Mandibular brachygnathism in a kitten

Re: Mandibular brachygnathism in a kitten

Rob Davis — Fri, 30 Jan 2015 22:05:36 GMT

Touche!

Re: Mandibular brachygnathism in a kitten

Evelyn Barbour-Hill — Fri, 30 Jan 2015 21:32:14 GMT

[quote user="Rob Davis"]I have successfully resected one or two, but I had one severe one recently in which I did end up shortening the cusp of the upper carnassial (I'm surprised that Evelyn didn't correct your "molar" as this is the upper fourth premolar - clearly he's not in pedant mode ).[/quote]

I'd have mentioned it if it had been you posting, Mr. Davis!

Actually this division into molars and premolars is a comparatively recent thing – they used to be all known as molars, or indeed as grinders, in the nineteenth century – and in my opinion is an artificial and unnecessary division.

And one might mention further that all the teeth of the cat, distal to the canine teeth, are carnassial teeth (as are those of the dog, except for the maxillary 9s and 10s, the mandibular 10s and 11s and the distal portion of the mandibular 9).

So there.

Re: Mandibular brachygnathism in a kitten

Busybee — Fri, 30 Jan 2015 20:20:42 GMT

Got away with that one!

Will see how kitty goes for now - fingers crossed!

Re: Mandibular brachygnathism in a kitten

Rob Davis — Fri, 30 Jan 2015 19:34:38 GMT

I do see these from time to time. I have successfully resected one or two, but I had one severe one recently in which I did end up shortening the cusp of the upper carnassial (I'm surprised that Evelyn didn't correct your "molar" as this is the upper fourth premolar - clearly he's not in pedant mode ). If you are doing this you do need radiography to determine where the pulp is.

Re: Mandibular brachygnathism in a kitten

Evelyn Barbour-Hill — Thu, 29 Jan 2015 22:49:54 GMT

Most interesting.

Re: Mandibular brachygnathism in a kitten

Busybee — Thu, 29 Jan 2015 19:55:12 GMT

Ok, so my memory is really bad - it was the upper molars pinching on the lower gum, not the canines!

Saw the cat today. I have (tried) to attach a couple of photos. Unfortunately, I had resected the worst side before I remembered my camera so 2 of the photos are of the left, less severely affected side before resection (you can just about make out a crater shape where you could imagine the upper molar would make contact) and the third is the right side after resection. The right was similar but a much bigger 'crater' and inflamed tissue. There is no contact between the molars and gum now so hopefully it will not come to taking the healthy teeth out

Re: Mandibular brachygnathism in a kitten

Evelyn Barbour-Hill — Thu, 29 Jan 2015 01:51:54 GMT

[quote user="Busybee"]

I don't have a specific gingivioplasty burr but do have tapered diamond burrs for a high speed handpiece - would this be ok?

[/quote]

I don't know what type and grade you have. Not too coarse, and a bullet or "football" (American football!) or pear shape would be best. Idly browsing just now, I see somebody recommending a 12-fluted carbide bur, which is something I must try... I think I'd want to use a brand new one each time if I did.

Use a light touch.

Re: Mandibular brachygnathism in a kitten

Busybee — Wed, 28 Jan 2015 18:41:41 GMT

Many thanks all!

Rob - not quite, it's the upper canines impinging on the lower gum, creating a crater-like ulcer. Will try to get photos tomorrow.

I don't have a specific gingivioplasty burr but do have tapered diamond burrs for a high speed handpiece - would this be ok?

Re: Mandibular brachygnathism in a kitten

Tom Ward — Wed, 28 Jan 2015 18:26:10 GMT

The January edition of JFSM has a lengthy section on malocclusions in cats. Might be worth a look!

http://jfm.sagepub.com/content/17/1/5.abstract

Re: Mandibular brachygnathism in a kitten

Evelyn Barbour-Hill — Tue, 27 Jan 2015 23:17:18 GMT

[quote user="Busybee"] Can I simply excise the ulcerated area of gum until no more contact is being made (don't think it will require much tissue to be removed)[/quote]

As Rob suggests, well worth a try if you are handy at sculpting tissue.

You can get special diamond FG burs actually designed for gingivoplasty.

[quote user="Busybee"]would I be looking to shorten the upper canines (how? Never done this)[/quote]

Send the case to me?. Well, refer to somebody who specialises. It should not be expensive.

[quote user="Busybee"]or even remove them?[/quote]

Aaaaaarrrrrrgggghhh! Wash your mouth out with soap and water!

Re: Mandibular brachygnathism in a kitten

Evelyn Barbour-Hill — Tue, 27 Jan 2015 23:06:08 GMT

"Occasionally" is a suitably vague word.

I would dispute "always".

It's not too hard to determine whether the canine teeth are forming any sort of lock (not necessarily a dental interlock, it might be teeth "locking" into depressions into which they are occluding) that might restrict growth of the mandible.

