Pathophysiology of oral lesions subsequent to SARS-CoV-2 vaccination: A systematic review

Amidst worldwide reports of adverse oral lesions subsequent to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination, the current systematic review planned to determine the prevalence of adverse oral events in adult individuals (≥18 years) after SARS-CoV-2 vaccination, emphasizing upon the type and dose of vaccine, time of onset, and underlying pathophysiology. The registered protocol (PROSPERO CRD42023421307), conforming with PRISMA guidelines, included an all-inclusive literature search through online databases, consisting of Scopus, PubMed/MEDLINE, Web of Science, Lilacs, Livivo, and PROSPERO, completed on 2 May 2023, followed by assessment of risk of bias by Joana Briggs Institute Evaluation Checklist. Due to the paucity of literature, case reports and case series were included. Self-reported lesions were excluded. Qualitative synthesis employing Microsoft Excel software 2019 revealed low prevalence (43 subjects) from 26 case reports and two case series. There were multiple erosive oral ulcers on gingiva, palate, burning pain in the mouth, xerostomia, tongue fissuring and glossitis, palatal petechiae, diffuse erythematous lesions and loss of smell (16.2%), primary herpetic gingivostomatitis (21%), oral lichen planus (16.2%), Stevens-Johnson syndrome (6.9%), Bell's palsy in four cases where two cases were Guillain-Barré syndrome (9.3%), erythema multiforme (11.6%), pemphigus (4.6%), idiopathic thrombocytopenic purpura (6.9%), unilateral hypoglossal nerve palsy (4.6%), and trigeminal neuralgia (2.3%). Maximum cases (22 subjects) presented oral lesions after Pfizer (BNT162b2) SARS-CoV-2 vaccine. No association was found between the vaccine type and dose with oral side effects. Dentists must be aware of the oral adverse effects after coronavirus disease 2019 vaccination to better understand the pathogenesis and the risk factors associated with such reactions.