Feline Oral Resorptive Lesions

Feline tooth resorption is a common and painful condition in domestic cats. The teeth become functionally destroyed as sections of tooth are resorbed leaving areas of exposed tooth tissue below the enamel and weakened roots. These lesions were originally called feline “neck lesions” or cat “cavities” because the tooth damage was typically observed in the “neck” region of the tooth where the tooth meets the gum line. Neck lesions can appear as areas of reddened tissue at the tooth-gum interface almost as if the gingival (gum) tissue is growing into the tooth or is covering over the base of the tooth as shown in photo 1 below. In some cases, there appears to be a “hole” or concavity in the tooth (shown in radiograph [x-ray] image below). In fact many of these lesions are not clinically apparent until dental radiographs are taken and this is a key reason that Pet Care Veterinary Hospital includes dental radiographs with all dental cleanings.

The exact cause of tooth resorption has not been definitively established, but we do know that the bacteria found in the oral cavity will make these lesions worse. Therefore maintenance of good oral hygiene will help discourage progression. It has been reported that 60% of cats over 6 years of age have at least one of these resorptive lesions and once diagnosed will very likely develop additional lesions in the future. For this reason, annual dental exams, cleanings and radiographs are essential to monitor these cats to allow for early diagnosis and treatment.

Since bacteria in the mouth worsen the inflammation and pain associated with resorptive neck lesions it is ideal to manage oral hygiene through brushing your cat’s teeth daily or three times weekly at a minimum. This is your opportunity to observe your cat’s oral health. Watch for the gum tissue growing onto or into tooth resorption defects. Also observe for excess salivation, gums that bleed easily when brushed, gingival inflammation and reluctance to chew hard foods. If brushing is not possible see our section on other products that can be used in the maintenance of oral health.

     The mouth of this 12 year old cat shows what are known as dental resorptive lesions or cervical neck lesions. This occurs when the hard tissues of the root surface are destroyed by dental “clean up cells”. The destruction eventually spreads to the tooth enamel along the gum line and the enamel here is either resorbed or chips off creating these painful exposed cavities (arrows).

    This dental x-ray demonstrates the appearance of these feline resorptive lesions when Pet Care takes dental x-rays or radiographs. Note the obvious cavitated lesions (arrows).

     The cause of these feline resorptive neck lesions is unknown but incidence does increase with age. Recently, excessive dietary Vitamin D has been blamed, but this has not been definitively proven as the cause. The only treatment is to extract the painful tooth. Here Dr. Fox uses our high speed dental drill to remove bone around the tooth roots in order to make extraction easier.

     Here Dr Fox is suturing closed the tooth socket post extraction. Within a week affected cats are feeling much better; appetites and attitudes both improve!