Xerostomia in COVID-19 and other oral diseases: a review

Relevance . In recent years, there has been a growing number of scientific studies addressing various oral changes observed in patients who have recovered from COVID-19. Research examining the consequences of coronavirus infection in dental practice demonstrates a wide spectrum of manifestations, including erosive lesions of the oral mucosa, aphthous ulcerations, and vesicular elements. In addition to inadequate oral hygiene and the presence of chronic dental diseases, xerostomia syndrome represents an aggravating factor that may exacerbate oral inflammatory conditions. Objective. To analyze published studies assessing the occurrence of xerostomia in COVID-19 and its association with other oral diseases. Materials and methods . A qualitative analysis of scientific sources focusing on xerostomia in COVID-19 and its relationship with other oral diseases was conducted. Literature searches were performed in the PubMed, Scopus, Web of Science, eLibrary.ru, and Google Scholar databases using relevant Russian and English keywords, including “COVID-19,” “SARS-CoV-2,” “xerostomia,” “dry mouth,” “hyposalivation,” “salivary glands,” and “oral diseases.” The review included original research articles and narrative reviews published in Russian and English over the past seven years. Duplicate records, publications without full-text availability, and studies with low methodological quality were excluded. Study selection was carried out based on titles and abstracts, followed by full-text assessment. Results. Based on studies conducted by Russian and international researchers, oral mucosal lesions associated with SARS-CoV-2 infection, as well as with other oral diseases, have been shown to contribute to the development of xerostomia, dry mouth, and hyposalivation. These conditions may aggravate the course of oral diseases, promote oral dysbiosis, and increase the risk of secondary infections. The observed changes are presumed to result from both direct and indirect effects of the virus on oral cavity cells, as well as from concomitant infections, immune suppression, and adverse pharmacological effects. Particular attention should be paid to xerostomia, dry mouth, and hyposalivation in patients with COVID-19 and other oral diseases. Conclusion. Oral mucosal lesions and the development of xerostomia in infections caused by SARS-CoV-2, as well as in other oral diseases, may be attributed to both the direct effects of the virus on oral cavity cells and indirect mechanisms associated with concomitant infections, immune suppression, and pharmacological factors.