Looking a Good Horse in the Mouth
Janice Eberhardt
The red orange sun casts warm dusty shadows over the splintery wood bleachers facing the small rodeo
arena in Vernal , Utah. Inside, the bay gelding Skyrocket Bar loops a tight right turn around the first
barrel in the cloverleaf pattern. He shoots to the next barrel for the left turn but, as usual, swings a wide
arc around it before rejoining the pattern, nailing the final right turn then speeding home.
Skyrocket is an athletic Quarter Horse from a good line of quick-footed stock horses. Barrel racing
should have been a snap for him, except for one problem: he couldn’t turn left. Despite practice and
determination, his left turns were as “stiff as two by fours,” his owner said. Consequently, he always
finished dead last.
The problem wasn’t his attitude. It was physiological, more precisely, dental. A diagonal slant across his
incisor teeth, from an untreated injury, made it impossible for the gelding to move his jaw enough to
crank his body around a left barrel turn.
Skyrocket is representative of about 75 percent of domestic horses that require some degree of dental
care in their lives. Today, an ever increasing number of horse owners are becoming educated about
dental care and seeking treatments for their mounts. In return, they see measurable improvements in
their horses’ performance.
Twice a year, Dr. Charmian Wright, a veterinarian specializing in equine dentistry, makes the rounds
from her base in Park City, Utah, to clinics organized by horse owners in outlying towns throughout
Utah, Colorado and Wyoming. It was a fortuitous day for Skyrocket when his owner brought him to one
of Wright’s clinics in Vernal for his first thorough dental check-up.
Once the gelding was standing comfortably restrained and sedated, his mouth propped open with a fullmouth speculum, Wright confirmed the problem that she suspected from watching the horse move and
listening to his owner describe his difficulty in turning. “The lower jaw has to move from side-to-side in
order for the horse to turn,” Wright says. The injury to Skyrocket’s front teeth created an imbalance
which allowed his jaw latitude to lead his body into right turns, but inhibited jaw movement for his left
turns.
“In human dentistry, we deal with decay,” she says. “ However, decay is not a common problem for
horses because their teeth grow continuously throughout their lives. With horses, we’re dealing with
abnormal growth and wear.”
After looking at and feeling each tooth and gap for abnormalities, Wright ground off the sharp points on
the gelding’s molars that were cutting into his cheeks and tongue. Then she extracted his two bottom
premolars, called wolf teeth. With this routine care accomplished, she then leveled Skyrocket’s incisors
using a Dremel powered cut-off wheel and grinder.
“The results showed literally overnight,” Wright says. Skyrocket’s left turns changed from board stiff to
rope-like flexibility around the barrels. Once free of his dental handicap, he concentrated his power into
setting a record time that still stands in Vernal.
“The majority of behavior problems are referable to pain,” Wright says. “Horses don’t intentionally
misbehave. They are such willing animals, we have to give them that credit.”
Wright says if a horse is comfortable, it is much more responsive to commands from its rider. One of her
other barrel-racing clients described the change in her horse. “The work has definitely improved our
time. She’s focusing on running instead of worrying about her mouth.”
Three quarters of the show and performance horses Wright examines are owned by women. “They
believe equine dentistry gives their horses the edge,” she says.
Shining Light into the Dark Cavern
“Horses’ mouths are very sensitive and private places,” Wright says. “It’s what they use to explore their
world, much the same way we use our hands to explore our world.” Yet until fairly recently, this central
sensor has largely been ignored by horse owners and veterinarians. And to a a great extent, the horse’s
mouth is still “out of sight, out of mind,” to many equestrians.
Traditional veterinary schools teach equine doctors how to “float” horses’ teeth, which involves shoving
a file into an unsedated horse’s mouth and grinding blindly on the back molars. This “abbreviated work”
is woefully inadequate, Wright says, because the whole mouth is not being addressed. “They miss the
back teeth, and the incisors are totally ignored,” she adds.
To perform comprehensive examinations, modern equine dentists have three advantages over their
predecessors: sedatives, the full-mouth speculum and power tools. Wright encounters very little
resistance from horse owners when she explains that the sedative/analgesic shot makes their horse’s
otherwise terrifying treatment (which many humans also dread) less traumatic and painful. The fullmouth speculum holds the patient’s mouth open and allows practitioners the opportunity to see and
feel each tooth, as well as providing the room need to work on the problems. Power instruments such as
floats, cutters and grinders make procedures faster and more effective than the hand-held float files
that are still widely used today.
