I have to admit when I first read about this, I was as surprised as you most likely will be.
Could teeth chattering signal a medical problem?
Believe it or not, it can. This comes to show the importance of assessing things in context. The context and circumstance make the difference most of the time.
I had only seen a dog chatter their teeth when we took Jasmine to pick up her new housemate. JD’s father was quite smitten by Jasmine, and his teeth were chattering up the storm. It would seem that he liked her a bit.
Are you cold or just happy to see me?
Emotional arousal can be a perfectly benign reason behind teeth chattering. It doesn’t need such a major reason, such as meeting the queen bitch of the universe, Jasmine. A dog can get this excited over a frisbee or a favorite meal as well. Both positive and negative excitement/stress can cause teeth-chattering.
Like humans, dogs can chatter their teeth when they’re cold or have a fever.
But there is one reason you’d likely not think of in a million years.
Oral pain
The most common cause of teeth chattering in dogs is oral pain.
“Teeth chattering is such a common symptom of oral pain, Fink says, that some dogs will chatter their teeth even when they’re under anesthesia.” ~Dr. Fink, Cornell University
How about that? There is not one specific oral problem that would have this as a hallmark symptom. The pain can be from a tooth fracture, tooth resorption, or enamel loss …
Neurological issues
Not as unexpectedly, teeth chattering can be a neurological problem.
Tremors or focal seizures can result in teeth chattering. A slower motion, which looks like your dog is chewing gum, can arise in the late stages of distemper infection.
Do you see now how important context is?
Related articles:
Symptoms To Watch For In Your Dog: Bad Breath (Halitosis)
Further reading:
Dogs and Teeth Chattering: What You Need to Know