Sharp enamel points

When horse have impaired mandibular excursion (and nearly all present day horses do) then they develop sharp enamel points on the lingual edges of the lower molars and the buccal edges of the upper molars. If left untreated these points can cause deep, painful lacerations and ulcers on the lips and cheeks. This will cause the horse great discomfort whilst chewing and also serious interference with the bit, as the bit will press the lips against the sharp points and press the points of the teeth further into the ulcers – OUCH! This is why it is so important to have your horse’s teeth floated regularly. We recommend that horses older than 6 get their teeth floated at least annually, and horses younger than this need much more frequent check ups due to their teeth being much softer and faster wearing, and due to the many changes that occur in the young horse’s mouth with new eruptions and shedding of baby teeth. The frequency of dental treatment required will depend on the diet of the horse and whether the horse is being ridden/driven

Rostral or Caudal hooks

Overbite is a condition whereby the the horse presents with rostral hooks on the first upper molars and caudal hooks on the last lower molars. If left untreated the hooks can become so extensive that they can grow down into the lower jaw causing extreme pain and osteomyelitis in the soft tissue and bone of the opposing jaw. When severe, these require careful reduction under sedation. Cutting with shears is NOT something that is recommended as this could cause pulpar exposure which can lead to severe pain and infection. If the overbite is mild it can be reduced gradually over time and managed with each dental visit without complications. Overbite can be caused by feeding the horse from a raised feeder. As horses are meant to graze from the ground, the gravitational pull on the mandible is altered when they graze with their heads in a raised position. This causes the mandible to be slightly caudally re-positioned and causes the 106 and 206 to no longer be in occlusion with the opposing teeth. Once hooks have formed then the mandible stays in the caudal position as the first molars prevent it from being in its correct position, unless they are corrected by a qualified equine dentist.

Retained caps

In domestic horses, deciduous (milk) teeth can remain attached to the permanent teeth after they have erupted. This is very common in stabled horses such as racehorses. A cap on the tooth can partially detach or rotate, either causing sharp pain by digging into the cheeks or tongue, or trapping decaying feed underneath them. These caps need to be removed if the permanent teeth are beyond the gum line, and this is usually a painless procedure that can be performed without sedation. By removing these caps in time the permanent teeth may erupt normally and there should be no displacement or overcrowding of the permanent teeth. Incisor caps can be trickier to move if they are not mobile, and may need elevation to remove them which will need to be performed under sedation. Horses begin to lose their baby teeth from age two and a half and lose their last incisor caps at four and a half, meaning that they will need more regular dental treatment during this time.

Step mouth

This is a condition where the teeth along the arcade are at different levels, and there may be a “jump” in height from one tooth to the next. This most commonly occurs mid arcade where the molars and premolars meet. This can be caused by maleruption of the temporary molars, the greater wear to one or more teeth due to a fracture or loss of the opposing tooth which can cause a tooth to erupt very quickly as it has nothing to wear against, and then the tooth becomes very long. This can cause a lot of problems for your horse, if the longer tooth meets the opposing arcade at an interdental space then it can act like a wedge and force the opposing teeth apart, creating a diastemata (space between the teeth) where feed will pack and if not treated will lead to periodontal disease which can mean loss of teeth. If the opposing tooth is missing and the tooth in question is left to erupt untreated then it can dig into the opposing jaw causing painful indentations or osteomyelitis in the soft tissue and bone. This condition can severely effect mastication (chewing) and food intake. It is important to get this condition treated by a highly skilled dentist.

Wave mouth and Serrated mouth

Serrated mouth is a condition whereby the molar occlusal surfaces develop a linguobuccal serration so that the tooth surfaces basically zig zag up and down along the arcade. This condition is caused by a diet high in cereal grain and short fibre such as oats, pellets and chaff, and a lack of long fibre such as hay and grasses. Consequently this condition is very common in stabled racehorses and trotting horses. The serrated bite becomes increasingly pronounced as the horse is stabled for longer periods of time. This condition can impede chewing efficiency and speed, increases the chances of feed packing between the molars and increases the likelihood of sharp points on the edges of the teeth which lead to lacerations of the cheeks and tongue. This condition can be countered or managed with regular dental care and the increased provision of long fibre such as hay.

Wave mouth is a condition usually caused by improper filing over time and causes the teeth to undulate along the arcade in a wave-like fashion. It can be caused by the same conditions as step mouth but is a less severe manifestation of these factors. If left untreated this can develop into step mouth. In some cases the teeth may even be worn away to the level of the gums. This is another reason why it is so important to choose a highly trained dentist to treat your horse, as an untrained dentist can cause much more harm than good, and sometimes damage done is irreversible!