When dong examinations on site, Wright uses her ingenuity to rig a rope halter suspension from
doorways, swing sets, trees, even a pickup truck’s roll bar, anything that will support the sedated horse’s
head while she examines its mouth with a bright flashlight and her fingers.
First, if the owner does not know, she determines the horse’s age from reading its incisors (which is a
whole story unto itself, she says). She looks for long unopposed molars, called hooks, then examines the
inside cheeks and tongue for scaring from sharp, uneven teeth. Most domestic horses and even wild
horses have sharp teeth, Wright says. She recently had a chance to study and compare the teeth of
euthanized wild horses from a herd captured east of Vernal that was afflicted with equine infectious
anemia (EIA) disease. She found, “They did have some sharp points, but not to the extent of domestic
horses.”
As Wright continues her examination, she looks for limitations in the range of vertical and horizontal jaw
movement that is essential for the horse to be able to extend and willingly flex its neck into collection
She also checks for occlusion, the percentage of space the molars grind food within. Eighty percent
efficiency is normal. A horse with malocclusions might have only 30 or 40 percent efficacy, leading to the
lift-threatening condition―starvation.
After seeing and feeling all 24 molars, then checking the interdental space (the gap where the bit rests)
for impacted teeth and addressing any problems with them, Wright then re-evaluates the 12 incisors to
make sure the mouth is properly aligned.
Wright stresses the importance of early dental treatment. Within a foal’s first three years, many changes
occur in its mouth. Emerging permanent teeth push out primary or deciduous teeth, and the new top
cheek teeth are often sharp. Because these changes are happening so quickly Wright recommends biannual check-ups for horses under five ears old (just like human children). If a foal has serious problems,
such a jaw malalignment, she can put corrective braces on it.
Young horses also have long-rooted canine teeth coming in―or at least they should. Mares often have
impacted canine teeth that make the bit particularly irritating for them. Male horses can have impacted
wolf teeth or residual canine teeth. In most cases, these problem teeth can be extracted from the
mouth while the horse stands sedated, she says.
At the age of five, when horses are typically ready for saddle training, Wright recommends having a “bit
seat” ground and smoothed on their canine teeth and first premolars to help the bit fit more
comfortably in their mouths.
The initial comprehensive exam typically takes one hour, Wright says. Annual follow-up exams in fourto five-year-old horses take less time, but are essential to keep their teeth even and mouths comfy.
As horses reach their senior years, beginning around 20 years old, they begin to lose their mature teeth.
This creates gaps in their dental platform for unopposed teeth to grow into. So regular dental
maintenance prevents problems such as Skyrocket’s jaw impairment. Older horses also require softer
and more moist feed, Wright says. There are several food products available for senior horses. “If you
maintain dental and nutritional balance, you can add five productive years to a horse’s life,” Wright
adds.
Breeding and Bits
Extensive cross-breeding of horses with different head sizes has resulted in horses with more extensive
dental problems than breed who have stayed within their size range, Wright says. “People aren’t
breeding horses for dental traits.” She refers to the wild Przewalski’s Horse who has a proportionally
bigger head than say, an Arabian-Saddlebred cross from two breed with drastically different head sizes.
“Bigger-headed horses don’t have as many occlusion problems,” she says.
Wright is also interested in studying the effect of the bit in horse’s mouths. “Bits are not as mild as we
think,” she suspects. She’s examined horses suffering from bit cuts on their tongues and lips and under
their chins. Though many equestrians think the snaffle is the mildest bit for horses, Wright says the
majority of the damage she’s seen is from snaffle bits. She theorizes that even when the horse’s mouth
has dental preparations to accommodate the bit, the snaffle presents only one pressure point to control
the horse. The curb bit, on the other hand, provides three points of control: the bit, the chin strap and
the headstall. More pressure locations can reinforce the rider’s commands to the horse, thus requiring
less rein tension and unnecessary discomfort.
Wright says she disagrees with the concept that curb bits are cruel, “One thing I have not seen is
damage from a high port on the roof of a horse’s mouth.
“We speculate on how bits work, but until we get the imagery to see how they really work, we still don’t
know. It’s a very complex interaction,” Wright says.
Spreading the News
In her fifth year of equine dentistry practice, Wright is doing her part in sharing her knowledge with vet
apprentices, practitioners and horse owners about the necessity of integrating annual dental check-ups
with horses’ routine care―along with de-worming, vaccinations and hoof maintenance.
Wright grins as she reflects on Skyrocket’s barrel-racing success. “I’ve worked on every type of
horse―from ranching to performance. Whether the horse costs $50 to $1 million, they all benefit from
regular dental maintenance.”