Expert: Mark Bornfeld DDS - 9/18/2006

Question
What tests do endodontists do to determine the need for a root canal? Any special tests for cracks or fractures?

Answer
Dear Diane,

For the purposes of my answer, I will slightly rephrase your question to read "What tests do endodontists do to determine whether a tooth pulp is diseased". This is a bit of a technicality, but members of any dental specialty-- endodontists included-- are best suited to making treatment decisions within their own specialty ONLY. A tooth may indeed have an infected pulp, but the appropriate treatment may be extraction rather than root canal therapy if, for example, the tooth is too structurally weak to be reliably re-built. For this reason, it is always best for specialists to collaborate with the general dentist when formulating a plan of treatment.

A full exposition on endodontic diagnosis is beyond the scope of this forum. However, there are several diagnostic modalities used in determining the health of a dental pulp:

1. Patient's oral history of symptoms and previous treatment to tooth. For example, a patient may have developed sensitivity to cold stimuli that worsened over time, only to disappear and then notice the tooth was uncomfortable with application of biting pressure. An oral history can not only suggest pulpal injury, but can also imply the stage in pulpal degeneration.

2. The referring dentist's reported treatment history. This can provide objective data that can often clinch a diagnosis.

3. The radiographic picture. An x-ray may disclose deep decay, a deep filling, or directly reveal disease within the pulp itself or in the tissues adjacent to the root of the tooth. Equivocal recent x-rays can be compared to previous x-rays in a patient's record to assess any changes that may have occurred over time.

4. The visual appearance of the tooth and surrounding tissues. A tooth may have an obvious abscess, as evidenced by purulent exudate, a draining fistula in the adjacent gum tissue, or obvious exposure of the pulp of the tooth.

5. The response of the tooth to various stimuli. A stimulus can be applied sequentially to one tooth at a time- for example, heat, cold, electrical stimulus, or percussion. This not only can detect pulpal injury, but can also isolate the problem to one tooth if it is unclear just which tooth is responsible for symptoms or other diagnostic signs.


Testing for cracks is more potentially problematic, since the response to clinical tests is often unclear, and may suggest problems other than tooth fracture. Cracks can almost never be seen on x-ray. The most reliable method of detecting cracks is direct visualization under high magnification. This is becoming increasingly popular, as more endodontists are equipping themselves with high-magnification operating microscopes. However, it is sometimes difficult to distinguish a significant crack from the very common surface crack that has no clinical implication. Other ways to test for cracks involve percussing one part of the tooth at a time, or using a device such as a "Tooth Slooth" (see http://www.toothslooth.com/Product-ToothSlooth.html )

Hope this helps...

Mark Bornfeld DDS
www.dentaltwins.com
Brooklyn, NY