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Dental check-up and
determining age
You can find more about horses here
Introduction
All horses have their teeth examined at least once a year by a veterinarian or well-trained equine dentist to see whether they have developed any sharp edges which might make chewing, or responing to the bit, painful. In the case of horses being asked to perform very precise work such as dressage, it may be necessary to check them more often than this because even the slightest discomfort may cost vital marks.
The problem is that the horse's molar, or cheek, teeth of the upper and lower jaws meet with an awkward grinding surface. It slopes upwards from the outside (or cheek surface) of the teeth up to the inside (or tongue surface) of the teeth. If the upper and lower jaw just opened and closed, this would not create any problems. As it is, however, the horse moves its jaws around from side to side in order to grind the food before swallowing it. This grinding action also grinds the teeth and can result in extremely sharp cusps or edges developing. These sharp edges develop on the outside edge of the upper molar teeth, and the inside edge of the lower molar teeth.
Clinical signs
Dental problems, from painful points to rotting teeth, may cause difficulty chewing or “quidding,” which occurs when food falls out of the mouth. Other signs of dental disease may include foul breath, undigested hay in the stools, or discomfort from the bit or noseband. Dental disease can lead to choke, colic, and weight loss.
Some horse owners think the teeth problems only arise in old horses. It is certainly tree that their effect is particularly marked in old horses. The combination of discomfort during chewing and reduced digestion of improperly chewed food can resullt in a thin old horse which will not eat at all. Nevertheless, even young horses have teeth and chew food with them, so even young horses can develop problems.
If an examination does reveal sharp tooth edges, your veterinary sugeon will rasp or file the teeth to get them smooth and even again. It is usually more effective to do this using a device called a gag to hold the horse's mouth open and so preventing it from holding the rasp firmly between its jaws. The gag also enables a proper examination of the mouth and teeth to be carried out.
Determining age (from Wikipedia)
Birth: only the two nippers or central incisors appear
One year old: all the incisors of the first or milk set of teeth are visible
Three years old: permanent nippers/incisors have come through
Four years old: permanent dividers next to the nippers have emerged
Five years old: the mouth is perfect, the second set of teeth having been completed, including the canines
Six years old: the hollow under the nippers, called the mark, has disappeared from the nippers, and diminished in the dividers
Seven years old: the mark has disappeared from the dividers, and the next teeth, or corners, are level, though showing the mark
Eight years old: the mark has gone from the corners and the horse is said to be aged.
After eight years, indeed good authorities say after five years, the age of a horse can only be conjectured. Dishonest dealers sometimes "bishop" the teeth of old horses, that is scoop them out, to imitate the mark: but this can be known by the absence of the white edge of enamel which always surrounds the real mark, by the shape of the teeth, and other marks of age about the animal. The wear of teeth may also be affected by diet, natural abnormalities, and cribbing.
Other dental estimators of age
• Cups: are hollow and rectangular or oval in shape, appearing on the tables of the permanent incisors, that wear away over time. In general, cups are worn away on the lower central inscisors by age 6, the lower intermediates by age 7, and corners at age 8. The cups of the upper central incisors are worn away by 9 years of age, the upper intermediate incisors by 10, and the corners by 11. When all the cups are gone, the horse is referred to as "smooth mouthed."
• Pulp mark / Dental star: After some wear has occured on the teeth, the central pulp cavity is exposed, and the tooth is marked by a "dental star" or "pulp mark." These begin as a dark line in front of the dental cup, which grows in size and becomes more oval in shape as the cups are worn away. Dental stars are usually first visable at age 6, on the animal's lower central incisors, and very visable by age 8. They appear on the lower intermediates by age 9, and on the other incisors between the ages of 10-12 years.
• Hook/Notch: A hook appears on the upper corner incisor around age 7, and dissapears by age 8. It reappears around age 13, again dissappearing about 1 year later.
• Galvayne's Groove: The Galvayne's groove occurs on the upper corner incisor, producing a vertical line, and is helpful in approximating the age of older horses. It generally first appears at age 10, reaches half-way down the tooth by age 15, is completely down the tooth at age 20. It then begins to dissappear, usually half-way gone by age 25, and completely gone by age 30.
• Lower jaw shape: Older horses may appear to have a lean, shallow lower jaw, as the roots of the teeth have begun to dissappear. Younger horses may seem to have a lumpy jaw, due to the presence of permanent teeth within the jaw.
• Angle and Shape of the incisors: As the horse ages, the angle of the incisors generally becomes more acute, slanting forward. The incisors gradually change their form as the horse ages, becoming round, oval, and then triangular.
