What happens after a root canal?

If there is sufficient remaining tooth structure to restore (fix up) the tooth, root canal treatment may be the treatment of choice to avoid tooth removal and then replacement with a bridge or implant restoration.

It must be noted that often a crown (cap) is necessary to restore a root canal treated tooth in order to help avoid future fracture. If the tooth is not properly restored after root canal therapy, the root canal treatment may ultimately fail in addition to the tooth becoming non-restorable due to decay and/or fracture.

Therefore, root canal treatment may prevent tooth loss, but proper restoration of the tooth following treatment is absolutely necessary for success.
The best answer one can hope for is "nothing" -- nothing should happen. Assuming the root canal was successful (and most are), and a crown was put in place, your tooth should not bother you anymore, and in most cases, will remain trouble free for years (and even a lifetime). There will be some soreness after the procedure is done, but that's about it.

A root canal is a filling of the root of the tooth. After a root canal procedure, the top part of the tooth will need to be fixed and repaired. This is accomplished with either a filling or a crown. Your tooth will feel better, but it is normal for your tooth to be a little sore after a root canal. It may take several weeks for your tooth to heal.

After a root canal therapy (RCT) has been performed and the tooth is asymptomatic (does not hurt anymore) for best results the tooth should be protected by a crown. The reason is that once the nerve of the tooth has removed by RCT the blood supply to that tooth is also gone and over time it gets more prone to fracture. So by placing a crown over the tooth you are protecting it from the normal pressures of chewing that happens every day.

The tooth should be restored either by a filling or by a casting. If most of the tooth is remaining a filling can be used as the restoration. If not, a crown or a partial crown (on lay) should be completed to protect the tooth. Before the crown a buildup or post and core may be required.

Romesh Nalliah
Root Canal Treatment (RCT) has 2 important consequences that you should know. RCT is a procedure that removes all living tissues (blood vessels and nerve) from a tooth. It is necessary when decay has penetrated into the nerve tissues. 

Without a blood supply the tooth becomes brittle and more prone to fracture and this is the first important consequence you should understand. Usually, after RCT a tooth will need to be crowned. The crown helps to fortify the tooth and prevent fracture.

The second consequence of RCT is that the tooth will become darker. The crown also addresses this problem because it covers over the dark tooth and can be made to match the color of your other teeth. 
Nancy Jacobson
That really depends on 2 things. The first is the reason the tooth needed a root canal. The second is if the tooth is in the front (anterior) or in the back (posterior). Think of your tooth like a tree that has been hollowed out. It is more brittle and more prone to fracture because the system that kept it alive has been removed. If the tooth is a back tooth and needed a root canal because of a big cavity or a crack, it will need a build up or filling to seal off the roots, and then a crown to protect it from chewing forces.

If the tooth is a front tooth that was bumped or hit (trauma) but did not break or lose tooth structure it will not need a crown. If it is a front tooth that has lost most of the natural crown it will need a post inserted in the canal and then a build up and crown. The post is used in front teeth because the forces from chewing are mostly on the edge of the tooth. These forces can cause a brittle tooth to break at the gum line. 

Once Root Canal Treatment has been completed the tooth may be sore. Even though the nerves have been removed, this soreness is due to the fact that there is a cushion around the tooth that can get inflamed after Root Canal Treatment. Usually, this soreness will subside in less than two weeks. A tooth that has had RCT is more brittle then a tooth that has not been treated. This means that the tooth has a high risk of fracturing if it is used to chew. Thus, it is best to have a soft diet and eat on the opposite side until the tooth is restored. In order to be able to use the tooth in function it will be evaluated for restoration. This means that depending on the amount of tooth structure missing the tooth will need a procedure to replace the part of the tooth that is missing and then the tooth will need to be covered with a Crown. Once the tooth is restored, the tooth can be used to chew like your other teeth.        

A tooth that has had a root canal is more brittle than a "live" tooth. To protect the remaining tooth structure a crown should be placed.
After the root canal is completed, there may be lingering soreness for a few days. A follow-up visit to the dentist is in order so as to make sure that the infection has been cleared up; this may require another round of dental X-rays. You may also receive a prescription for antibiotics to ensure that the infection will not come back. Expect to go in for regular checkups every six months for continued, long-term monitoring.

Continue Learning about Root Canal Therapy

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.