“… 4 , 5 , 6 According to the associated studies, the most frequent oral finding was oral ulceration, and there were distinct clinical patterns observed in different case studies. 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 Despite growing literatures investigating oral presentations in COVID-19 patients, few of them provide deep insight into oral ulcerative lesions, the most frequent but diverse one. The detailed clinical features, histological findings, immune profile, and the possible underlying pathogenetic mechanism of the oral ulcerative lesions are still lacking.…”