What are FORLs?

Feline oral resorptive lesions (FORL’s) are the most common reason for a cat to need dental extractions. The holes start in the roots of the teeth causing the moth-eaten appearance we see in these x-rays and then move up toward the crown. The hole can then become big enough that the tooth becomes weakened and the crown of the tooth can then fracture off, leaving the root behind. These lesions also cause pain by eroding into the nerve cavity of the tooth, leaving exposed nerves. Most of the time though the cat will show very little signs of dental pain and carry on normally.

We still don’t know what causes these holes. What we do know is that the cells of the jaw bone start breaking down the tooth trying to turn it into bone but we don’t know what makes this process happen in some cats. This is why it is important for cats to get their mouths checked regularly and that we do full dental x-rays when performing a dental to ensure we keep the cat as healthy and pain-free as possible.

Dr Nikki Frost BSc BVSc MANZCVS (Medicine of Cats)