Okanagan Equine provides full service dentals, usually under standing sedation and with both power and hand tools as needed.

Equine dentistry is a required part of your horse’s routine health maintenance that includes annual vaccinations, internal and external parasite control, as well as regular farrier care. There are basically two reason why dental care is required in the modern horse. One is for health reason and the second is for improved performance while using the horse.

A regular oral examination with dental treatment is necessary because of the anatomy of the horse’s mouth and the rations we feed to the modern horse. Research has shown that regular dental imbalance corrections and maintenance improves feed efficiency by 10-35% and that it can extend the useful life of the teeth by 5-10 years. This is one of the reasons we now see horses living to 25 or 30 years or more in good health. It is very good value for veterinary dollars.

Not all horses with dental issues show clinical signs of a problem. A regular plan for oral examinations and treatments should be included in basic health maintenance for your horse.

The anatomy of the horse's teeth is that the upper cheek teeth (molars and premolars) are set wider apart than the lower cheek teeth.

Anatomy-Head-SideView

1-1

There is very little overlap of the chewing surfaces at rest, and there would be little contact of the chewing surfaces if the horse chewed up and down, like people do. Horses have to chew side-to-side to get good occlusion or contact with upper and lower cheek teeth. Horses can chew on only one side of their mouth at a time.

The anisognathic (unequal) position of the upper and lower rows, or arcades, of teeth, plus side-to-side chewing causes the chewing surface of the teeth to wear at a 15 degree angle and allows sharp enamel points to develop on the lingual (cheek) side of the upper cheek teeth and the buccal (tongue) side of the lower cheek teeth.

1-2

The horse opens the mouth slightly, moves the jaw to one side. As the mouth closes the chewing surfaces shear off or mince food. The mobile mandibular arcade (jaw cheek teeth) grind feed against the fixed (upper) maxillary arcade. As the jaw returns to the resting position, the chewing surfaces separate. The cheek teeth on either side should be used fairly equally. The coarser the feed, the more extensive the jaw motion becomes. When the front teeth, or incisors are in contact, there should be no contact between the upper and lower molar arcades.

 

1-3

As a result of this anatomy of the chewing motion and the fact that processed feed has increased as a portion of the ration, all horses develop sharp enamel points on the outsides of the upper cheek teeth and the insides of the lower cheek teeth. To fully utilize feed, the horse’s entire cheek teeth arcades must be in contact when chewing to provide the required shearing and grinding of feed. Horses that are fed a ration that contains more processed feeds do not have the same chewing motion, and as a result tend to develop enamel points more rapidly than free-ranging horses. The chewing motion in a horse requires good side-to-side and front-to-back mobility. Any malocclusion that is present restricts the lateral motion required for effective chewing, and tends to accentuate any pre-existing problems.

Not all horses with malocclusion problems show clinical evidence of it. Horses adapt to chronic discomfort and pain and may just eat slower. Some of the signs of dental problems are:

Some clinical indication of possible dental disease:

  • Weight loss over a period of time while eating quite well
  • Don’t chew long enough ( bolts food )
  • Slower or prolonged chewing ( slow eater )
  • Drops excessive feed or half-chewed feed
  • Excessive salivation ( drools )
  • Elects to eat a portion of hay ration before grain (packing cheeks )
  • Tilt head to one side or shakes the head while eating
  • Sore developing on the tongue, lips or gums
  • Manure contains long ( ????cm/in ) pieces of poorly chewed up hay.
  • Bad odor from muzzle

While riding you may notice:

  • No bend or suppleness of the neck
  • Resistant to bridling up and collection
  • Tend to pull the muzzle up and out of turns
  • Excessive bit activity
  • Rearing and exaggerated response to bit pressure

Which horses need dental examination and how often is open to debate. All horses, not just horses that display signs of dental disease, require dental treatment at a regular interval. One of the most damaging myths about horse care is that your horse will show outward signs when it has sharp points or malocclusions in their mouth. This is not always the case. Cheek teeth erupt at approximately 4-6 mm annually resulting in significant enamel points within a year. By the age of 5 years all the permanent teeth are in wear and every horse should have had at least one thorough oral examination under sedation to identify those with malocclusion problems that will require closer follow up. It is also best to catch a dental problem when the horse is young as many serious malocclusions can be remedied if identified early. Sedation allows for a more protracted visual examination and allows digital palpation of the teeth and oral cavity. Manipulation of the mandible to assess cheek teeth occlusion is much easier and more informative under the relaxation sedation provides. All horses over two years of age would likely benefit from an oral examination with a dental float (sharp enamel points and developing transverse ridge reduction) if they haven’t been done in the past six months. Saddle horses and performance horses in work require annual dentals not only from the aspect of improved health and longevity, but because a balanced mouth improves performance and suppleness while under tack. For high-level performance horses, biannual enamel point reduction dentals provide the highest comfort level for the horse. There are obvious benefits to doing a dental float on young horses entering training. The upper cheek teeth in young horses tend to be softer and develop large, very sharp enamel points that can be a real source of pain when external pressure from a halter or head stall is applied. A bit also alters the commissure (corners) of the mouth, so tissue can impinge on the front of the teeth and cause pain. Horses that are retired or out of work and have no recurring malocclusion problems may only need to be examined every two years.

