Reports & Studies

Covid-19 & oral symptoms

PD Dr. Kristina Bertl, PhD MSc MBA

According to data from the World Health Organization (WHO), almost 110,000,000 people have tested positive for Covid-19 since the pandemic began in December 2019, and 2,435,000 of these cases have had a fatal outcome. On account of this huge outbreak, our professional and social lives have also changed over the past twelve months, in some cases massively.

Scientific interest in SARS-CoV-2 has been similarly huge, and the number of scientific publications on this subject has virtually exploded since the pandemic broke out. What is dentistry’s contribution to this field at present? Two very interesting publications on Covid-19 have already appeared in 2021: a systematic review about manifestations of oral symptoms in patients with Covid-19 (Amorim dos Santos et al. 2021) and a case-control study of how periodontitis affects the course of a Covid-19 infection (Marouf et al. 2021).

In this article we concentrate on the systematic review about manifestations of oral symptoms in patients with Covid-19 (Amorim dos Santos et al. 2021). The authors of this study analyzed the data from 40 publications involving more than 10,000 Covid-19 cases. The most common oral symptom by far was an impaired of sense of taste, which occurred in almost half of those infected. Of these patients, 38% reported an altered sense of taste, 35% a weakening of their sense of taste, and 24% a complete loss of sense of taste.

In terms of oral lesions, the symptoms were unfortunately substantially less specific. Patients described both white and red patches, ulcers, blisters and petechiae on the tongue, palate, lips, gingivae and cheeks. These symptoms were observed both before and up to several days after the appearance of other, more clear-cut symptoms. Accordingly, it is assumed that oral lesions in patients with a Covid-19 infection are more likely to be a secondary infection, secondary manifestations and/or manifestations related to the strain on the immune system, with a wide clinical presentation.

In summary, an altered sense of taste is a very distinctive feature, but the possibility of detecting a Covid-19 infection on the basis of oral lesions is rather unlikely.


  1. Amorim dos Santos J, Normando AGC, Carvalho da Silva RL, et al. Oral Manifestations in Patients with COVID-19: A Living Systematic Review. Journal of Dental Research. 2021, Vol. 100(2): 141–154.
    Marouf N, Cai W, Said KN, et al. Association between periodontitis and severity of COVID-19 infection: A case-control study. J Clin Periodontol. 2021;00: 1–9.