Equine Dentistry: The Hook

For years I have had our equine dentist, Sasha Kone, out to our stables to touch base with new horses. She's usually the first healthcare professional I call other than the farrier! Jello, however, missed her initial visit because of the stitches she had in her mouth after her accident this fall that prevented us from doing the dental exam.

Over the months we had her we noticed that she had a number of behavioral issues:

• head shy on one side
• tense and anxious about giving to the bit
• difficulty bending
• not reacting as expected to the bit
• very slow eating

A lot of these behaviors just didn't make sense in terms of who Jello is as a horse. She is way to polite, endearing and willing to assume that they were the result of her just being a jerk!

During her last dental appointment we found out why! Both sides of her mouth were ulcerated and she had terrible hooks on both sides of her mouth.

Rostral hooks are the overgrowth of the front premolars (1/6 or 2/6 tooth). The hooks are caused by discrepancies in the length and position of  the upper jaw (maxilla) and the lower jaw (mandible). When they do not match perfectly, hooks develop. Often, if there is a rostral hook (up in the front, there is a caudal hook (or ramp) that develops in the back of the mouth as well.

Sometimes it isn't the horses conformation, but simply the height at which the horse is fed that causes the mandible and maxilla to be misaligned. If the horse eats off of the ground, then all of the teeth are in the natural position. When a horse is fed up higher, as seen in a lot of show barns using hay feeders, the mandible shifts back, causing the teeth to grid out of occlusion and cause the rostral hooks and caudal hooks.

When horses have hooks, the teeth can no longer grind against one another forward and back, causing the horses to have to chew up and down instead of in their natural griding pattern. It also presents a very large problem for horses needing to release their jaw to the bit, forcing their mouths open with bit pressure instead of allowing them to relax into the pressure of the bit.

Poor Jello!

Parrot Mouth 2: an ongoing observation of Apollonia

Everyone will remember the story of Apollonia from December? If not be sure to CLICK HERE to visit our other blog post about Apple's first dentist appointment to catch up on the story before reading more!

For comparative reasons we are including the photo of Apple's first appointment in December 2013 for comparison. Each photos includes:
PHOTO 1) Natural incisor alignment before the appointment.
PHOTO 2) Incisor alignment after the molar angle has been treated.
PHOTO 3) Incisor alignment after the final stage of the appointment.

Visit 1: December 2013 (Age 7 Months)

Visit 2: March 2014 (Age 10 Months)

Since Apple's first appointment, as we expected her teeth returned to their natural state and her parrot mouth was again evident three months later. This is because the changes that we made to her mouth in December were not structural changes to her bone structure, but just changes in the angles of her teeth causing her jaw to lay in a different position. As the teeth grew and wore, the changes that we made were slowly erased and the teeth again started to fall into their position that shows the overbite.

Not to mention, because of growth spurts that cause the head and jaw to grow at differing paces, Apple's parrot mouth and may continue to enlarge and lessen as she ages. Bone growth in the skull of horses continues for a longer time than much of the rest of the skeletal structure, particularly in the maxilla and jawbone which house the developing and erupting teeth. While most of the growth plates in the distal parts of the limbs (below the knee and hock) are typically fused by age two, the fusion of the higher up joins and vertebral physes, as well as bone growth in the skull, can continue until about age six. For more information about bone growth, see this article by Deb Bennett: http://www.equinestudies.org/ranger_2008/ranger_piece_2008_pdf1.pdf

As shown, this process is not meant to "fix" Apple but to help her live a more normal and comfortable life. It is a continual process that will need to be sustained throughout her entire life. Our goal is to simply make these changes sustain longer between each visit.  

Using similar techniques as last time, you can see that we were again able to give Apple some occulsion - meaning that the incisors touch. This will help her considerably with eating and give her the ability to have at least some wear on her front incisors which is very important to her dental health. 

Parrot Mouth: an ongoing observation of Apollonia

Apollonia (named after the patron saint of dentistry) is a cute little APHA paint baby living at Painted Bar Stables. She was the product of a breeding by their stud and a mare in OH. While her body is very well proportioned and her temperament fantastic, at 2 months of age it was noticed that she had developed a terrible parrot mouth. 

Parrot mouths are not a "genetic issue" from one or both parents. They are the result of a genetic incompatibility between parents resulting on mismatched jaw/head or problems with how the jaw naturally ties into the rest of the skeletal structure of the head. Basically, the mare and stallions heads just do not fit together (Reference:http://evds.net.au/article_parrot_mouth.php).

Because the owner of the foal had exclusively bred for halter - and a parrot mouth eliminates a foal from competition - it was decided that Apple would move to NY to become a trail horse at Painted Bar Stables and a long term procedural example and model for Endless Mountain Equine Dentistry. 

Apple will need regular appointments to continue to correct the angles of her teeth and to encourage proper placement of her jaw. While she may never be fully corrected, our goal is to at least restore some occlusion between her incisors. 

Apollonia: progress at 1st dentist appointment (age 7 months, 1 week)

PHOTO 1:The first photo shows Apple's natural alignment at 7 months & 1 week of age. As illustrated in the photo her top incisors protrude nearly 1" past her bottom incisors providing zero contact and occlusion. As a result both sets of incisors have no wear as they grow and are overgrown, giving a "buck tooth" appearance. 

What you cannot see is that the molars are also not aligned either. As a result large hooks have developed on the top front molars (1/6 & 2/6) and large ramps on the lower rear molars (3/8 & 4/8 - the rest of the molars have not yet emerged. The result is that the entire jaw is locked backward. 

PHOTO 2: The second photo is after molars have been treated. All of the molars have been filed and a new angle has been introduced to the entire surface of the molars, shortening the lower rear molars and the upper front molars to encourage the entire jaw to sit further forward. 

After this procedure, there was still a lack of occlusion of the incisors but the overbite was greatly reduced. 

PHOTO 3:The third photo shows the final stage after this first visit. The incisors have been realigned and shortened to their proper length. 

After this was done the jaw now was able to move forward significantly. While there is still a significant overbite, there is finally the beginnings of occlusion as the incisors touch.

MARCH 2014 UPDATE: http://paintedbarstables.blogspot.com/2014/03/parrot-mouth-2-ongoing-observation-of.html

Equine Dental Emergencies

Today was a quick emergency visit at the Painted Bar Stables from the lovely Sasha Kone of Endless Mountain Equine Dentistry. All three of the horses we worked on today were new horses for that were picked up in 2012 and it seems that none of them had ever had their teeth done in the past.

Joker, a small Morab cross, age ~15, obviously has lived the most traumatic life. In addition to his split tongue (which probably happened years ago due to being tied by the bit and spooking) he also had a raw ulcer in his left cheek and lacerations throughout his mouth from sharp points.

Brumby, an appendix QH cross, age ~7 (who aged in YOUNGER than she had been sold as, when does THAT happen?!) had scaring all throughout her mouth from the points and ridges in her mouth.

Bear, a TB gelding, age 12, who came from a large lesson barn continually lives up to his name "Bad News Bear." He had the worst teeth issues by far. He had deep scarring throughout but also had severe periodontal disease (rotting gums) from a protruding 3/9 wave that had grown so tall it actually fractured the upper 2/9 molar and was worn past the gum line. When we cleaned out the perio pocket there was a significantly foul odor.

THIS IS WHY YOU KEEP YOUR HORSES' TEETH UP TO DATE!!