The Bidirectional Association Between Periodontitis and COVID-19: A Review of Current Evidence (preprint)

The COVID-19 pandemic has brought marked changes worldwide to the management of airborne infectious diseases. It sparked the development of the SARS-CoV-2 vaccine and pharmacotherapeutics to prevent infection and increase the survival rate during the acute viral phase and the comorbidities associated with COVID-19. Periodontal disease may increase the morbidity and perhaps the mortality of a COVID-19 infection. However, the molecular interaction between periodontitis and COVID-19 infection remains undetermined. A potential pathogenic co-morbidity may involve periodontal pathogenic release of destructive cytokines in the highly inflamed connective tissue and risk for COVID-19. Additional biomarkers such as C-reactive proteins appear to play a role for risk and pathogenesis of COVID-19. The potential of herpesviruses, especially as it is related to aggressive periodontitis may also be a comorbidity for COVID-19. This paper reviews available evidence on the bidirectional association between periodontitis and COVID-19.

Periodontal Maintenance in a Patient with a Lung Transplantation Post-COVID-19 Infection.

Early dental screening and treatment before and after solid organ transplantation are recommended infection prophylaxis measures. Dental treatment after transplantation should only be rendered after a discussion with the patient's health-care provider and/or transplant surgeon to determine the patient's stability for dental care. Potential sources of acute or chronic oral infections should be evaluated at every visit. Periodontal evaluation and through dental prophylaxis should be performed. Oral hygiene instruction including the importance of maintaining excellent oral health after transplant should be reviewed.

Association between periodontal diseases and cardiovascular diseases, diabetes and respiratory diseases: Consensus report of the Joint Workshop by the European Federation of Periodontology (EFP) and the European arm of the World Organization of Family Doctors (WONCA Europe).

AIM: To explore the implications for dentists and family doctors of the association between periodontal and systemic diseases and the role of dentists and family doctors in managing non-communicable diseases (NCDs) and promoting healthy lifestyles. MATERIALS AND METHODS: The consensus reports of the previous Focused Workshops on the associations between periodontitis and diabetes (2017) and periodontitis and cardiovascular diseases (2019) formed the technical reviews to underpin discussions on both topics. For the association with respiratory diseases, a systematic review was specifically commissioned for the Workshop discussions. Working groups prepared proposals independently, and then the proposals were discussed and approved at plenary meetings. RESULTS: Periodontitis is independently associated with cardiovascular diseases, diabetes, chronic obstructive pulmonary disease (COPD), obstructive sleep apnea and COVID-19 complications. Dentists and family doctors should collaborate in managing NCDs, implementing strategies for early detection of periodontitis in primary care centres and of cardiovascular diseases or diabetes in dental settings. Family doctors should be informed about periodontal diseases and their consequences, and oral health professionals (OHPs) should be informed about the relevance of NCDs and the associated risk factors. CONCLUSIONS: Closer collaboration between OHPs and family doctors is important in the early detection and management of NCDs and in promoting healthy lifestyles. Pathways for early case detection of periodontitis in family medicine practices and of NCDs in dental practices should be developed and evaluated.

Association between severity of COVID-19, Periodontal health and disease in Riyadh subpopulation.

Background: Periodontitis and coronavirus disease (COVID-19) both exhibit an exaggerated inflammatory response as common traits. Given that periodontal diseases have been linked to respiratory illnesses like pneumonia, it is quite possible that periodontitis and COVID-19 are related. Therefore, the purpose of the current study was to ascertain whether the severity of COVID-19 and periodontal disease are related. Methods: A retrospective study was done using the 3 years of patients' medical and dental records in the University Hospital. A telephone interview was employed to estimate the severity of symptoms got through COVID-19 infection. The data obtained were subjected to statistical analysis. The Chi-square test, with statistical significance set at 0.05, was used to determine the relationship between the severity of periodontal disease and the severity of COVID-19. Results: It was seen that there was a strong relationship between the severities of COVID-19 disease and periodontal disease. The mildest gingivitis cases (63%), Stage 1 periodontitis (62.9%), were associated with the COVID-19-negative group, whereas the most severe gingivitis cases (85.7%), Stage 4 periodontitis group (66.66%), were associated with COVID-19-positive group. In comparison to those without periodontitis, patients with periodontitis had a 1.54 times higher risk of COVID-19 complications (P = 0.048). Patients who had comorbidities were 2.49 times to have COVID-19 complications (P = 0.02). Conclusion: The observations presented above lead to the conclusion that COVID-19 and periodontal disease severities are related. Understanding the potential association between periodontitis and COVID-19 through systemic inflammation could be a means of achieving a high-quality medical care. To validate the findings, additional research with larger samples is required.

