Aphthous stomatitis stomatitis may show herpes virus within the epithelium of the mucosa, but without any productive infection. In some persons, attacks of ulceration occur at the same time as asymptomatic viral shedding and elevated viral titres. In some instances, recurrent mouth ulcers may be a manifestation of an allergic reaction. Possible allergens include certain foods ("e.g.", chocolate, coffee, strawberries, eggs, nuts, tomatoes, cheese, citrus fruits, benzoates, cinnamaldehyde, and highly acidic foods), toothpastes, and mouthwashes. Where dietary allergens are responsible, mouth ulcers usually develop within about 12–24 hours of exposure. Sodium lauryl sulphate (SLS), a detergent present in some brands of toothpaste
Supernumerary body part considered to have lost much or all of their original function through evolution. These body parts can be classed as additional to the required functioning of the body. In human anatomy the vermiform appendix is sometimes classed as a vestigial remnant. Prosthesis is an artificial extension that replaces a body part, and cybernetics is the study of computer technology in relation to organisms which can include replacement or additional body parts. Body integrity identity disorder (BIID) is a psychiatric disorder in which a person thinks that they have one or more additional limbs than they should, despite having two arms