Hi...it is the third molar tooth or wisdom tooth which has less space to erupt.So in that area due to food accumulation and bacterial growth, it causes swelling and pain.Sometimes without medications it will subside.But without proper treatment it will recur again and again.The tooth has to be extracted if there is no chance of space for it to erupt.It will be identified through Xray/OPG examination.
Next Steps
Visit dentist immediately to avoid serious problems.
Health Tips
Add salt with luke warm water and gargle 4 to 5 times a day in the affected side to prevent further infection.
Advised to do regular dental check up and teeth cleaning every 6 months.