Brachycephalic dental issues:French bulldogs, pugs, Persian cats

How a shortened skull affects the teeth

Brachycephaly is a shortened, “flat” face fixed by selective breeding. In dogs this includes French and English bulldogs, pugs, Boston terriers, Shih Tzus and Pekingese; in cats — Persians, Exotic Shorthairs and Himalayans. The facial part of the skull is shorter, especially the upper jaw, but there are no fewer teeth: an adult dog has 42 and an adult cat has 30.

The teeth simply run out of room, and this is visible even at a routine examination:

• crowding — teeth stand tightly against each other, without the usual gaps;
• rotation — a premolar is turned sideways or almost across the dental arch;
• overlapping — one tooth partly sits behind another;
• displaced teeth — a tooth has erupted on the inside or outside of the arch, or at an angle;
• unerupted or missing teeth — for some teeth there was no room at all.

Every such contact point is a plaque trap. Toothbrush bristles, the tongue and the cheeks cannot reach it, and food gets stuck between the teeth. That is why gum inflammation in brachycephalic pets often starts in the crowded areas: the next tooth may be healthy while a periodontal pocket is already forming between two rotated premolars.

Persian and Exotic cats

In cats with a very short face, the teeth can also be crowded or angled, and the lower jaw can stick out in front. At the same time, gingivitis, periodontal disease and tooth resorption (TR) affect cats of any breed, so at the examination I assess not only “breed” features but the whole mouth.

If a Persian cat starts eating differently — biting into food more carefully, dropping it or eating on one side — do not put it down to the shape of the face: this can be a sign of dental pain.

Underbite in bulldogs and pugs: when it is a breed trait

Most dogs and cats have a “scissor” bite: the upper incisors slightly overlap the lower ones, and the lower canine sits in the gap between the upper third incisor and the upper canine. In brachycephalic breeds the upper jaw is shorter, so the lower jaw often sticks out and the lower incisors end up in front of the upper ones. In AVDC nomenclature this is a class 3 malocclusion (mandibular mesioclusion), commonly called an underbite. For bulldogs and pugs this bite is written into the breed standard.

But a breed standard is not a medical criterion. For me the key question is different: do the teeth touch soft tissue or each other where they should not? If not, the bite remains a breed trait and needs no treatment. If they do, this is traumatic occlusion: it hurts every day, leaves sores and pits in the gums and palate, and wears down or chips the teeth.

What is done if the teeth injure the gums or palate

Orthodontics does not change the skeletal bite of a brachycephalic pet: it works with the position of individual teeth. So the aim of treatment is not a textbook “correct” bite but a mouth free of pain and injury. I plan treatment after the examination and dental radiographs, because the roots, the state of the pulp and the pet's age determine what is possible:

• in puppies — extraction of deciduous teeth that injure the palate or keep the permanent teeth from moving into place;
• orthodontic correction — moving individual teeth, for example with an inclined plane, when this is realistic for the particular bite;
• crown reduction with vital pulpotomy — the tooth is shortened so it no longer causes injury, while the living pulp is protected with a filling and monitored on radiographs;
• extraction of the offending tooth — when other methods are not suitable.

More about these options is on the page on orthodontics and bite correction. If you see a sore or a pit on the palate, start with the page on a canine tooth hitting the palate — it explains how to check the mouth at home and what to do before the visit.

A missing tooth: unerupted teeth and dentigerous cysts

When a short jaw runs out of room, some teeth may fail to erupt and stay in the bone or under thick gum tissue. In dogs this often involves the lower first premolars (teeth 305 and 405), but canines and other teeth can also stay unerupted. Brachycephalic and small breeds are predisposed.

An unerupted tooth may cause no signs for a long time. But a dentigerous (follicular) cyst can form around its crown — a fluid-filled cavity that slowly enlarges and destroys the jaw bone and the roots of neighbouring teeth. A cyst does not form around every unerupted tooth, and there is no way to predict it from the outside. Dentigerous cysts in dogs are the subject of clinical and histopathological studies — for example, Vesterinen et al. (2024) analysed 279 such cysts in 192 dogs.

The gum over an unerupted tooth looks exactly like the gum where there is no tooth at all. So a missing tooth in a brachycephalic pet is a reason for dental radiography, even if your pet seems perfectly well: only X-rays show whether the tooth never formed, is stuck in the bone or has left a root behind. What to do if you notice a gap is covered on the page about a missing tooth.

In a cat, a gap in the dental arch also needs X-rays: the tooth may have been lost to tooth resorption (TR), broken off leaving a root in the bone, or never formed.

An unerupted tooth with a cyst is extracted together with the cyst lining, and the cyst tissue is examined histologically. The earlier the tooth is found, the less bone is lost. Sometimes monitoring with a clear plan of follow-up X-rays is chosen, and a large cyst may require a CT scan. Diagnosis and treatment options are covered in detail in the article on an unerupted tooth in a dog.

