Students get a lesson in horse dentistry

Dixie Crowe

Veterinarian, Dr. Jim Latham, CSU alumni, shows students the abnormal wear pattern in Cotton’s mouth called a wave. This happens when one tooth, in this case an upper molar was longer than the tooth directly below it on the lower jaw. Since the teeth are continuously growing, with proper dental care over a period of months this horse will eventually have a flat surface on each tooth. However, the veterinarian cannot grind too much surface off the longer tooth or he’ll risk exposing the pulp chamber and killing the tooth. Photo by Dixie Crowe.
Veterinarian, Dr. Jim Latham, CSU alumni, shows students the abnormal wear pattern in Cotton’s mouth called a wave. This happens when one tooth, in this case an upper molar was longer than the tooth directly below it on the lower jaw. Since the teeth are continuously growing, with proper dental care over a period of months this horse will eventually have a flat surface on each tooth. However, the veterinarian cannot grind too much surface off the longer tooth or he’ll risk exposing the pulp chamber and killing the tooth. Photo by Dixie Crowe.

If you ever wore braces, you probably don’t have fond memories of visits to the orthodontist. Biting on the blue paper or on pieces of wax to check your bite alignment; the plaster molds in the trays that made you want to gag. Then there were the scoldings that you weren’t flossing enough. Well really, does anyone floss enough?

As bad as all that was, at least once the braces came off all that was left was brushing and flossing at home, plus a little dental maintenance every year to keep gum disease away. Not true for our equine friends. Horses’ teeth are constantly growing and erupting from the upper and lower jaw into the mouth at a rate of about 1/8 of an inch per year, up until age 20. They have baby teeth like we do that will fall out as the adult teeth come in, but they’re softer than the permanent teeth.

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Because of the way horses chew their food in a side-to-side motion they can create sharp points and wear their teeth unevenly. This wear can even lock their chewing surface up if it’s severe enough. You probably got the idea; horses need to see the dentist, too.

Four veterinarians showed our equine disease class the dental abnormalities they found in our school horses as we watched them prepare for the exam, sedate the horses, make the diagnosis and correct the problems. We also had a set of skulls to examine with one of the veterinarians to really see the challenges they can face when horses’ teeth have both natural and unnatural wear patterns. Have you ever accidentally bitten your cheek? Not only does it hurt, but if you’ve broken the skin it takes awhile to heal. But imagine if your teeth were sharp and constantly rubbing that cut. It would be hard for it to heal and you might not feel like eating. If that sharp point isn’t ground down by the dentist it can make the opposing tooth wear down in the opposite direction.

As part of her exam routine, Dr. Garrison demonstrates a facial palpation on Roy before she even opens his mouth to look inside. If she can feel sharp teeth through his cheek she knows he will need help. Horses are sedated before the exam begins and their mouths are kept open with an oral speculum. The head can be held up with a rope and pulley suspended from the bar above stall door or propped up from the floor using a stand. Photo by Dixie Crowe.
As part of her exam routine, Dr. Garrison demonstrates a facial palpation on Roy before she even opens his mouth to look inside. If she can feel sharp teeth through his cheek she knows he will need help. Horses are sedated before the exam begins and their mouths are kept open with an oral speculum. The head can be held up with a rope and pulley suspended from the bar above stall door or propped up from the floor using a stand. Photo by Dixie Crowe.
Dr. Garrison uses a horse-sized dental mirror to look for periodontal disease in Roy’s mouth. Food stuck between his teeth can irritate gum pockets causing the swelling of the gum tissue and that is an indicator of early periodontal disease. Photo by Dixie Crowe.
Dr. Garrison uses a horse-sized dental mirror to look for periodontal disease in Roy’s mouth. Food stuck between his teeth can irritate gum pockets causing the swelling of the gum tissue and that is an indicator of early periodontal disease. Photo by Dixie Crowe.

