There's an Alternative to Traditional Dental Impressions

How Does This New Technology Stack Up?

Photo courtesy of Cadent iTero

Dental impressions are bad enough to make anyone hate going to the dentist. If you've ever needed a crown, bridge or veneer, then you've experienced the agony of a dental impression. There's nothing worse than waiting those two to five excruciating minutes for the gooey material to set.

But it's the 21st century. There's got to be a better way to do dental impressions, right?

The Traditional Impression Alternative

Dental impressions are very common procedures used in dentistry, but if you are one of the many patients that absolutely can't stand to have the traditional impression material (alginate) sit in your mouth, you will be glad to know that there is an alternative.

Digital impression systems, such as the Lava Chairside Oral Scanner by 3M, Sirona's CEREC and the Cadent iTero system, take digital "impressions" of the teeth instead of the gooey impression material that's long been used to obtain the final impression for a crown, bridge or veneer.

Dr. Leonard Tau of the Pennsylvania Center for Dental Excellence introduced the Cadent iTero system into his general dental practice and experienced some positive results.

"It eliminates the goopy dental impression material that causes patients to gag and not enjoy their visit," says Dr. Tau. "It also allows for a better-fitting final restoration, which in turn allows for a faster appointment, and the patient thus spends less time in the dental chair."

When your dentist has completely prepared the teeth that require restoration, a wand is used to take a digital image of the teeth. Dr. Tau explains that taking a digital impression of prepared teeth takes approximately a minute and a half, and an impression of the teeth in the opposite arch takes a mere 45 seconds.

Pros & Cons of Digital Impressions

How accurate is iTero? According to Dr. Tau, very.

"The iTero digital impression system creates an exact replica of what is in your mouth. This results in a more accurate-fitting crown or bridge. I have never had restorations that have fit better."

However, researchers are still looking into the technology's efficacy.

A 2008 article published in the Journal of the American Dental Association (JADA) determines that digital impression systems are a promising technology, but additional research is still necessary in order to fully distinguish the pros and cons between the two impression-taking methods.

One of the most common areas of concern when creating a crown, bridge or veneer involves the tiny space between the tooth and the gum tissue that surrounds the tooth, known as the subgingival margin. Without an accurate imprint of this area, the final restoration may not fit the tooth appropriately, resulting in a myriad of problems down the road.

The JADA article notes that digital impression technology won't necessarily improve the final impression's outcome, and there is still a need for the most careful isolation of the soft tissue prior to taking the digital impression.

Keep in mind that not every dentist utilizes this type of digital impression technology. Many dentists prefer using traditional methods because there is not enough research that suggests digital impressions are superior.

This kind of digital technology also comes with a big price tag some dentists can't justify.

Other dentists that have switched to digital impression systems would never consider turning back, like Dr. Tau.

"[My] patients love the iTero, especially the patient who cannot take a dental impression due to a severe gag reflex," Dr. Tau says. "If you have ever had a conventional impression taken, you know just how uncomfortable the process is. The putty is messy, tastes extremely unpleasant and in many patients can cause gagging."

Patients interested in learning more about digital impression systems should speak to their dentist about this technology.


Interview with Dr. Leonard Tau of The Pennsylvania Center for Dental Excellence. November 18, 2009.

Will Digital Impressions Eliminate the Current Problems With Conventional Impressions? J Am Dent Assoc, Jun 2008; 139: 761 - 763. Accessed: December 9, 2009.

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