Oral ulcers may result in congestion and swelling of the mucosa surrounding the lesion, as described below.
Recurrent Aphthous ulcers histologically appear as non-specific ulcers with fibrin exudate and neutrophilic infiltration visible on the surface, and inflammatory granulation tissue beneath, showing capillary and fibroblast proliferation and tissue edema.
Mild recurrent Aphthous ulcers begin as focal mucosal congestion and edema with cornified red spots, followed by the formation of superficial ulcers. Severe aphthous ulcers may be greater than ten millimeters in diameter, with erythema and micro-embryony of the surrounding tissue. Herpes-like recurrent Aphthous ulcers can be fused into adjacent ulcers, with congested mucous membranes that are swollen and red.
If any of these symptoms occur, it is recommended to visit a hospital promptly and receive early professional treatment.