If your doggy’s breath seems less than fresh lately, there are various reasons behind it, the most common being periodontal disease.

An inflammation of the tissues surrounding a dog’s teeth, it’s caused by the buildup of plaque and tartar, rife with large amounts of bacteria that results not only in bad breath, but potentially in cavities, root infections and gum infections. Treating any or all of these conditions requires a full dental procedure under anesthesia in a vet’s office, while maintaining his now-healthy mouth requires conscientious dental care at home and twice yearly dental exams from then on.

Abscessed tooth roots are also common. The infection produces pus that drains around the affected tooth and into the dog’s mouth, and as the abscess grows, the side of his face closest to the site will start to swell. Sometimes the infection will even break through his skin and the pus will leak onto his fur. An abscess must be lanced and drained by a vet, and more often than not, the affected tooth extracted and the pet placed on antibiotics for several days.

Respiratory viruses are common as well. One of them, the calicivirus, often causes ulcers to appear on a dog’s tongue. While they have a foul smell, most dogs recover swiftly from these infections, and once the ulcers heal, the smell disappears.

Over time, extreme periodontal neglect results in a dog’s gums deteriorating and rotting, causing his teeth to fall out, his gums to bleed and his teeth sockets to develop tumors that emit an extremely vile odor. This dire situation is one that demands immediate veterinary attention.

As dogs age, their kidneys begin to weaken, impairing their ability to filter toxins from their bloodstream. The further this condition progresses, the higher the level of toxins, leading them to develop uremia (the term literally means urine in the blood.) If a dog suffers from kidney disease, his breath will smell strongly of urine or ammonia.

Diabetes can also negatively impact a dog’s breath. While the breath of some dogs has a sweet, fruity smell and others smell like chemicals or acetone, the more obvious signs that something’s amiss are increased thirst, increased urination, and noticeable weight loss despite an increase in appetite.

Bad breath can result from other canine conditions and behaviors -- from the ingestion of toxic plants to pica and coprophagia – as well as from the food they eat. But, given the array of possibilities behind your own dog’s halitosis, always err on the side of caution and have him examined by your vet as quickly as possible if he fails the “smell test.” To determine its underlying cause if one isn’t patently obvious, the vet will take his complete health history, perform a physical exam and, more often than not, order blood tests and a urinalysis, and any other diagnostic tests deemed necessary.

As with the majority of medical issues, though, the best way to “treat” a problem is to prevent it in the first place. And since periodontal disease is the most common cause of canine halitosis, your primary line of defence is a dedicated dental home care routine. This includes brushing your dog’s teeth regularly using a pet-specific toothpaste, starting slowly and rewarding him with positive reinforcement. If this proves too difficult, wiping the outside of his teeth and gums with a Q-tip twice a day is one of the most effective ways of removing and slowing the accumulation of plaque. Last, but certainly not least, feed him a diet that’s especially designed to reduce plaque and tartar buildup, put a capful of an oral rinse in his water bowl and give him dental treats – using only those products recommended by the Veterinary Oral Health Council.