Once upon a time, a badly decayed tooth was destined to be yanked. But the root canal allows dentists to save people from getting teeth extracted and keep as much of the healthy tooth as possible.

Here’s the essential information about root canals:

What is a root canal?

In a root canal, your dentist removes and cleans out badly decayed or infected portions of the tooth interior, including the nerve tissue or pulp, leaving behind the healthy portions of the tooth. The gaps are then filled in with a sealant.

To clean out the bad material, your dentist will numb the area, then drill a small hole into your tooth. Special files are worked into the hole to help scrub out the tooth’s root, and water is sprayed into the area to clean out the debris.

Your dentist may fill the hole with a temporary filling for a few days to allow any infection to heal before permanently sealing the tooth, or your dentist may fill the hole immediately.

What will this do to my tooth?

It will remove any decayed or damaged areas that could cause serious and even life-threatening infections. Because you’re removing nerve tissue, you may lose some sensitivity in that tooth — though the loss of the nerve tissue won’t make the tooth any less healthy.

Why would I need a root canal?

Root canals are used if there’s damage to the interior of the tooth — the nerve tissue or pulp — but there’s still enough healthy tooth remaining to allow the dentist to fill in and build a solid, healthy tooth.

Good dental hygiene and regular dental visits can help you limit the amount of damage and decay and may make this level of damage less likely.

Will it hurt?

Root canals have a bad rap, but this procedure is really painless — especially since the nerve tissues are often dead in the tooth that’s having the root canal. The area around that tooth may feel tender and sore after the anesthetic has worn off.

Will this tooth be healthy after it’s done?

In many cases, the root canal alone does the job removing the infected tissues and allowing the healthy parts of the tooth to survive. However, if the tooth is significantly damaged, you may need to have other work done to protect the tooth, including placing caps or crowns on the outside of the tooth.

Is there an alternative to a root canal?

The only other way to treat teeth that are badly decayed or damaged is to have them removed and replaced by false teeth.

Will I need to go see a specialist?

Root canals are a common dental procedure, which can be done by your regular dentist. You may also choose to visit an endodontist, who specializes in this kind of work, especially if your root canal may be challenging to complete. The endodontist will likely charge more for his services than a general dentist.