Some dogs have a smile that’s impossible to forget. Their lower teeth peek out, giving them a funny, expressive face that many owners love.
An underbite is common in several breeds and is often a normal physical trait rather than a health problem.
Many dogs with underbites live healthy, active lives, although some may need extra dental care if the bite affects chewing or tooth alignment.
In this guide, I’ll introduce popular breeds known for underbites, explain why this jaw shape develops, discuss when it is considered normal, and share simple care tips to help keep your dog’s mouth healthy and comfortable.
What Are Dogs with Underbites?
Not every dog has teeth that meet evenly when the mouth is closed. Dogs with underbites have a lower jaw that extends slightly beyond the upper jaw, causing the bottom front teeth to sit in front of the top front teeth.
This jaw shape, also called a Class III malocclusion, is common in several breeds, especially those with short, flat faces.
For many breeds, an underbite is a normal inherited trait and is recognized in breed standards. It usually does not affect a dog’s quality of life if the teeth are well aligned.
In other breeds, underbites may result from jaw growth, injury, or retained baby teeth, sometimes causing chewing or dental problems.
If you’re curious about dogs with this distinctive smile or trying to identify a breed, knowing which breeds naturally have underbites is a good place to start.
Dog Breeds Known for Their Underbites
Several breeds are known for their noticeable underbites. In many of these dogs, the lower jaw is part of their natural breed look.
1. Bulldog
The Bulldog is one of the most recognizable dogs with an underbite. Its broad head, short muzzle, and forward lower jaw are part of the breed standard, giving it a distinctive appearance.
For most Bulldogs, this jaw shape is completely normal and does not interfere with everyday life.
They are calm, affectionate companions who enjoy relaxing with their families.
Crowded teeth can collect plaque more easily, so regular brushing and routine dental checkups help keep their teeth and gums healthy.
2. French Bulldog
French Bulldogs often have a small underbite due to their short faces and compact jaws. The lower teeth may peek out slightly, adding to the breed’s playful and expressive look.
A mild underbite is common and usually does not affect eating, chewing, or playing.
French Bulldogs are friendly, adaptable dogs that fit well into many households.
Since their mouths are compact, regular brushing and veterinary dental exams help reduce plaque buildup and support long-term oral health.
3. Boxer
Boxers naturally have a lower jaw that extends slightly beyond the upper jaw, making a moderate underbite part of the breed standard.
Their square muzzle gives them a strong, confident appearance that many owners admire. ‘
Most Boxers eat, chew, and carry toys without difficulty despite their bite. They are energetic, loyal companions who enjoy active families and regular exercise.
Routine dental checkups help identify uneven tooth wear or gum irritation before these problems become more serious.
4. Pug
Pugs commonly have underbites due to their short muzzles and flat faces.
Some have only a slight difference in the jaw, while others show more of their lower teeth when the mouth is closed.
This feature is considered normal for many Pugs and adds to their charming expression. They are affectionate companion dogs that enjoy spending time with their owners every day.
Routine brushing and dental care help prevent plaque buildup in their crowded mouths over time.
5. Boston Terrier
Boston Terriers may have a slight underbite that suits their short, square-shaped face.
Some dogs show their lower teeth more than others, but a mild underbite usually does not affect daily activities.
Boston Terriers are intelligent, friendly dogs known for their alert expressions and playful personalities.
They enjoy family life and are easy to train. Since their mouths are compact, plaque can build up more easily, making regular dental care an important part of their routine.
6. Shih Tzu
Shih Tzus often have a mild underbite because of their short muzzle and jaw structure.
This feature is common in the breed and contributes to their sweet, expressive face. Most Shih Tzus eat comfortably and experience no bite-related problems.
They are affectionate lap dogs that enjoy spending time with their families and adapt well to indoor living.
Regular grooming also gives owners a chance to check the mouth for tartar, inflamed gums, or other dental concerns.
7. Neapolitan Mastiff
The Neapolitan Mastiff often has a naturally undershot jaw that contributes to its bold appearance.
Its massive head and loose facial skin make the underbite especially noticeable. For many dogs, this bite is a normal breed characteristic and does not affect everyday activities.
Neapolitan Mastiffs are calm, protective companions that form strong bonds with their families.
Routine dental exams help monitor tooth wear, support healthy gums, and keep the mouth in good condition as they age.
8. Brussels Griffon
The Brussels Griffon is a small toy breed that frequently has a noticeable underbite.
Combined with its large eyes and short muzzle, the bite gives the breed its well-known expressive face.
A slight underbite is expected and usually causes no problems with eating or chewing. Brussels Griffons are curious, affectionate dogs that enjoy spending time with their owners and joining family activities.
Routine brushing helps prevent plaque from building up in their compact mouths over time.
9. Pekingese
The Pekingese often has a broad lower jaw that creates a natural underbite. Its flat face and long coat make this feature easy to recognize.
A mild underbite has been part of the breed for many years and is generally considered normal.
Pekingese are calm, independent companions who enjoy a relaxed lifestyle with their families.