You do offer free monthly check-ups to vaccinated puppies until they are over six months old, don't you? So of course you can keep an eye on the dentition.

It's also often easy with the eye of experience to make a pretty good wager as to whether the apparent jaw disparity is just temporary, due to different rates of growth, or a true brachygnathism.

I don't know of any meaningful studies. How could it be done? You would need a large number of puppies assessed as having jaw disparity and then extract teeth from only half of them. Ideally all of one breed too.

Re: Mandibular brachygnathism in a kitten

Rob Davis — Tue, 27 Jan 2015 18:31:26 GMT

[quote user="Evelyn Barbour-Hill"]Puppies quite often show disparity in length of maxilla and mandible during the period of rapid growth but end up with a normal or near-normal occlusion (and it is occasionally a good idea to extract canine teeth in such cases to prevent an abnormal occlusion locking the jaws together as it were). [/quote]

I am surprised that you consider it only "occasionally" a good idea to extract deciduous canines in puppies with mandibular brachygnathism. My understanding from other dental specialists is that these should pretty much always be extracted to avoid dental interlock preventing the mandible from reaching its genetic potential length. It is obviously impossible to know in individual cases whether or not early extraction has made a difference. Do you know of any studies looking at this?

Re: Mandibular brachygnathism in a kitten

Rob Davis — Tue, 27 Jan 2015 18:26:12 GMT

[quote user="Busybee"]Can I simply excise the ulcerated area of gum until no more contact is being made (don't think it will require much tissue to be removed)?[/quote]

Difficult to comment without pictures, but is it similar to this:

If so, I treated this by gingivoplasty using a diamond bur on a high speed handpiece to recontour the gingiva so that the lower canine was no longer touching it. It healed fine and has not looked back.

[quote user="Busybee"]O would I be looking to shorten the upper canines (how? Never done this) or even remove them?[/quote]

Shortening canines is not simple. It will almost certainly require some sort of endodontic treatment which requires a fair degree or learning, equipment and appropriate materials.

Re: Mandibular brachygnathism in a kitten

Busybee — Tue, 27 Jan 2015 18:05:08 GMT

Sorry to hijack the thread but I have a similar case I'm seeing again on Thursday.

18mo FN DSH who I saw for vaccination a few weeks ago. The owner reports she has 'always' had intermittent head shaking and shuddering/shaking jaw when she eats (hadn't been noted before in the notes). Aural exam was unexciting. Oral exam similar other than her upper canines both sides are making contact with the lower gum and causing ulcers.

My plan Thursday was to sedate her to fully examine her ears and mouth and look to take skull radiographs to examine the TMJs and the middle/inner ears. My main question is what to do about the teeth? Can I simply excise the ulcerated area of gum until no more contact is being made (don't think it will require much tissue to be removed)? O would I be looking to shorten the upper canines (how? Never done this) or even remove them?

No pictures I'm afraid but may try to get some Thursday.

Re: Mandibular brachygnathism in a kitten

Oli_J — Mon, 26 Jan 2015 06:33:26 GMT

Thanks for the advice! Good to know things can be left 'as is', I really wasn't looking forward to extracting the canines in this little guy.

Oli

Re: Mandibular brachygnathism in a kitten

Evelyn Barbour-Hill — Sat, 24 Jan 2015 23:11:32 GMT

I do not think that removing any canine teeth would help mandibular growth and development.

Puppies quite often show disparity in length of maxilla and mandible during the period of rapid growth but end up with a normal or near-normal occlusion (and it is occasionally a good idea to extract canine teeth in such cases to prevent an abnormal occlusion locking the jaws together as it were).

This does not seem to happen however in cats: in my experience if the cat is brachygnathic, it's brachygnathic.

It's a bit of a myth that lower canine teeth impinging on the palate will dig ever deeper holes. Yes, the pressure will cause a bit of a pit to form, but once the mouth has reached the limit of closure then the canines cannot put any further pressure on the site. So sometimes the matter needs something doing about it, but often it does not. Sometimes the lower canines are damaging the gingiva of the upper canines, and then some treatment would be advisable.

I wouldn't mess with these milk teeth unless they are doing observable damage. The permanent teeth once fully erupted you can assess, and my guess is I would be advising shortening by a little bit – probably only a couple of millimetres, maybe three. There would be absolutely no need for the drastic step of extracting them.

Re: Mandibular brachygnathism in a kitten

mariette asselbergs — Sat, 24 Jan 2015 21:48:58 GMT

I think I would wait and keep an eye on developments. My own EBT puppy had the same and over the first year her teeth and jaws developed in a very acceptable way, even though as a puppy it looked very worrying. It looked to me as if the under K9s would simply pierce through her upper gums, but after 8 or 9 months that did not happen. What I did do was play regularly with her with a kong ball. Can you think of something similar to do with this cat?

Mariette