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.