by Bryan L. Boone, DVM, is a general equine practitioner and an associate
with the Hagyard-Davidson-McGee veterinary firm near Lexington, Ky. A 1989
graduate of Oklahoma State University, Boone does much of the dental
work for the practice.
"We started breaking our yearlings and our veterinarian says some of them
need their wolf teeth taken out. What are wolf teeth, and why don't all
the horses have them? Also, why do they have to come out now rather than
earlier or later?
The majority of yearlings that are being broken will have wolf teeth, probably
about 75-80%. Wolf teeth are the first upper pre-molars, and they are
vestigial, which means they are not as fully formed as the other pre-molars
and don't really have a function in the horse today like they probably did
thousands of years ago.
They are located at the back of the interdental space-the space between
the incisors and the molars. Usually they are located just in front of the
upper (maxillary) second pre-molar, which is the first tooth that actually
looks like a molar. I've never seen a wolf tooth on the lower jaw (mandible),
but there are reports in the literature of them being there.
The bottom arcade is where the bit lies in most performance horses, but
in racehorses the bit tends to be up in that interdental space and hits those
wolf teeth in the upper arcade and can cause the horse problems.
Tradition has dictated that they are prophylactically taken out because
occasionally they cause problems with the bit, which fits in the interdental
space.
Trainers don't like horses to develop bad habits with their mouth, which
can happen if the horse is uncomfortable with the bit hitting a wolf tooth.
Trainers also don't want to stop on a young horse's training program to take
out a wolf tooth that is causing problems. Probably 99% of the people have
them taken out because they think at some point the wolf teeth will cause
problems. I'm not sure it's always justified, but as soon as you tell someone
they don't have to take the tooth out, it's going to be the one that will
cause a problem right before the horse is ready to make its first start.
So, wolf teeth are routinely taken out when yearlings are being broken
in the late fall or early in their two-year-old year. Usually they have erupted
or broken the surface of the gumline by then. Occasionally you have some that
haven't erupted, but you can feel where they are and usually see a reddened
area where they will erupt. You do this procedure when you are floating their
teeth and smoothing their pre-molars. In all, the process takes maybe 10-15
minutes per horse. Some can be hard to get out and be a more complicated
process, but usually it's not a long procedure.
In order to take them out you separate the periodontal membrane from the
small tooth. It's usually about a half-inch of tooth and three-quarters of an
inch of roots. The biggest tooth I've extracted was about three-quarters of
an inch long with roots an inch long. Even if they have not erupted, they need
to be taken out. They can still interfere with the bit.
Once you have the tooth loosened, you can lift it out by using the second
pre-molar as a fulcrum. There are some other instruments that go all the
way around the tooth and cut around it, but that's not the way I prefer to
do it.
I usually use sedation, but it's not necessary. It just seems to facilitate
the process and makes it easier on the horse, the handler, and the veterinarian.
Also, the palantine artery lies along the inside of the upper arcade. If it is
damaged it can bleed seriously, but it's not life-threatening. That's really
the major concern in extracting the wolf teeth.
Invariably, veterinarians and owners get busy and we don't get to the horses
that need to have this done before they start training.
The horses that have trouble with their mouth-the horses whose wolf teeth
really cause problems-are the ones that have wolf teeth that aren't right
against the second pre-molar. They are some distance away from that second
pre-molar. I guess because of the space the wolf teeth are not protected by
that second pre-molar. That lets the bit beat around on the wolf tooth and
causes periodontal disease, inflammation, and soreness around the tooth. Those
are the horses that the riders and trainers say need to be done right away
because their teeth are bothering them.
I've seen older riding horses, like Western pleasure horses, that are seven
or eight years old and have really big wolf teeth that don't cause any
problems. That's because they were positioned perfectly right up against
the second pre-molars.
I still feel I see more wolf teeth in colts than fillies, but just a little
bit more. That's not to confuse owners with canine teeth, which erupt when
the horse is four or five years old and are seldom seen in females. Canines
are also in the interdental space, but they are prominent, permanent types of
teeth. They are far more prevalent in males than females. They come in
equi-distant between the incisors and pre-molars. When you see canine teeth
in mares, they are usually on the bottom and are usually rudimentary."
Additional Thoughts:
The wolf teeth and canine teeth are often mistakenly thought to be the same.
The explanation of the difference in the article was very good. Colts and
fillies can have wolf teeth, but usually only the males will have the canine
teeth. There are 4 canines, two upper and two lower. It is not necessary
in most cases to remove the canines, although ocassionally they are rasped
down due to sharpness or excess length.
>>The bottom arcade is where the bit lies in most performance horses, but
in racehorses the bit tends to be up in that interdental space and hits
those
wolf teeth in the upper arcade and can cause the horse problems.
Tradition has dictated that they are prophylactically taken out because
occasionally they cause problems with the bit, which fits in the
interdental
space.<<
Except in harness horses wearing overcheck reins and racehorses that run
flat out, head extended, in full contact with the rider's hands, the bit
probably never touches the upper arcade of teeth. There are dentists that
put what is called a "bit seat" in the first premolars, but I personally
hope that my horse's bit is sitting quietly in his mouth and not jammed up
against the teeth! Most of the bit damage in riding horses tends to be to
the bars of the mouth (the space between the canines (if present) and the
first lower premolars), and to the tongue, lips and inside of the cheeks.
The inside of the cheeks are injured with jointed bits that can press the
skin down over the teeth. This pinching between the teeth and a metal bit
can be very painful to a horse. This last sentence, by the way, is my own
observation, and not something I've ever seen written in an article or book.
Wolf teeth, esp. the small, sharp, and often wobbly teeth just in front of
the large cheek teeth, can cut and cause pain with the bit pressing the
cheek skin into them. For that reason, I personally like to check for and
remove wolf teeth before a colt is bitted. I find when the colt is gelded
is a good time to check for and remove them--he's under anesthesia and they
are easy to remove then.
Wolf teeth that are NOT removed tend to be shed naturally when the horse is
2-1/2 to 4 years of age. That's the little ones, not those big, deep-rooted
wolf teeth.
>>I usually use sedation, but it's not necessary. It just seems to facilitate
the process and makes it easier on the horse, the handler, and the
veterinarian.<<
Well, shoot, man; I wouldn't want my dentist pulling a tooth (after first
prying up the gum with a sharp instrument--yow) without a nerve block or
anesthetic of some kind!
