Teeth have nerves in them that are responsible for the sensations they feel including discomfort when they are irritated. There are many irritants that can create pain or discomfort within a tooth. Some of these are:
- Deep cavity
- Cracked tooth broken/tooth
- Bad bite/clenching grinding
- Loose tooth
- Recent filling
- Resorption of the root
- A tooth that is no longer alive or has become infected
Nerves can undergo a certain amount of irritation and recover (reversible). During this recovery process it is normal to feel mild to moderate temperature sensitivity for a short period of time (a few seconds). However, sometimes the nerves do not recover from the irritant, and as a result a toothache develops.
This toothache is different from a reversible toothache in that the pain can persist for minutes or hours. It can be brought on spontaneously (can wake someone during sleep) or with irritation. Once a tooth has progressed to this stage a root canal treatment is necessary; otherwise, the only other option is to extract the tooth.
Following a root canal procedure it is not abnormal to feel discomfort to chewing or pressure on the tooth in question. This can last from a few days to a few weeks. Your dentist will give you a pain medication regimen to follow to minimize/prevent post-operative sensitivity. Typically, an anti-inflammatory such as ibuprofen or aspirin is an excellent choice as long as your medical doctor approves its use for you.
Back teeth (premolars/molars) are much more prone to fracture after root canal treatment. Research clearly shows placing crowns on root canaled back teeth drastically improves the long-term prognosis of those teeth. After these teeth are crowned, you can rest assured knowing that root canal treatments have a greater than 90% success rate at 10 years following treatment.