If you have a tooth that is causing you a lot of problems with heat and cold, hurts all the time, and is causing your face to swell up, then you may be a good candidate for a root canal. You will need to talk to your dentist to see if it is an option and what they think the best thing to do for that particular tooth is. They will have to do x-rays and a full exam before making the final determination as to what your treatment will be. If you and your dentist decide that a root canal is the right treatment, you may want to know what the process is going to be.
Part of the root canal process is to get rid of all the pulp in the center of your tooth. It's that pulp where the root lives, which is what is causing you to have so much pain. It's also the part that is getting infected and where the bacteria thrive. To do that, the dentist has to get at the pulp, so they will drill an access hole. It's usually at the top of your tooth, but your dentist may move where they put the access hole depending on what tooth it is. They may also need to use files around the hole to get to all the pulp. If you tend to stress out about dentist appointments, you might want to talk to your dentist about being sedated for your treatment.
Once the dentist can get into the inside of your tooth, it's time for them to clean out the pulp of your tooth. There are several tools that the dentist may use to do this because it's important to make sure that they get everything. After everything gets cleared out, the dentist will probably put some medicine down into the tooth to get directly into any infection, and then they will put a temporary filling on the tooth.
Usually, dentists tend to wait about a week before they permanently seal the tooth. That way, if there is still any infection, they will be able to access it. When you see your dentist again, they will put a sealant in the tooth and either put in a permanent filling or install a crown to protect your tooth, depending on what you two decided.
If you are having a problem with a painful tooth, then you need to see your dentist. You may need to have a root canal.