Puppy Underbite: What Is It & Can It Be Corrected?

By John Martin - May 12, 2021

Cute puppy with underbite

Underbite. As long as there is no visible problem, some people think an underbite dog is cute or attractive.

But here’s the thing. It is a problem and you must do all you can to fix it. This is a common problem among many dog breeds but you must not ignore it.

Biologically, domestic dogs show more variation in terms of size, shape, hair and head shape more than any other animal. In contrast, wild canids actually look really similar.

They are medium sized, have a medium length hair coat and a cone-shaped skull. But why is anatomy important?

That’s just the first of many essential questions that you will need to answer to have or want to get a dog.

What Is an Underbite?

Technically called canine malocclusion, an underbite is a condition when the mandible teeth are in front of the maxilla teeth. In lay man’s terms, an underbite is when the lower row of your dog’s teeth protrude out ahead of the upper row.

This is commonly seen in bulldogs and pugs and is not a rare phenomenon. Underbites can sometimes be a problem, depending on the severity of the condition.

As a (potential) dog owner, you must be able to identify an underbite dog, check if it is a problem and how to correct it. Because if it is severe, your dog might even need surgery.

Identifying an Underbite Dog

Dogs are not like humans. We have a clear jaw structure and a definition of “normal” when it comes to dental health.

But these things change for dogs depending on the breed and sometimes even the litter. So, identifying an underbite dog is a bit tricky.

The identification process must start right at the beginning. As soon as you get the puppy, you must take them to a vet.

Make sure that the vet performs dental occlusion on the puppy and documents it in the medical record. The process of dental occlusion starts with identifying the skull type (brachycephalic, mesocephalic or dolichocephalic).

If there is a possibility or presence of an abnormality, you will either see indications or have the information to prepare for an underbite. After that, the vet must look at facial symmetry.

Many dogs have anisognathic jaws. This means that their upper jaw or maxilla is a lot wider than their lower jaw or mandible.

The vet must assess dental interlock. If the structure is normal, the lower jaw incisors are upon the cingulum which is a ridge of enamel on the base of a tooth’s crown.

They should also have a three-way interlock of the upper jaw third incisors, the lower jaw canines and the upper jaw canines. There’s more to the process but why not leave it to your vet?

Meanwhile, this is what you need to do. Yes, there is some work for you too. You must look at it in terms of comfort and function.

If the underbite is visual but they are able to eat comfortably, it might be fine after all. But if your dog has a tooth or tissue contact problem that is unusual, your canine is in pain or is at least experiencing discomfort.

You must rush to a vet and talk about treatment before it leads to other health issues. Bulldogs, for example, often have teeth over the top lip even when the mouth is shut.

But it should not be ignored simply because it is commonly found. You must also remember that some dogs have had a distressing underbite for so long that they might not show it and have learned to live with the pain.

Related: Puppy Acne 101

Why Does This Happen?

There are two types of canine malocclusions—skeletal and dental.

Dental malocclusions occur when the dog’s teeth are positioned abnormally. And skeletal malocclusions occur when the dog’s facial structure is abnormal.

Both result in the dog’s teeth not fitting together which is sometimes genetic. It can also be developed during gestation or early development stages. Injuries and infections in puppies are also a probable cause of malocclusions.

Malocclusions can also be the result of trauma. It results in the puppy not being able to chew properly.

Let’s see why the shape of the skull is important.

Domestic dogs have three types of skulls. Those with brachiocephalic or short-nosed skulls have underbites.

When the shape of the skull is distorted, the teeth erupt crookedly and it leads to the condition we call malocclusion. The significance of a dog’s teeth goes beyond its mouth.

A dog’s teeth and its temporomandibular joints (TMJs) give the brain critical information about posture. The dog’s nervous system checks the TM joints for weight-bearing purposes.

If the TM joints are symmetrical, the nervous system is assured that the brain is being supported by a symmetrical structure. And it is the top-most priority of the nervous system to keep the brain safe.

So, a dog with a good bite has good posture, which is typically found in functional dogs from a good breed.