Their small mouths can trap food between the teeth, making daily brushing and regular dental exams especially helpful for good oral health.
10. Lhasa Apso
Many Lhasa Apsos develop a mild underbite due to their compact jaws and short muzzles.
In most dogs, this does not interfere with eating or playing. Lhasa Apsos are alert, confident companions that stay devoted to their families and enjoy regular interaction with them.
Their long facial hair can make it harder to notice dental problems, so owners should check the mouth regularly for tartar, inflamed gums, or broken teeth during grooming sessions.
11. Tibetan Spaniel
The Tibetan Spaniel may develop a slight underbite because of its short muzzle and compact jaw.
While not every dog has one, this bite pattern appears more often than in many other toy breeds.
Tibetan Spaniels are intelligent, affectionate companions who enjoy spending time with their families and make excellent indoor pets.
A mild underbite rarely causes problems, but regular dental care and routine veterinary exams help keep the teeth properly aligned and healthy.
12. American Bulldog
Some American Bulldogs have a mild underbite, although it is usually less noticeable than in the Bulldog.
Their broad heads and muscular jaws can make the lower jaw appear slightly forward. Most American Bulldogs eat and chew without difficulty throughout their lives.
They are loyal, confident dogs that enjoy active households and regular exercise with their owners.
Routine dental examinations help confirm that the teeth meet comfortably and do not irritate the gums or lips.
13. Dogue de Bordeaux
The Dogue de Bordeaux, also known as the French Mastiff, commonly has a naturally undershot jaw.
Its large head and muscular build make this feature easy to spot. A moderate underbite is accepted in the breed and usually does not interfere with eating or normal activities.
These gentle, devoted dogs form strong bonds with their families and enjoy close companionship.
Regular dental care helps prevent plaque buildup and keeps their teeth and gums in good condition.
14. Japanese Chin
The Japanese Chin sometimes has a slight underbite because of its short muzzle and delicate jaw structure.
The lower teeth may remain visible even when the mouth is closed, adding to the breed’s unique expression.
Japanese Chins are gentle, playful companions that adapt well to apartment living and enjoy spending time with their owners.
Their small mouths can develop plaque quickly, so regular brushing and routine veterinary dental care are recommended throughout their lives.
15. Affenpinscher
The Affenpinscher often has a mild underbite that complements its short face and distinctive monkey-like expression.
This jaw shape is common within the breed and usually does not affect eating or daily activities.
Affenpinschers are lively, confident dogs with curious personalities and plenty of energy for play.
Because their mouths are compact, regular brushing and dental checkups help prevent tartar buildup while supporting healthy teeth and gums throughout their lives.
Why Do Some Dogs Have Underbites?
Dogs have underbites because of inherited breed traits, uneven jaw growth, retained baby teeth, injuries, or developmental conditions.
In many breeds, an underbite is a normal physical characteristic rather than a health problem.
Flat-faced breeds such as Bulldogs, Boxers, and Pugs commonly inherit shorter upper jaws, making the lower jaw appear more prominent.
In other dogs, the upper and lower jaws may grow at different rates during puppyhood, creating an uneven bite.
Retained baby teeth can also shift permanent teeth out of position and affect jaw alignment if not removed promptly. Less commonly, jaw injuries or congenital developmental conditions change how the jaws meet.
Treatment depends on severity. Dogs that eat comfortably without pain may only need monitoring and regular dental checkups.
Signs an Underbite May Need Veterinary Care
Many dogs with underbites live healthy, comfortable lives. Still, some bite problems can affect eating, tooth alignment, or the soft tissues inside the mouth.
- Difficulty eating: Your dog struggles to pick up food, chew normally, or frequently drops food while eating.
- Pain while chewing: Whining, avoiding hard treats, or chewing on only one side may indicate discomfort.
- Bleeding or swollen gums: Teeth rubbing against the gums or roof of the mouth can cause irritation and small injuries.
- Bad breath: Persistent bad breath may be a sign of plaque buildup, gum disease, or food trapped between crowded teeth.
- Loose or broken teeth: Teeth that do not meet properly may wear down faster or become damaged over time.
- Excessive drooling: More saliva than usual can occur if the underbite irritates the lips or makes closing the mouth difficult.
- Weight loss or poor appetite: Dogs that find eating uncomfortable may begin eating less, which can lead to gradual weight loss.
How to Tell if an Underbite Is Normal?
A mild underbite is expected in several dog breeds and often causes no problems. In other cases, it may affect eating, comfort, or dental health.
| A Normal Breed Underbite | An Underbite That Needs Attention |
|---|---|
| Common in breeds such as Bulldogs, Pugs, Boxers, and Shih Tzus | Appears in a breed where underbites are uncommon |
| The dog eats, drinks, and chews without difficulty | Trouble chewing, dropping food, or eating slowly |
| Teeth do not injure the lips, gums, or roof of the mouth | Teeth press into the gums or the roof of the mouth |
| No signs of pain or discomfort | Bleeding, swelling, or pain around the mouth |
| Bite remains stable as the dog grows | Bite becomes more noticeable or changes over time |
| Regular dental exams show healthy teeth and gums | Broken, worn, crowded, or loose teeth are present |
How Are Underbites Treated in Dogs?
