SAN FRANCISCO - There is a downside to the overall improvement in oral health: It makes it harder to detect the caries patients do develop.
This is where diagnostic devices that use probes or visual interpretations to check for caries can help, according to John Flucke, DDS, a general dentist from Lee's Summit, MO, who is the technology editor for Dental Products Report and a well-known dental "technophile" who blogs regularly about dental devices.
He shared his thoughts on a number of caries-detection devices on Friday during a well-attended session at the ADA Annual Session.
As oral health has improved through the use of fluoridated water and varnish applications, Dr. Flucke said he's seen fewer "bombed out" teeth, making it harder to detect caries or "silent" areas of decay.
Studies have shown that only 24% of caries are discovered by probing for stickiness, Dr. Flucke said, adding that some dental schools no longer even teach sharp explorer diagnosis. He described a recent case in which one of his patient's teeth looked healthy but turned out to have caries that were 6- to 7-mm deep when he excavated it.
He evaluated two classes of devices: those using probes (KaVo Diagnodent and Midwest Caries I.D.) and those using visuals (Air Techniques Spectra and Acteon Soprolife).
The KaVo Diagnodent uses a 655-nanometer (nm) diode laser to measure caries fluorescence with digital and audible diagnostic indicators for immediate feedback. This helps dentists be more conservative in their treatment decisions.
Dr. Flucke said he tries to save teeth whenever possible. "I'm a John Lennon fan and my motto is: Give teeth a chance."
The KaVo Diagnodent boasts an accuracy rate of more than 90% and recommends restorations at readings greater than 30. But Dr. Flucke said he takes other factors into consideration, including the patient's age, history, and habits.
The Midwest Caries I.D. uses LED technology instead of numerical readings and provides immediate feedback via audio beeps. It detects caries in fissures and on smooth surfaces. The LED light enters the tooth and captures the resulting reflection and refraction of the light in the tooth. Decalcification has a different optical signature than healthy tooth structure, Dr. Flucke explained, and broken down enamel absorbs light differently.
Visualization devices
Dr. Flucke said he prefers the visual devices because they allow him to show patients the color-highlighted healthy versus caries areas of their teeth on monitors.
The Acteon Soprolife requires a computer and emits a light of 450 nm for caries detection. It measures caries fluorescence, which shows up as a glow on monitors; violet indicates caries and white indicates healthy teeth. The Soprolife can be used as an intraoral camera and integrates with Dentrix, Eaglesoft, and other imaging modules.
The Air Techniques Spectra is a caries-detecting intraoral imaging system that utilizes six LEDs and an array that emits a 405-nm light to measure bacterial metabolites called porphyrins. When viewed on computer monitors, healthy enamel appears light green and caries appears red. The images look like Doppler weather radar waves, with different colors showing how deep caries are. The images also allow comparison so dentists can monitor caries development over time.
Both visual devices work like intraoral cameras, use fluorescence detection, and provide image analysis.
Dr. Flucke emphasized that he still uses bitewing x-rays to evaluate caries. "I definitely don't use these devices to make decisions for me," he said.
He also he still uses an explorer, he admitted, "like Linus uses his blanket."