Propolis effects in periodontal disease seem to affect coronavirus disease: a meta-analysis.

This meta-analysis aimed to investigate the effects of propolis on the severity of coronavirus disease symptoms by reducing periodontal disease. PubMed, EMBASE, SciELO, Web of Science, and SCOPUS databases were systematically searched. Studies have been conducted analyzing propolis's effects on COVID-19 and periodontitis. The study was conducted according to the PRISMA statement and registered in PROSPERO. Risk of Bias (RoB) assessment and meta-analysis of clinical studies were performed (Review Manager 5, Cochrane). The certainty of the evidence was assessed using GradePro (GDT). Studies have shown propolis flavonoids inhibit viral replication in several DNA and RNA viruses, including coronaviruses. Propolis components have an aminopeptidase inhibitor activity that can inhibit the main proteases of SARS viruses and seem to inhibit protein spikes, which are sites of most mutations in SARS-CoV strains. The meta-analysis showed favorable results with the use of propolis on probing depth (95%CI: 0.92; p < 0.001), clinical attachment level (95%CI: 1.48; p < 0.001), gingival index (95%CI: 0.14; p = 0.03), plaque index (95%CI: 0.11; p = 0.23), and blending on probing (95%CI: 0.39; p < 0.001). The antibacterial activity of propolis could be mediated through its direct action on microorganisms or the stimulation of the immune system, activating natural defenses. Thus, propolis inhibits the replication of SARS-CoV-2 as well as its bacterial activity. Treatment with propolis improves general health and facilitates the activation of the immune system against coronavirus.

Periodontal disease and COVID-19: Prognosis and potential pathways of association in their pathogenesis.

Objective: The objective of this narrative review is to determine if periodontal disease is a factor in the development of a poor prognosis for COVID-19. Method: A bibliographic search was conducted in PubMed, Virtual Health Library, Google Scholar, and in the databases of Science Direct, Scopus, Lilacs, Bireme, Scielo, and Web of Science, using the following keywords: "COVID-19," "SARS-CoV-2," and "periodontal diseases." Results: Fifty-six records were retrieved from the database searches. After screening, 39 articles were selected for study: 13 reviews, 2 case-control studies, 1 systematic review, 8 letters to the editor, 2 cohort studies, 1 thesis, 7 hypotheses, 1 short communication, 3 commentaries, and 1 scoping review. Discussion: Both periodontal disease and COVID-19 produce an inflammatory response. This immune response generates an over-production of inflammatory cytokines that can harm overall health. Conclusion: The mouth serves as the entryway for many microorganisms that can harm health in general, among them SARS-CoV-2. It is important to maintain good oral health to lower the inflammatory load present in periodontal disease, lessening the possibility of complications from COVID-19.

Objectif: L'objectif de cette revue narrative est de déterminer si la maladie parodontale est un facteur dans le développement d'un mauvais pronostic de la COVID-19. Méthodologie: Une recherche bibliographique a été effectuée dans PubMed, la bibliothèque virtuelle de la santé, Google Scholar, et dans les bases de données de Science Direct, Scopus, Lilacs, Bireme, Scielo, et Web of Science, en utilisant les mots-clés suivants : « COVID-19 ¼, « SRAS-CoV-2 ¼ et « maladie parodontale ¼ (en anglais). Résultats : Cinquante-six dossiers ont été extraits à partir des recherches dans les bases de données. Après la sélection, 39 articles ont été choisis pour l'étude : 13 revues, 2 études cas-témoins, 1 revue systématique, 8 lettres à l'éditeur, 2 études de cohorte, 1 thèse, 7 hypothèses, 1 courte communication, 3 commentaires et 1 examen de la portée. Discussion: La maladie parodontale et la COVID-19 produisent toutes deux une réponse inflammatoire. Cette réponse immunitaire produit une surproduction de cytokines inflammatoires qui peuvent nuire à la santé globale. Conclusion: La bouche sert de voie d'entrée à de nombreux micro-organismes qui peuvent nuire à la santé en général, parmi lesquels le SRAS-CoV-2. Il est important de préserver une bonne santé buccodentaire pour diminuer la charge inflammatoire présente dans la maladie parodontale, réduisant ainsi la possibilité de complications de la COVID-19.

