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Rhonda Arnold dreaded the dentist's chair so much that, despite pain in her jaw, she put off for a year having a cracked tooth repaired.

A dentist had told her that designing, producing and placing a crown over her damaged tooth would require four separate visits to his office, a 90-minute drive from her home.

Arnold couldn't bear the idea of so many dental appointments.

Instead, the Malta woman drove four hours to Billings recently where she had it all done in a single visit.

"It's such amazing technology," Arnold said.

The technology is called Chairside Economical Restoration of Esthetic Ceramics, or CEREC, and is offered in Billings by Turley Dental Care.

"Patients walk out with a crown and ready to chew," said Dr. Christopher Hirt, a dentist at Turley Dental Care. "The convenience factor is huge."

Hirt, Dr. James Turley and certified dental assistant Sandy Rodoni use the technology for about 30 percent of patients who need dental crowns. CEREC won't work in every case, and it probably will never entirely replace the old-fashioned way of making crowns.

But for those who do qualify for the procedure, it can vastly reduce the usual mess and discomfort.

For starters, the technology uses a digital camera to produce images of the patient's mouth.

"Instead of having a mouth full of goop, this takes a digital impression," Turley said.

At Arnold's appointment, Rodoni coated the inside of her mouth with titanium dioxide, a reflective powder that helps the camera capture images. The camera sits on the end of a wand that fits into the patient's mouth.

It sent pictures of Arnold's damaged tooth — much of which had been removed by Turley — to a nearby computer screen. They showed up as a three-dimensional images that could be rotated in every direction. Using the CEREC computer program, Rodoni fashioned a cyber crown for Arnold.

"I have this program loaded on my computer at home, and I practiced at least two hours a night for the first four or five months," she said.

The software drew some of the crown automatically, but some parts had to be filled in or corrected by Rodoni.

"Sometimes when I'm doing this, I'll go and look in the patient's mouth and make sure what I'm seeing here (on the screen) is what's in there," she said.

After she completed drawing Arnold's cyber crown, the computer sent the specs via a wireless connection to a milling machine in another room.

There, a tiny block of ceramic was shaped into a crown. Arnold got to watch the milling process through a window on the machine.

Most CEREC appointments take between 90 minutes and two hours, although Arnold's took a little bit longer because Rodoni ended up redrawing the cyber version of her crown. It didn't look quite right the first time.

"These are going into patients' mouths," Rodoni said. "They need to be perfect."

Turley Dental Care began using the technology about a year ago. It doesn't cost a patient more than does the traditional way of making crowns, which requires a physical impression of the mouth to be made and a dental laboratory to create the crown, Turley said.

Patients must wait days or weeks for traditional crowns to be fabricated and often wear uncomfortable temporary pieces in the interim.

CEREC was developed in 1990 in Switzerland and has been slow to catch on in the dental community in part because it was not very user-friendly when it first came out.

Turley said he expects more dentists to try it as it improves and becomes more affordable.

Contact Diane Cochran at or 657-1287.