Identifying a symptomatic cracked tooth can be challenging.
There are a few methods that can help:
1) Waiting
Time will make the offending tooth known. This is usually because the symptoms (tenderness on chewing or thermal sensitivity) will tend to get worse if there is a truly cracked tooth. Radiographic (xray) changes related to a crack will also become more obvious.
Waiting also helps to eliminate other diagnoses, such as tooth tenderness from bruxism (grinding of teeth) or referred pain from sinusitis.
2) Removing all existing filling materials from the tooth
This allows direct visualization of the crack.
3) Opening up the gum
This allows vertical root fractures to be visualized. These tend to begin at the root tip inside the bone and travel vertically up towards the gum line.
4) Transillumination
A strong light beam is shone on to the tooth. A cracked tooth may only partially light up. This is not suitable if there are fillings or crowns on the tooth, and these should be removed before performing the test.
5) Dyes
Dyes can be used to trace hairline cracks. This is usually done after all fillings or crowns have been removed.
6) 3D xrays
A cracked tooth may look normal on a regular 2D dental xray where dense bone or other structures may obscure bone loss related to a crack.