Common Equine Dental Malocclusion

Note:  All abnormalities impair the side-to-side chewing motion that horses require.  It never gets better, only progressively gets worse.

Molars & Incisors

CAUDAL HOOKS

CAUDAL HOOKS

Definition - Dominant lower or upper last molar overhanging opposing molar.
Etiology - Hereditary - May result from horse born with over or under bite. Developmental - May result secondary to molar malocclusion that forces jaw out of alignment.
Resulting Problems - prevents horse from chewing freely side to side resulting improper and excessive molar wear. Tight soft tissues are very susceptible to lacerations from sharp molar points. Can cause extreme discomfort as head carriage or frame is changed when riding.
Solution - Reduce dominant molar to prevent excessive wear to opposing molar and carefully round to prevent soft tissue trauma.

ROSTRAL HOOKS

ROSTRAL HOOKS

Definition - Dominant upper front premolars overhang lower premolars.
Etiology - Hereditary - May result from horse born with an overbite. Developmental - May result secondary to molar malocclusion that forces jaw out of alignment.
Resulting Problems - Prevents horse from chewing freely side to side resulting in improper and excessive molar wear. Can cause excessive wear to opposing lower premolar. Can cause severe bit problems and trauma to soft tissue.
Solution - Reduce dominant portion of upper premolar, rounding unopposed portion of premolar smoothly toward gum. Requires preventative maintenance to prevent reoccurrence.

RAMPS

RAMPS

Definition - Excessive height to lower premolars.
Etiology - May occur when upper from premolar deciduous cap, or baby tooth is retained preventing normal growth of permanent premolar. Can occur if a tooth is reduced without corresponding correction to opposing tooth.
Resulting Problem - Prevents horse from chewing freely side to side resulting in improper and excessive molar wear. Can cause severe discomfort with the bit. Can force lower jaw forward over time causing under bite.
Solution - Reduce dominant tooth to allow opposing too the recover over time.

ENAMEL POINTS

ENAMEL POINTS

Definition - sharp points that generally form on the outside of the upper molars and the inside of the lower molars.
Etiology - Occurs over time as horse stops chewing as far sideways resulting in unopposed edge tooth getting longer and the enamel forms razor sharp points.
Resulting Problem - Enamel points traumatize soft tissues causing pain and discomfort when eating and also from bits and other head gear pulling cheeks and tongue into these areas. Also stops horse from chewing freely sideways.
Solution - Remove sharp enamel points.

SHEARED MOLAR TABLE

SHEARED MOLAR TABLE

Definition - Extreme angulation of chewing surface of molars.
Etiology - Results from lack of lateral excursion or side to side chewing.
Resulting Problems - Very severe problem. Does not allow horse to chew sideways resulting in very poor utilization of feed.
Solution - Correct molar table angle of upper and lower molars over time allow horse freedom to chew side to side.

WAVE COMPLEXES

WAVE COMPLEXES

Definition - Molar arcade develops an uneven "wavelike" appearance generally involving many premolars and molars.
Etiology - Often occurs secondary to other malocclusions such as retained deciduous caps, missing teeth, hooks, ramps, etc. Results from horse being unable to obtain free side to side chewing.
Resulting Problems - Causes gradual excessive wear to many molars, resulting in prematurely worn out teeth, periodontal pocketing, decay and loss of teeth. Prevents free side to side chewing and inhibits proper grinding of feed.
Solution - Reduce high complexes to allow recovery of opposing teeth and allow freedom to chew freely side to side to encourage proper use. Requires preventative maintenance over time.

STEPPED MOLARS

STEPPED MOLARS

Definition - Molar arcade develops stepped-like appearance.
Etiology - Most often occurs due to a missing tooth allowing the opposing tooth to grow into the void. Can occur from extreme uneven wear. May occur when a deciduous cap or baby tooth is retained too long delaying normal growth of permanent tooth and allowing opposing tooth to grow too long.
Resulting Problems - Prevents or blocks the horse from being able to chew freely resulting in uneven and improper wear to molars and incisors.
Solution - Reduce high molar to allow freedom to chew correctly. Requires maintenance to prevent unopposed tooth from growing into space.

ACCENTUATED TRANSVERSE RIDGES

ACCENTUATED TRANSVERSE RIDGES

Definition - Enlarged ridges that run across chewing surfaces of molars.
Etiology - Can result from a shift in jaw alignment. Forms from a harder area in one tooth over powering and wearing into a soft area in an opposing tooth. also can occur if horse is not chewing in proper sideways motion.
Resulting Problems - Interfere with normal chewing and jaw motion front to back. Cause excessive wear to opposing molars. Can result in severe periodontal disease and diastema.
Solution - Reduce enlarged ridges to allow opposing teeth to recover and horse to chew correctly. Will improve when existing malocclusions are corrected.

