If a tooth is visibly fractured, or if a large portion of the natural tooth is missing due to decay or an existing filling, it may be recommended to place a crown, or a porcelain cap, over the top of the tooth to protect it. While fillings are used to restore teeth with mild to moderate decay, they lack the strength to replace large portions or broken parts of teeth.
A common area for a tooth to sustain a fracture is on the backside of the lower second molars. The reason for this has to do with the forces this tooth sustains. The further back you go in the mouth, the more vertical pressure the teeth are exposed to. So your front teeth experience the least amount of force, and the furthest back second molar, the most. In particular, the backside of this tooth. Pair this pressure with the fact that there’s no tooth immediately behind the second molar to help distribute the heavy force, and this often results in fracture. These types of fractures, as well as extensive craze lines, or visible cracks extending across the surface of the tooth, are best protected with a crown
A tooth is prepared for a crown by reducing its dimensions so that the crown can be cemented on top of the tooth.
If the tooth does not already have a root canal, meaning its nerve has not yet been taken out, then there is a chance that the tooth will need a root canal in the future. Crown preparation (tooth reduction) is a necessary step to restore the damaged tooth, but it is also a traumatic insult to the tooth. The tooth was in an “unhealthy” state to begin with, having endured the trauma of a fracture or extensive decay. The cumulative effect of these multiple traumatic events in a tooth’s life can lead to eventual nerve damage. So if pain develops after the placement of a crown, then the tooth might also need a root canal.
After placing a crown on top of a cracked or fractured tooth, will my tooth completely heal?
Unlike a broken bone, the fracture in a cracked tooth will not heal. In spite of treatment, some cracks may continue to progress and separate, resulting in loss of the tooth. Placement of a crown on a cracked tooth provides maximum protection but does not guarantee success in all cases. The treatment you receive for your cracked tooth is important because it will reduce the likelihood that the crack will worsen.