Oral expression following COVID-19: A systematic review

Abstract

Objective: The aim of this study was to systematically review the literature to gather the oral manifestations of coronavirus disease-2019 (Covid-19), evaluate a direct accountability for severe acute respiratory syndrome-coronavirus 2 (SARS-Cov2), and determine a correlation between ACE2 receptor oral tissue density and Covid-19 lesions. Materials and Methods: PubMed and Web of Science were searched from January 2020 to April 2022; the principal outcome was oral manifestations in PCR-tested patients positive for Covid-19. PRISMA protocol was used to evaluate the results. Results: Among the 535 articles reviewed, 80 were included and analyzed. Oral ulcerations were found most frequently as dermatologic lesions, followed by erythema and macules (as a harbinger or not of ulcerations). Direct accountability was difficult to establish because of the systemic proinflammatory stimulation following Covid-19. Lesion topography was essentially lingual and palatal according to an ACE2 high-density tissue level and recent histologic evidence of SARS-Cov2 presence in the lesions. A direct inflammation of the salivary glands was also reported. Conclusion: Evidence to distinguish direct and indirect etiologies of the SARS-Cov2 virus following Covid-19 infection was poor. It could be deepened by investigating the presence of the SARS-Cov2 virus in tissue lesions and tissue disorders activated by ACE2 pathways.