NEWS
10/27/2011 05:45 EDT | Updated 12/27/2011 05:12 EST

Vicious circle: Diabetics prone to gum disease, which can worsen glucose control

TORONTO - People with diabetes are far more prone to developing serious gum disease than those without the disorder, but it's not only tooth loss they need to worry about.

Experts say chronic periodontal disease can also affect the ability to keep blood-sugar levels under control, leading to worsening diabetic symptoms and an increased risk of complications like heart disease, peripheral nerve damage and vision loss.

"People with diabetes are about two to three times as likely to have periodontitis as are people who don't have diabetes," said Dr. Doug Brothwell, associate dean, academic, of the faculty of dentistry at the University of Manitoba in Winnipeg.

"And the complications of periodontitis make people with diabetes about 15 times as likely to lose all of their teeth and to wind up with full dentures," Brothwell said in an interview Thursday.

One reason may be that people with diabetes have a somewhat elevated level of glucose in their saliva that remains on the teeth and gums.

"And that does give a little extra food to the bacteria that grow on your teeth, the biofilm that's present on everyone's teeth," he said. "But it goes quite a bit deeper than that, too."

When the bacteria metabolize sugar from both food and saliva, it produces an immune response that leads to inflammation, Brothwell explained. "That's why people with gum disease, their gums will sometimes get swollen, they'll get red, they bleed a little bit easier."

But it's now known that the inflammatory response isn't confined just to the gums: it can affect other cells in the body and lead to insulin-resistance, the major hallmark of Type 2 diabetes.

"The reaction is a vicious circle," he said. "When you have diabetes, it tends to then make any gum disease that you have worse. As your gum disease gets worse, it leads to an increase in systemic inflammation and your diabetes gets worse again, which in turn makes your periodontitis worse.

"Left unchecked, it will continue on until you either lose some teeth or you have further complications from your diabetes."

Brothwell, in Toronto to discuss the link between diabetes and gum disease at a meeting of diabetes specialists, said people with glucose-control dysfunction need to diligently care for their teeth and gums with regular brushing and flossing to remove bacteria-laden plaque.

"But added to that for people with diabetes and with periodontitis is the added importance of regular dental care."

Regular cleanings under the gums by a dentist or dental hygienist — typically every three months for moderate to severe periodontal disease — can help keep inflammation in check, he said, noting that research has shown that treatment can lead to a 13 per cent improvement in blood-sugar levels, on average.

Dr. David Miller, a Victoria endocrinologist attending the Toronto meeting, said periodontal disease isn't an issue that comes up much in his customary discussions with diabetes patients and he suspects many of his colleagues probably don't routinely ask their patients about it either.

"I describe it as what I call one of the forgotten associations with diabetes," Miller said. "So we spend a lot of time with complications of diabetes that are clearly causative, like kidney disease and heart disease."

But he agreed the issue is an important one and said patients need to keep on top of oral health with regular dental care, in the same way they should routinely see an eye specialist.

Brothwell said tobacco use is also a huge contributor to periodontal disease. "People who smoke get a lot worse gum disease, two to three times as much gum disease as do non-smokers, both with or without diabetes.

"Any patient who smokes should quit, but there's added importance for people with diabetes. By improving the periodontitis, they ultimately may end up with better control of their diabetes."