Many dogs with mild underbites never need treatment. If the bite does not cause pain or interfere with eating, your veterinarian may simply recommend regular monitoring during routine checkups.
- Regular dental care: Professional cleanings and routine oral exams help reduce plaque buildup and identify dental problems before they become more serious.
- Baby tooth removal: Retained baby teeth may be removed if they block adult teeth from growing into the correct position or contribute to bite problems.
- Tooth extraction: Teeth that are damaged, overcrowded, or causing injuries inside the mouth may need to be removed to relieve pain and prevent further complications.
- Orthodontic treatment: In selected cases, a veterinary dental specialist may use orthodontic techniques to improve tooth alignment and make chewing more comfortable.
- Jaw surgery: Surgery is uncommon and is usually reserved for severe underbites that affect eating, cause repeated mouth injuries, or reduce a dog’s quality of life.
Are Underbites Linked to Breathing Problems?
Yes, underbites can be linked to breathing problems in some dogs, but not every dog with an underbite has difficulty breathing.
The risk is highest when the underbite is part of a flat-faced skull shape rather than the bite itself.
An underbite alone does not automatically affect breathing. However, many brachycephalic breeds, such as Bulldogs, Pugs, and Boxers, naturally have underbites, shortened noses, and narrowed airways.
These features can contribute to breathing issues, snoring, noisy breathing, exercise intolerance, and overheating.
In dogs with severe jaw abnormalities, the bite may also make it harder to keep the mouth closed comfortably. If your dog has breathing trouble, blue gums, or collapses after exercise, see a veterinarian as soon as possible.
How to Care for Dogs with Underbites?
Most dogs with underbites need only routine care to keep their mouths healthy. Paying attention to their teeth and eating habits can help prevent small problems from becoming larger ones.
- Brush the teeth regularly: Use a dog-safe toothbrush and toothpaste to reduce plaque and keep the gums healthy.
- Schedule routine dental exams: Regular veterinary checkups can identify worn teeth, gum disease, or bite-related problems early.
- Offer appropriate chew toys: Choose durable toys that clean the teeth without being so hard that they increase the risk of tooth fractures.
- Watch eating habits: Notice whether your dog has trouble chewing, drops food, or seems uncomfortable during meals.
- Check the mouth often: Look for bleeding gums, bad breath, broken teeth, or sores where the teeth touch the lips or roof of the mouth.
- Feed a balanced diet: Good nutrition supports healthy teeth and gums while helping maintain your dog’s overall health.
Myths and Facts About Dogs with Underbites
Dogs with underbites are often misunderstood. While some bite problems need treatment, many underbites are simply part of a dog’s natural breed characteristics.
| Myth | Fact |
|---|---|
| All dogs with underbites have health problems. | Many breeds naturally have underbites and live healthy, comfortable lives. |
| Every underbite needs treatment. | Mild underbites often require only regular dental checkups and good oral care. |
| Dogs with underbites cannot eat normally. | Most dogs with mild underbites eat, drink, and chew without difficulty. |
| Underbites only occur in Bulldogs. | Several breeds, including Boxers, Pugs, Shih Tzus, and Brussels Griffons, commonly have underbites. |
| An underbite always gets worse with age. | Many underbites remain stable throughout adulthood, especially when they are inherited breed traits. |
| Dogs with underbites should not be adopted. | An underbite alone does not affect a dog’s ability to be a loving, active companion. |
Conclusion
Dogs with underbites come in many shapes and sizes, from Bulldogs and Boxers to Shih Tzus and Brussels Griffons.
For many of these breeds, an underbite is a normal physical trait that does not affect their daily life.
The key is knowing when it is simply part of a breed’s appearance and when it may be linked to dental or jaw problems.
Regular veterinary checkups and good oral care can help keep your dog’s mouth healthy for years to come.
If you notice changes in your dog’s bite or eating habits, speak with your veterinarian. For more breed guides and dog care tips, keep reading our pet resources.
Frequently Asked Questions
Which Dog Breeds Naturally Have Underbites?
Bulldogs, French Bulldogs, Boxers, Pugs, Shih Tzus, Boston Terriers, and several other flat-faced breeds commonly have natural underbites.
Can a Dog Live a Normal Life with an Underbite?
Yes. Most dogs with mild underbites live healthy, active lives if the bite does not interfere with eating, chewing, or oral health.
Do Dogs with Underbites Need Braces?
Usually not. Most underbites are managed through routine dental care or, when necessary, tooth extractions. Braces are used only in selected medical cases.
Can a Puppy Outgrow an Underbite?
No. An underbite generally does not correct itself as a puppy grows and may become more noticeable with age.
Are Underbites Painful for Dogs?
Not always. Many underbites cause no discomfort, but severe cases can lead to mouth injuries, uneven tooth wear, chewing problems, or gum irritation.