Bump on gum by wisdom tooth

A bump beside a wisdom tooth may be an eruption flap, inflamed gum, a cyst, or a dental infection needing examination.

Partly erupted wisdom teeth can leave a fold of gingiva called an operculum, where food and bacteria collect. Tender swelling can also arise from pericoronitis, decay in the wisdom tooth or adjacent molar, a periodontal pocket, or a fluid-filled lesion around an unerupted tooth.

Keep the area gently clean with a small soft brush and rinse with warm salt water if it is comfortable. Do not puncture the lump; a dentist may irrigate beneath the gum flap, treat decay or infection, and use an X-ray to decide whether monitoring or extraction is appropriate.

Book an examination if the bump lasts, recurs, bleeds, or makes chewing difficult. Same-day urgent care is needed for spreading facial swelling, fever, difficulty swallowing, or difficulty opening the mouth.

Ask whether the lump is an operculum, an abscess, a cyst, or another lesion and whether the neighboring molar is affected. Ask which radiograph is needed, whether the tooth has room to erupt, and what treatment would prevent another episode.