Horse Dentistry.
Your horse's teeth - Out of sight out of mind.
By Dr Jenni Ahmat (BSc BVMS)
IVAS Cert . Vet Acupuncture (USA)
AVCA Cert Vet Chiropractics (USA)
In the last 5 years or so, there has been an explosion of interest in
dentistry for animals, and consequently there has been considerable
improvement in knowledge in this field.
Equine dentistry has its origins in the history of the horse’s long
association with humans, but has also undergone dramatic advances
recently.
Teeth are the starting point for nutrition, and the horse is not better
than what it eats, since how well the teeth can chew directly influences
how well the digestive processes work. Since nutrition is the foundation
of all animal husbandry, it is not surprising that in this era of
striving for maximum efficiency from the given ration, dentistry for all
species of domestic animals has come under the spotlight.
However, in the horse, there is the added factor that should interest
every serious horse trainer/rider in that there is a crucial
relationship between teeth and performance. Not all behaviour problems
are psychological or due to bad training and riding. Many originate
from pain in the body, and there is no part of the horse’s body more
sensitive than its mouth.
Indeed, the mouth is truly the mighty horse’s “Archilles heel”, as
humans have discovered to their benefit. The placement of a bit that
rests on the bars of the mouth or exerts pressure on the structures of
the mouth, allows us to control an animal ten times more powerful with
just the pressure of our hands on the reins. This system has worked well
for the last four thousand years during which time horses lived a less
confined life with plenty of grazing. Unfortunately today, many horses
are stabled and fed a processed diet, and many horse people are not well
acquainted with the inside of the horse’s mouth, or how pain in the
mouth can affect the horse’s body and performance.
This article will expose just how important correct dentistry is for the
very survival of your horse, as well as its quality of life, and the
behaviours and body postures that indicate mouth discomfort. This
article will also dispel the myth that properly attending to the horse’s
mouth consists of no more than a quick rattle around with a couple of
tools for a few bucks!
Just as good correct shoeing should be carried out by a professional
farrier, so should equine dentistry be the job of a dedicated
professional dentist or veterinarian. Basic work may only require basic
tools, and be a fairly quick job, but the more specialized work that
some horses require not only needs special equipment, but often also
needs the horse to be sedated to allow the work to be completed. In
these cases a good dentist may need to take up to an hour to do a
thorough job, and horse-owners should not be concerned by this, as if
the horse is properly sedated and restrained it will be quite unharmed
by having its mouth open for this time. Frequently when there is pain in
the mouth, the horse resents the presence of the dentist’s tools (think
how we ourselves cringe at the thought of the dentist!) and unless the
animal is properly restrained, and preferably sedated, in some
situations it is absolutely impossible for the dentist to accomplish the
job. In many everyday scenarios when the unsedated horse is playing up,
the dentist does the best he/she can, but is forced to leave what cannot
be done, and this is often the most important areas of the cheek teeth
at the back of the mouth .
Hopefully, as the profession of equine dentistry flourishes, there will
be greater acceptance of the fact that correct dentistry is not always
cheap and quick.
TEETH AND THE LIFE OF THE HORSE
It could be said that teeth are one of the most integral parts of the
horse’s life – they are constantly changing and reflect the process of
ageing and life-span. They are also essential for the horse’s favourite
activity of eating.
All creatures enjoy eating and their jaws go through the motion of
thousands of chewing movements every day. Just imagine how life would be
if every mouthful of food chewed was painful, especially when we
appreciate that the mouth has more pain sensors than anywhere else in
the body. What happens in the mouth profoundly affects the
Temporo-mandibular joint (TMJ), which is the joint between the upper and
lower jawbones. This joint is intimately involved with movements of the
junction of the skull, neck and spine, through the joints of the upper
neck, and is one of the most important parts of the sensory body,
telling the brain where the body is in relation to space.. Understanding
this complex relationship reveals just how important the horse’s mouth
is to what it does with its whole body.
