Dogs are quite stoic beings and they may develop a tooth abscess of their carnassial tooth without giving out any outward signs. Carnassial teeth are commonly found in meat-eating animals. As the name implies, it derives from the French word "carnassier" which stands for carnivorous. An abscess of a dog's carnassial tooth is not uncommon as these teeth are often used to chew aggressively and on top of that, since they are located way in the back, dog owners often fail to notice signs of trouble.
A Lesson in Anatomy
You might not be much acquainted with your dog's carnassial teeth, but you have likely seen your dog put them to good use when he's gnawing on a bone or a chew toy and he's keeping his tilted sideways so to chew it with his back teeth.
Consider that dogs have 42 teeth comprising 6 incisors, 2 canines, 8 pre-molars and 4 molars in the top jaw, and 6 incisors, 2 canines, 8 pre-molars and 6 molars in the bottom one.
A dog's carnassial teeth consist of the dog's fourth upper molar (also known as tooth number 108) and the first lower molar. These two teeth meet together with their sharp edges just like shearing blades so to provide that strong shearing action carnivorous animals are known for.
The Onset of Problems
When all goes well, a dog's carnassial teeth work together to provide strong shearing action, but at times things can go awry.
As dogs get older, their carnassial teeth may weaken after providing years and years of action. A time may come when these teeth may fracture.
A fractured carnassial tooth may be caused by chewing hard items such as bones cow hooves, nylon toys, rocks and the bars of cages, explains Daniel T. Carmichael, a veterinarian specializing in veterinary dentistry.
If one looks at the carnassial tooth, one may see signs of a fracture. There may be a missing chunk from the side (slab fracture) or from the pointy part of the tooth, or the tooth may be heavily covered with tartar, which may be a further indicator of a fracture, since fractures may cause the tooth surface to roughen making tartar more likely to stick to it, explains veterinarian Dr. Scarlett.
Signs of Trouble
When the dog's upper fourth premolar gets fractured, bacteria are able to infiltrate within the gap and move towards the carnassial tooth's long roots creating a pocket of infection right under the dog's eye.
The swelling may appear anytime one of the this tooths' three roots gets infected.
After some time, the abscess may try to break out through a path of least resistance causing a pus-like discharge to seep through the skin or sometimes from the eye. Carnassial tooth abscesses are often seen in older dogs, generally over the age of seven.
Tooth Abscess Treatment
If my dog has a tooth root abscess of his carnassial tooth, what is the treatment? Can't antibiotics take care of it? If the dog takes antibiotics, the facial swelling may eventually go down or burst, but of the tooth remains there, the infection will eventually return as the problem tooth is still there, explains veterinarian Dr. Rebecca.
An extraction of the tooth would therefore be the ultimate solution, but those folks who have the fortune to have a veterinary dentist practicing nearby and can afford it, a root canal may be an alternative treatment.
Other Possible Causes
While a swelling under the dog's eye is most commonly due to a carnassial tooth abscess, there are also other possible causes for a swelling under the eye. A bug bite, an allergic reaction or even a cancer can be other culprits that the vet may want to rule out.
Generally, if the swelling presents right above the carnassial tooth, it's most likely a tooth root abscess though. "I see far more infections with that tooth than I do cancer in that area. A lot more" explains veterinarian Dr. Andy .
The only way to determine whether there is bone cancer, is by taking a biopsy from the problem area and having a pathologist evaluate it.
Disclaimer: this article is not intended to be used as a substitute for professional veterinary advice. If your dog has signs of a tooth abscess, please see your vet for proper diagnosis and treatment.