What is the direct answer?
A small blister above a tooth can be a draining dental abscess, an ulcer, or irritated tissue; its appearance alone cannot identify the cause.
What does this question mean?
A gum boil or parulis may form when infection from the pulp or root tip drains through bone into the gum. Other possibilities include a traumatic ulcer, blocked minor salivary tissue, or a local reaction, especially when no tooth pain is present.
What can you do next?
Do not squeeze, pierce, or burn the blister. Keep the area clean with gentle brushing and arrange an examination; the dentist may test the tooth, take an X-ray, drain infection when indicated, and treat the source.
When should you seek dental care?
Seek prompt dental care if it is painful, recurrent, enlarging, or accompanied by bad taste, pus, fever, swelling, or a tooth that is tender to biting. Facial swelling or difficulty breathing or swallowing is urgent.
What should you ask the dentist?
Ask whether the nearby tooth responds normally, whether an X-ray is needed, and whether the cause is an abscess requiring root-canal treatment, extraction, or another form of care.
Frequently asked questions
Can this be diagnosed from appearance alone?
No. A dental examination may include focused tests or imaging to identify the cause.
What should I avoid doing at home?
Avoid squeezing, scraping, or applying unprescribed chemicals to the affected teeth or gums.

