2% reduced infection rate by P. gingivalis. Decreased activity of the P. gingivalis-specific virulence factors lysin- and arginine-gingipain proteases by Surelease/polycarbophil microparticles was confirmed. Surelease/polycarbophil microparticles decreased biofilm formation of P. gingivalis (97 ± 2% at 60 µg/mL). Results from this study prove the promising activity of Surelease/polycarbophil microparticles containing ethyl acetate fraction microparticles as a prophylaxis strategy to prevent the recurrence of P. gingivalis.

Prevalence of oral complications in the course of severe SARS-CoV-2 infection under mechanical non-invasive ventilation

BACKGROUND

The management of oral health during severe symptoms of Covid-19 is still a challenge, especially in intensive care units under invasive/noninvasive ventilation in hospital. Understanding the cause-and-effect relationships may allow for individual adjustment of oral care recommendations during Covid-19 disease. The study's objective was to assess Covid-19 patients' oral health status under hospital treatment due to pulmonary adverse Covid-19 outcomes.

MATERIAL AND METHODS

Covid-19 patients (mean age 74.4 ± 15.4; n = 120, male n = 50/female n = 70) were admitted to hospital in the acute phase of Covid-19 between January and March 2022 who required oxygen therapy due to pneumonia, rapid respiratory failure, low saturation. Blood and radiological tests were taken according to National Health Fund guidelines. The condition of teeth (Decayed, Missing, Filled teeth as DMFT index), dental hygiene (Plaque Control Record as PCR index), periodontal status (probing depth PD, clinical attachment CAL, bleeding on probing BOP) and oral mucosa (BRUSHED and Beck scores) were examined.

RESULTS

Charateristics of the teeth (dental caries 35.2%, DMFT Median 22), plaque retention (83.4%), advanced periodontitis (48.3%), xerostomia (74.2%), oral mucosa inflammation (80.8%), angular cheilitis (53.3%), hemorrhagic (21.7%) showed a high incidence of harmful oral conditions. BRUSHED model and Beck score indicated moderate oral dysfunction and need for oral care every 8 h. Spearman's analysis revealed a significant positive correlation between pneumonia and neutrophile, interleukin-6 IL-6, C-reactive protein CRP (p = 0.01, p < 0.001, p < 0.001), negative to lymphocyte count (p < 0.001). Multiple and logistic regressions selected the following risk predictors for pneumonia as IL-6, CRP, obesity and for severe COVID-19 symptoms D-dimer level and a lack of targeted vaccination (p < 0.001). Among oral predictors, the PCR index and Beck score were significant for both outcomes (respectively p < 0.001, p < 0.012). Patients who received oxygen therapy with face masks had more often angular heilitis and debris (p = 0.025, p = 0.035).

CONCLUSIONS

COVID-19 hospitalised patients with severe symptoms crossing with poor oral health-related conditions. This may exacerbate a response for COVID infection, and play a role in cytokine storm. For Covid-19 management, to inhibit extraoral/intraoral complications, it is recommended to adjust oral hygiene procedures, including antibacterial, protective, moisturising agents after individual oral health assessment.

Association between the severity of periodontitis, COVID-19, C-reactive protein and interleukin-6 levels in hospitalized patients: a case‒control study

BACKGROUND

The COVID-19 pandemic is perhaps one of the most important events of the 21st century. Periodontitis is one of the most prevalent diseases of the oral cavity. Due to possible pathways of interaction between these two diseases, we investigated their association.

METHODS

The study population consisted of hospitalized patients with established COVID-19 diagnoses. Patients with mild to moderate COVID-19 were considered controls, while cases had severe to critical COVID-19. Periodontal examination and serum and saliva sampling were performed for each patient. Relevant medical data were extracted from patients' hospital files.

RESULTS

Of the enrolled patients, 122 were included in the statistical analyses. The severity of periodontitis was directly and significantly correlated with the severity of COVID-19 (P < 0.001). Patients with generalized stage III or IV periodontitis displayed an adjusted odds ratio of 4.24 for severe to critical COVID-19. Salivary and serum interleukin-6 levels were significantly associated with COVID-19 severity (P values: 0.002 and 0.004, respectively). Hospitalization length was significantly associated with the severity of periodontitis (P = 0.004). Clinical attachment level and gingival index were associated with increased odds for adverse events (P values: 0.004 and 0.035, respectively), while number of remaining teeth was associated with decreased odds for adverse events (P = 0.023).

