OLDER horses often have their own particular set of health issues, especially when it comes to dental problems.

Horses live by their ability to chew. Chewing food properly allows a horse to absorb the nutrients and minerals needed to maintain weight, keep a balanced metabolism, have energy, and generally stay well.

Therefore, maintaining a healthy mouth that can chew efficiently is crucial, especially as a horse ages.

Horses’ teeth are hypsodont in nature (meaning long-crowned). Humans, dogs and cats are brachydont or short-crowned. Most of a horse’s crown is below the gum line and consists of reserve crown contained within the dental socket in the bones of the upper and lower jaws.

Teeth emerge slowly from the socket at a rate of about 3-5mm each year as it ages. In old age the crowns of a horse's teeth are short and they gradually lose their attachments to the tooth socket. In very old age, they eventually fall out.

The goal of preventive equine dentistry is to maximise the life of the tooth by preventing premature wear and disease. Some dental problems found in older horses are correctable, but others are not and must be managed. Diet changes may be necessary to help older horses chew more easily and get the maximum benefit from feed.

Dental discomfort

in horses:

Horses can show many different symptoms of oral pain, some of which may not appear to have anything to do with their mouths.

Many problems begin with mild symptoms that can change completely as disease or abnormality progresses. So, just because a horse is in good body condition and is eating well doesn’t mean that the mouth shouldn’t be checked regularly.

Severe malocclusions:

Severe malocclusions (meaning that the teeth do not meet together for chewing) are usually caused by poor preventive care or lack of preventive care in a horse’s earlier life.

Severe malocclusions (such as a wave or shear mouth) inhibit the horse’s ability to chew food. This will then lessen the ability of the digestive system to extract nutrients and energy from the feed.

Malocclusions can occur in both the incisors (front), and the molar and premolar teeth along the sides of the horse’s mouth.

Fortunately, corrections of waves or ramps or exaggerated bite problems in older horses can be corrected by appropriate dentistry. The objective is to make the horse more comfortable by providing the maximum surface area of tooth for chewing food.

The corrections may be made in two or more treatment sessions, so as not to potentially worsen the horse’s ability to process feed.

Severe conditions require regular corrections, usually every six months for a period of a year or more and may never be completely corrected due to the lack of remaining tooth length available for eruption.

It is important to remember that older horses generally have more fragile mouths than younger horses.

Some may consider discontinuing having work done on older horse’s teeth in an effort to prolong the life of whatever teeth may remain.

However, the best approach is regular check-ups, prompt identification of any problems and often a ‘less is more’ type attitude when conducting any work on the teeth themselves.

Periodontal disease:

This term refers to any inflammation of the tissues that support the teeth, like the gums, the periodontal ligaments, and the alveolar bone sockets.

Periodontal disease can begin in a younger horse. It is a progressive disease that develops over a period of time, beginning with mild gingivitis (inflammation of the gum).

If this is left untreated, it can progress to a more severe stage seen as receding gums and exposed reserve crown and tooth roots and infection. Infection may require tooth extraction.

Periodontal disease can have many causes, including: poor preventive maintenance during the horse’s life and food packing into spaces between the horse’s teeth (diastemata), which allow bacteria to flourish.

If an older horse develops periodontal disease, a few limited treatment options are available.

In cases of diastemata, the aim is to completely clean out any food packing and bacteria and in some cases to widen the gap even further so feed can no longer get stuck in the space. The more advanced cases of disease seen in elderly horses may require tooth extraction.

No research has been done to prove that horses experience many of the adverse systemic reactions to an infected mouth that are seen in other species-such as heart, liver, and kidney problems. However, untreated inflammation and infection can be painful, so addressing periodontal disease is a must in keeping the older horse fit and well.

Loose/worn

or missing teeth

Horses’ teeth can become loose for many reasons such as trauma to the mouth; issues with the supporting structures (as with periodontal disease) and short roots due to old age.

By the time a horse is in his 20s, he may have less than 2cm of tooth left. Without a firm anchor, these teeth can become loose or even fall out.

In younger horses, loose teeth will sometimes re-seat themselves and establish connections within the tooth socket.

In older horses, it’s best to extract these loose teeth. Since an extraction will leave a hole where the tooth was, it’s important to have its mouth examined regularly afterwards.

Food can pack into these spaces and the opposing teeth can overgrow when they have nothing to wear so will usually have to be burred down to maintain bite and chewing motion.

Diet modifications

Keeping an eye on how an older horse chews can help decide when the time is right to modify diet to accommodate dental issues.

Even if dental maintenance has been to a high standard throughout a horse’s life, they still may require a special diet to allow maximum nutrition absorption.

All major feed manufacturers produce pelleted foods formulated specifically for senior horses. These soft, pelleted diets are easy for elderly horses to chew and can sometimes be used as the main food source, removing hay entirely.

Offering hay to older horses with poor dental health can cause even more problems as if a horse swallows enough hay without chewing it well, it can cause impaction colic or choke to occur.

It is important to make diet changes only after consulting with a veterinary surgeon or equine nutritionist.

Clinical signs of dental disease

1. Quidding (dropping rolls of chewed up food)

2. Facial swelling/food packing

3. Malodour from mouth

4. Nasal discharge (usually one sided)

5. Weight loss

6. Colic

7. Choke

8. Abnormal head carriage

9. Head shaking

10. Bitting issues

Dental conditions most commonly seen in older horses are: severe malocclusions, periodontal disease and loose/worn or missing teeth.