Increased Risk of COVID-19 Infection Among Individuals with Periodontal Disease (preprint)

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 diseases may be associated with Covid 19 infectionMaterials/Methods: This study utilized cross-sectional data to establish the strength of 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 diagnosed periodontal disease were 4.4 times more likely to be positively diagnosed with COVID-19 than patients without periodontal disease. 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 risk for COVID-19 infection.Clinical Relevance: With the caveat of a cross sectional study design, these results suggest that periodontal disease may increase the risk for Covid 19 infection.

Periodontal disease and COVID-19: a systematic review and meta-analysis of observational studies (preprint)

Background: A larger proportion of people with severe cases of Coronavirus Disease 2019 (COVID-19) appears to have comorbidities compared to the general population. However, evidence regarding the roles of periodontal disease(PD), in context of Coronavirus Disease 2019(COVID-19), is limited. Thus, to explore the association between PD and COVID-19, this systematic review and meta analysis was conducted. Methods: 7 online databases were searched by January 31, 2023. Heterogeneity was tested by I2 index. OR and 95% CI were pooled through either random-effect or fixed-effect models. Subgroup analyses, sensitivity analyses, and publication bias assessments were also conducted. Results: Of the 823 articles identified and reviewed, 11 articles with 16,708 subjects met inclusion criteria and were included. PD was found to be associated with a statistically significant increase in risk of progression to severe diseases for COVID-19 patients(OR=2.20, 95% CI=1.38-3.49). Further analysis suggested that  PD was associated with assisted ventilation(OR=5.01, 95% CI:2.61-9.63), ICU admission(OR=1.61, 95% CI:1.24-2.09), pneumonia(OR=5.19, 95% CI:1.17-23.00), and death(OR=2.25, 95% CI:1.55-3.28) for COVID-19 cases. Conclusions: Our results show that individuals with PD have an increased risk for ICU admission, assisted mechanical ventilation therapy, and a significantly increased risk of pneumonia and death. This suggests, to some extent, that the oral cavity is the gateway to COVID-19 infection; in other words, periodontitis is a risk factor for COVID-19 severity.

Factors associated with covid-19 that trigger oral infections in the child population / Factores asociados al covid-19 desencadenantes de infecciones bucodentales en la población infantil

La presencia de un nuevo coronavirus se propagó de manera inesperada alrededor de todo el mundo, desencadenando una crisis mundial sin precedentes. Ya para el año 2020, habían más de 7,9 millones de casos, y 434.796 muertes, en más de 200 países. En ese momento, se implementaron medidas de aislamiento y distanciamiento social en todo el mundo para contener el acelerado propagación de covid-19; entre las consecuencias, las clínicas dentales, se cerraron temporalmente y se suspendió la atención dental electiva, lo que conllevó a un aumento en el desarrollo de enfermedades bucodentales. Con relación a los niños y jóvenes, hubo un aumento en este tipo de enfermedades. Los niños se vieron obligados a pasar la mayor parte de su tiempo en el hogar con la adquisición de hábitos alimentarios incorrectos, ingesta de refrescos y bebidas energéticas que, además de contener altas cantidades de azúcares, su contenido ácido produce erosión dental y hace que el esmalte tejido menos resistente al ataque de bacterias cariogénicas. En este trabajo se analizó una población de 96 niños en edad escolar durante un periodo de dos años de 2020 al 2022. Los resultados mostraron que 100% de los escolares presentaron caries dentales al momento de su evaluación en enero 2022, mientras que 47% del total presentaron dientes obturados y el 64% del total de casos, perdieron algunas de sus piezas dentales. Estos resultados son, posiblemente, debido al desconocimiento de los escolares sobre la higiene para la prevención de las caries dental y sus consecuencias, siendo la más perjudicial la pérdida prematura de dientes temporales, lo que hace necesario implementar programas sobre la promoción y prevención en la salud bucodental en escolares, docentes, y padres y representantes(AU)