Of course, since it was a disease class, we looked at really bad cases of dental diseases in the horses during the lecture. Probably the strangest one with the fanciest name was equine odontoclastic tooth reabsorption and hypercementosis disease where the incisors are actually rotting inside. Surprisingly a horse can have all its incisors pulled and still be able to eat just fine. Some horses will require routine maintenance every six months grinding off sharp points. Other horses that have more complicated dental issues may need to be seen every three months for small corrections until the chewing surface of the molars are even in both the upper and lower jaws. Some important signs that indicate dental problems in horses that owners can spot include:

  • Excessive salivation
  • Open mouth chewing
  • Dropping feed
  • Head shaking or tossing
  • Behavior issues with bit use
  • Unilateral nasal discharge
  • Mouth odor
  • Facial or jaw swelling

A veterinarian with dental experience should check horses that start showing abnormal behavior. This must be done as a full dental exam with sedation and a mouth speculum because horses will not willingly show you all their teeth.

Also, I would like to thank all the veterinarians who came to teach us about equine dentistry. I just found out they all came as volunteers to give us this amazing undergraduate experience. Thank you Dr. Jim and Patty Latham, Dr. Garrison and Dr. Taylor.

Veterinarian Dr. Taylor elevates Cash’s head, widens the opening of the oral speculum and attaches a light to the metal mouthpiece. Each veterinarian adapts commercially available equipment to fit his or her preferences and provide a comfortable experience for the horse. Notice the plastic tubing under Cash’s lower jaw. Dr. Taylor said he opens the speculum just wide enough to begin work on the upper teeth to not fatigue or overstress the temporal mandibular joint at the back of the jaw.  Photo by Dixie Crowe.
Veterinarian Dr. Taylor elevates Cash’s head, widens the opening of the oral speculum and attaches a light to the metal mouthpiece. Each veterinarian adapts commercially available equipment to fit his or her preferences and provide a comfortable experience for the horse. Notice the plastic tubing under Cash’s lower jaw. Dr. Taylor said he opens the speculum just wide enough to begin work on the upper teeth to not fatigue or overstress the temporal mandibular joint at the back of the jaw. Photo by Dixie Crowe.
Dr. Taylor uses a mechanical float to grind off the sharp points on Cash’s upper molars. It is essentially a small grinding wheel that is powered by a household drill. He will lightly grind each tooth to remove the point and visually checks to make sure he is not removing too much material. Photo by Dixie Crowe.
Dr. Taylor uses a mechanical float to grind off the sharp points on Cash’s upper molars. It is essentially a small grinding wheel that is powered by a household drill. He will lightly grind each tooth to remove the point and visually checks to make sure he is not removing too much material. Photo by Dixie Crowe.
Veterinarian Dr. Patty Latham, CSU alumni, shows the students the wear patterns in the molars in a horse skull. Notice the sharp points on what would be the tongue side of the lower molars. Because of the side-to-side grinding motion horses make when chewing there are also sharp points on what would be the cheek side of the upper molars. These sharp points are removed during floating, the term for taking off the points with a grinding wheel. Photo by Dixie Crowe.
Veterinarian Dr. Patty Latham, CSU alumni, shows the students the wear patterns in the molars in a horse skull. Notice the sharp points on what would be the tongue side of the lower molars. Because of the side-to-side grinding motion horses make when chewing there are also sharp points on what would be the cheek side of the upper molars. These sharp points are removed during floating, the term for taking off the points with a grinding wheel. Photo by Dixie Crowe.
Canine teeth are usually only seen in male horses though a small percentage of females do have them. The wolf tooth in the upper jaw is considered a vestigial premolar and serves no purpose in the modern horse. Usually it is pulled before a young horse begins training with a bit in its mouth. The bit sits across the bars, which is on the gum line between the incisors and premolars on the lower jaw. Photo and labels by Dixie Crowe.
Canine teeth are usually only seen in male horses though a small percentage of females do have them. The wolf tooth in the upper jaw is considered a vestigial premolar and serves no purpose in the modern horse. Usually it is pulled before a young horse begins training with a bit in its mouth. The bit sits across the bars, which is on the gum line between the incisors and premolars on the lower jaw. Photo and labels by Dixie Crowe.