ANXIOUS GNASHING OF TEETH\Patients reduce stress, habits that can become a real grind.

Byline: Diana E. Lundin Daily News Staff Writer

Carlene Laird has been grinding her teeth at night for so many years, she even remembers as a child her mother telling her the grating noise traveled through walls, waking both her parents.

"My mother said it would wake them up out of a sound sleep," said Laird, 65, of Sherman Oaks. "I didn't realize I was doing it."

So it came as little surprise to the retired legal secretary to learn, then, that stress is a major contributor to her teeth grinding. "I've been an uptight person forever," she said.

In a stress-filled world of traffic jams, job insecurity, random violence, credit card debt and Newt Gingrich, it isn't any wonder that more and more Americans are transferring their pressures onto their enamel.

"As stress increases, some people grind their teeth; some people chew their fingernails," said Dr. Gary N. Herman, a North Hollywood dentist and president of the San Fernando Valley Dentists Society, a component of the California Dental Association. "You've got to relieve the stress somehow."

For many, it's a learned behavior.

"You do it a little during the day, clench your teeth on the freeway when you're stuck in traffic," said Dr. Michael Simmons, an Encino dentist who lectures at the School of Dentistry at the University of California, Los Angeles. "Holding that tension in your jaw muscles may be something you learn and continue doing it. And then you start doing it in your sleep."

Up to 95 percent of the population grinds its teeth at night at some time or other, according to Chris D. Martin, spokesman for the Chicago-based American Dental Association. "The question is, of those 95 percent, how many have adverse health effects? Maybe 5 to 10 percent," he said.

Left untreated, bruxism, as dentists call it, can alter a person's appearance by wearing the teeth down - usually the canines and incisors because of their steeper inclines. At some point, the front teeth are so damaged, they no longer protect the back ones, dentists say.

"When someone puts a lot of force on a tooth, it doesn't have many options, does it?" Simmons said. "It can break, move, get loose or wear down."

Grinding also leads to progression of gum disease, and temporomandibular joint (TMJ) disorders that can lock the jaw (see accompanying chart).

At one time, dentists believed bruxism was caused by a misalignment of the teeth, Simmons said. "Research has not supported that point of view, although it was a very popular approach in the '60s and '70s. It's more related to stress issues and less related to the way teeth mesh," he said.

But dentists aren't quite ready to conclude that it's just because we seem to have more stress in our lives. After all, teeth grinding was recorded as far back as biblical times.

"What has really happened is that dentists are more aware of it than ever before," said Dr. Lucia Paxton, a Tarzana dentist who estimates that up to 80 percent of her patients grind their teeth. "Patients have never been aware of it. What's changed is we're detecting it earlier. We just weren't looking for it as much before."

Though dentists can't treat it, they can at least try to prevent the damage.

According to an article in the Journal of the American Dental Association, dentists are prescribing 3.6 million nightguards annually, adding up to about $1 billion a year - much of it not covered by insurance.

Priced at an average $200 to $300, these appliances are made by taking impressions of patients' teeth, then constructing a hard acrylic appliance that fits in their mouths. Worn at night, they prevent the teeth from striking each other.

Laird was fitted with the nightguard after Paxton found evidence of her longtime teeth-grinding habit. Her husband, Milt, knew something was up because he could hear her nocturnal gnashings, which he described as something akin to crunching on peanut brittle.

Then, her teeth began hurting.

"That's when I got a nightguard," she said. "Now, when I wear that, I sleep a billion times better."

So does her husband.

Whether dentists can get their patients to wear the nightguards is another issue, Herman said.

"If their jaw hurts and we make them one of these appliances, they're very good at compliance," Herman said. "Compliance is much less good if the problem isn't so obvious to the patient."

Grinding ceases immediately for a certain percentage of patients for whom Herman prescribes the devices. Another percentage of patients still grind, but the nightguard's plastic is damaged - it wears and the teeth don't.

But for another group of patients, forget it. "They are just physically or subconsciously unable to wear the thing. They wake up in the morning and it's not in their mouth and they don't know why," Herman said.

Because stress plays such a starring role in teeth grinding, the ADA said some patients should consider counseling to alleviate their daily tensions, muscle relaxants to ease clenched jaws or physical therapy to relieve muscle pain.

Here are other tips from the ADA to prevent grinding:

Place reminders around the house, or try repeating phrases that help you relax.

Apply a warm washcloth to the side of your face to help relax clenching muscles.

Cut down on caffeine, take warm baths and ease up on yourself to reduce stress.

Ed Potter, 59, of Bear Valley Springs suffered from thermal sensitivity with his three-decade-long habit of grinding. He thinks it was exacerbated by his years as an elementary school principal and superintendent.

"Any change in temperature, hot or cold, was very painful," said Potter, now retired and living in the Tehachapi Mountains, 50 miles north of Lancaster. "I thought my filling was going bad."

As it turned out, that was the least of his problems. Slowly, Potter wore down his molars and lost an eighth of an inch from his front teeth, which later had to be capped.

"I had done a pretty fair job of destroying my teeth over the years," he said. "I was unaware of it. It took some changes in my facial appearance and some rather severe pain to convince me that something needed to be done."

Since getting his nightguard, Potter is faithful about wearing it. On occasion, he forgets to slip it in. "Until I lay down. Then I'm very aware I don't have it in," he said. "I have worn some serious grooves into it. Evidently, I'm still grinding my teeth, even though I'm not damaging them."

Denise Goodwin, a 28-year-old dental assistant in Simmons' office, started grinding her teeth shortly after a car accident more than a year ago.

"I was a little stressed," said Goodwin, who lives in Mission Hills. "It started right after that. I'd wake up and my jaws would be really sore. I was getting flat spots on my teeth. I would clench and grind them at night."

Once she realized what she was doing, she asked her boss for a nightguard. "I love that thing," she said.

The pain has gone away and her teeth are no longer wearing down. But best of all, she gets a good night's rest. "I used to wake myself up in the middle of the night grinding," she said. "I don't do that anymore."

CAPTION(S):

DRAWING[ordinal indicator, masculine]PHOTO[ordinal indicator, masculine]CHART

Drawing (Cover--Color) IT'S A GRIND Blame that nocturnal gnashing on a stress-filled world Photo Tarzana dentist Dr. Lucia Paxton holds a nightguard she prescribes for some of her patients. She estimates that up to 80 percent of her patients grind their teeth. David Sprague/Daily News Box TMJ The phantom pain Knight-Ridder Tribune Graphics Network