When Barry started showing signs of discomfort eating, his owners checked him over and noticed that he had a wobbly tooth and brought him along to see us at South Moor Vets. Between us we decided that he’d benefit from having a dental to look after his teeth, but unfortunately Barry was hiding a bit of a secret.

Barry’s mouth was sore, but it wasn’t just one tooth that was wobbly. When we checked him over, it became apparent that all his teeth were moving a bit. They were still well anchored in his jaws, but the jaws themselves had become soft and bendy! We’re lucky to have digital dental radiography in all our clinics - Dental xrays are a vital tool for assessing the dental health of our patients -and so we took some images of Barry’s jaws.

Have a look at the xray pictures here. The one at the top is a normal dog skull. The one at the bottom is Barry, and if you look carefully you can see that the teeth stand out really obviously. That’s because the jaw bones are far less white than they should be. A lot of the calcium has disappeared from the bones, and that tells us that Barry has a pretty rare condition called “fibrous osteodystrophy”, also known as “rubber jaw”.

“Rubber jaw” is not a disease itself, but rather a clinical sign of a larger problem—typically severe calcium deficiency due to a condition called secondary hyperparathyroidism. This occurs when a dog’s body is unable to properly regulate calcium and phosphorus levels, often due to chronic kidney disease or poor nutrition, particularly in young, growing dogs on an imbalanced diet.

The term “rubber jaw” refers to the softening of the jawbones, which can become so weakened they feel rubbery or pliable to the touch. This happens because the body starts breaking down bone tissue to maintain critical calcium levels in the blood. The jawbones, being relatively thin and less dense, are often among the first to show signs of demineralization.

Rubber Jaw can be cause by an imbalanced diet (Nutritional Secondary Hyperparathyroidism): This is usually seen in puppies fed diets that are too high in phosphorus and too low in calcium, especially home-cooked or raw diets that aren’t properly balanced. Rubber Jaw can also be cause by kidney disease (Renal Secondary Hyperparathyroidism): Seen more in adult or senior dogs, this occurs when damaged kidneys can no longer properly regulate phosphorus and calcium, leading to hormonal changes that result in bone loss. Other diseases can more rarely cause rubber jaw, such as tumours or other endocrine disorders.

Treatment focuses on addressing the underlying cause. For nutritional cases, such as Barry’s, immediate diet correction and calcium supplementation are required. Unfortunately, if the condition has progressed significantly, some of the bone loss may be irreversible, though early treatment can halt further damage.

Prevention is Key: Feeding your dog a complete and balanced diet—especially during growth stages—is critical. Avoid creating home-cooked or raw diets without veterinary guidance or the supervision of a pet nutritionist. Regular veterinary check-ups, especially for older dogs, can help detect early signs of kidney disease or other metabolic disorders.

Barry is now on a treatment for his Rubber Jaw and we all have our fingers crossed that he will make a full recovery.