Technology, Hygiene Fight Decay Tooth and Nail

A century ago Americans expected to lose their teeth by middle age.

Now, of course, dentures and old age don’t have to be synonymous. With declines in tooth decay since the 1970s and an emphasis on prevention, fewer people are toothless today than a generation ago--30% of adults 65 or older compared with 46% two decades ago, according to the U.S. Surgeon General’s report on oral health in America. Periodontal disease, commonly called gum disease, is the main cause of tooth loss in adults after age 35. It is an insidious bacterial infection of the gum and the bone, which holds teeth in place.

Growing evidence shows that a healthy mouth should be much more than a cosmetic concern. Bacteria in the mouth and the byproducts of the infection they cause can travel into the bloodstream to other parts of the body. Research published in the Journal of Periodontology in 1998 revealed that periodontal infection might contribute to the development of heart disease; increase the risk of premature, underweight births; and pose a threat to people whose health already is compromised because of diabetes and respiratory diseases.

There is a two-way street between periodontal disease and diabetes. “Diabetics are much more likely to have advanced periodontal disease when they don’t have their blood sugar under control,” said Dr. Kenneth Bueltmann, president of the American Academy of Periodontology, an organization of dentists specializing in diagnosis and treatment of tissues surrounding the teeth. “And diabetics with periodontal disease have a harder time controlling their blood-sugar level.”

Osteoporosis, a bone disorder found chiefly in post-menopausal women, also is a factor in tooth loss.

Women with untreated osteoporosis tend to have less resistance to periodontal disease and experience more bone and tooth loss, Bueltmann said. The mouth teems with bacteria, which cause no problem until the bacteria start to colonize and form dental plaque, a sticky, colorless film that constantly forms on the teeth. It’s the plaque that causes tooth decay and gum disease.

“The bacteria in the mouth need a minimum of 24 to 48 hours to colonize in enough numbers that they start to produce the acid and enzyme systems that destroy the hardest part of your body, tooth enamel, and/or gums,” said Dr. Richard Price, a Boston-area dentist and a consumer advisor for the American Dental Assn.

The recommended artillery is a soft-bristled toothbrush and dental floss. Flossing between the teeth at least once a day and a thorough brushing two to three times a day scatter the bacteria so they cannot build dental plaque, Price said. The mildest form of gum disease is gingivitis, marked by gums that redden, swell and bleed easily. It’s reversible with professional treatment and proper brushing and flossing.

Untreated gingivitis can progress to periodontitis, in which the plaque forces the gum to detach from the tooth, forming pockets that become infected. When the pockets deepen, more gum tissue and bone are destroyed. Eventually, teeth can become loose. Dentists often treat mild cases of gum disease, but severe cases are referred to a periodontist.

“First we get after the causative factors, the bacterial plaque, by good home care and by removing the tartar [hard deposits] where it’s irritating the gums and also causing more inflammation and infection,” Bueltmann said. “As you lose bone around the teeth, these hard deposits start to creep down into the pocket that forms around the teeth. The pocket becomes deeper and much harder to clean.”

A periodontist will clean around the teeth using a meticulous, delicate process called hand scaling and root planing that can require up to an hour for each quarter of the mouth. Even before treatment is started, a periodontist will want to rule out systemic problems such as diabetes, Bueltmann said.

That might require a physical exam if a patient has not had one in a long time. Patients also are counseled about risk factors. “We advise patients to stop smoking and eat well,” Bueltmann said. “Proper diet is important. Calcium and vitamin C intake are important.

“Those with calcium deficiencies have twice the incidence of periodontal disease and more bone loss. Resistance isn’t as great and they lose bone quicker. Those with vitamin C deficiencies tend to have more inflammation.” Smoking, he said, lowers resistance to gum disease. Pack-a-day cigarette smokers have a four times greater risk of advanced gum disease compared with nonsmokers.

If periodontal disease is caught early enough, the deep cleaning and proper home care will considerably reduce the disease process. When patients do not respond to that conventional treatment, antibiotics sometimes are used. Some are squirted into the pockets to reduce the infection, or patients may take them orally.

If cuffs around the teeth are too deep to keep clean, a surgical treatment can reduce them to a more shallow level. The gums are freed (or cut) and repositioned to tighten them back to the teeth, Bueltmann said.

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Various Options for Saving Loose Teeth

If the teeth are loose, there still are options, depending on how severe the situation is.

Bueltmann said that sometimes the teeth are loose not only because of bone loss but also because the bite pressure on those teeth is too heavy. “If the tooth is high on the bite, you can adjust it by shaving on the tooth to get it hitting evenly with the others.”

In an effort to keep teeth from becoming looser, a retainer, called a bite guard appliance or night guard, can be worn while sleeping. Generally worn over the upper teeth, he said, it keeps the upper teeth--usually the ones to loosen most--from being ground on. “When the teeth are loose, there’s a tendency to grind and clench more while sleeping, making them even looser.”

One way of replacing teeth is with dental implants. The artificial, metallic implant is placed in the bone socket where the root of the tooth used to be, and the bone tightens up around the implant. “An artificial crown is placed on top of the implant, restoring chewing and aesthetics. It’s a very effective way of replacing missing teeth, providing there’s enough bone remaining to place the implant in,” Bueltmann said.

Dr. Sab Mukherjee, head of periodontics at the University of Illinois College of Dentistry, called dental implants, which have about a 20-year history, “one major advancement in dentistry to replace lost teeth. The success rate is extremely good so far.” Periodontics also have advanced to the point at which bone can be regrown in certain cases of bone loss around teeth.

Bueltmann said new biotech treatments encourage bone cells to grow and reattach to the roots of the teeth. Products waiting in the wings include “bone morphogenic proteins” that can be placed in isolated areas with a sponge applicator, releasing a growth factor that enables bone to regenerate. It is being tested on humans.

Dentists are learning more about susceptibility to gum disease, and evidence has accumulated showinggenetics play a major role in the onset and severity of the disease. A study published last fall in the Journal of Periodontology showed that in 64 pairs of identical and 53 pairs of fraternal twins, 48% to 59% of the differences in two measures of periodontal disease (gum-attachment loss and depth of pockets) could be attributed to genetics.

When correlating eight clinical measures for gum disease among the two types of twins, all eight measures were statistically significant in identical twins while only two measures were statistically significant in fraternal twins. Asked if some degree of periodontal disease is inevitable as one ages, Bueltmann said: “It’s preventable, so it’s not inevitable. It’s not related to age. Healthy individuals can have healthy teeth and gums. Statistically, older people tend to get more disease because they’ve had more opportunity to have it. But it’s definitely preventable.”