Sudden pain behind the back molars, a sore throat when swallowing, facial swelling, or difficulty opening the mouth often raises the question of wisdom-tooth eruption or inflammation. This page focuses on recognising symptoms (especially throat pain on swallowing, bad breath, and limited mouth opening) and when to see a dentist promptly. For gum swelling, general wisdom-tooth pain, and treatment steps, see Causes of Wisdom Tooth Swelling and Pain.
Common wisdom-tooth inflammation symptoms
- Sore throat / pain on swallowing: when inflammation sits near the throat, swallowing can pull on the sore area — it can feel like a cold, but the source is behind the back molar.
- Facial swelling and toothache: cheek or jaw swelling that is tender to touch; red, swollen gum behind the molar is also common.
- Difficulty opening the mouth: a tight jaw and a smaller opening that makes eating and cleaning harder.
- Bad breath or pus: a gum flap traps food debris; bacteria can cause odour or discharge.
- Fever or swollen lymph nodes: a sign the inflammation may be worsening — do not wait.
Why this happens (briefly)
When there is not enough space, a wisdom tooth may erupt at an angle or stay impacted, making cleaning difficult. Trapped food then inflames the gum around the crown (pericoronitis). For general swelling, pain checklists and treatment steps, see Causes of Wisdom Tooth Swelling and Pain.
When to see a dentist promptly
- Severe pain that keeps returning after painkillers
- Ongoing facial swelling, limited opening, or difficulty swallowing
- Fever or tender lymph nodes
- Pus or clearly worsening breath odour
Seek care promptly to reduce the risk of a more serious infection. Treatment is provided at our Causeway Bay and Tsuen Wan centres.
What you can try first (relief only — not a substitute for care)
Rinse gently with saline and clean carefully behind the back molar. If there is no improvement or any warning sign above appears, do not delay. Full urgent and longer-term options (including non-surgical or surgical removal) are in Causes of Wisdom Tooth Swelling and Pain.



