What is the direct answer?
Swelling beneath one tooth can come from gum inflammation or a tooth-root infection and needs examination if it persists or worsens.
What does this question mean?
A tender bump beside a tooth may be an abscess, which is a collection of inflammatory fluid related to bacteria in the gum or inside the tooth. Plaque trapped under the gum, decay reaching the pulp, a cracked tooth or food wedged between teeth can produce similar swelling.
What can you do next?
Brush gently with fluoride toothpaste, clean between the teeth, and rinse with warm salt water if it is comfortable. Do not squeeze or puncture the swelling, place aspirin on the gum, or use leftover antibiotics; these actions can injure tissue or delay the correct treatment.
When should you seek dental care?
Arrange dental care promptly for a localized swelling, pus, bad taste, fever, increasing pain, or pain when biting. Seek urgent medical help if swelling spreads into the face or neck, or if breathing, swallowing, or opening the mouth becomes difficult.
What should you ask the dentist?
Ask whether the swelling is from the gum pocket, the tooth pulp, or a crack, and whether an X-ray is needed. Ask which treatment addresses the cause, such as professional cleaning, drainage, a root canal, or removal of a tooth that cannot be restored.
Frequently asked questions
Can a gum swelling disappear by itself?
It may drain and feel smaller while the underlying infection remains, so a disappearing bump does not prove the cause is resolved.
Will antibiotics fix the tooth?
Antibiotics may be used for spreading infection or systemic symptoms, but they do not remove infected pulp or repair a source tooth.