The presence of a new coronavirus spread unexpectedly around the world, triggering an unprecedented global crisis. By 2020, there were more than 7.9 million cases, and 434,796 deaths, in more than 200 countries. At that time, isolation and social distancing measures were implemented around the world to contain the accelerated spread of covid-19; Among the consequences, dental clinics were temporarily closed, and elective dental care was suspended, which led to an increase in the development of oral diseases. In relation to children and young people, there was an increase in this type of illness. The children were forced to spend most of their time at home with the acquisition of incorrect eating habits, intake of soft drinks and energy drinks that, in addition to containing high amounts of sugar, their acid content produces dental erosion and makes the enamel tissue less resistant to attack by cariogenic bacteria. In this work, a population of 96 school-age children was analyzed during a two-year period from 2020 to 2022. The results showed that 100% of the schoolchildren had dental caries at the time of their evaluation in January 2022, while 47% of the total had filled teeth and 64% of the total cases lost some of their teeth. These results are possibly due to the lack of knowledge of schoolchildren about hygiene for the prevention of dental caries and its consequences, the most damaging being the premature loss of temporary teeth, which makes it necessary to implement programs on promotion and prevention in the oral health in schoolchildren, teachers, and parents and representatives(AU)

Assessing knowledge of herbal medicine course for dental students.

BACKGROUND: The aims of this article are to assess dental students' knowledge about herbal medicine usage and the potential benefits and side effects, and to conduct a short course about herbal medicine. METHODS: All fourth-year pre-doctoral students were invited to participate in a herbal medicine course as a test while the sixth-year students were the control group. A survey was tested for validity and reliability. It comprised of 16 multiple choice questions was given before the course and one month after the course. The sum score of knowledge for each participant was calcuated based on the ability to identify the use of herbs in dentistry with high-quality evidence (correct answer) or total answer for periodontal disease and caries. RESULTS: The response rate for completing the study was 112 fourth-year students (73.7%) and 64 sixth-year students (39.0%). More than half of the participants (52.5%) were unsure about the importance of herbal medicine in dentistry. However, the majority also stated that the most common herbs used in dentistry were clove (62.9%), followed by curcuma turmeric (54.7%) and meswak (43.0%). The fourth-year students displayed evidence of a higher overall knowledge score after the course in herbal medicine related to periodontal disease in total and correct answers (mean 4.48 ± 4.13, 3.73 ± 3.31, respectively) compared to before the course (mean 0.84 ± 1.23, 0.74 ± 1.16, respectively) (p-value < 0.001). The post-course periodontal disease total and correct answers were statistically significant between fourth- and sixth-year students. CONCLUSION: Herbal medicine has a potential positive impact on dentistry. However, these effects are not fully investigated and received full attention in academic institute. This short educational program related to medicinal herbs can improve the knowledge of dental students. This will help increase the awareness about the use and potential side effects of herbal medicine in the dental field.

SARS-CoV-2 RNA in dental biofilms: Supragingival and subgingival findings from inpatients in a COVID-19 intensive care unit.

