PetLabCo Logo
  1. Home/
  2. Dog/
  3. Health & Wellness/
  4. 9 Signs of Rotten Dog Teeth You Shouldn’t Ignore

9 Signs of Rotten Dog Teeth You Shouldn’t Ignore

This article outlines the key signs of rotten teeth in dogs that pet owners should watch out for.

12 min read·Updated: Nov 11, 2025
9 Signs of Rotten Dog Teeth You Shouldn’t Ignore

Quick takeaway: Rotten teeth in dogs can be caused by poor dental hygiene, a high sugar diet, breed predispositions, underlying health issues or genetics. If you think your dog has rotten teeth, it is important to book a dental cleaning with your veterinarian, as rotten teeth can cause significant pain and discomfort for dogs.

Rotting Teeth in Dogs

If you are concerned about your dog’s teeth rotting, or you think your dog might have an infected rotten tooth, it’s important to know what causes rotting teeth in dogs, and what you can do to support your dog’s oral health and hygiene at home.

Dog tooth decay, commonly known as cavities or caries, is relatively rare, affecting about 5 percent of dogs. However, periodontal disease, which involves inflammation and infection of the tissues surrounding a dog’s teeth, affects up to 80% of dogs over the age of two.

The rarity of cavities in dogs can be attributed to the shape and structure of their teeth. Except for the molars located at the back of their mouth, dog teeth are shaped like pointy cones. This conical shape helps keep the teeth spaced apart, reducing the likelihood of food getting stuck between them, helping to prevent cavities. Additionally, a dog’s saliva is slightly higher in pH, which helps neutralize acids in the mouth and further protect against tooth decay.

What Causes Rotten Dog Teeth?

Rotten teeth in dogs, also known as dental disease or periodontal disease, can be caused by several factors:

Poor Dental Hygiene Can Lead To Infected or Rotten Dog Teeth

One of the most common causes of tooth decay in dogs is a lack of regular teeth brushing and dental care. When plaque, a soft film of bacteria, is not removed through brushing, it hardens into tartar. This tartar build-up can lead to decay and gum disease.

A High-Sugar Diet Can Lead To Dogs’ Teeth Rotting

Just like us, feeding a diet high in sugar or simple carbohydrates can contribute to the formation of plaque and tartar. Wet foods, which can stick to teeth more than dry kibble, may also exacerbate the problem if dental hygiene is not maintained. However, if your dog is on a dry food diet, it can help scrape away dirt from teeth while your dog chews. 

Some Dog Breeds Are More Predisposed To Tooth Decay and Teeth Rotting

Some dog breeds are more prone to dental problems like rotten dog teeth due to the shape of their mouths and teeth. For example, small breeds and brachycephalic (short-nosed) breeds often have crowded teeth, which can lead to more plaque accumulation and periodontal disease. Left untreated, periodontal disease can lead to rotten teeth.

Older Dogs Are More Prone To Teeth Rotting and Developing Dental Issues

As dogs age, they are more likely to develop dental issues. Older dogs have had more time for plaque and tartar to build up, and their immune systems may not be as strong as it once was. These factors can lead to teeth rotting or infections developing.

Jamie Clanin

A weaker immune system means that your pup’s body is not able to fight off the bacteria that gets under the gums and into the bone as well as it used to, so dental disease moves faster with age.

Dr. Jamie Clanin

Lack of Chewing Can Lead To Less Cleath Teeth

Chewing helps to naturally clean dogs’ teeth. Dogs that do not have access to appropriate outlets for chewing can end up with more plaque and tartar build-up on their teeth.

Underlying Health Issues Can Cause Dogs To Have Rotten Teeth

Certain health problems, such as diabetes and kidney disease, can affect oral health. These conditions can alter the balance of bacteria in the mouth, leading to increased plaque and tartar build-up, as well as rotten dog teeth.

Dogs Can Be Genetically Predisposed To Dental Issues Like Rotting Teeth

Just like humans, some dogs may be genetically predisposed to dental issues. This can affect the strength of their teeth and gums and their ability to naturally combat the build-up that forms.

Oral Infections and Physical Trauma May Lead to Decay and Teeth Rotting

Oral infections and physical trauma to the teeth may also lead to decay and infected or rotten dog teeth. Bacterial infections can weaken the teeth and gums, while trauma, like a cut or injury, can create entry points for bacteria.

