Role of viruses in periodontitis: An extensive review of herpesviruses, human immunodeficiency virus, coronavirus-19, papillomavirus and hepatitis viruses

Abstract

Periodontitis is the inflammation of the supporting structures around the dentition. Several microbial agents, mostly bacteria, have been identified as causative factors for periodontal disease. On the other hand, oral cavity is a rich reservoir for viruses since it contains a wide variety of cell types that can be targeted by viruses. Traditionally, the focus of research about the oral flora has been on bacteria because the most widespread oral diseases, like periodontitis and dental caries, are outcomes of bacterial infection. However, recently and especially after the emergence of coronavirus disease 2019, there is a growing tendency toward including viruses also into the scope of oral microbiome investigations. The global high prevalence of periodontitis and viral infections may point out to a concomitant or synergistic effect between the two. Although the exact nature of the mechanism still is not clearly understood, this could be speculated through the manipulation of the immune system by viruses; hence facilitating the furthermore colonization of the oral tissues by bacteria. This review provides an extensive and detailed update on the role of the most common viruses including herpes family (herpes simplex, varicella-zoster, Epstein-Barr, cytomegalovirus), Human papillomaviruses, Human immunodeficiency virus and severe acute respiratory syndrome coronavirus 2 in the initiation, progression and prognosis of periodontitis.

Keywords: Bacteria; Cytomegalovirus; Epstein-Barr virus; Herpes simplex virus; Herpesvirus; Human immunodeficiency virus; Human papillomaviruses; Periodontitis; SARS-CoV-2; Varicella-zoster virus; Virus.

Figure 1

Possible mechanisms of interaction between periodontitis and coronavirus disease 2019 infection. (1) Periodontal pocket act like a reservoir for severe acute respiratory syndrome coronavirus 2 and an entrance into the blood stream; (2) Periodontitis as a source for increased direct inoculation of periodontopathic bacteria into the respiratory system in coronavirus disease 2019 (COVID-19) patients; and (3) Periodontitis as a source for increased systemic inflammation and priming the immune system in COVID-19 patients. (Created at BioRender.com)