Aphthous stomatitis near to the ulcer, described histologically as "perivascular cuffing". Aphthous stomatitis has been classified as a type of non-infectious stomatitis (inflammation of the mouth). One classification distinguishes "common simple aphthae", accounting for 95% of cases, with 3–6 attacks per year, rapid healing, minimal pain and restriction of ulceration to the mouth; and "complex aphthae", accounting for 5% of cases, where ulcers may be present on the genital mucosa in addition to mouth, healing is slower and pain is more severe. A more common method of classifying aphthous stomatitis is into three variants, distinguished by the size, number and location of
Denture-related stomatitis denture-related stomatitis. Poorly fitting dentures may cause pressure on the mucosa and mechanical irritation may create a similar clinical appearance, but this is uncommon. An orthodontic appliance may uncommonly produce a similar result. However, mucosal trauma is thought increase the ability of "C. albicans" to invade the tissues. Aside from infection and mechanical trauma, inflammatory reactions of the mucosa beneath a denture can also result from irritation or allergy (allergic contact stomatitis) caused by the materials in the denture itself (acrylic, cobalt, chromium), or in response to substances within denture adhesives. Incomplete curing of the acrylic resin (the prosthetic material)