A HORSES MOUTH

Straight from the Horses Mouth

When a wild horse is hungry, he goes to a place where there is grass to eat and then he puts his nose down and begins tearing off the blades. To do this, he uses his upper lip to grasp a group of blades; his tongue to orient the blades as they come into his mouth; and his jaw muscles and incisor teeth to grasp and pinch the blades. With an abrupt, obliquely-backwards motion of the head, he then tears off the blades.

Once the blades are torn off, the horse uses his tongue to hold the wad of food against the cheek teeth on one side. A horse’s chewing motion is normally not up-and-down, but outside-to-inside on a slant determined by the slant of the matching surfaces of the upper and lower cheek teeth. Repeated chews work the mass into a spiralling, cigar-shaped wad. Blades get chopped finer and finer as they work their way down the cheek battery from front to rear, and are then swallowed.

Chewing action thoroughly mixes the chopped blades with saliva, which is the first digestive juice. (It’s important not to forget that the oral cavity is the first part of the horse’s digestive system).

After chewing and swallowing a segment of one “cigar”, the horse lowers its head to bite off another bunch of blades. The next mouthful may be chewed on either the right or left side, but horses can chew on only one side of the mouth at a time. A normal horse distributes the effort evenly.

Why Your Horse Needs Dentistry

Your horse lives under conditions quite different from those found in the wild. Artificial conditions which impact your horse’s mouth are:

• He lives inside a fenced area.
• Most of his diet is made up of processed feeds (grain and hay)/ or soft pastures.
• He is not able to graze outside twelve+ hours per day.

Radio-tracking studies of mustangs show that the animals travel an average of thirty to forty miles per day throughout the year. They do this as a natural consequence of their search for food and water. The impact of fences (confinement) on domestic horses has often been documented -- for example, on stress levels, on the condition of their feet and legs, and on parasite loads. Fences enclosing groups of horses often create dry lot conditions under which there is little or no plant material available to graze. This makes feeding hay and grain necessary.

• How does this impact your horse’s teeth?

• Although processed feeds still give your horse’s cheek grinders a workout, he does not use his incisors to tear off stems of hay or pellets. His incisor teeth thus receive no wear as the horse brings the food into his mouth. Over time, this results in failure of the horse’s incisors to keep pace in wear with the cheek teeth. The incisors may become so long that they partially or totally prevent the cheek teeth from touching. This in turn makes it impossible for your horse to chew his food properly. And that, in turn, can have some really horrific consequences, including:
  
  
• Temporo-mandibular (TM. or jaw joint) pain, causing the horse to be difficult or unsteady on the bit.
• Various forms of snaggle-toothed or wave mouth, causing uneven chewing pressure and the development of sharp hooks at the fore and aft ends of the cheek tooth batteries. Hooks & other protuberant can eventually become so long that they gouge the gum, creating abscesses and pain. Irreparable damage may result.
• Sharp points on the inner and outer edges of the cheek teeth. Points cause cheek and tongue abrasions, and again the tendency to fight the bit.
• Failure to properly grind food, resulting in significant waste of food, and more seriously, in increases in the frequency of colic. (In order for horses to absorb water and nutrients in the gut, a mush of chopped grass blades must be continually present there, not long unchewed stems balled up like twine).

The decayed tooth is clearly visible. The large molar (right) need to be filed down, or floated, at regular intervals or they interfere with the horse's chewing.

Equine Digital Radiography