I have a sweeling in a right cheek,its not much sweeling,but it's their i had my rct in teeth 4 months ago so i don't know what's a reason. may be it could be a pus. plus help me thankx?

See your dentist: Post operative consultations are generally free. It would be a good idea to see your dentist for a quick evaluation. Ibuprofen is beneficial for swelling and inflammation. You may have an infection so your dentist will most likely get you on antibiotics. X-rays are necessary to ensure you don't have multiple teeth involved. Best of luck!

Re-evaluation: Have the dentist who performed the root canal therapy re-evaluate the area. There may be a residual infection that needs additional treatment.

Failed root canal: Inflamed, swollen gums are the most prominent sign of a failed root canal, as they may mean that the bacteria is continuing to irritate the surrounding tissue. Don't put this off. See your dentist or an endodontist as soon as possible for assessment and re-treatment.

See Specialist: See the root canal specialist - the Endodontist - for examination. The root canal treatment may not have been complete -- sometimes there are very small canals which get overlooked. Find an Endodontist that uses the microscope and possibly has a CBCT machine to best evaluate this. Do not wait. Good Luck.

Swelling: Swelling may be related to a failing root canal treatment, or it may have a totally unrelated cause. To be diagnosed you will have to be examined. Return to the General Dentist or Endodontist (root canal specialist) who treated you 4 months ago for a reevaluation.