Malocclusion in the chinchilla.

[Jade]

Malocclusion is unfortunately a very common disease and one many owners misunderstand. It is extremely painful for the chinchilla and close observation of your chinchillas can help to catch symptoms early.

There are several causes thought to be behind the disease. Among them are genetics, poor diet/nutrition, lack of calcium and vitamin C, injury, lack of items to chew on (toys, wood, etc.) for the front teeth, and lack of sufficient fiber (hay) to help keep the back teeth ground down. Because the disease can be genetically carried, it is recommended that no chinchilla with known malocclusion ever be bred.

Symptoms of malocclusion can include:

• Decreased food intake
• Eyes that look wet (often mistaken for an eye infection)
• Drool, creating a wet chin/chest area
• Weight loss
• Audible, frequent tooth grinding
• Pawing at the mouth, as if in pain

When the molar crowns overgrow, they can grow outward and/or curve inward. Upper molar crowns tend to curve outwards and the lower molars tend to grow inwards. Outward growth can cause tooth spurs, which will cut into and injure the cheek tissue, creating pain and likely infection. Inward growth can create sharp points that cut or even trap the tongue. Both of these make eating nearly impossible and terribly painful.

Not only can the teeth themselves overgrow, but the roots of the teeth as well. The roots can literally grow upwards into the eye sockets, or through the jaw bone. Often at this point, they can be felt along the lower jaw as bumps using your fingertips.

Malocclusion is usually a painful, often fatal condition. Early diagnosis can buy some time to trim the teeth themselves, but cannot correct root overgrowth. At the first sign of malocclusion, your chinchilla should be seen by an experienced exotic veterinarian. Unfortunately most cases are quite advanced by the time symptoms present themselves, making treatment often difficult.


Included below are some radiographs (x-rays) of a normal chinchilla and a severely maloccluded chinchilla. Normal radiographs are of my personal chinchilla (Praline) taken 3/5/04 and the maloccluded radiographs are used with permission, taken by the same veterinarian in February, 2004. Please note that the radiographs for Praline are a bit dark, but are clear enough to denote the differences.

Normal:


Maloccluded:


You can easily see the differences in this view. A normal chinchilla should have a nice straight alignment of the back teeth with little to no curving of the teeth or roots. The roots should be contained within the jaw bones, not protruding.

The maloccluded chinchilla has clearly visible overgrowth of both the molars themselves and the roots. The roots appear to be protruding into the eye sockets and out from the lower jaw. It also appears that the bottom incisor has been trimmed, probably due to overgrowth as well.





Normal:


Maloccluded:


In the normal view, you can see that the roots are nicely contained within the proper areas. In the maloccluded view, you can see the teeth growing outside of the jaw itself.




Normal:


Maloccluded:


In the normal view, you can clearly make out the eye sockets, a straight line between top and bottom back teeth, and no visible overgrowth of the roots.

In the maloccluded view, the eye sockets are nearly completely blocked from sight by overgrowth of the tooth roots, no line is visible to distinguish top jaw from bottom jaw, and the view of the jaw is barely visible due to root overgrowth.


As you can see, left untreated this condition can be very painful to the chinchilla and it will eventually starve to death. Sometimes the quality of life can be improved by trimming the teeth and giving pain medication, but not always. Once the roots overgrow to the degree pictured, a chinchilla is in constant pain and you, as a loving guardian, should consider the quality of the chinchilla's life and maybe discuss potential euthanasia with your veterinarian.




This article and its contents are protected by US Copyright laws. It may not be copied, reproduced, distributed, or otherwise re-written without express written consent of the author. Images not owned by the author are used with permission.

Links to the article are allowed. No permission is necessary to do so. Pictures are not to be used elsewhere, however I am happy to email the original, high resolution images of the normal chinchilla to a veterinarian for reference if needed. Contact info@chinnitude.com.

Here is a link to a fantastic chinchilla dental chart for your vet:
http://www.petsmile.org/vet/documents/chart-chin.pdf

[Chrisanne]

great info Jade!! Thanks for sharing. The xray pics really give a better idea than an explanation.

[Jade]

I thought they would be helpful too. I was nearly in tears when I saw this poor chinchilla's x-rays. I can't imagine how painful that must be.

[lipstickmafia]

ooh we just went over a whole bunch of information and pictures on Malocclusion in school.. that does look painful. we had a rabbit come in with such bad teeth that she couldn't eat at all.

[ckane]

I recently had to euthanize 2 related chins because of malocclusion. They both had molars growing into sinuses. It is truely heartbreaking to see a chins suffering from malocclusion.

[bossanovachin]

At what point would you euthanize, ckane? When it appeared to be bad by x-ray or were the animals already exhibiting the classic malocclusions signs? Do you supplement vitamin C? I'm asking because we have one gal with malocclusion but she's not exhibiting any signs yet and is full of spunk. She's three and we supplement vitamin C regularly, I think that's delaying the effects of her hereditary malocclusion. We had x-rays taken when we first got her from a pet store (she bit me on the nose so I just had to take her home and love her! LOL) and the malocclusion was clearly present then. She's due for x-rays again, but the yearly one so far have been unchanged- which I take to be a good thing in this situation.

