Understanding the challenges of Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH)

As horses progress into their senior years, it is important to have regular dental checks to ensure their overall health. Unlike in humans, horse teeth continue to grow throughout their lifespan, and older horses in particular can develop painful issues that can affect their overall demeanor. 

Equine odontoclastic tooth resorption and hypercementosis (EOTRH) is a condition that can affect horses as they age. Destruction of the tooth structure and abnormal, excessive cement accumulation can lead to excruciating oral pain. Knowing about this condition and fully understanding its progressive nature is important for everyone involved in the care of horses to ensure timely intervention and care of affected horses. 

EOTRH primarily affects horses over the age of 15.  Certain breeds such as thoroughbreds and warmbloods are more susceptible, although it has been diagnosed in other breeds. Geldings are also noted to be more susceptible than mares. Diet, overall health, and dental care can all influence the progression of EOTRH. 

In the early stages of the disease, it can easily go unnoticed. Some horses may exhibit bad behavior, particularly with regard to accepting the bit due to oral discomfort, which can have a knock-on effect causing headshaking or head tilting. 

As the disease progresses the horse may start to lose weight, have difficulty chewing and may emanate a foul odor from the mouth. Visual indicators include gingivitis (irritation, redness and swelling of the gums), gingival hyperplasia (gum recession), draining fistulas (a canal that develops to drain infection from an abscess) along the gum line, wobbly or missing teeth and tooth fractures. 

The process to diagnose EOTRH starts with a physical exam by a veterinarian and dental radiographs, or in some cases computed tomography (CT) imaging. The incisors, and on occasion, the canine teeth can be affected. This condition causes resorption of tooth structures by cells called odontoclasts, which leads to destruction of the horses’ dental tissues. At the same time, abnormal amounts of cementum accumulate around the roots of the affected teeth. This results in the teeth enlarging ultimately compromising the structural integrity of each tooth. 

Early stages of the disease can be managed with regular floating but in most cases, it is necessary to remove the affected teeth, as the disease is progressive and there is no known cure (other than extraction).

“Extraction of the affected teeth will alleviate discomfort and prevent further complications. Horses typically respond very well to complete incisor extractions, recovering their appetite quickly after surgery” explains Sophie Boorman, clinical assistant professor of equine surgery. 

The Marion duPont Scott Equine Medical Center (EMC) has state-of-the-art equipment, diagnostic imaging capabilities, and the expertise to diagnose and treat complex dental-related problems in the horse. 

The EMC’s Pegaso Computed Tomography (CT) scanner has revolutionized imaging capabilities for dental-related issues and provides bone and soft tissue images to aid in the accurate diagnosis of the most complex equine dental issues. 

Building a good relationship with a veterinarian that specializes in dental care and treatment is important. Every horse should have their teeth examined regularly and with routine floating, which can help in the identification of dental issues before they become problematic.