The following is copied from an article by Cristine Travis for Yahoo.

Long Term Health Effects of Dental Problems in Dogs

How Canine Dental Health Affects Overall Health

It's often taken for granted by people that dogs will have bad breath and that their teeth will yellow and even break as the years go by. But the truth is that dogs' teeth are very important to them. Carnivores like dogs have strong, healthy teeth, which means if your dog does not have healthy teeth, it can both be a sign that something else is wrong or can cause more serious problems. Your dog's oral health is one of your best clues about her overall health. Here are some of the ways poor oral health can affect dog overall health:

Periodontitis

Periodontitis is gum disease that results from the build up of plaque and tartar on your dog's teeth. It can lead to loss of bone around the gums and even in the jaws. At the very least, this can lead to lost teeth, but in more serious cases it can lead to severe systemic infections, broken jaws, and problems with the esophagus and swallowing.

Kidney Problems

Many dogs suffer from incontinence, kidney failure, and other kidney-related problems in their later years, and many dog owners believe this is just a natural product of growing old. The reality is that kidney problems can be a direct result of poor oral health. The kidneys filter out many of the toxins in dogs' bodies, and this includes bacteria buildup from minor gum infections and even more severe infections. Your dog may never have symptoms of gum pain and may instead simply develop kidney failure after years of filtering out toxins from the gums.

Heart Problems

Though an actual heart attack is very rare from a tooth problem, tooth infections weaken the heart over time. The bacteria from decaying teeth can get into the bloodstream and repeatedly come into contact with your dog's heart. This means that your dog's life span may be shortened and that, should your dog develop cardiovascular problems later in life, they can be more difficult to treat and are more likely to be fatal.

Nutritional Deficiencies

If your dog has pain in her gums, eating can be painful, which means she may focus on eating only soft foods, which are typically less nutritionally complete. Further, it is tough foods that strengthen dogs' teeth, so avoiding hard foods can create a vicious cycle in which your dog won't eat certain foods because her teeth hurt and the lack of those foods causes her teeth to hurt even more.

Behavior Problems

Any human who's ever had a toothache knows how miserable they can be and how difficult it can be to concentrate on anything but the pain. Dogs can't talk about their pain and can't make a doctor's appointment for themselves, which means they may react with behavior difficulties. Tooth pain can lead to aggression, anxious chewing behavior, housetraining issues, and a variety of other behavioral problems.

Your dogs' teeth are vital to her health, so make sure to take care of them. Get her regular dental checkups; feed her a proper diet and provide her with tough, sugar and carbohydrate-free chew toys.

Source:

Eldredge, Debra, and Delbert G. Carlson. Dog Owner's Home Veterinary Handbook. Hoboken, NJ: Wiley, 2007. Print.