Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH) is a progressive, painful dental condition primarily affecting the incisor teeth of older horses, typically those over 15. The disease involves two distinct processes: the internal breakdown of tooth structure (resorption) and the abnormal, excessive formation of dental cementum around the tooth roots (hypercementosis). This syndrome destabilizes the teeth and causes chronic inflammation, leading to severe oral discomfort. Because the onset of EOTRH is gradual, it is frequently overlooked until the condition has progressed significantly, often due to the horse’s tendency to hide pain.
Recognizing the Signs of EOTRH
Owners may first notice EOTRH through changes in their horse’s behavior, particularly when interacting with the muzzle or food. A common sign is a reluctance to bite into hard treats like carrots or apples, or a tendency to drop feed, which is known as quidding. Horses experiencing incisor pain may also exhibit sensitivity when being bridled or when a hand touches the muzzle area.
Changes in grazing behavior are also significant indicators, as the horse uses its incisors to clip grass. Affected horses may graze less efficiently or change their head posture while eating. Head shaking, hypersalivation, or bad breath can be further clues that a painful process is occurring in the front of the mouth.
Physical signs become visible as the disease advances, beginning with inflammation of the gums, which may appear noticeably red and swollen (gingivitis) around the incisors. The gum line may appear uneven or receded, making the teeth look longer than usual. In later stages, the roots of the teeth can develop a bulbous appearance due to the hypercementosis, causing a noticeable bulge along the gum line.
Advanced cases may involve small red dots (petechiae) on the gums, or the development of pus pockets and draining tracts above the affected incisors. Teeth may become mobile or fracture easily, indicating significant structural compromise. These signs signify chronic oral pain and require immediate veterinary consultation.
Professional Confirmation and Staging
A definitive diagnosis of EOTRH requires a comprehensive oral examination by a veterinarian, often performed under standing sedation for patient comfort and thoroughness. During this initial exam, the veterinarian will carefully probe the gingival sulcus, which is the space between the gum and the tooth, to assess for deep pockets, inflammation, and sensitivity. The incisors will also be gently tested for abnormal mobility.
Confirming EOTRH requires obtaining dental radiographs (X-rays) of the incisor teeth. External examination alone is insufficient because the destructive changes occur below the gum line, within the tooth roots and surrounding bone. Radiographs allow the clinician to visualize the internal structure, clearly showing areas of resorption and hypercementosis.
Radiographic imaging is also used to stage the disease, which determines the most appropriate course of action. Staging systems categorize the severity of internal changes, such as resorption or hypercementosis, often on a scale from 0 to 3. This staging helps the veterinary team identify exactly which teeth are affected and guides the treatment plan.
Management and Treatment Options
Treatment for EOTRH is dictated by the disease stage and the degree of pain experienced by the horse. Mild or very early cases may initially be managed with palliative care focused on comfort and monitoring. This can include the use of non-steroidal anti-inflammatory drugs (NSAIDs) during flare-ups and dietary modifications, such as soaking feed to make it softer and easier to pick up.
Since EOTRH is a progressive condition with no known method to reverse the damage, surgical extraction of the affected teeth is the definitive and most effective treatment for moderate to severe cases. Extraction eliminates the source of chronic pain and inflammation, offering immediate and lasting relief. The procedure is typically performed with the horse standing and heavily sedated, using local anesthesia.
The number of teeth extracted depends entirely on the radiographic staging, ranging from a single affected tooth to a full removal of all incisors. While the prospect of incisor removal can be concerning for owners, horses adapt remarkably well to the loss of their front teeth. They use their lips and tongue to effectively grasp hay and grain, and they quickly learn to graze even without incisors.
The prognosis following extraction is excellent, with most horses showing significant improvement in attitude, appetite, and overall quality of life. Post-extraction care involves a short period of soft feed and pain management. Horses typically return to normal activities, including grazing, within a few weeks, and owners often report their horse seems happier and more energetic.