Malocclusions in Dogs

A malocclusion is an abnormal teeth alignment. They can become a problem in dogs, just as they can become a problem in humans. Today, our Bellevue vets discuss malocclusions on dogs, the different types, and what you can do to help.

What is malocclusion in dogs?

An adult dog has 42 permanent teeth divided into four different types:

1. Incisors are the teeth located between the upper and lower jaws. They are used for grasping food and they help keep the tongue in the mouth.
2. Canine teeth are located on the sides of the incisors and are used to grasp food and other objects. The lower canines help keep the tongue in the mouth.
3. Premolars are located behind the canines in both the upper and lower jaws and shear or cut food.
4. Molars are behind the premolars at the back of the mouth. They are used for grinding food to prepare it for swallowing.

Malocclusions in dogs can lead to difficulty eating, tooth decay, and even pain. Additionally, severe malocclusions may require surgical correction to prevent further issues.

What are the different types of malocclusion in dogs?

Canine malocclusion is classified into two types: skeletal and dental. Dental malocclusion occurs when the upper and lower jaw lengths are normal, but one or more teeth are misaligned. Skeletal malocclusion occurs when an abnormal jaw length causes misalignment of the teeth.

Common Types of Skeletal Malocclusion

Mandibular Distoclusion or Class 2 Malocclusion (MAL2): Also known as an overjet, overshot, mandibular brachygnathism, or overbite in dogs. This occurs when the lower jaw is shorter than the upper jaw. When the mouth is closed, the lower jaw teeth do not occlude with their upper jaw counterparts. When compared to their counterparts in the lower jaws, the upper premolars are too far away from the nose.

Mandibular Mesioclusion or Class 3 Malocclusion (MAL3): Also known as an underbite, undershot, mandibular prognathism, or reverse scissor bite in dogs. This is a condition in which the lower jaw is too long in relation to the upper jaw and the lower teeth protrude in front of the corresponding upper teeth. If the jaw length difference is small, the upper and lower incisor teeth may meet edge to edge, resulting in an even or level bite.

Maxillomandibular Asymmetry: Upper and lower jaw asymmetry can manifest itself in a variety of ways, including rostrocaudal asymmetry (upper and/or lower), side-to-side asymmetry (upper and/or lower), and open bite (one or both sides). Side-to-side asymmetry is caused by a lack of centering of the upper and lower jaws over each other, whereas rostrocaudal asymmetry is caused by a length disparity between the right and left sides. An abnormal (increased) space between the upper and lower jaws causes an open bite.

Common Types of Dental Malocclusion

Rostral & Caudal Crossbites: Rosrtal crossbite occurs when the canine and premolar teeth on both sides of the mouth are aligned but one or more lower incisors are in front of the upper incisors when the mouth is closed. Caudal crossbite occurs when one or more lower cheek teeth are closer to the cheek than the opposing upper cheek teeth when the mouth is closed.

Linguoverted Mandibular Canines: This malocclusion is a condition in which the lower canine tooth is angled inward, resulting in traumatic contact between the linguoverted canine and the roof of the mouth. It can be treated using a variety of methods, including tooth movement, crown reduction, restoration, or extraction.

Mesioverted Maxillary Canines: This dental malocclusion can be inherited (as in Shelties) or acquired as a result of persistent deciduous teeth.

Is there treatment for malocclusion in dogs? 

There may be no need for treatment for dogs who have misaligned teeth but can bite, chew, and swallow normally. Outside of neutering or spaying the animal to prevent future puppies from having the same problem, there isn't much that can be done to "correct" the dog's teeth or jaw alignment due to genetics.

However, for dogs in pain, the first option is to extract deciduous teeth, which have been linked to oral discomfort and disease in dogs over the age of ten months. To avoid long-term problems, veterinarians recommend that pet owners pay close attention to their dog's tooth pattern during the puppy stage.

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.