Close-up of a dog’s mouth showing healthy, clean teeth and gums. The dog's teeth are white and well-aligned, and the gums appear pink and firm, indicating good oral health. The image highlights the importance of dental care for maintaining a dog's oral hygiene.

Are My Dog’s Teeth Rotting? 9 Signs of Rotten Dog Teeth

1. Bad Breath Is Often One of The First Signs of Dental Problems Like Rotten Dog Teeth

Persistent bad breath is often one of the first signs of dental problems and potentially rotten dog teeth. The accumulation of bacteria in the mouth can lead to tartar buildup around the teeth and gums. You see, the bacteria in your dog’s mouth thrive on food particles stuck between teeth and along the gum line – which can produce foul-smelling compounds, leading to bad dog breath. 

So, if you notice your dog’s breath smells like trash, it could be the first sign of serious dental issues and may indicate rotten dog teeth. 

However, regular brushing and dental check-ups can help mitigate bad breath. Not to mention, regular veterinary dental visits can help discover issues in the mouth early on. Brushing every day (or at least two to three times a week) can help remove debris and bacteria from the mouth, around the teeth, and on the gums. 

2. Discolored Dog Teeth May Be Rotting

Teeth that appear yellow, brown, black, or even pink or purple often indicate tartar buildup or decay. Just like with bad breath – and most dental problems – a lack of proper dental hygiene and long-term accumulation of plaque, which hardens into tartar, can cause tooth decay and discoloration.

Professional dental cleaning may be required to remove tartar and prevent further decay. Regular brushing can help prevent discoloration by keeping ugly build-up at bay. 

In between professional dental cleanings, there are things you can do at home to help keep your dog’s teeth clean. Consider using dental wipes, water additives, or dental powders at home to maintain oral health.

3. Visible Plaque and Tartar

Noticeable plaque (a soft, sticky film) and tartar (hardened plaque) on the teeth are key indicators of rotten teeth in dogs. As mentioned above, inadequate brushing and dental care allow plaque to harden into tartar, which is more difficult to remove.

4. Swollen or Bleeding Gums May Indicate Rotting Dog Teeth

Redness and bleeding of the gums (gingivitis) are never good signs. Bacterial infection from plaque and tartar irritating the gum line can lead to inflammation and periodontal disease – and eventually tooth loss.

Gingivitis can progress to periodontal disease if left untreated. Consult your veterinarian for appropriate treatment and home care recommendations if you notice swollen or bleeding gums.

5. Loose or Missing Teeth

Teeth that are wobbly or have fallen out are sure signs of tooth decay in dogs. You usually don’t have to worry too much about loose teeth or tooth loss when your dog is a puppy, as they’re typically just losing their baby teeth to make room for their adult teeth. 

However, rotten teeth and advanced periodontal disease in adult dogs can lead to the loss of the supportive structures around the teeth.

Veterinary intervention is crucial to address the underlying cause and prevent further tooth loss. Your vet may recommend extractions or other treatments to stabilize remaining teeth.

6. Difficulty Eating or Chewing

Reluctance or struggling to eat, especially hard food, is also a sign of potential dental issues or tooth rot.  If it hurts to eat, your pup may turn their head from side to side or drop their food while eating. Pain from dental decay can make chewing very uncomfortable for your pup.

Softening food, providing pain relief, and seeking veterinary care for a thorough dental examination can help. Switch to a softer diet or moisten dry food to make eating less painful for your dog. Pain management, such as anti-inflammatory medications, may be necessary.

7. Excessive Drooling

Increased saliva production can be a response to dental discomfort. Oral pain and irritation from rotten dog teeth or gum disease can stimulate excessive drooling as the body attempts to soothe the irritation.

Monitor and consult with a veterinarian to determine the cause and appropriate treatment.

8. Pawing at the Mouth or Face

Discomfort from dental issues like decay or abscesses leads dogs to paw at their mouth in an attempt to alleviate the pain.

Seek out immediate veterinary consultation to diagnose and treat the underlying problem. Your vet may need to perform a thorough oral examination, including dental X-rays, to identify and address the issue.

9. Behavioral Changes

Pain from dental issues can affect your dog’s overall mood and behavior. As they try to cope with the discomfort it can make them less playful and, sometimes, more aggressive.