Periodontal disease

Periodontal disease is an inflammation of the gingiva (gums) which progresses down into the tooth socket and bone, causing loosening of the periodontal ligament (which attaches the tooth to the bone). The more the disease progresses the looser the attachment becomes, eventually leading to loss of the tooth. Periodontal disease begins when bacteria in the mouth proliferate around the teeth and gums. This bacterial overgrowth can be caused by a diastemata (gaps between the teeth) or perhaps a retained milk tooth, as feed can trap in these spaces and become lodged. Unless this area is cleaned out by a dentist, the feed begins to rot and break down and causes and infection to manifest in the gums. It can also be caused by a build up of plaque around the teeth. The body’s defences are overwhelmed by the massive numbers of bacteria attacking the gingiva and this leads to inflammation. This is called gingivitis and is the first stage of periodontal disease. As the gum becomes inflamed it can swell and bleed, allowing the bacteria to enter the bloodstream and travel around the body, so periodontal disease can affect all areas of the body – not just the teeth! There have been links found between periodontal disease and heart disease, and also links to reproductive problems such as abortion and low birth weight. So make sure you horse receives regular dental care to avoid the development of periodontal disease.

Wolf teeth

Wolf teeth are vestigial molars. That means they no longer have a useful function as a tooth. They usually grow tight against the first molars, but have shallow roots and thus a bit pressing against these teeth loosens the tooth in the gum and causes inflammation and discomfort, causing the horse to react as if it had the wrong bit in its mouth. The problem is made worse if the wolf teeth are vestigially displaced, meaning they grow further forward and thus are in effect "Stand Alone" teeth without even the molars to support them. A bit moving up in the horse's mouth will always loosen these teeth and cause the horse pain as these teeth are then loosened in the gum and the roots become inflamed.

The best option is to remove these wolf teeth as early as possible. This can sometimes be done without sedation when the teeth are small with little root structure, however if they are large and have a substantial root structure then your horse will need a light sedative to assist with removal.

Equine Odontoclastic Tooth Reabsorption Hyperzementose (EOTRH)

EOTRH has started being a problem over the last two years; the vets are doing a lot of research but they are still not 100% sure what’s happening exactly. Around 5-10% of horses in the 17 plus age group are exhibiting signs of the condition and it is mainly found in Icelandic ponies, Norwegians, Welsh ponies and Quarter horses; rarely in Warmbloods or thoroughbreds. Most of the infected ponies have had problems with Cushings or Founder beforehand, so it seems to be a kind of metabolic disease. When EOTRH occurs there is a dissolving process of the tooth roots happening in the front part of the jaw – incisors and canine teeth. As a result of this process the immune system starts storing calcium around the roots which makes the tooth root bulky and destroys the bone around the root channel. The horse’s jaw swells up massively and there are lots of little channels in the gum where pus can be seen and you can see how the inflammation works its way through the jaw. So far vets have tried to treat it with antibiotics and cortisone, but that’s only a short term pain relief. If vets and dentists are able to diagnose the condition early enough there is a Chinese herbal mushroom powder mix which keeps the inflammation down, but the main relief for the horse is to take out the incisors/canines. Once these are removed t it only takes 2-3 weeks until the inflammation and swelling disappears and it is healed off. With the incisors removed, horses can return to normal mastication.

Lacerations or Foreign objects

Lacerations can occur in the mouth as a result of sharp points on the edges of the teeth wearing away at the sensitive mucosa of the mouth. Once lacerations or ulcerations are present they will remain until the source of injury is dealt with. Longstanding ulcerations and lacerations can become infectious, and are very painful for horses, affecting his ability to eat, perform when ridden and his temperament. Lacerations can also be caused by foreign objects, such as when the horse gets a chain or lead rope in his mouth and pulls. I have treated many horses with severe lacerations around their mandible and maxilla, and underside of the tongue, who were presenting no external symptoms other than head-shyness. Sometimes there will be a smell evident from the mouth when the injured tissue becomes packed with feed which starts to decay. Objects can also become lodged in the palate of the mouth between the molar arcades, or between adjacent displaced teeth, which the horse cannot remove themselves. If you notice any strange symptoms in your horse such as salivating, chewing to one side, sensitivity on the face, odour from the mouth, trouble eating, resistance to the bit or a change in temperament, make sure to call your dentist even if your horse is up to date with his dental exams, as your horse may have sustained some trauma to his mouth which needs immediate treatment.