As with most things in dentistry, your wisdom teeth will be assessed clinically and radio graphically, meaning the dentist will look at them directly in your mouth and then study an X-ray. Both provide information and are used together to paint an accurate picture of the full situation.
They will want to see and check the following:
- Level of eruption. Whether the wisdom tooth is fully erupted, partially erupted (just poking its head through) or un-erupted.
- The angle. Is the wisdom tooth is visible and what angle it is at? Is there any chance it may come through fully and be useful? Is food getting packed next to it? Is the cheek or gum being traumatized?
- The position of the wisdom tooth- is it in line with the others or is it out to one side?
- Signs of infection. Is there any evidence of infection such as tenderness, swelling, redness, discharge of pus?
- Signs of decay. Are there any signs of decay in the wisdom tooth or the number seven tooth next door?
Are X-rays necessary?
- Opposing tooth. What about the opposing tooth- is it there? Has it been removed?
A good clear X-ray of the wisdom tooth or teeth is almost always required as part of the assessment. This is normally an OPG view
, though sometimes a Peri- Apical X-ray
will be used if you have a particular problem with one of your wisdom teeth.
There is much important information to note on the X-ray
, when assessing for extraction
When considering wisdom teeth extractions specifically, one of the most critical questions is how close the Inferior Dental (ID) nerve runs to the roots of your wisdom tooth. This only applies to the lower teeth.
Just because it looks close doesn’t actually mean it is; the OPG is a 2D picture of a 3D structure, so this must be appreciated.
Evidence that there is a close relationship is indicated by:
- A detour of the canal around the root
- A break in the thin white line of the canal (cortical bone surrounding the nerve)
- The nerve passing in-between the roots (rare but in these circumstances the risk of damage is very high).
In these circumstances, it can sometimes be advisable to get a 3D image in the form of a CAT scan to assess more precisely the route of the nerve and the potential risk of damage.
Because of the dose of radiation associated with this, it is reserved for those times where it will provide useful information about how best to approach the extraction procedure for your wisdom tooth
We discuss nerve damage and wisdom teeth
more in the risks and complications section.