BACKGROUND: Saliva, salivary glands, gingival crevicular fluid, and supragingival biofilms may harbor SARS-CoV-2 RNA. This observational study aimed to investigate the presence and load of SARS-CoV-2 RNA in supragingival, and subgingival biofilms obtained from intensive care unit (ICU) patients. METHODS: A convenience sample, composed of 52 COVID-19+ participants (48.6 ± 14.8 years, 26.9% females), were evaluated for pre-existing comorbidities, number of teeth, and periodontal data [visible plaque (VPI), bleeding on probing (BOP), periodontal probing depth (PPD), and attachment loss (AL)]. Supragingival and subgingival samples (SubDeep: four sites with the deepest PPD; SubRemain: remaining shallower sites) were analyzed by RT-qPCR with corresponding cycle quantification (Cq). Statistical analyses considered the individual (P = 5%). RESULTS: Twenty-six participants tested positive for dental biofilms (Biofilm+) with 96.2% of them being positive for subgingival samples. Pre-existing comorbidities, number of teeth examined, VPI, PPD, AL, and BOP were similar between Biofilm+ and Biofilm-. SubDeep PPD (3.72 ± 0.86), AL (4.34 ± 1.33), and % of BOP (66.0 ± 31.1) values were significantly greater compared to SubRemain values (2.84 ± 0.48, 3.37 ± 0.34, and 20.4 ± 24.1, respectively). Biofilm+ Cqs showed no association with the periodontal condition. Cqs from Nasopharynx/Oropharynx (Naso/Oro; n = 36) were similar between Biofilm+ and Biofilm- participants. Length of time since ICU intake, last Naso/Oro RT-qPCR readings, onset of COVID-19 symptoms, and biofilm samplings were greater for Biofilm-. CONCLUSIONS: ICU patients harbored SARS-CoV-2 RNA in supragingival and subgingival biofilms, irrespective of the periodontal condition, and systemic viral load. The high number of positive patients highlights the need to better understand this habit to provide adequate oral care.

Self-Reported Periodontal Disease and Its Association with SARS-CoV-2 Infection.

Introduction: Knowledge of the oral manifestations associated with SARS-CoV-2 infection, the new coronavirus causing the COVID-19 pandemic, was hindered due to the restrictions issued to avoid proximity between people and to stop the rapid spread of the disease, which ultimately results in a hyperinflammatory cytokine storm that can cause death. Because periodontal disease is one of the most frequent inflammatory diseases of the oral cavity, various theories have emerged postulating periodontal disease as a risk factor for developing severe complications associated with COVID-19. This motivated various studies to integrate questions related to periodontal status. For the present work, we used a previously validated self-report, which is a useful tool for facilitating epidemiological studies of periodontal disease on a large scale. Methodology: A blinded case-control study with participants matched 1:1 by mean age (37.7 years), sex, tobacco habits and diseases was conducted. After the diagnostic samples for SARS-CoV-2 detection were taken in an ad hoc location at Guadalajara University, the subjects were interviewed using structured questionnaires to gather demographic, epidemiological and COVID-19 symptom information. The self-reported periodontal disease (Self-RPD) questionnaire included six questions, and subjects who met the criteria with a score ≥ 2 were considered to have periodontal disease. Results: In total, 369 participants were recruited, with 117 participants included in each group. After indicating the subjects who had self-reported periodontal disease, a statistically significant difference (p value ≤ 0.001) was observed, showing that self-reported periodontal disease (n = 95, 85.1%) was higher in SARS-CoV-2-positive individuals than in controls (n = 66, 56.4%), with an OR of 3.3 (1.8-6.0) for SARS-CoV-2 infection in people with self-reported periodontal disease. Cases reported a statistically higher median of symptoms (median = 7.0, Q1= 5.5, Q3 = 10.0) than controls (p value ≤ 0.01), and cases with positive self-RPD had a significantly (p value ≤ 0.05) higher number of symptoms (median = 8.0, Q1 = 6.0, Q3 = 10.0) in comparison with those who did negative self-RPD (median = 6.0, Q1 = 5.0, Q3 = 8.0). Conclusions: According to this study, self-reported periodontal disease could be considered a risk factor for SARS-CoV-2 infection, and these individuals present more symptoms.

Validation of a noninvasive aMMP-8 point-of-care diagnostic methodology in COVID-19 patients with periodontal disease.

