Shedding new light on dental caries: the latest technology allows dental hygienists to track changes in the health of each tooth, revealing troubled areas early in the formation of caries.

If Jackie Derwingson, RDH, BS, had been told about an early caries detection device when she graduated from dental hygiene school in 1968, it would have seemed space age, she said.

"I could never imagine using [this type of equipment]. We didn't even wear gloves then!" said Derwingson. Almost 40 years after Derwingson graduated, fourth-year dental hygiene student Sarah Chase received training on a dental caries detection device as part of her educational program.

"I like that I can confirm my own suspicions of a carious lesion with the DIAGNODent before I consult the dentist about my findings," the student commented. "As a student dental hygienist, it gives me more confidence in my detection to know that the reading also matches my conclusion."

"[New technology] has made practice more interesting," Derwingson continued. "We're much more proactive now. When I graduated [in 1968], only 50 percent of the patients over 60 years old had their own natural teeth. Now that is 80 percent." Early detection, along with preventive action, ensures that the next generation maintains this high standard of oral health.

Caries detection equipment "reads" the status of the dentin for existing or potential carious lesions. Most systems have a number scale or some other method of measurement to rank troubled areas. The systems also include software and/or printed sheets to track how those areas change from check-up to check-up. See sidebar, page 41, for details on how each system operates. These devices may be used on young and old alike and offer particular advantages for younger patients and those with a history of being difficult to X-ray.

Shari Williams, RDH, described patients who may be helped by such a device as "somewhere between six and edentulous." As part of her work as an instructor for Eastern Washington University, Williams helps students read X-rays and check for potential carious lesions using the DIAGNOdent caries detection system. The students then present this information to the dentist at the time of the chair-side exam.

"The DIAGNOdent is a very valuable tool when used in conjunction with radiographs and a visual exam," commented Williams. "You can 'watch' potential lesions by recording the readings at each recall appointment."

DIAGNOdent readings of 25 or more, when confirmed by the dentist's exam and radiographs, according to Williams, are considered carious lesions. Below 25 are still sealable when all diagnostic avenues are followed and confirmed. Readings of 19 and below usually can be sealed. She also recommended testing all stained and sticky occlusals when the dental hygienist is unsure of the presence of caries.

"The DIAGNOdent is helpful in making patients aware of potential lesions," Williams continued. The device is equipped with audio capabilities that transmit louder beeps as it encounters troubled areas. "The louder 'noise' transfers to a greater urgency in dental care and home care," Williams stated. "Detecting early lesions and sealing out further bacteria [are] extremely advantageous to at-risk youth and adults who have poor homecare."

Incorporating New Technology into Exams

How has this state-of-the-art technology changed the average oral health check up?

"It's more thorough," said Victoria Fedor, RDH, who uses the DIAGNOdent on children as a screening device and as an adjunct on adults. "Sometimes I will just [move the device] over the occlusal surfaces as part of the exam. If I see something suspicious on adults, I will use the DIAGNOdent to validate [my concerns there]," said Fedor, who has used the equipment for three years.

Because the dentist with whom she works feels that Fedor has more time to review the whole mouth, she relies on Fedor to write down any suspicious areas and use the DIAGNOdent when applicable.

"We then discuss the patient's history, diet and oral hygiene whether [a sealant or composite should be placed]," added Fedor, who described the practice in which she works as forward-thinking in the area of new technology. "We were one of the first offices in New Jersey to get digital X-rays, and my boss does laser and Cerec dentistry (by Sirona Dental Systems, the one-day ceramic restorations). Those are new techniques here.

"With the DIAGNOdent, you know whether or not something suspicious is decay," Fedor continued. The dentist confirms decay using Fedor's findings with the DIAGNOdent, X-rays and with clinical probing.

The practice in which Jaime Aucoin, RDH, works uses the DIFOTI caries detection system. She checks suspicious sites with the DIFOTI camera and with X-rays. "The device shines a light through the tooth," Aucoin explained. "Any areas of decay show up darker than surrounding tooth structure. On a virgin tooth, you can see decay beginning in stained grooves."

At that time, Aucoin informs the patient that she will specifically point out those troubled areas to the dentist. "The nice thing about this camera is that it shows stress fractures around amalgams and also decay beginning around the edges of the amalgam," Aucoin reported. "It really only works best if the amalgam is a shallow restoration. [The system] also works with composite material."

In the practice in which Derwingson works, all new patients are seen by the dentist and receive a DIAGNOdent screening on the first visit. At subsequent visits, the dental hygienists re-screen teeth that haven't been restored or haven't had sealants put on them to see if the readings change.

"Sealants have been around for a long time, but there was always that concern that you were sealing over some decay that couldn't be seen because it hadn't shown up on X-ray yet," Derwingson explained. "The tooth has to undergo a certain amount of change before it shows up on X-ray. The DIAGNOdent can pick it up at a much earlier stage." This allows for more minimally invasive dentistry, she continued.

As mentioned before, Chase uses a caries detection device as part of her educational program. "I take DIAGNODent readings for every new patient as a baseline number to compare their enamel health as they continue to be my patient. I also use the DIAGNODent before placing sealants and to evaluate teeth [that] I believe have a carious lesion in them before consulting my dentist and instructors," said Chase.

"It's a simple process, only involving a few steps for the whole detection process. I really like that I can have clear readings, and that I can then have a baseline reading for each patient. It really helps assess the patients' continuing oral health," Chase commented.

