What causes halitosis in dogs?
Halitosis is an offensive odor coming from the mouth. Halitosis can be caused by:
- Bacteria associated with plaque and/or tartar
- Decomposing food particles retained within periodontal pockets
- Persistent bleeding due to coagulation abnormalities
- Tissue death from oral tumors
The most common cause of halitosis in dogs is periodontal disease arising from plaque (biofilm) and tartar build-up. The plaque biofilm forms over a freshly cleaned and polished tooth as soon as the dog starts to salivate. Within days, the plaque becomes mineralized, producing rough tartar (calculus) which accumulates more plaque and causes gum inflammation (gingivitis).
As plaque ages and gingivitis progresses into periodontitis (tooth support loss), the bacterial flora changes from good bacteria to destructive bacteria.
"The most common cause of halitosis in dogs is periodontal disease arising from plaque (biofilm) and tartar build-up."
The primary cause of bad breath in dogs is bad bacteria causing decay that creates smelly sulfur compounds. Volatile sulfur compounds may also play a role in periodontal disease, affecting the integrity of the tissue barrier, allowing endotoxins (a part of bacteria) to produce periodontal destruction, endotoxemia (endotoxins in the blood), and bacteremia (bacteria in the blood).
Small and flat-faced breeds are more prone to oral disease because the teeth are closer together. In addition, smaller animals live longer, and their owners tend to feed them softer food.
How is halitosis treated?
Treatment of halitosis in dogs involves eliminating the cause(s). First, a thorough examination of the entire oral cavity is necessary. Then the teeth must be thoroughly cleaned and polished under general anesthesia (see handout "Dental Cleaning in Dogs" for more information).
Cleaning removes plaque and tartar (calculus) above and below the gumline (with the help of hand instruments and scaler tips designed to be used under the gumline).
After teeth cleaning, a tooth-by-tooth examination is conducted. Intraoral dental X-rays are inspected to assess structures beneath the gumline. Often, those teeth affected by advanced periodontal disease need to be extracted.
How can halitosis be prevented?
After the causes of halitosis have been identified and eliminated, daily plaque control is an essential part of controlling halitosis and preventing it from recurring.
Fortunately, there are products available that decrease the accumulation of plaque once the teeth are clean. The Veterinary Oral Health Council only accepts dental products that are safe and proven to reduce the accumulation of plaque and tartar, based on scientific studies. These products include dental diets, treats, water additives, and topical applications. Accepted products are listed at VOHC.org, or ask your veterinarian for recommendations.
"Dental examinations at least twice a year are recommended to help treat and prevent halitosis."
Oral care products containing metal ions, especially zinc, can inhibit the formation of odor through their natural attraction to sulfur; zinc and hydrogen sulfide combine to form the insoluble compound zinc sulfide. Zinc also interferes with microbial growth and calcification of microbial deposits that can cause halitosis.
Dental examinations at least twice a year are recommended to help treat and prevent halitosis.
