Dental Nation
Question and answer

Back of teeth swollen

Swelling behind the back teeth can come from gum inflammation, a partially erupted wisdom tooth, food trapping, decay, or infection around a tooth.

The short answer

The tissue behind a back molar may be the gum over or around a partially erupted third molar, the cheek-side gum, or a swelling from the tooth root. Its location and appearance help narrow the cause.

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What is the direct answer?

What does this question mean?

Common causes include pericoronitis around a wisdom tooth, plaque-related gum inflammation, trapped food, decay, a cracked tooth, and an abscess. A tender lump can also arise from trauma or a blocked salivary structure.

What can you do next?

Rinse gently with warm water, keep the area clean with a small soft brush, and avoid squeezing the swelling or placing aspirin on the gum. Use only pain medicine that is suitable for you and follow its label.

When should you seek dental care?

Arrange dental care promptly for swelling that lasts, returns, causes pain, bad taste, fever, facial swelling, or limits opening. Emergency assessment is needed for trouble breathing or swallowing or rapidly spreading facial swelling.

What should you ask the dentist?

Ask whether a wisdom tooth, gum pocket, cavity, crack, or root infection is responsible. Ask whether cleaning, drainage, filling, root-canal treatment, or removal is indicated and what imaging shows.

Frequently asked questions

Can food cause this swelling?

Food trapped under a gum flap or between teeth can inflame tissue, but recurring swelling needs assessment for a deeper cause.

Should a swollen gum be popped?

No. Squeezing can injure tissue and spread contamination; dental treatment addresses the source instead.