My Dog’s Breath Smells
Bad breath in dogs is not normal. Dental disease causes most of it, but the smell itself can point at the kidneys, liver or gut.
1
Plaque builds up
A soft bacterial film gathers on the tooth. At this stage brushing removes it.
2
It hardens into tartar
Plaque mineralises. Brushing no longer touches it; removing it needs a dental at the clinic.
3
The gum inflames
Red, bleeding gums. The smell comes from bacteria below the gum line.
4
The gum recedes, teeth loosen
The root is exposed and the tooth is lost. It hurts, and animals keep eating through it, so it goes unnoticed.
Brushing only prevents the first stage. Once tartar has formed, cleaning is done under anaesthesia.
Bad breath in a dog is not simply what dogs smell like. It has a cause, and in the large majority of cases the cause is in the mouth.
Dental disease
By far the most common reason. Plaque builds up, hardens into tartar, and the gums become inflamed and then infected. Bacteria under the gum line produce the smell.
By three years of age, a large proportion of dogs have some degree of dental disease. Small breeds are affected earlier and more severely, because their teeth are crowded in a small jaw.
What to look for: brown or yellow deposits along the gum line, red or bleeding gums, a receding gum line, loose or missing teeth, chewing on one side, dropping food, or pawing at the mouth.
Dental disease is painful, and dogs continue eating through a surprising amount of it, so they do not tell you.
When it is not the teeth
The smell itself sometimes tells you where to look.
Sweet or fruity breath, with increased thirst and urination, suggests diabetes.
A smell of ammonia or urine suggests kidney disease.
A foul, sickly smell with vomiting or jaundice suggests liver disease.
A rotten smell in a young dog with no tartar may be a foreign body wedged across the palate or between teeth, a common one being a stick or a bone fragment.
Also: gastrointestinal disease, a mouth tumour, and the habit some dogs have of eating faeces.
What does not fix it
Dental chews, water additives and dry food help slow plaque accumulation. None of them remove tartar once it has formed, and none treat disease under the gum line. If the smell is already there, the tartar is already there.
Brushing does not remove existing tartar either. It prevents new plaque from hardening.
What actually works
A proper dental treatment under general anaesthetic: scaling above and below the gum line, dental X-rays to assess the roots, extraction of teeth that cannot be saved, and polishing.
Anaesthesia free dental cleaning removes visible tartar from the crowns and does nothing about the disease under the gums, which is where the problem is. It also cannot assess the roots.
Afterwards, daily brushing with a toothpaste made for dogs is the single most effective thing you can do. Human toothpaste must not be used; it contains fluoride and sometimes xylitol, which is toxic to dogs.
When to come in
Bad breath that has appeared or worsened. Visible tartar or red gums. Difficulty eating, dropping food, or chewing on one side. Drooling, especially if bloody. A loose tooth or facial swelling. Bad breath with increased thirst, weight loss or vomiting, which points away from the mouth.