Why you should get your wisdom teeth x-rayed part 1

In general practice the dentist will normally examine you radiographically with 2 bitewing radiographs. These images will show most of the posterior teeth crowns and the bone levels. These images are great for detecting caries and or bone levels.

Some dentists will routinely carry out panorama radiography called panorals, that shows both upper and lower jaws, including the wisdom teeth; but the detail is not good enough to detect caries.

Because of the extra radiation most dentists do not take panoral radiographs as a screening tool.

If one needs more detail about a specific area or 1-3 teeth then a deeper peri-apical radiograph is taken.

All radiographs must be justified to provide a benefit to the patient. The radiograph must serve a useful purpose in aiding diagnosis.

All radiographs by law must be recorded in the notes as justified, graded for quality and also reported on.

It would make no sense for a dentist to take a radiograph and then not look at it. Sadly this happens a few times in general practice.

The dentist may have asked for radiographs to be taken but then forgets to look at them.

In this interesting case a patient attended in pain with the LR6 molar. He had pain under the tooth for a week.

We did a careful examination of the face, neck, soft tissues and the teeth on the left side.

We noted that the LL6 was slightly raised, mobile and tender to the touch.

A per-apical radiograph was requested of the LR6 LR7 region.

The radiograph would be graded 2 in quality because we do not have the whole crowns in view. It may just be that the teeth are very big in any case.

It was noted that the LR6 was heavily filled with a deep filling that may have encroached onto the nerve. At the apex there is some bone loss. This would indicate a non-vital tooth.

The LR7 however seems to have a dark area associated behind it. Now many dentists would not have seen the area, as they are so busy concentrating on the LR6.

So we took another peri-apical further behind to see what that radiolucency was.

The scene becomes much clearer now as we can see an unerupted LR8 or wisdom tooth, lying on its side. There is a large dark coloured radiolucency that surrounds the crown of the LR8. The area also extend to the LR7 and there is some tipping of the LR7.

The most likely diagnosis is of a dentigerous cyst. These are fluid filled sacs that originate from the cell lining over an unerupted tooth. This cell lining usually breaks down when the tooth erupts, but in unerupted teeth the lining may continue to proliferate and then the centre breaks down into a licid sac.

This is an example of a very large unilocular dentigerous cyst associated with an unerupted LR7 or LR8.

Dentigerous cysts are slow growing and usually painless unless another tooth becomes involved.

There can be a lot of bone loss or jaw deformity that can render the bone liable to fracture.

We informed the patient and sent him to the hospital for an emergency second opinion.

Normally a cone beam CT scan is taken to ascertain the extent of the cyst and if it has involved the dental nerve underneath.

The patient underwent a surgical removal of the LR8, LR6 and the cyst. The large hole left was filled with a bone graft.

Had we not had spotted the lesion the patient could have lost more teeth or even broken his jaw.

In conclusion always ensure the dentist lets you know what he or she found on the radiographs. That way you know they have checked.