OBJECTIVES: The aim of this study was to validate an active matrix metalloproteinase (MMP-8) point-of-care diagnostic tool in COVID-19 patients with periodontal disease. SUBJECTS, MATERIALS, AND METHODS: Seventy-two COVID-19-positive and 30 COVID-19-negative subjects were enrolled in the study. Demographic data were recorded, periodontal examination carried out, and chairside tests run for evaluating the expression of active MMP-8 (aMMP-8) in the site with maximum periodontal breakdown via gingival crevicular fluid sampling as well as via a mouth rinse-based kit for general disease activity. In COVID-19-positive patients, the kits were run again once the patients turned COVID-19 negative. RESULTS: The overall (n = 102) sensitivity/specificity of the mouthrinse-based kits to detect periodontal disease was 79.41%/36.76% and that of site-specific kits was 64.71%/55.88% while adjusting for age, gender, and smoking status increased the sensitivity and specificity (82.35%/76.47% and 73.53%/88.24, respectively). Receiver operating characteristic (ROC) analysis for the adjusted model revealed very good area under the ROC curve 0.746-0.869 (p < .001) and 0.740-0.872 (p < .001) (the aMMP-8 mouth rinse and site-specific kits, respectively). No statistically significant difference was observed in the distribution of results of aMMP-8 mouth rinse test (p = .302) and aMMP-8 site-specific test (p = .189) once the subjects recovered from COVID-19. CONCLUSIONS: The findings of the present study support the aMMP-8 point-of-care testing (PoCT) kits as screening tools for periodontitis in COVID-19 patients. The overall screening accuracy can be further increased by utilizing adjunctively risk factors of periodontitis. The reported noninvasive, user-friendly, and objective PoCT diagnostic methodology may provide a way of stratifying risk groups, deciding upon referrals, and in the institution of diligent oral hygiene regimens.

Effectiveness and Clinical Performance of Erythritol Air-Polishing in Non-Surgical Periodontal Therapy: A Systematic Review of Randomized Clinical Trials.

Background and objectives: The purpose of the present systematic review was to analyze the effectiveness of erythritol-based air-polishing in non-surgical periodontal therapy. Materials and methods: The protocol details were registered in the PROSPERO database (CRD42021267261). This review was conducted under the PRISMA guidelines. The electronic search was performed in PubMed, Scopus, and Web of Science databases to find relevant clinical trials published until January 2022. The inclusion criteria consisted of human clinical trials which reported the use of non-surgical periodontal treatment and erythritol air-polishing compared to non-surgical periodontal treatment alone in patients with good systemic health requiring treatment for periodontal disease. Results: 810 studies were imported into the Covidence Platform. Of these, seven clinical trials met the inclusion criteria. In active periodontal therapy, for PD (probing depth), CAL (clinical attachment level), and BOP (bleeding on probing), no statistical significance was achieved at 6 months follow-up. In supportive periodontal therapy for PD, CAL, and BOP, no statistical significance was achieved at 3 months follow-up. Conclusions: The findings suggest that erythritol air-polishing powder did not determine superior improvements of periodontal parameters compared to other non-surgical periodontal therapies. Future randomized clinical trials (RCTs) with calibrated protocols for diagnosis, therapeutic approaches, and longer follow-up are needed to draw a clear conclusion about the efficiency of erythritol air-polishing powder.

A Cross-Sectional Survey on the Association between Dental Health Conditions and University Personality Inventory Scores among University Students: A Single-Center Study in Japan.

This study examined the association between dental health conditions and scores on the University Personality Inventory (UPI) among university students in Japan. Participants were freshmen at Yamagata University between 2010 and 2019. Dental check-ups, including dental caries, periodontal disease, malocclusion, and temporomandibular disorders (TMD), and mental health screening using the UPI were performed; 12,433 students were included in the final analysis. A logistic regression analysis was performed to confirm the association between dental health conditions and >30 UPI scores, which indicate the need to consult mental health professionals. Overall, students who required treatment for TMD had a 3.165-fold higher risk of >30 UPI scores (OR = 3.165, 95% CI = 1.710-5.857). Periodontal disease and TMD in male participants (periodontal disease: OR = 1.329, 95% CI = 1.108-1.595; TMD: OR = 3.014, 95% CI = 1.107-8.204) and TMD in female participants (OR = 2.938, 95% CI = 1.340-6.445) were significant risk factors for >30 UPI scores. Students requiring treatment for TMD were at risk of obtaining >30 UPI scores. Although our study has several limitations, students with subjective symptoms (e.g., disturbance in opening the mouth) should take the UPI test or in some cases consult mental health professionals.