[ckane]

The 2 chins I had to euthanize with malocclusion ( this was malocclusion of the upper molar roots growing into the sinuses ) showed no signs of malocclusion until they stopped eating and suffered from GI stasis (bloat) as a result of not eating. My vet who owns chins herself and had experienced the same problem, said there is no way to remedy this type of malocclusion, and GI stasis is very painful and difficult to treat. It was best to euthanize the chin to end it's suffering. The first chin was 6 months old and the second chin who exibited the very same symtoms less than one month later was her father. So this was definitely heriditary. I feed my chins a bit of calf manna and rose hypes for vitamin C. For a chin suffering from this type of malocclusion I would euthanize as soon as they show any symptoms because they are in a great deal of pain. If a chin in known to have this type of malocclusion before they stop eating the owner may wish to euthanize the chin so the chin does not have to suffer. Had I known these chins had the type of malocclusion that they had and the extent to which it had progressed, I would have euthanized. Please note that neither of these chins showed the classic symtom of malocclusion, drooling, both just stopped eating and got GI stasis as a result of not eating. Their eyes were a bit watery but that did not start until they stopped eating.

There are other types of malocclusion of the teeth. Sometimes the upper or lower teeth grow too long or are not in alignment. Sometimes this form of malocclusion is treatable with teeth trimming and the chins can lead a relatively good life.

For your friend who has a maloccluded chin, If the malocclusion is the upper molars growing into the sinuses the chin must be feeling pain if the xrays show it. I would euthanize the chin. This would be a difficult thing to do when the chin seems to be feeling fine, but chins hide illnesses. I would not want a chin to have to go through what my 2 did. It was very painful for them. I hope this helps.

[bossanovachin]

Thanks for the info! The malocclusion is in the molars and we keep her incisors clipped. Here's a pic of her on ChinCentral: http://www.chincentral.com/toothxrays.html

We've been keeping a close eye on her but she eats and doesn't appear to be in pain *at all* so we're reluctant to euthanize her yet. Would you say it's just best to wait until she stops eating or exhibits another sign of malocclusion then, so that we can be sure we're not just ending her life too soon? I know they can mask pain and that euthanasia is pretty much inevitable, but we don't want to put her down any sooner than absolutely necessary because we really love her- which is also the same reason we won't let her suffer and will euthanize if we think that's happening.

What's your opinion from looking at the x-ray? I'm not an expert on reading x-rays but our vet said it was progressive malocclusion that we need to keep an eye on but it's not critical yet. We haven't had to deal with this directly before, so I'm just interested in getting a feel for the situation from someone who has. That x-ray is her latest, it looks the same as the ones taken when we first got her. We think that the vitamin C may be delaying the problem, and over time her incisors haven't needed clipping as often as before.

Thanks, Cathy!

[Jade]

Yeouch. I just took a look at the x-rays and I'd say she's probably in pain. They hide it SO well. I know I would be if my roots were growing through my sinuses. I'd probably let her go if it were me, Sally.

[ckane]

The xray definitely shows upper molar malocclusion and it is pretty advanced. I'm not certain whether or not it has involved her sinuses yet, but it is awefully close if it hasn't already. Fortunately you know she has it and can monitor her very closely. When the sinuses become involved there is no doubt in my mind that the chin is in pain. Their breathing becomes involved. I did not have both my chins xrayed because it was pointless for the father of the first chin euthanized to be xrayed. He presented identically as his daughter. The xrays of the first chin showed heavy sinus involvement. I know you love your chin and a decision like this is very difficult. My best advice to you is follow your heart. You will know when it is time.

[bossanovachin]

Thanks so much for the input!! I think I'll schedule another x-ray in the next few weeks and see from there. It was so borderline with that last x-ray that it was hard to tell if the sinus cavity was really being affected or not, and it's true, they DO hide symptoms so well, don't they. Thanks again for the help and empathy, I'll update after the vet app't.

[bossanovachin]

Sorry to delay in posting the update, summer is pretty hectic here... Well, we had a miracle! I took our gal in for her dental x-rays and her teeth have actually IMPROVED! The previous x-ray was from two years ago, longer than I'd thought, but in those two years her teeth have done some major straightening and even receded FROM THE ROOT!! Yeah, they're not headed for the sinus/ ocular cavities anymore!! Is that crazy or what?

I had prayed for a miracle, and there you go! I mean, for teeth to recede at the ROOT, cripes, that's unreal! The vet even measured the difference on the x-rays herself. We got a couple molar spurs clipped, but besides that, she's not going to need to be euthanized! HURRAY! Here is the comparison/ contrast photo, from L to R is Before and (two years) After. We also supplement vitamin C and calcium (with phosphorous) to our chins, the vet believes that and a good diet with good hay really helped out:

[Chinchilla_Girl]

Wow! I'm no expert, but I did take a diagnostic imaging class in college and you can tell there is a difference! What do you use for vitamin C and calcium for your chins? I have one guy here that came from a petstore that I'm closely monitoring...I had him X-rayed when I first got him and he showed no signs even in X-ray of malocclusion but since he is from unknown background, I'm extra sensitive to him. He'll be due in a few months for another check up...all my other chins are from good breeders so I'm not too worried about them, but I do check teeth over weekly and feel along their jawlines for any signs of problems just to be on the safe side.

[lucy_minas]

my partners brother has some with malocclusion, they are fine, we snip their teeth low, so it doesnt rub into the skull or skin.
Its really common.

[Jade]

Quote: Originally Posted by lucy_minas my partners brother has some with malocclusion, they are fine, we snip their teeth low, so it doesnt rub into the skull or skin. Its really common.

I'm assuming you mean the front teeth? How do you snip them?