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.

Objectives: The aim of this study was to evaluate the relationship between systemic oxidative balance, and the severity of the disease in patients with COVID 19. Methods: Sixty-four patients were divided into three groups according to the severity of the disease: mild (n=28), moderate (n=11) and severe (n=25). Twenty-four healthy controls included to the study. Proinflammatory cytokines (IL-6 and TNF-α), D-dimer, fibrinogen, total oxidative status (TOS), total antioxidant status (TAS) were measured and oxidative stress index (OSI) was calculated. Results: The mean age of severe group was significantly higher than the other groups (p=0.001). TAS levels were significantly decreased in all patient groups compared to controls, while serum TOS and OSI levels were significantly different in all three stages of the disease. Serum IL-6 and TNF- α levels were significantly elevated in severe group compared to other groups. TOS and OSI levels were also significantly correlated with IL-6, CRP, ferritin, fibrinogen, LDH and D-dimer. Conclusions: TOS and OSI levels are an indicator of systemic oxidative balance in COVID-19 and related to the disease severity. They can be an important marker for evaluating the disease severity and used in the management of patients with COVID-19.

Background: To emphasize the importance of CT in the diagnosis of COVID-19 disease by comparing the thoracic CT findings of COVID-19 patients with positive RT-PCR results and patients with clinical suspicion of COVID-19 but with negative RT-PCR results. Results: In our study, COVID-19 patients with positive RT-PCR results (RT-PCR (+) group) and patients with clinical suspicion of COVID-19 but negative RT-PCR results (RT-PCR (−) group) were compared in terms of CT findings. In CT images, ground-glass opacity and ground-glass opacity + patchy consolidation were the most common lesion patterns in both groups. No statistically significant differences in the rates and types of lesion patterns were observed between the two groups. In both groups, lesion distributions and distribution patterns were similarly frequent in the bilateral, peripheral, and lower lobe distributions. Among the 39 patients who underwent follow-up CT imaging in the first or second month, a regression in lesion number and density was detected in 18 patients from both groups. Consolidations were completely resorbed in 16 of these patients, and five patients had newly developed fibrotic changes. The follow-up CT examination of 16 patients was normal. Conclusions: Due to the false-negative rate of RT-PCR tests caused by various reasons, clinically suspected COVID-19 patients with a contact history should be examined with CT scans, even if RT-PCR tests are negative. If the CT findings are positive, these patients should not be removed from isolation.