In some breeds, underbites occur naturally but sometimes, it is the result of questionable breeding practices. Some pups are engineered with a certain jaw structure so that they can look more like a bulldog or a boxer.

If an underbite is left unattended, the dog is at a greater risk of multiple health issues. Because, when a dog has malocclusions, the rest of the body will have an adapted posture and give it weight-bearing issues and possibly lead to injuries too in the future.

Related: How to Get Rid of Bad Puppy Breath

Health Issues with an Underbite Dog

As long as the puppy is able to chew and eat comfortably, you don’t need to worry a great deal. But if you neglect a serious case of malocclusion, it might lead to other problems.

If the dog has misaligned teeth, it might have trouble chewing, eating and can also damage its gums and soft tissues. This leads to discomfort and an increased risk of infection, gingivitis and gum diseases.

When a severe case of malocclusion goes untreated, it can cause an oronasal fistula, which is a condition where a hole is formed between the nose and mouth of the dog. This leads to nasal disease, infection and severe pain.

You can identify this beforehand by looking out for some signs. Your canine might show signs of oral pain but moving away when you pet its face. They may experience difficulty in eating or have bad breath or blood in the saliva.

They may also rub their head against the wall or with their paws. They will have difficulty in picking up or chewing food and their trouble will be visible.

Side note—if your dog is eating slowly or having trouble chewing and swallowing because of an underbite, you must take them to the vet. Because even when the dog is eating, an underbite might lead to eating disorders.

How to Correct it

In some breeds, an underbite occurs naturally. If your dog comes from one of those breeds, it might have it forever. But if not, the misalignment of teeth might fix itself once the puppy grows up.

And as long as it is not a problem for your dog, it will learn to live with it like they do with most problems. However, if you are concerned about the health and happiness of your puppy, rest assured that underbites can be corrected.

There are three main dental procedures that are performed on pets.

First is the movement of secondary teeth. This is when active or passive force is applied on the teeth to correct their eruption angle or just the present position.

Second is modifying the crown. This is the process of shortening or modifying crowns to remove occlusions caused due to trauma.

The third procedure is called interceptive orthodontics. This is the process of selective extraction of primary teeth to guide the teeth into a better eruption position.

Which means, you remove the crooked primary teeth and monitor the eruption of secondary teeth.

In puppies with growing teeth and facial bones, extraction and filling could be the solution to your problems. You could also opt for braces just like you would with a human child.

Vets have been doing this since the 1980s when there is a medical issue. Unlike humans, braces are not used to make a puppy look better.

In adult dogs though, extraction and filling is your best bet to correct an underbite.

If a vet determines that your puppy needs braces, they must also check to see if your puppy is healthy enough for the procedure which involves taking X-rays and getting under general anesthesia (if your canine is a biter). The latter can be avoided if it is a well-behaved puppy.

You must also avoid giving them chew toys because it is known to make underbite worse. This is also applicable to puppies with braces.

Once they get the braces, you must keep the chew toys away for a while and avoid giving them food that is hard to swallow. And don’t forget to brush their teeth regularly.

Breeds with Underbites

Shih Tzus, Pugs, Lhasa Apsos, King Charles Spaniels, English Bulldogs, French Bulldogs, Boston Terriers and Pekingese dogs are most likely to develop underbites. In such cases, you don’t always have to approach it medically.

In some of these breeds, however, underbites are more severe than others. Hence, if you see your dog in distress take them to a vet.

But remember that dogs belonging to any breed can develop an underbite. For example, small dogs are most known to develop underbites easily but large dog breeds like boxers are also at risk of developing one.

If you have a mixed breed dog, they will be at risk of developing an underbite even if one of their parents is from the above-mentioned list of dogs.

Parting Thoughts

An underbite is a common occurrence in many dogs. When the dog comes for a certain breed it is natural and it does not need medical attention if the dog isn’t in pain.

It is a problem when the dog is in pain and yes, it can be fixed. An underbite can be fixed through braces or surgery.

If it is left untreated, in a mild form it can lead to eating disorders. If it is severe it can lead to other major health issues.