Background: Research suggests that periodontal disease may exacerbate symptoms of coronavirus disease (COVID-19). The etiology of this condition has been associated with cytokines such as IL-6. The inflammatory response in COVID-19 can be partially attributed to periodontopathic bacteria and their metabolites. Furthermore, the aspiration of periodontal pathogens and the stimulation of ACE2 expression may lead to an increased production of inflammatory cytokines, potentially worsening COVID-19 symptoms in patients with periodontitis. Materials and Methods: A cross-sectional study was conducted involving patients with both periodontal disease and COVID-19, patients with either condition alone, and healthy subjects. All participants underwent RT-PCR testing for SARS-CoV-2, and a self-reported periodontal disease (Self-RPD) questionnaire was administered. Saliva samples were collected to assess IL-6 levels using the ELISA technique. Results: A total of 28 patients were classified as COVID-19/Self-RPD+, 32 patients had only COVID-19, 25 were Self-RPD+ only, and 17 were healthy controls. The COVID-19/Self-RPD+ group frequently exhibited symptoms such as fever, body aches, nasal congestion, and olfactory disturbances and showed significantly higher IL-6 levels compared to the other groups. Cough with phlegm was significantly more frequent in the COVID-19-only group. Additionally, IL-6 levels in saliva were elevated in patients with nasal congestion and in those with 11 or more symptoms in the Self-RPD+ group.