Probiotics and dairy products in dentistry: A bibliometric and critical review of randomized clinical trials.

The oral environment is an essential part of the human microbiome. The consumption of probiotic products may improve the oral microbiota and reduce the risk of diseases. This paper presents a bibliometric and critical review of randomized clinical trials (RCTs) that used probiotics to analyze oral parameters in humans. RCTs carried out with no age, gender, and ethnicity restrictions and published in the pre-COVID-19 period were included. Furthermore, the utilization of probiotic dairy products to improve oral health is discussed. The bibliometric review demonstrated that 'Microbiology,' 'Dental caries,' and 'Streptococcus mutants' were the most highlighted keywords. Furthermore, Sweden and India have the highest number of publications. The most prevalent outcomes were 'salivary parameters,' 'periodontal disease,' and 'dental caries.' The most used vehicles for probiotic administration were pharmaceutical formulas and dairy products. The administration of probiotic dairy products could modify the oral microbiota (reductions in S. mutans counts), influence the caries development and periodontal disease in children, adolescents, adults, and the elderly, and improve gingival health. The main probiotic dairy products investigated were milk, fermented milk, yogurt, kefir, curd, and cheese. Lacticaseibacillus paracasei SD1 was the most used probiotic culture. The studies demonstrated that the probiotic effect lasted 2-4 weeks after discontinuing consumption. However, the results depended on the subject type, study design, probiotic strain and concentration, and dairy product type. In conclusion, probiotic dairy products are promising alternatives to improve oral health.

Interconnection of periodontal disease and comorbidities: Evidence, mechanisms, and implications.

Periodontitis, a microbiome-driven inflammatory disease of the tooth-attachment apparatus, is epidemiologically linked with other disorders, including cardio-metabolic, cognitive neurodegenerative and autoimmune diseases, respiratory infections, and certain cancers. These associations may, in part, be causal, as suggested by interventional studies showing that local treatment of periodontitis reduces systemic inflammation and surrogate markers of comorbid diseases. The potential cause-and-effect connection between periodontitis and comorbidities is corroborated by studies in preclinical models of disease, which additionally provided mechanistic insights into these associations. This overview discusses recent advances in our understanding of the periodontitis-systemic disease connection, which may potentially lead to innovative therapeutic options to reduce the risk of periodontitis-linked comorbidities.

Periodontal disease increases the host susceptibility to COVID-19 and its severity: a Mendelian randomization study.

BACKGROUND: Emerging evidence shows that periodontal disease (PD) may increase the risk of Coronavirus disease 2019 (COVID-19) complications. Here, we undertook a two-sample Mendelian randomization (MR) study, and investigated for the first time the possible causal impact of PD on host susceptibility to COVID-19 and its severity. METHODS: Summary statistics of COVID-19 susceptibility and severity were retrieved from the COVID-19 Host Genetics Initiative and used as outcomes. Single nucleotide polymorphisms associated with PD in Genome-wide association study were included as exposure. Inverse-variance weighted (IVW) method was employed as the main approach to analyze the causal relationships between PD and COVID-19. Three additional methods were adopted, allowing the existence of horizontal pleiotropy, including MR-Egger regression, weighted median and weighted mode methods. Comprehensive sensitivity analyses were also conducted for estimating the robustness of the identified associations. RESULTS: The MR estimates showed that PD was significantly associated with significantly higher susceptibility to COVID-19 using IVW (OR = 1.024, P = 0.017, 95% CI 1.004-1.045) and weighted median method (OR = 1.029, P = 0.024, 95% CI 1.003-1.055). Furthermore, it revealed that PD was significantly linked to COVID-19 severity based on the comparison of hospitalization versus population controls (IVW, OR = 1.025, P = 0.039, 95% CI 1.001-1.049; weighted median, OR = 1.030, P = 0.027, 95% CI 1.003-1.058). No such association was observed in the cohort of highly severe cases confirmed versus those not hospitalized due to COVID-19. CONCLUSIONS: We provide evidence on the possible causality of PD accounting for the susceptibility and severity of COVID-19, highlighting the importance of oral/periodontal healthcare for general wellbeing during the pandemic and beyond.