What is the direct answer?
Gums swollen behind teeth may reflect plaque-related gingivitis, food impaction, a partially erupted wisdom tooth, trauma, or infection near a tooth.
What does this question mean?
Gum behind a molar can trap plaque and food, especially around a partly erupted third molar. Inflammation may cause tenderness, bad taste, pus, or spreading swelling.
What can you do next?
Clean gently with a soft brush and rinse with warm salt water. Do not poke, squeeze, or put aspirin on the gum; an examination may include imaging.
When should you seek dental care?
Facial swelling, fever, pus, limited mouth opening, or swallowing difficulty needs urgent care.
What should you ask the dentist?
Ask whether the cause is gum inflammation, food trapping, a wisdom tooth, or a tooth infection.
Frequently asked questions
Can home care identify the cause?
Home care may reduce irritation, but an examination is needed when symptoms persist.
What should you record?
Note when it began, triggers, products used, and any swelling, bleeding, fever, or visible change.

