Lip Entrapment

Lip entrapment is a condition that we see most frequently in feline patients. Most cases of lip entrapment occur following the extraction of a maxillary canine tooth.  

Cats have relatively tight upper lips compared to our canine patients. The presence of the maxillary canine tooth aids in holding the lip out to a sufficient degree that when the mouth closes the mandibular canine tooth slips inside the upper lip without causing trauma. Loss of the maxillary canine tooth can allow the upper lip to drop inwards. For some cats this results in the lower canine contacting, trapping and traumatising the upper lip.  

This may be noted intermittently and cause minimal to no concern. Other patients experience more significant trauma with hair loss to the upper lip, thickening of the lip and even chronic ulceration and eosinophilic granuloma formation. In patients with this more significant trauma treatment of the mandibular canine tooth is necessary.  

When treatment is required there are two approaches: 

1. Reduction of the height of the mandibular canine tooth and subsequent endodontic therapy with either root canal therapy or vital pulpotomy. 
2. Extraction of the mandibular canine tooth  

Both treatment options will alleviate the trauma to the upper lip, the treatment that is right for each patient and pet owner will vary and is best discussed after an examination as many factors are considered in the decision-making process. 

Ideally, we would prevent this trauma by saving the maxillary canine tooth when possible. This is not always the case due to conditions such as advanced periodontal disease and tooth resorption and some patients will go on to experience this complication. 

It can be challenging to predict the patients that will suffer lip entrapment following extraction of the maxillary canine teeth. If your pet is one of the minority of patients experiencing this complications treatment can be provided to improve their comfort and quality of life.