Despite modern domestication, the horse is still obedient to millions of
years of evolution, and although we have changed its shape, we can never
change the way the horse’s body works.. In the case of teeth and feet,
growth is continual throughout the horse’s life because nature designed
this as a way to counteract the natural wear and tear on feet and teeth
brought about by the wandering life of a plains grazing animal, whose
coarse grass diet required a lot of chewing.
Continual growth of the teeth during life allows the horse to maintain
adequate tooth length despite the massive amount of grinding wear
incurred by chewing the tough pasture grass, however, in the modern
situation where most horses are fed processed grasses and cereal grains,
the amount of natural wear is much less because these foods require much
less chewing action. Therefore, if this excess growth of the teeth is
not controlled by regular “trimming”, or floating, as a substitute for
natural wear, then the horse can soon be in a great deal of trouble
because the grinding surfaces of its teeth will not occlude (meet)
properly. Then the horse cannot chew its food sufficiently well. In this
situation, the horse has difficulty maintaining condition, and is also
at risk of colic.
In fact, research has been done that demonstrates the connection between
horses that die of twisted bowel colic and poorly maintained teeth with
malocclusion problems.
In addition, the relationship between teeth and behaviour has been long
understood, as many behaviours originate from pain in the body. Indeed,
mouth pain can mimic and cause back pain. The horse avoids its mouth
pain by raising the head, then causing the back to drop and tighten,
thus building up a cycle of tension and pain whenever the horse is
ridden or sometimes even when it just has a bit in its mouth.
SIGNS OF DENTAL PROBLEMS
Most horse owners are familiar with the concept that the teeth need
attending to if the horse drops food while chewing. The motion of
chewing is an elliptical movement, and when the cheek teeth at the back
do not mesh well, the jaw cannot complete its chewing cycle and actually
locks up, so the horse has to open its mouth (hence the food drops out)
to be able to continue chewing. Dropping food is a very obvious sign of
tooth discomfort, as is drooling and bad breath.
However, many horses with problem teeth do not display these signs, and
it is these apparently “normal” horses that should still be receiving
regular dental check-ups.
Horses that eat very slowly, or have large pieces of forage and
undigested grain in their manure, and horses that do not put on
condition well are all candidates for troublesome teeth. Many of the
problems with poor occlusion may take years to develop, and therefore it
is essential to keep this in mind with the ageing horse.
Problems with bitting that indicate dental abnormalities include head
tilts, head tossing and bucking. All of these behaviours usually have
owners calling for chiropractors and other physical therapists, but the
money would be better spent calling a professional dentist who is
prepared to use a full mouth speculum to open the mouth and thoroughly.
VISUALLY INSPECT ALL TEETH.
When the bit is putting pressure on the flesh of the mouth, the horse
may try to relieve this by excessively chewing the bit, trying to shift
it away with its tongue. When this is not successful, the horse
graduates to fighting the bit, tossing its head, and depending on the
temperament, may develop other more explosive behaviours. Other more
stoic horses may just try to avoid the pressure of the bit on the sore
part of their mouth by turning the head away, wringing their tail, or
travelling crookedly to accommodate their desire to avoid their mouth
pain at all costs. When the mouth has been sore for some time, this
soreness then transfers to the TMJ and to the neck and back.
Consequently, performance is compromised and the horse may diagnosed to
have a chronically sore back.
TEETHING PROBLEMS
The first four or five years of the horse’s life are particularly
critical because equine teeth undergo the greatest change during this
period. Nutrition and growth is also very important during this time,
yet this is when many horses are subjected to the most intense training
and performance pressure, making for a situation that is ripe for
problems.
The most reliable visual indicators of a horse’s age, besides a brand or
tattoo, is the teeth, but to describe this complicated body of knowledge
is outside the scope of this article. Suffice to say that from the
moment of birth, the horse’s teeth are undergoing constant change.
