Dental treatment: FORL

  • Cat

FORL stands for feline odontoclastic resorptive lesions and is a degenerative disease of teeth in cats. This disease is now often referred to simply as RL (resorptive lesions). FORL is one of the commonest and most painful diseases in cats. Nearly one in three cats suffers from FORL, and even one in two cats over the age of 5 years, and all breeds are affected. Persian and Siamese cats appear to be affected particularly often.

FORL is a dental disease of cats in which the tooth and its roots dissolve. FORL is thought to be due to a disorder of calcium metabolism. It is assumed that calcium deficiency leads to mobilisation of calcium components from the cat’s teeth. Because of the calcium deficiency cells are activated that then develop into what are known as odontoclasts. Odontoclasts break down dentine by withdrawing the calcium deposited in it. Dentine is the main bone-like component of the tooth right down to its roots. Destruction of dentine means destruction of the complete periodontium, the structure that surrounds and supports the tooth, which means the end of the affected tooth. The odontoclasts that break down the dentine originate as endogenous cells so FORL can be classified as an autoimmune disease. Although the dentine is dissolved, the nerves of the tooth remain intact, so affected cats have severe pain. There is evidence that a reduced calcium supply in the cat’s diet can also be involved in the disease. You can ask your vet to recommend a cat food that will provide your cat with sufficient calcium.

Three forms of FORL in cats are distinguished: type 1 FORL usually develops together with plaque, tartar and inflammation of the periodontium (periodontitis) and gum (stomatitis).Type 2 FORL usually develops initially without involving inflammatory processes. Breakdown of the tooth progresses under the gum and cannot be identified visually at first. Type 3 FORL is a combination of type 1 FORL and type 2 FORL. Both inflammatory and non-inflammatory processes occur.

What symptoms suggest FORL in my cat?

In the initial stage FORL cannot be recognised with the naked eye. FORL shows symptoms in the cat only when there is advanced decay. When the dentine in the root has dissolved, the nerve in the tooth comes in contact with the mouth’s flora and all the bacteria it contains, and the extreme pain starts. To recognise the symptoms of FORL in one’s cat, one needs to recognise the signs of toothache.

If FORL is suspected, watch your cat for:

  • A change in behaviour when feeding, such as refusal of dry food or cries of pain when eating
  • Increased drooling
  • Grinding or chattering the teeth
  • Shaking the head or tilting the head

As the disease progresses, it can be observed in the mouth that teeth appear to be missing though they sometimes have only broken off at the neck of the tooth. In addition, inflamed gums and redness as well as proliferation of the gum occur (especially in type 1 FORL).

If you suspect that your cat could be suffering from FORL, you should bring your cat promptly to a vet. You can also find out beforehand which veterinary practice or hospital in your vicinity has a vet with training in dentistry for cats as well as the appropriate equipment such as digital dental X-ray. The vet will examine the cat and probe the oral cavity if anything is suspected. This means that he will palpate the teeth and gums with a pointed probe. Chattering of the cat’s teeth, a typical sign indicating pain, can be evidence of FORL. Taking X-rays is absolutely essential for the diagnosis of FORL as only this can show if dentine has already dissolved under the gum. About six X-rays are needed for complete assessment of tooth status and these are taken under a brief anaesthetic. Ask your vet to X-ray the jaw every time the teeth are cleaned so that disintegration of the tooth roots can be identified as early as possible. Since professional and humane tooth cleaning can only be performed under anaesthetic, it is possible to take the X-ray at the same time.

How is FORL treated?

Decay of tooth substance can be neither prevented nor reversed by FORL treatment. For this reason, all teeth attacked by FORL must be removed completely. The vet must do this under general anaesthetic and X-ray control in order to be sure that all affected teeth have been completely extracted. Remnants of the tooth roots remaining in the jaw can lead to a new focus of inflammation. The gaps produced by the extraction are then sutured closed to prevent food particles from getting into them. The cat will be able to feed again the day after the operation. Your cat will manage well even without a full set of teeth. Switching from dry to wet cat food may make it easier for them to eat. The sutures do not have to be removed as a suture material is used that dissolves as the wound heals. The cat is given an antibiotic to combat the inflammation caused by FORL. In some cases, it is advisable to start giving the antibiotic before the dental operation so as to reduce the risk of bacterial infection. You can trust your veterinary surgeon to calculate the dosage of the antibiotic according to the risk and benefit and to prescribe only as much antibiotic as is absolutely necessary to enable your pet to heal. The cat is given a painkiller throughout the entire treatment.

Many animal owners would like homeopathy for cats with FORL as an alternative to dental extraction. Orthodox veterinary surgeons and homeopaths are in agreement that there is no drug against FORL. Unfortunately, the diseased teeth have to be removed. It is possible, however, to give homeopathic remedies that are thought to improve the cat’s immune system and comfort.

What costs must I anticipate for treating my cat’s FORL?

Only your vet can estimate the cost of treating the cat’s FORL as the costs incurred for the diagnosis and treatment are determined greatly by the progress of the disease. The more teeth are affected, the more teeth have to be removed.

FORL in cats is a common autoimmune disease in which the cat’s teeth dissolve from within outwards, causing great pain. The development of FORL can be neither predicted nor prevented. On average, however, every second cat is affected in the course of its life. If you want to minimise the risk for your cat, you should attend your vet regularly for a health check with an X-ray of the teeth. In this way, the disease can be diagnosed as early as possible and the animal can be helped rapidly.

© AniCura

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