Covid-19 and SARS-CoV-2 infection in periodontology: A narrative review

The present review examined the available evidence on possible involvement of gingival tissues in SARS-CoV-2 infection. Gingival tissue possess SARS-CoV-2 entry and transmission factors, among them ACE2 (angiotensin-converting enzyme 2) and TMPRSS2 (transmembrane protease serine 2), which are the principal mediators of the virus cell invasion. Clinical observations reveal SARS-CoV-2 RNA in periodontal tissues and crevicular fluid, suggesting that the periodontium may act as an entry point for the virus and/or as a dissemination site. The preliminary observations prove infection potential of gingival crevicular fluid and shed epithelial cells from the periodontium. There are also findings on potential associations between periodontitis and Covid-19 (coronavirus disease 2019). PubMed and Scopus databases were used to search for suitable keywords such as: SARS-CoV-2, Covid-19, oral virus infection, gingival crevicular fluid, oral mucosa, periodontium, gingiva, ACE2, TMPRSS2, Furin, diagnosis, topical treatment, vaccine and the related words for relevant publications. Data extraction and quality valuation of articles were performed by the author. The review addressed seven major domains: periodontal structures as SARS-CoV-2 infection site, the periodontal changes under SARS-CoV-2 infection, potential associations between periodontitis and Covid-19, periodontal oral care in Covid-19, crevicular fluid as potential transmission factor and preventive measures. The search process in PubMed and Scopus was updated up to 31 March 2022. Finally 68 articles were retrieved for the final analysis, from the initial database searches. According to the inclusion criteria articles in English language without any date restriction were included. The included studies were mostly original articles, and published in 2020 and 2021 with the aim to describe Covid-19 and SARS-CoV-2 infection in periodontology. As a conclusion it can be stated that gingival tissues may play a role in SARS-CoV-2 infection.