Over the course of its natural life the horse will develop two sets of
36 teeth., Sometimes, as well as the regular set, some horses may also
develop vestigial teeth – called wolf teeth and also a set of canines,
or tushes. The first set of regular teeth are the deciduous, or milk
teeth, which are replaced by the second set of permanent teeth which
will grow and change shape over a lifespan. Soon after the foal is born,
the first 16 teeth are silently erupting, and by the age of 6 months
this number has gone up to 24.
When the permanent teeth beneath the deciduous teeth begin to push
through, the baby teeth are pushed up and out on top of the permanent
one, and are called “caps”. Between the ages of two and five years, 24
cheek teeth will erupt with up to 16 teeth erupting simultaneously! As
all human mothers can relate the far- reaching effects of teething on
small children, we must have empathy for what the young horses are going
through too!
In fact, this tooth shedding process is very uncomfortable for the
horse, and fortunately, it usually happens silently and smoothly by
itself. Sometimes though, the deciduous tooth doesn’t come out by
itself, and this creates the first major problem that develops in the
horse’s mouth is that of retained caps. These then interfere with the
eruption of the adult teeth and are very very uncomfortable, and will
also lead to severe malocclusion problems with lifelong effects. Because
of this, it is very important that young horses receive excellent
regular dental care. Many problem mouths are created by neglecting
dental attention.
ATTENDING TO OTHER DENTAL PROBLEMS
Most people think that floating the cheek teeth to remove the sharp
edges (floating is a word taken from carpentry and masonry and means to
“make smooth”) is the entirety of horse dentistry. However, floating is
a fundamental aspect of maintenance dentistry but is not the whole
picture, anymore than brushing one’s teeth is the sum total of human
dentistry. One concept that holds true, however, for both horse and man,
is that preventative care and correcting minor problems before they
become major problems is much easier to deal with than large scale
correction.
As we have said, the young horse should receive regular attention during
the periods when the permanent cheek teeth are erupting and coming into
wear.
Wolf teeth are the tiny vestigial teeth that in some horses appear in
their first year just in front of the first cheek tooth on the upper,
and sometimes, lower jaw. Most dentists recommend the removal of these
teeth in the young horse to eliminate any possibility that they may
interfere with bitting.
A professional dentist will also know how to place a bit seat in the
first cheek teeth to ensure that all types of bits will be comfortable
in the horse’s mouth. Many trainers have remarked that after the bit
seat has been created in the horse, it feels like the horse has “power
steering”.
As the horse ages, constant maintenance of the grinding surface of the
teeth by removing sharp edges prevents the formation of hooks and ramps,
which can severely interfere with chewing and cause the horse a great
deal of pain in the area where the cheek straps of the bridle contact
the face.
In horses with parrot mouths, or overshot jaws, the professional dentist
will know how to perform bite realignments to accommodate the change
with age in the angles of the incisors, which in turn affect the angles
of the cheek teeth at the back of the mouth.
DENTAL MAINTENANCE PROGRAMMES
Every horse, even if just a backyard pet, or a show champion, deserves a
thorough yearly examination, because NO horse is immune to dental
problems. This is an animal welfare issue that should be heeded by all
horse owners who do not wish their animals to be silently experiencing
pain. Severe problems are usually seen in the older horses, but they all
begin as minor problems with molar or incisor occlusions. If the horse
is attended to at least once a year throughout its life, these problems
would be eliminated.
In two and three year old horses cutting teeth, six monthly examinations
are advisable. When it comes to dentistry, prevention is worth a pound
of cure.
In summary, it seems certain that the demand for high quality dental
services will continue to increase. There is an increasing demand for
middle aged and older schoolmasters to keep performing, and for young
horses to be used in sport, and most trainers want their horses to
perform at their best, which they cannot do with dental problems. In
addition, feed savings from good dental care are likely to become more
of an issue as human and horse populations increase globally.