Gum swollen at back of mouth
Swelling behind the last molar can come from an erupting wisdom tooth, trapped food, gum disease or a dental infection.
Why is the gum swollen at the back of your mouth?
Swelling behind the last molar can come from an erupting wisdom tooth, trapped food, gum disease or a dental infection.
What is the gum flap behind the last molar?
The area may be the gum over a partially erupted third molar, called a pericoronal flap. Bacteria and food can collect beneath it, while a cavity, gum pocket or infection at the tooth root can also enlarge nearby tissue.
How can you clean swelling behind the last molar?
Gently clean the back molar with a soft brush and rinse with warm salt water without forcing anything under the gum. Choose softer foods, avoid smoking, and do not squeeze the swelling or place chemicals on it.
When should back-of-mouth swelling be examined?
Book an examination if swelling lasts, recurs, bleeds, produces a bad taste, or makes chewing difficult. Get urgent help if it spreads into the cheek or neck, or causes fever, difficulty swallowing, breathing difficulty or restricted mouth opening.
Could a wisdom tooth be causing the swelling?
Ask whether the wisdom tooth is erupting normally and whether an examination or panoramic radiograph is needed. Ask if cleaning, gum treatment, restoration, extraction or another procedure addresses the identified cause.
Frequently asked questions
Can a swollen gum behind a molar settle by itself?
Minor irritation may settle after cleaning, but repeated or persistent swelling needs assessment because the tooth or gum may require treatment.
Does swelling always mean a wisdom tooth must be removed?
No. The decision depends on the tooth position, symptoms, cleaning access and findings on examination and imaging.
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Who wrote this page
This library is published by Dental Nation, a licensed dental group practising in the United Arab Emirates. Pages are written and overseen by the same clinical team that treats patients in our clinics, and are held to a fixed editorial standard for safety and accuracy.
This page is patient education, not medical advice, and cannot replace an examination. Anything urgent — facial swelling, trauma, uncontrolled bleeding or severe pain — needs a dentist or emergency care now.