11/01/2022
Dog Bite Conformation: Occlusions and Malocclusions
📌 e-Ruffian.com 👀
Poor oral conformation in canines is more than a question of looks—it can affect their health.
When it comes to showing dogs, an incorrect bite can put a "dent" in the puppy's career, but not only there. Indeed, improper teeth alignment can also affect the dog's overall health and well-being. Therefore, a dog's bite is quite important, so when breed standards label improper bites as serious faults for several breeds, it's not just because of cosmetic appeal.
An improper bite is a health issue, and in working dogs, it can also interfere with their primary purposes. For instance, imagine the effect an improper bite may have on dogs bred to retrieve downed birds. But that's not all; according to Dr Karen Gellman, DVM, PhD and Dr Judith M. Shoemaker, DVM, in an article for the Canine Health Foundation, malformed dentition and distorted skull shapes may have adverse effects on posture and balance.
Let's take a better look at the dog's mouth and the impact a good or not-so-good bite may have on the dog.
Occlusion vs. Malocclusion
When a dog's mouth is inspected, judges often look at how the upper and lower incisors meet when the mouth is closed. This is known as the dog's "bite" or, more precisely, a dog's "occlusion." When the dog has a good bite, it's called a "good bite" or a "good occlusion", but when the bite is incorrect for the breed standard, it's called an improper bite or, more technically, a "malocclusion."
A good breeder should not breed dogs with an improper bite, as bite-related issues will pop up further down the line.
Scissor Bites and Level Bites
The following are ideal, or at least mostly accepted, types of bites in most breed standards. However, in certain dog breeds, some imperfections are considered the standard. We will see more about these in the malocclusion section.
Scissor Bite
In a scissor bite, the upper incisors neatly overlap the lower incisors. The upper and lower canines fit closely, the lower canines intersecting the upper lateral incisor and upper canines. In contrast, the molars intersect in a saw-tooth manner.
This is the ideal bite many dog-breed standards ask for, especially those with medium to long muzzles. The advantage of this bite is that it's effective for grasping, holding and eating food, minimizing the effect of wear and tear. According to Veterinary Medicine, any deviation from this type of bite is considered malocclusion.
Level Bite
The upper and lower incisors meet edge-to-edge in this type of bite. This bite may be accepted by some standards but often isn't considered ideal because this type of bite tends to wear down the surface of the teeth and may contribute to periodontal disease and early tooth loss.
Some breed standards call for scissors but may accept a level bite. For instance, according to the American Kennel Club, a level bite is acceptable—but not desirable—in the Labrador and undesirable in the Golden Retriever. In contrast, in the Rottweiler, it's considered a serious fault.
Overshot, Undershot and Wry Mouth
These bites may be considered faults in many breed standards, yet in some breeds, they may be the actual standard. These bites may affect how the dog grasps, holds and eats food. In severe cases, injuries to the soft tissues in the dog's mouth may occur.
Some malocclusions are caused by retained baby teeth, which push the permanent teeth out of alignment. Puppies need to be examined by the vet for around 2 to 4 months to ensure their bite is growing correctly.
Overshot
Also known as an overbite, parrot mouth, Class 2, overjet, or mandibular brachygnathism, these terms depict the same type of malocclusion. Most overbites are categorized as malocclusion and major genetic fault. The dog's upper jaw extends beyond the lower jaw in a parrot-like fashion. Because of this improper fit, the molars do not intersect in a saw-tooth manner and therefore don't align snugly as they're supposed to. Also, the dog may have difficulty grasping food, chewing and mouth injuries may result because the lower teeth hit the roof of the mouth. If there is considerable pain, some dogs may be reluctant to eat. You see this often in dogs with long muzzles, such as Russian Wolfhounds, Shelties, and Dachshunds.
Do you have a show ring candidate with an overshot bite? Well, luck isn't much in your favor, as this bite doesn't correct itself. And don't be tempted to resort to extractions or restorative treatments, as judges won't budge. Indeed, the American Kennel Club prohibits dogs who have received interventional orthodontic treatments since overshot bites tend to have a genetic basis.
Undershot Bites
Also known as prognathism and Class 3, this is the opposite of overshot bites. The lower jaw protrudes beyond the upper jaw. It's the normal bite standard for several brachycephalic breeds like bulldogs and pugs. The undershot bite may be hereditary in certain breeds. In severe overshot bites, there is a chance that the upper incisors cause pain and trauma to the lower jaw tissues. Any time the teeth don't align correctly, there are higher risks for dental disease.
Wry Mouth
This is by far the worst bite found in dogs. One side of the jaw grows faster than the other, ultimately causing the dog's mouth to twist. Affected dogs have a tough time grasping and chewing. This malocclusion is sometimes temporary, as one side of the mouth goes through a growth spurt, and the other later catches up.
An Overshot Jaw Is Normal in Puppies
Both kittens and puppies are naturally born with a slightly overshot jaw, so they can effectively nurse. Afterwards, a growth spurt will adjust the alignment once weaning and eating solid foods. According to Merck Veterinary Manual, problems start when this growth spurt doesn't occur, allowing the milk teeth to erupt, with the upper canines protruding over the lower ones.
Consider that in the German Shepherd breed, the overshot bite may spontaneously adjust until the puppy is 10 months old as long as the gap between the upper and lower incisors isn't more than the head of a wooden match, according to WebMD.
What Causes a Malocclusion?
For a good part, malocclusions are due to genetics. Selective breeding for certain facial features has contributed to a predisposition for malocclusion. Selectively breeding for longer faces and noses inadvertently predisposes dogs to develop mandibular distocclusion (i.e., an overbite), whereas selectively breeding for a shorter look predisposes to mandibular mesioclusion (i.e., underbite). However, in some cases, malocclusions can be acquired.
One example of acquired malocclusion is derived from tug-of-war games, where towels and ropes are misused, according to Dental Vet. This especially applies to puppies whose teeth are growing and a vigorous tug of war is played side-to-side.
Other causes of acquired malocclusions are retained baby teeth in puppies, especially in toy dogs, and uneven jaw growth. In some cases, baby teeth may interlock, resulting in uneven development of the jaw. Fortunately, extraction of the interlocking teeth may allow the dog's mouth to grow to its genetic potential.
It's important to have a puppy's mouth evaluated at 2 to 4 months to ensure that the mouth develops normally. Usually, by 10 months, a dog's jaws have finished growing.
Dogs with a slightly less-than-ideal occlusion should always be bred with a mate with a far superior occlusion. Still, any dog with a malocclusion should be removed from the breeding pool since, as mentioned, malocclusions are, for a good part, hereditary. The only exception is those breeds for which malocclusion is a normal and accepted breed trait.
🇺🇸 ™️
🪢WhatsApp⤵️
🌐 https://chat.whatsapp.com/LECLiiP7RqRHuvs5ZJQpbi
👀 www.youtube.com/
