Rear gum swollen
Swelling at the back of the gum commonly comes from an erupting or impacted wisdom tooth, food and plaque trapped under a gum flap, or infection in a ne.
The short answer
Swelling at the back of the gum commonly comes from an erupting or impacted wisdom tooth, food and plaque trapped under a gum flap, or infection in a nearby tooth.
What can a gum flap behind the molar indicate?
The tissue behind the second molar may form a flap over a partially erupted third molar. Bacteria and debris can collect beneath it, causing pericoronitis, while decay or pulp infection in a molar can create a separate abscess.
How can you care for swelling at the back of the gum?
Rinse gently with warm water, keep the area as clean as possible with a small soft brush, avoid poking the gum, and arrange an examination with appropriate dental imaging.
When does rear gum swelling need urgent dental care?
Seek same-day care for increasing facial swelling, fever, pus, severe pain, reduced mouth opening, or difficulty swallowing. Go to emergency services for breathing difficulty or swelling that is spreading quickly.
What should you ask about swelling near a wisdom tooth?
Ask whether the swelling is pericoronitis, a tooth abscess, gum disease, or trauma, whether the wisdom tooth can erupt normally, and whether cleaning, drainage, restoration, root canal treatment, or removal is indicated.
Frequently asked questions
Is a rear gum lump always a wisdom tooth?
No. It can also reflect an abscess, periodontal pocket, trauma, cyst, or another oral lesion, so its location and cause need examination.
Can I wait if the swelling is painless?
A painless swelling can still represent infection or another lesion; arrange a dental assessment rather than relying on pain as a guide.
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.