Jamie Clanin

The pain from rotten dog teeth can also cause your pup to slow down in ways that look like old age, but might be fixed with appropriate dental care!

Dr. Jamie Clanin
A close-up of a dog's mouth being examined by a person. The dog's teeth show signs of dental issues, with noticeable plaque and tartar buildup, as well as red, inflamed gums.

Do Rotten Teeth Hurt Dogs?

Yes, rotten teeth can cause significant pain and discomfort for dogs. Here are some reasons why rotten teeth hurt dogs:

Toothache: Just like humans, dogs can experience toothaches when their teeth are decayed. This pain can be constant or triggered by eating, especially if the food is hard or cold.

Gum Disease: Rotten teeth are often accompanied by gum disease, which causes inflammation, redness, and bleeding in the gums. This condition, known as gingivitis in its early stages, can progress to periodontitis, where the gums pull away from the teeth, creating pockets that become infected. This process is painful and can lead to further complications.

Infections: Decayed teeth can develop abscesses, which are pockets of pus caused by bacterial infections. These abscesses can be extremely painful and may cause swelling, fever, and a general sense of malaise in dogs.

Stress: Chronic dental pain from rotten dog teeth can affect a dog’s overall well-being, leading to stress and a decreased quality of life. 

By recognizing the signs of dental pain and seeking timely veterinary care, you can help alleviate your dog’s discomfort and prevent further health complications. Regular dental check-ups and proper oral hygiene are key to maintaining your dog’s dental health and overall well-being.

Can Rotten Teeth Kill a Dog?

Although it isn’t common, if left untreated, tooth-rotting in dogs can be dangerous and have fatal consequences. 

An untreated tooth rot infection can lead to the spread of bacteria to other parts of the body. This can result in:

  1. Systemic Infections: The bacteria from an infected tooth can enter the bloodstream, leading to a systemic infection, also known as sepsis. This can be extremely serious and potentially fatal if not treated promptly.
  2. Organ Damage: The bacteria can travel through the bloodstream and affect vital organs such as the heart (endocarditis), kidneys, and liver. This can lead to severe health issues and organ failure.
  3. Weight Loss: As mentioned above, tooth rot can affect your dog’s ability to eat, leading to weight loss and malnutrition. 
  4. Abscess Formation: Infections can cause abscesses to form. These are pockets of pus that can be very painful and may rupture, causing further complications. Abscesses near the eye or brain can be particularly dangerous.

Rotten Dog Teeth: Final Thoughts

Regular dental check-ups and good oral hygiene can help prevent tooth rot in dogs. If you suspect your dog has a dental issue or shows signs of any of the above, it’s crucial to seek veterinary care immediately. Your vet will be able to determine what action is needed if they suspect something sinister lurking in your dog’s mouth. 

Sources

https://www.akc.org/expert-advice/health/rotten-dog-teeth/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7297050/

Related Reads: Dog Health & Daily Care Guides
Dog Nutrition & Care GuidesDog Health: Signs & SymptomsDaily Supplements: Support for Your Dog’s Wellbeing
Dog Daily Care Guide – Printable Routine Chart5 Health Issues Your Dog Faces Each YearTop-Rated Probiotics for Dogs
The Ultimate Dog Dental Care GuideHealthy Vs. Unhealthy Dog PawsSeasonal Allergy Supplements for Dogs
7 Ways To Support Your Dog’s Immune SystemDog Gut Health: 5 Reasons Why It MattersNatural Probiotics (& Prebiotics) for Dogs
How Much Exercise Does a Dog Need?Healthy Dog Teeth: What’s NormalProbiotic Chews For Dogs – A Simple Hack To Boost The Benefits
Borage Oil For Dogs: Can It Support Skin & Immune Health?Dog Gum Color Chart: Healthy Vs. UnhealthyCan Probiotic Chews Support Dog Gut Health?
Can Dogs Eat Pumpkin?How To Check if Your Dog’s Poop is HealthyPetLab Co. Joint Care Chew Reviews: What Customers Think
Becca TriggB
Written by

Becca Trigg

Becca Trigg is a content creator and pet-industry writer, with over 5 years of experience at PetLab Co. She is an all round animal lover, with a keen interest in canine joint health, dental hygiene and nutrition. When she’s not typing away in the office, she can be found sitting in a country pub, growing chillies or cuddling up with her family dog Maggie, a chocolate Labrador.

Published by