Teeth are like icebergs – most of the structure lies hidden away.
With the roots deep set into bone and covered by gum and other tissues - it is often only through the use of radiography and x-rays that we can properly assess dental health.
Dental X-Ray units are becoming much more common in veterinary practice. Indeed Pet Smile Month will be giving the one pictured above away to one lucky practice this year. It is important to have one that is highly manoeuvrable and where the head can be positioned to allow proper visualisation of the teeth.
Even though the dental x-ray units are relatively low output (especially when used for digital radiography) all of the dental staff team leave the room or are protected behind lead shields when the radiograph is being exposed.
Studies have shown that without dental x-rays a large amount of dental disease in cats and dogs can go undiagnosed. Intraoral radiographs revealed clinically important pathology in nearly 28% of dogs and over 40% of cats when no abnormal findings were noted on the initial examination. This explains why more and more vets are investing in dental x-rays and being trained in there use.
Adding radiographs onto a dental procedure will add costs. But the benefits for the patients are easy to see.
Here are some example radiographs:-
This tooth is severely by periodontal disease, so much so that the bone protecting the blood vessels along the jaw has been eaten away. Without a radiograph it would have been very easy to cause major haemorrhage and even jaw fracture.
Compare the tooth with the relatively healthy one on the opposite jaw.
A tooth root abscess is arrowed in this picture.
Can you see the abscesses in the picture below?
This cat had a chronic discharge from one nostril. Can you see which side and why on the radiograph of the cat's nose above?
The reason was a tooth root abscess stemming from a fractured tip of the upper canine (or fang). The tooth had been broken off and the gum had healed over - however the infected root tip continued to cause problems until it was removed.
Because the root tip was necrotic - x-rays were essential to make sure we had removed all of the material (as you can see above) - otherwise the problems would have continued.
Feline Odontoclastic Resorptive Lesions (or FORL), "neck lesions" as they used to be called can be difficult to diagnose without radiographs.
We also use x-rays a lot to confirm that we have fully extracted any roots - otherwise we can get the same sort of problems as the earlier case.
This immature canine tooth is fractured - but the picture below shows how badly the root is involved
This x-ray shows how sometimes the tooth roots can be very bent – without an x-ray vets could spend a long time trying to extract these teeth - or even worse may end up fracturing the root and leaving a root tip in place
Can you see where the decaying or caries hole is in this tooth?
The red arrow shows a retained "temporary", "milk" or deciduous tooth. The yellow arrow shows how wide the pulp chamber of an immature adult tooth is – indeed this tooth has not even properly formed its root yet.
However 4 months later you can see that the tooth is maturing well with the pulp chamber getting narrower and the dentine walls of the tooth getting thicker (the temporary tooth was extracted).
Now that you are getting good at reading these x-rays - can you see the root tip that has been left in place on this cat's upper jaw?
This was being operated upon for Feline Stomatitis Gingivitis complex. It is essential that all of the back tooth roots are removed. Without an x-ray the retained root would have possibly caused a continuation of the symptoms and pain.
The little root tip (circled in the radiograph below) was covered over by gum - without an x-ray it's presence would have gone unnoticed and treatment would not have succeeded. This is why dental radiography is such an important part of our armoury.
It is also important not to forget rabbits. Radiography is a vital part of the diagnosis of many dental problems. Dental disease in rabbits can present in many different ways – discharges from the eyes or wet chins, maybe increased soiling around their rear ends.
Radiographs can help immensely
The rabbit has an ET tube in the throat. If you look carefully at the lower jaw you can see that the first tooth is very bent and the root is overgrowing back into the jaw.
Here is a radiograph taken (with difficulty) inside the mouth. Rabbit dental disease is a whole subject in itself and we cover it elsewhere.
Finally - just to remind us that sometimes the unexpected turns up. We took a routine x-ray of a developing tooth (it had been subjected to trauma - not fractured - just bashed) and we wanted to monitor it to make sure that it would continue to develop OK.
Quite unexpectedly we found an extra root in the middle of the tooth. By recording this in the notes - should we ever need to extract this tooth - then we will know that it is not going to be straightforward right from the outset.
Increasing numbers of vets are using radiography as part of their dental health care programmes. Ask your vet about the benefits for your pet of having a radiograph at the time of a dental procedure.
Did You Know?
This illustrates how lesions can be hidden - this tooth looked normal when simply looking in the mouth.