CONCLUSIONS

This study showed that the severity of periodontitis is associated with the severity of COVID-19. This association might manifest as increased odds of adverse events. COVID-19 severity was associated with higher levels of salivary and serum interleukin-6 levels.

Adult Mesenchymal Stem Cells from Oral Cavity and Surrounding Areas: Types and Biomedical Applications

Adult mesenchymal stem cells are those obtained from the conformation of dental structures (DMSC), such as deciduous and permanent teeth and other surrounding tissues. Background: The self-renewal and differentiation capacities of these adult stem cells allow for great clinical potential. Because DMSC are cells of ectomesenchymal origin, they reveal a high capacity for complete regeneration of dental pulp, periodontal tissue, and other biomedical applications; their differentiation into other types of cells promotes repair in muscle tissue, cardiac, pancreatic, nervous, bone, cartilage, skin, and corneal tissues, among others, with a high predictability of success. Therefore, stem and progenitor cells, with their exosomes of dental origin and surrounding areas in the oral cavity due to their plasticity, are considered a fundamental pillar in medicine and regenerative dentistry. Tissue engineering (MSCs, scaffolds, and bioactive molecules) sustains and induces its multipotent and immunomodulatory effects. It is of vital importance to guarantee the safety and efficacy of the procedures designed for patients, and for this purpose, more clinical trials are needed to increase the efficacy of several pathologies. Conclusion: From a bioethical and transcendental anthropological point of view, the human person as a unique being facilitates better clinical and personalized therapy, given the higher prevalence of dental and chronic systemic diseases.

Cranial nerve involvement among COVID-19 survivors

Introduction

COVID-19 was first reported in November 2019 in China and rapidly spread across the globe. COVID-19 causes neurologic symptoms and complications, which may persist even after recovery in patients. The objective of this research was to determine the involvement of cranial nerves in COVID-19 survivors.

Method

This was a retrospective study. The study was conducted between March and July of 2022. The analysis included 98 patients with a certain positive polymerase chain reaction. SPSS software version 19 was utilized for data analysis.

Results

The average age of the participants was 40.47 years (8.81). The olfactory nerve was found to be the most frequently involved cranial nerve (36.7%). Over 20% of participants had a taste disorder. The findings from the regression analysis indicated that lung involvement and age have a direct and significant relationship with cranial nerve involvement and can serve as its predictors (p = 0.001).

Conclusion

It seems that cranial nerve involvement was sustained in COVID-19 patients who survived. In addition, elderly patients and patients with severe illnesses were more likely to show cranial symptoms. It is necessary to monitor COVID-19 survivors for neurological symptoms.

Relationship between periodontitis and COVID-19: A bidirectional two-sample Mendelian randomization study

Background and Aims

Coronavirus disease (COVID-19) is a major danger to world health and has been linked to periodontitis in a number of epidemiological observational studies. However, it is unclear whether COVID-19 causes periodontitis. COVID-19's causal influence on periodontitis was determined using bidirectional Mendelian randomization (MR).

Methods

Large-scale COVID-19 and periodontitis genome wide association study data were analyzed. Inverse variance weighting, MR-Egger, weighted median, and MR-PRESSO were used to estimate causal effects. Sensitivity studies were conducted using the Cochran's Q test, the MR-Egger intercept test, the MR-PRESSO, and the leave-one-out (LOO) analysis. Further investigation of potential mediating factors was performed using risk factor analysis.

Results

The MR presented no causal relationship between periodontitis and hospitalization for COVID-19 (odds ratio [OR] = 0.97, 95% confidence interval [CI] 0.78-1.20; p = 0.76), vulnerability to COVID-19 (OR = 1.04, 95% CI 0.88-1.21; p = 0.65), COVID-19 disease severity (OR = 1.01, 95% CI 0.92-1.11; p = 0.81). Meanwhile, a noncausal effect of genetic hospitalization for COVID-19, illness severity, and vulnerability to periodontitis was detected. Other MR methods yielded identical results to inverse variance weighting. According to sensitivity analysis, horizontal pleiotropy is unlikely to affect causal estimation.

