A painful bump on the roof of the mouth may be an ulcer that developed from extra bone, called a mandibular torus or exostosis, bumping against hard foods, explains 1st Impressions Dental Practice. It may also be a fever blister, notes the American Academy of Otolaryngology–Head and Neck Surgery.
Fever blisters occur most often on the lips, but they can also appear on the roof of the mouth or gums in rare cases, explains the American Academy of Otolaryngology–Head and Neck Surgery. They last about seven to 10 days and form when the herpes simple virus, which is usually in its dormant state, becomes activated by circumstances such as stress, hormonal fluctuations or fever. Within hours of appearing, the fever blister ruptures and forms a crust.
All people have a bump called an incisive papilla on the roof of their mouths behind their front teeth, explains 1st Impressions Dental Practice. Although this bump is a normal part of human anatomy, it is possible for it to become irritated and enlarged, which may lead people to think they have an abnormal bump on the roof of their mouths. Temporary irritation is not cause for concern, but enlargement may warrant treatment by a dentist or oral pathologist.