PERIODONTAL POCKETS

PERIODONTAL POCKETS

Definition - Gum disease around tooth causing an area for feed to pocket. Etiology - Results from malocclusion or misalignment of teeth. Progresses as horse is unable to chew correctly.
Resulting Problem - Gum disease leads to bone erosion around teeth and eventually can cause infection, abscess and loss of tooth.
Solution - Correct malocclusion as early as possible. Very difficult to stop progression of periodontal disease if it is not stopped early on. Prevention is the key.

DIASTEMA

DIASTEMA

Definition - Space that occurs between two adjoining teeth.
Etiology - Often results as malocclusions force two teeth apart over time.
Resulting Problems - Causes feed to get trapped between teeth resulting in progressive and severe periodontal disease. Results in overall poor oral health.
Solution - Very difficult to correct. Reduce unopposed overgrowth of opposing teeth. Prevention of malocclusions in th key.

OVERBITE

OVERBITE

Definition - Upper incisors protrude in front of lower incisors.
Etiology - Hereditary - Horse may be born with an overbite. This will often result in rostral and/or caudal hooks. Developmental - Rostral and/or caudal hooks can shift alignment of bite resulting in an overbite.
Resulting Problem - Prevents horse from chewing freely side to side resulting in improper and excessive molar wear. Rostral and caudal hooks, transverse ridges, wave complexes and sheared molar table angles will become more severe as the horse is forced to chew incorrectly over time. Can also cause severe discomfort with the bit.
Solution - Reduce length of upper incisors. Correct molar malocclusions.

UNDERBITE

UNDERBITE

Definition - Lower incisors protrude in the front of upper incisors.
Etiology - Hereditary - Horse is born with under bite. Developmental - Ramps on lower premolars can cause lower jaw to shift forward resulting in an under bite.
Resulting Problems - Prevents horse from chewing freely side to side resulting in improper and excessive molar wear. Ramps, transverse ridges, wave complexes and sheared molar table angles will become more severe as horse is forced to chew incorrectly over time. Can also cause severe discomfort with the bit. Can result in TMJ pain.
Solution - Reduce length of lower incisors. Correct corresponding molar abnormalities.

VENTRAL CURVATURE (Smile)

VENTRAL CURVATURE (Smile)

Definition - Outer corner lower incisors grow longer relative to outer corner upper incisors.
Etiology - May occur when deciduous caps are rretained onupper corner incisors preventing normal growth of permanent incisors. Can occur due to abnormal chewing secondary to molar malocclusions.
Resulting Problems - Inhibits horse from chewing freely side to side often resulting in improper and excessive molar wear.
Solution - Reduce length of upper central incisors and lower corner incisors to allow free side to side movement.

DORSAL CURVATURE (Frown)

DORSAL CURVATURE (Frown)

Definition - Outer corner upper incisors grow longer relative to outer corner lower incisors.
Etiology - May occur when deciduous caps are retained on lower corner incisors preventing normal growth of permanent incisors. Often occurs from cribbing and wood chewing and can occur due to abnormal chewing secondary to molar malocclusions.
Resulting Problems - Inhibits horse from chewing freely side to side often resulting in improper and excessive molar wear.
Solution - Reduce length of upper corner and lower central incisors to allow free side to side movement.

OFFSET OR DIAGONAL BITE

OFFSET OR DIAGONAL BITE

Definition - Upper incisors on one side of mouth are excessively long and lower incisors on opposite side are excessively long, causing incisors to meet on a diagonal.
Etiology - May develop over time if horse chews more in one direction. Can result from cribbing and wood chewing and may occur secondary to molar malocclusion or as a result of a missing incisor or incisor damage causing opposing incisors to become excessively long.
Resulting Problem - Causes horse to excessively wear molars on one side of mouth and opposite side molars become excessively long resulting in a sheared molar table angle. Can result in TMJ pain.
Solution - Reduce excessively long incisors. Correct corresponding molar mmalocclusions Will need frequent follow up corrections.

BONE SPUR

BONE SPUR

Definition - Mandibular periotitis or abnormal bony growth due to trauma.
Etiology - Most often caused by trauma from bit to lower jaw bone.
Resulting Problem - Can be extremely painful causing behavioral problems when bit contacts area.
Solution - Surgical removal of affected bone.

WOLF TOOTH

WOLF TOOTH

Definition - Small shallow rooted teeth in front of premolars. Most common in upper jaw. Can occasionally occur in front of lower premolars.
Etiology - A normal finding in most horses. May not appear in some horses.
Resulting Problem - Bit may contact tooth causing severe pain and discomfort as tooth moves. Can fracture or become loose causing discomfort
Solution - Wolf teeth should be removed before horse starts being bitted to prevent discomfort and bad habits.

BLIND WOLF TOOTH

BLIND WOLF TOOTH

Definition - Abnormal wolf tooth that does not break through gums.
Etiology - Blind Wolf Tooth usually comes in at an angle, often up to one inch forward of premolars. Angle of tooth does not allow it to penetrate gums.
Resulting Problem - Can cause severe bit problems. In a location that bit often contacts. Often missed due to being buried under gums.
Solution - Generally easy to surgically remove.

About
Okanagan Equine Veterinary Horse Services is located in Kelowna, British Columbia, Central Okanagan. We offer an equine hospital, equine reproduction, breeding and stallion collection plus semen evaluation facility.