Conclusion

Periodontitis had no link to the risk of COVID-19 hospitalization, susceptibility, or severity. However, the substance in COVID-19 that is responsible for this effect must be studied further.

The underlying molecular mechanisms and biomarkers between periodontitis and COVID-19

OBJECTIVE

Emerging evidence shows the clinical consequences of patient with COVID-19 and periodontitis are not promising, and periodontitis is a risk factor. Periodontitis and COVID-19 probably have a relationship. Hence, this study aimed to identify the common molecular mechanism that may help to devise potential therapeutic strategies in the future.

MATERIAL AND METHODS

We analyzed two RNA-seq datasets for differential expressed genes, enrichment of biological processes, transcription factors (TFs) and deconvolution-based immune cell types in periodontitis, COVID-19 and healthy controls. Relationships between TFs and mRNA were established by Pearson correlation analysis, and the common TFs-mRNA regulatory network and nine co-upregulated TFs of the two diseases was obtained. The RT-PCR detected the TFs.

RESULTS

A total of 1616 and 10201 differentially expressed gene (DEGs) from periodontitis and COVID-19 are found. Moreover, nine shared TFs and common biological processes associated with lymphocyte activation involved in immune response were identified across periodontitis and COVID-19. The cell type enrichment revealed elevated plasma cells among two diseases. The RT-PCR further confirmed the nine TFs up-regulation in periodontitis.

CONCLUSION

The pathogenesis of periodontitis and COVID-19 is closely related to the expression of TFs and lymphocyte activation, which can provide potential targets for treatment.

Catastrophic out-of-pocket payments for dental treatment: regional evidence from Spain

BACKGROUND

To estimate the incidence and concentration of catastrophic out-of-pocket payments for healthcare and dental treatment, by region in Spain (calculated as the proportion of households needing to exceed a given threshold of their income to make these payments) in 2008, 2011 and 2015.

METHODS

The data analysed were obtained from the Spanish Family Budget Survey reports for the years in question. The study method was that proposed by Wagstaff and van Doorslaer (2003), contrasting payments for dental treatment versus household income and considering thresholds of 10%, 20%, 30% and 40%, thus obtaining incidence rates. In addition, relevant sociodemographic variables were obtained for each household included in the study.

RESULTS

With some regional heterogeneity, on average 4.75% of Spanish households spend more than 10% of their income on dental treatment, and 1.23% spend more than 40%. Thus, 38.67% of catastrophic out-of-pocket payments for dental services in Spain corresponds to payments at the 10% threshold. This value rises to 55.98% for a threshold of 40%.

CONCLUSIONS

An important proportion of catastrophic out-of-pocket payments for health care in Spain corresponds to dental treatment, a service that has very limited availability under the Spanish NHS. This finding highlights the need to formulate policies aimed at enhancing dental cover, in order to reduce inequalities in health care and, consequently, enhance the population's quality of life and health status.

Hematologic tests and their association with the severity of COVID-19 and periodontitis in hospitalized patients: a case-control study

BACKGROUND

The presence of comorbidities, especially those with a chronic inflammatory nature such as periodontitis, can facilitate COVID-19 progression toward more severe forms. Both of these diseases can affect systemic health and alter hematological test results. In this study, we decided to investigate COVID-19 and periodontitis' possible interaction with these alterations.

METHODS

Hospitalized patients with a definitive diagnosis of COVID-19 were included. Controls had mild to moderate COVID-19, while cases had severe to critical COVID-19. Periodontal examination was done for each patient. Relevant medical and hematological data were extracted from patient's hospital files.

RESULTS

A total of 122 patients entered the final analysis. The minimum white blood cell counts were associated with the severity of periodontitis. The interaction between periodontitis and COVID-19 was associated with increased minimum white blood cell counts and decreased platelet counts. COVID-19 severity was associated with increased venous oxygen saturation, prothrombin time, the maximum partial thromboplastin time, the maximum and average urea, the maximum creatinine, the maximum potassium, and lactate dehydrogenase, and decreased sodium levels.

CONCLUSIONS

Results of this study showed that several blood parameters were associated with periodontitis, COVID-19, or the interaction between them.

Promoting Oral Health for Patients with Special Needs

The problem of poor oral health among people with disabilities is common in many low-, middle- and high-income countries [...].