CEDAR FALLS -- Christy Twait schedules her dental exams as early in the week as possible.

If she's unlucky enough to draw a Thursday or Friday appointment, the Hudson woman is a bundle of nerves by checkup time.

"I shoot for Monday, as early as possible," she said. "Otherwise, I'll be worrying about it all week."

But this summer, Twait learned to relax -- at least a little -- in the dental chair. Her secret? Tuning in to a handheld audio sedation device. Her dentist, Dr. Ken Budke of Cedar Falls, came up with the idea. The tool, called b-Calm, blends the frequency of the dental drill with recordings of nature sounds.

"I used to just stiffen up when I heard the drill," said Twait, who listened to the handheld player Monday as she got a crown replaced. "I'd clench my fists and my legs would go straight. ? Now I just hear the waves crashing and I can pretend I'm at the beach."

The b-Calm device, released in January, will soon be marketed throughout Iowa. Budke hopes that dentists across the country will be exposed to his invention within a year.

"This is something that can help make patients more comfortable at the dental office," said Budke. "If people are afraid to go to dentist, they end up ignoring preventive care and wind up coming in on an emergency basis, which is more costly and often more painful."

The audio gadget resembles a hand-held MP3 player, but is much more effective at drowning out unpleasant sounds than an iPod, said Curtis Carroll, an Ankeny mechanical engineer who made Budke's idea reality and designed the device.

"Listening to music actually involves a lot of mental participation; it goes up and down -- you have to think," he said. "For b-Calm we looked for sounds that would transport patients somewhere else while cutting out the noises of your typical dental office."

Patients listen using disposable ear buds. Four buttons allow the user to select a sound file and control the player's volume. Auditory get-aways include a windy forest, rustic barnyard and tropical beach. The device costs around $500.

Since its release, b-Calm also has been tested outside dentistry. Some doctors have distributed the device in maternity wards, and a few educators and parents are using the players to keep children with autism and attention-deficit/hyperactivity disorder on track in the classroom.

"It helps them isolate and calm their minds," Carroll said. "They've found they can better focus on their schoolwork."

Budke, a dentist for 36 years, is happy is see new applications for his product. Still, he takes the most joy from seeing b-Calm alleviate the fears of apprehensive patients like Christy Twait.

"She still doesn't like coming here," Budke said, offering Twait a one-armed hug after her appointment. "But it's not as much of an ordeal as it used to be, and that makes me happy."

Contact Mary Stegmeir at (319) 291-1482 or mary.stegmeir@wcfcourier.com.