Discoloured canine: endodontic treatment?

RE: Discoloured canine: endodontic treatment?

Lucy Fleming — Sun, 04 Jul 2021 11:10:14 GMT

Thank you - the dog is booked in with our nearest dentist for assessment and a probable root canal, I am happy to share the case outcome if anyone would like.

RE: Discoloured canine: endodontic treatment?

Jose C. Almansa Ruiz — Fri, 02 Jul 2021 04:44:31 GMT

Furthermore to what my colleagues have mentioned before, I would like to add that 1)teeth with the whole crown discoloured are in more than 90% of cases non vital as reported below, and 2), intraoral radiographs are not very sensitive to identify a perispical radioluceny associated to endodontic disease, its negative predictive value is 0.25, which means that for every 100 you think there are no signs of periapical changes 75 of them will have indeed some

RE: Discoloured canine: endodontic treatment?

Lucy Fleming — Fri, 18 Jun 2021 16:34:36 GMT

Thanks both. You're correct Evelyn, I shouldn't have described it as being the tip of the tooth that was discoloured - I meant more that the discolouration was more marked at the tip of the crown, and less so closer to the root, but yes most of the tooth is involved.

I will pass your advice on to his owner.

RE: Discoloured canine: endodontic treatment?

Evelyn Barbour-Hill — Thu, 17 Jun 2021 15:19:15 GMT

Good analysis by Rob.

I would add;

Personally from this picture I wouldn't call this "tip only", I'd call it nearly half the crown length.

As the dog is already 6 years old it's going to be a very long time – if ever – before you can be sure that the radiographic root canal is wider, or not, than the contralateral. So I don't think waiting and seeing is a good approach.

A radiograph now will tell you nothing about the pulp, but root fractures or any weirdnesses do need to be looked for. If there were, for instance, a root fracture, the extraction would be the only option. If you feel confident about doing an extraction, therefore, by all means do your own radiography first. (I put it this way because many GPs can indeed do the extraction even in this challenging situation, but many can not or would rather not. The big mistake is over-confidently embarking on an extraction and finding it turns into the wish-I'd-never-started nightmare)

If there are no complications of that nature, then extraction is a horrible very very very last resort. I would not mention it as an option, unless the client asks.

If the tooth continues to be painful then obviously treatment is required. Why delay?

If it ceases to be painful, either the pulp has recovered or it has died. I'm afraid that as the years have passed I've become ever more pessimistic about the likelihood of the pulp recovering. And if it's died, the sooner this column of necrotic material leading deep into the mandibular bone is removed the better.

You can probably work out that I'm advising endodontic treatment sooner rather than later.

Of course I'd be doing my own radiography, as radiography throughout the procedure is essential. Good radiographs taken by the referring practice can be helpful for advance assessment (as I discussed above), but the client may with justification prefer to avoid the delay and extra GA session. It depends on circumstances; there's no definite rule.

The way I work – personal preference – is to receive the patient in the morning, consult, examine and get on with the GA and everything that's required. Unless there's some complication or difficulty (in endodontics, expect the unexpected!), it will all be done in one day. Then I'd like a check-up consultation in a week or two. Generally that's it. If the client lives nearby, I'll do some monitoring, but if they have a distance to travel I leave that to the referring practice.

RE: Discoloured canine: endodontic treatment?

Rob Davis — Thu, 17 Jun 2021 10:58:54 GMT

This discolouration is due to blood leaching into the dentine tubules secondary to blunt trauma. Sometimes, if only the tip is affected then the resulting pulpitis can be reversible, but when most or all of the tooth is discoloured the inflammation is almost invariably irreversible resulting in pulp necrosis. The problem is that there is no easy way of telling if the pulp is vital.

If there is currently some discomfort associated with this tooth that would suggest that the pulp is currently vital but inflamed. If this is a recently injury, then radiographs are unlikely to tell you anything about the prognosis for the pulp (unless there are any root fractures etc).

I would suggest that there are two ways this could be approached: 1) analgesia and monitoring. If the oral discomfort subsides then the tooth could be monitored radiographically. If pulp necrosis has occurred then with time the contralateral canine pulp will appear smaller as more dentine is laid down with age, but the affected tooth pulp will be frozen in time as the odontoblasts will be dead. In a 6 year old dog this may take a while to be visible, but ideally would be radiographing every 6-12 months. 2) Assume that the tooth is endodontically moribund and treat now. Treatment options are extraction or root canal treatment (obviously RCT is preferable as the tooth can then be preserved).

My preferred option would be 2) as the dog's discomfort would be resolved quickly and it looks as though a good proportion of the tooth is discoloured in your photograph suggesting that the pulp will probably not survive. Root canal treatment for this type of case would normally be completed in one visit. Following RCT the tooth should be radiographed after 6-12 months check for signs of treatment failure.

Either way I would be staring the dog on NSAIDs if not contraindicated unless you have already done so.