Young horses often suffer more tooth problems than adults, especially during the transitional process when the temporary baby teeth are being replaced with permanent teeth.

It’s easy to see the horse’s incisors (front teeth) and witness their shedding and replacement with larger ones, but not so easy to examine the back teeth—and these are the ones that cause the most problems in the young adult horse. The temporary back teeth usually push up through the gums sometime during the foal’s first month of life. These baby teeth remain in place until they are pushed out by the permanent teeth. The 2- to 4-year-old horse is in the process of losing those baby teeth (often called caps), which are normally shed in sets of four. In textbook order, the first set of caps is shed when the horse is about 2 1/2 years old, the second set at 3 years old, and the final set of caps comes off at about 3 1/2 to 4 years of age.

Retained Caps

Not all young horses follow the textbook schedule, however, and the results can be painful. Unlike in humans, a horse’s baby teeth deteriorate as the new permanent teeth start to erupt, and the old ones become hollow—which is why they are called caps. But, sometimes these caps do not detach from the gums when the permanent teeth are pushing them out.

This condition is called a retained cap, and can cause inflammation of the gums, a painful mouth, and sometimes a sinus problem—if the retained cap is in the upper jaw. If the retained cap is not removed, it may cause the new tooth to grow in at an improper angle, or become impacted.

If a cap has to be removed, most veterinarians or equine dentists will remove the opposite one as well, so the mouth will match (top and bottom), to encourage proper eruption of the permanent teeth, and to avoid uneven wear.

Tooth Bumps

The mouth goes through many changes before the horse is five years old, and some of these changes can cause problems. Sometimes a young horse (especially between the age of 2 to 4) will develop bony protrusions on the lower jaw as the permanent cheek teeth come in. It’s not uncommon for the first and fourth molars to pinch the second and third molars as they emerge, temporarily inhibiting their upward growth—especially if the horse has a narrow lower jaw. This impaction creates the bony lumps on the bottom of the lower jaw.

Almost always the impacted teeth will gradually force their way up, and the problem generally corrects itself. The second grinding tooth usually comes in when the horse is three, and the third one emerges at age four. After they come into their proper places, the bone protrusions on the jaw smooth out and the lumps are usually gone by the time the horse is five or six years old (sometimes as late as 7). Occasionally the impaction won’t correct itself, however, and the obstructed teeth must be surgically removed. If a young horse has bony protrusions that rapidly become larger, or are quite tender when touched, a veterinarian should examine the jaw and mouth. Radiographs may be needed to see if the teeth should be taken out.

Wolf Teeth

Late yearlings, two-year-olds, and sometimes 3-year-olds, may occasionally have problems with wolf teeth, especially if the horse is being started in a bridle. Wolf teeth are technically called the first premolars, and are normally located in front of the upper second premolars and usually appear about 6 months of age. About 20 percent of horses (both male and female) have these residual teeth (not to be confused with canine teeth, which are in a different location, and which commonly occur in the male). Some horsemen routinely have wolf teeth extracted before the young horse goes into training. Most wolf teeth are easily located and extracted—a simple procedure that can be done by a veterinarian or an equine dentist. Normal wolf teeth can cause problems if a bit comes into contact with them; the bit may irritate, loosen, or even break this tooth. A wolf tooth may also lacerate the flesh of the cheek that is pulled back with the bit.

An unerupted wolf tooth can also cause trouble. It lies beneath the gum and cannot be seen, nor easily felt, but it can be irritated when the bit is pulled. The flesh covering the tooth can be bruised, and sometimes the action of a bit may eventually break the tooth even though it is still beneath the gum.

If a horse is suffering pain due to bit pressure on an unerupted wolf tooth, he may tuck his chin toward his chest to avoid contact between the bit and the wolf tooth, or he may carry his head to one side if he has only one wolf tooth. He may also carry his head abnormally high, mouth open, to try to avoid bit contact. If being trained for dressage, the horse may show violent resistance to a double bridle.

Any horse that has to carry a bit low in his mouth to prevent bit discomfort should be examined for unerupted wolf teeth. To check for these, put your index finger on the horse’s palate (roof the mouth), directly in front of the first upper grinding tooth, and move the finger back and forth on the gum to see if you feel a bump about the size of the end of your finger. Don’t press too hard or the horse may react in pain. If the horse has an unerupted wolf tooth, your veterinarian can extract it, making an incision through the gum.

Swollen Palate

Another situation that can create a sore mouth in the young horse is inflammation and swelling of the hard palate just behind the upper incisors. Called lampas, this condition can usually be detected when a youngster has trouble eating hard feeds such as grain or pellets, and goes off feed. The hard feed irritates and bruises the hard palate. Some horses experience swelling extending over the entire roof of the mouth. The solution for this problem is to feed soft feeds for a while until the mouth is not so sore.

Dental Check-ups

All too often a behavior problem or so-called training problem in a young horse is actually due to a sore mouth. A thorough examination by a veterinarian, with any necessary dental work being performed before the young horse goes into training, is often a good idea, improving the horse’s performance and avoiding any setbacks in training. Most veterinarians recommend that young horses’ mouths and teeth be examined twice a year from the age of two (starting even younger if a horse has any problems eating or chewing) until about age 5 or 6, or until all the permanent teeth have come in. An annual exam is then sufficient for most horses until they reach their teens.

Signs of Trouble

• Head tilting while eating or being ridden
• Taking a long time to eat
• Weight loss
• Long, unchewed particles of hay in his manure.
• bleeding from the mouth
• bad odor from the mouth or nostrils
• sensitivity to touch in the cheek area
• bolting grain
• spitting out unchewed wads of hay (quidding)
• changes in eating or drinking habits
• tilting the head back
• dribbling feed out the mouth while eating
• drooling or foaming (excessive salivation)
• irregular movement of the lower jaw
• bumps or enlargements on the jaw or sides of the face
• abnormal carriage of the tongue
• sharp points on the front of the first lower molars or the first upper molars.

—HST