Periodontal disease in brachycephalic pets: why it starts between the teeth

Periodontal disease is driven by bacterial plaque: first the gums become inflamed, then the inflammation spreads to the ligament and bone around the root. Many brachycephalic dogs are small, and small dogs have less bone around the roots, so even a little bone loss significantly weakens a tooth.

In a crowded mouth, periodontal pockets often hide where they cannot be seen: between teeth, on the palatal side, on the rotated surface of a tooth. Bad breath and red or bleeding gums are a reason for an examination, but their absence does not mean the gums are healthy. Pocket depth and bone loss can only be assessed by probing and dental radiography under anaesthesia.

Treatment depends on the stage: cleaning above and below the gum line, treatment of periodontal pockets and, in some cases, regenerative techniques. If two teeth stand so tightly that the area cannot be kept clean and periodontal disease is already destroying bone, it is sometimes better to extract one of them to save its neighbour. I make that decision only after radiographs. Stages and symptoms are covered in the article on periodontal disease in dogs.

Anaesthesia for a French bulldog, pug or Persian: what is taken into account

Brachycephalic pets have a narrower airway: narrowed nostrils, an elongated soft palate and sometimes a narrow larynx and trachea. Together this is called brachycephalic obstructive airway syndrome (BOAS). Under anaesthesia and especially during recovery, when the muscles are relaxed and the breathing tube has already been removed, the airway can become obstructed. The risk of regurgitation — stomach contents flowing back up — is also taken into account in these patients. Short-nosed cats can have similar features, so for Persian and Exotic cats the plan is drawn up just as carefully.

That is why anaesthesia for a brachycephalic pet is planned separately, and it is given and monitored by a veterinary anaesthetist while I work in the mouth. The general approach is described on the page on anaesthesia and safety; here is what changes for short-nosed patients:

1. 01

   Before the procedure

   Examination and tests according to an individual plan. Tell us whether your pet snores, breathes with its mouth open, how it copes with heat and exercise, and whether it stops breathing in its sleep, vomits or regurgitates. If breathing problems are significant, a consultation with another specialist about the airway may be needed.

2. 02

   Induction

   Before induction the patient is usually given oxygen to breathe, and induction and intubation are carried out quickly and in a controlled way so that the airway is protected by the tube as soon as possible.

3. 03

   During the procedure

   The anaesthetist continuously monitors breathing, heart rhythm, blood oxygen saturation, blood pressure and temperature. The tube in the trachea protects the airway from water, plaque and blood.

4. 04

   Recovery

   The tube is removed later than usual — once your pet is swallowing and can hold its head up. Then it rests on its chest with the head raised, and its breathing is watched until it is stable.

5. 05

   At home

   Written instructions on feeding, medication and what to watch for. Laboured breathing or pale or bluish gums are a reason to contact the clinic straight away.

Home care when the mouth is crowded

Daily brushing is the most effective thing you can do at home, and in a crowded mouth technique matters even more:

• a small-headed brush — a soft child's brush or a veterinary brush for small breeds reaches behind rotated teeth better than a large one;
• an angle of about 45° to the gum and short strokes — this way the bristles get into the gaps between teeth and under the gum margin;
• extra attention to the premolars — this is where teeth are often crowded or rotated;
• veterinary toothpaste — human toothpaste is not suitable;
• free breathing — do not hold the mouth shut by force or press on the nose, and take breaks: short-nosed pets already find it harder to breathe through the nose;
• for Persian cats — gradual training, a few seconds at a time, with rewards; if your cat will not allow brushing, we will discuss a realistic plan.

Dental treats, gels and rinses can only supplement the brush; among them, choose products with the VOHC seal. Once a week, lift the lips and check the gums, the palate and the gaps between the teeth. Step-by-step technique is covered in the article on caring for your dog's or cat's teeth at home.

When to see a veterinary dentist and what a check-up includes

The first visit is worthwhile while the teeth are changing, from 3–4 months: this way deciduous teeth that have not fallen out, a traumatic bite and teeth that have not come through can be spotted in time. After the teeth have changed, it is worth checking that all the permanent teeth are in place. An adult pet needs regular check-ups, and I set the interval individually — based on the gums, how crowded the teeth are and how well home care is going.

If you are not in Kyiv, start with an online consultation: photos of the bite, gums and palate help judge how urgently an examination is needed. The check-up with a veterinary dentist itself has several stages:

1. 01

   Consultation

   Without anaesthesia: I count the teeth, assess the bite and tooth contacts, the gums, palate, plaque and tartar, and ask about breathing and eating. I explain what can be seen now and what needs radiographs.

2. 02

   Preparation

   Pre-anaesthetic tests according to an individual plan, with the plan agreed with the anaesthetist.

3. 03

   COHAT under anaesthesia

   Examination and probing of every tooth, full-mouth dental radiography, and cleaning of the mouth above and below the gum line.

4. 04

   Treatment and follow-up plan

   Treatment when clinically indicated, home-care recommendations and the date of the next check-up.

Frequently asked questions