Rostral and caudal hooks are dental abnormalities that can limit performance, cause weight loss, lead to sinus infections and even result in the death of your horse.
Rostral hooks are defined as overgrowth of the number 06 premolars. The number 06 premolars are the first large cheek teeth in the mouth. It is more common for the upper premolars (106 and 206 premolars) to develop large hooks. Caudal hooks are defined as overgrowth of the number 11 molars. The number 11 molars are the last large teeth in the back of the mouth. It is more common for the lower molars (311 and 411 molars) to develop large hooks.
|Rostral Hook||Caudal Hook|
Cause: Rostral and caudal hooks are caused by discrepancies in the length and position of the maxilla (upper jaw) and the mandible (lower Jaw). If the maxilla and mandible do not match, then rostral and caudal hooks soon develop. It is more common for the maxilla to be longer than the mandible. The incisors or front teeth present as the classic overbite.
Clinical signs: Diagnosis is made by visual inspection. For rostral hooks, when looking inside the mouth the first large check teeth will have grown down much further than the other premolars. Sometimes it is easier to see rostral hooks when looking across the mouth: look at the horse's right tooth while standing on the left side of the head. Caudal hooks can only be visualized with a speculum that allows you to see the last molar in the back of the mouth. Be aware that some horses can have rostral or caudal hooks without the classic overbite or underbite.
Initially rostral and caudal hooks will manifest as performance and bit problems. Your horse may resent the bit in one or both directions. The rostral hooks can pinch soft tissue. The caudal hooks can cause severe soft tissue damage. The hooks will limit rostral and caudal slide of the mandible which will make it painful for the horse to put his head down and travel collected. This is especially important in horses that wear a nose band which prevents them from opening their mouth. These poor horses have no way to compensate for the lack of normal mandibular movement. Many horses start to throw their heads to avoid pain.
Limiting rostral and caudal slide will also interfere with mastication. Improperly chewed food will not be digested correctly and your horse will lose weight. He may drop feed as he chews or you might see undigested feed in the feces.
Eventually caudal hooks can become large enough that severe soft tissue and bony damage occurs. A hole in the maxilla, called an oromaxillary fistula, can develop as the overgrown tooth drives into the opposite bone. Feed material is pushed thru the hole and into the paranasal sinus. That leads to sinusitis, severe sinus infection, and even death.
Treatment: Fortunately complications stemming from rostral and caudal hooks can be avoided. Simply have your veterinarian check your horse's teeth twice per year.
|Cutting Caudal Hooks||Dentistry by Veterinarian|
I like to check my patient's teeth when I vaccinate. If your horse's teeth need dental maintenance; have it performed by a licensed equine veterinarian with equine dentistry experience and the right dental equipment. You can review this case study to learn the experiences of one patient in the treatment of rostral and caudal hooks.
If you need your horses teeth evaluated or have other dental needs please contact Conley and Koontz Equine Hospital at 877-499-9909. If you would like to read a personal perspective about how severe caudal hooks affected a mini donkey, see this blog by Dr. Koontz.
Robert H Koontz DVM
Chief Executive Officer
Conley and Koontz Equine Hospital