Advice for New Users

Fedor and other dental hygienists contacted for this article concluded that dental practices that purchase this equipment should be prepared to spend some time learning about the device and practicing with it on each other before putting it to use on patients. Fedor stressed the importance of dental hygienists allowing for the learning curve that accompanies gaining knowledge of this equipment.

Williams expressed concern about how caries detection devices are used. She urged dental hygienists to consider it as a tool and not a total answer. It is important, she asserted, to consider the procedure and process the number values provided by the equipment.

"I have seen RDHs and dentists disregard the very specific directions and diagnose without the back-up of radiographs or visual examination," Williams described, adding that users who choose not to follow the equipment's directions may get false readings. "Until the clinician is competent with it, the process is cumbersome and frustrating to many," Williams said.

"There are a few ways to get a false reading on the DIAGNODent," confirmed Chase. "If you don't have all the saliva removed or the polish brush didn't get into the crevices, you will get a false high number, which can be difficult to determine if you already suspect a carious lesion. Also, calibrating the machine can be a little tedious and can be difficult if the machine won't accept the readings of the calibration for whatever reason."

Dental hygiene student Chase received training on the caries detection device in-office by professors in her education program after watching the manufacturer's video.

"It was helpful to see the video first and then have a hands-on demonstration of the technique," she said, noting that the calibration process was slightly different from the video.

After viewing the manufacturer's video and thoroughly reading the instructions and trouble-shooting material for the DIAGNOdent, Williams condensed the information onto a half-sheet of paper and laminated it as a quick reference teaching guide for the students and other faculty.

"I believe every clinician should practice on each other before they apply it in a clinical setting," said Williams. "The entire office staff needs to be calibrated on which number values to use."

Aucoin agreed that caries detection devices cannot be used right out of the box without careful attention to the instructions and a little practice with the device.

"I really feel that you as the operator of the device have to be comfortable with the equipment," said Aucoin. "I came into this office with the DIFOTI already being there. The tutorial really doesn't show you how to use it, it just shows images of what cracks, fractures, stain and decay look like." Aucoin has found that she doesn't care to use the device because of the ergonomic challenges of the model in her practice. She describes the handpiece as long and heavy, and the mouthpiece as somewhat large. She commented that it is difficult to fit even the pediatric mouthpiece in a child's mouth.

"It has to be to be able to fit around a molar, so I don't know if that is something that could be modified," she noted, adding that a lighter, swivel cord on the bottom of the handpiece would be a good product modification.

"The only camera I ever liked was a cordless intraoral camera," Aucoin commented. "There was no program to enter; I just turned on the monitor and the camera and started to take pictures." She noted that the DIFOTI camera feature was an asset to the practice in that it helped educate the patients about what amalgams can do to the teeth and when it is appropriate to have them changed.

This new way to monitor a patient's oral health was important to Chase. "I think that especially having a baseline figure has really helped my clinic to have better evaluations, and provide information that we may not have had before," she commented. "The information helps us create better treatment plans, give more comprehensive exams, and is an important part of our patient's dental health record," she continued.

Fedor advised those interested in caries detection equipment to call their dental representative and try it on a demo basis.

"If you're not comfortable using the equipment, it's just going to sit on the shelf. It takes some time to adjust to using it," Fedor concluded. "It really helps you diagnose better. It is validation for areas that we as clinicians are uncertain about."

Differences in Caries Detection Devices

No two devices operate the same way. These helpful descriptions, culled from the manufacturers' Web sites, offer a glimpse of each operating system. For more detailed product information and specifications, visit each company's Web site or contact a sales representative.

D-Carie Mini (Neks Technologies, Inc.)

The D-Carie mini is a lightweight, easy-to-use, cordless device that can be used as an aid for clinicians to quickly locate and diagnose caries. The D-Carie mini uses Light Emitting Diode (LED) and fiber optic technologies to accurately detect both occlusal and interproximal caries. The device requires no calibration and is easy to sterilize. To use, the clinician maintains contact with the tooth surface. The presence of both occlusal and interproximal caries is identified by two signals: audible and visual (green light turns to red). Effective in a wet environment, the device requires only an initial plaque removal prior to use. For more information, review the company's Web site at http://www.neks.ca/mini_en.htm

DIAGNOdent 2095--Laser Caries Detection Aid (KaVo Dental Corporation)

DIAGNOdent measures the laser fluorescence within the tooth structure. Altered tooth substances and bacteria fluoresce when they are exposed to a specific wavelength of light. At a specific wavelength, clean healthy tooth structure exhibits little or no fluorescence, resulting in very low scale readings on the display. However, carious tooth structure will exhibit fluorescence proportionate to the degree of caries, resulting in elevated scale readings on the display of the DIAGNOdent. An audio signal allows the operator to hear changes in the scale values. This enables the focus to be on the patient, not solely on the device. Reproducible results permit checking, stabilization and documentation of caries. For more information, review the company's Web site at http://www.kavousa.com/ products/handpieces_accessories/special_instruments/ diagnodent/diagnodent.asp?navid=311000&lan=Us

Digital Imaging Fiberoptic Transillumination (DIFOTI)

The Digital Imaging Fiber-Optic Trans-Illumination (DIFOTI) disposable mouthpiece, after being placed over the proximal surface of the tooth in question, shines white light from one surface through the tooth and is captured on the opposite side using a CCD camera in the DIFOTI handpiece. The occlusal surface mouthpiece illuminates the tooth at angles through both the facial and lingual surfaces and images the light emerging from the top of the tooth. A high-resolution image appears instantly, in real time, much as it would with a video camera, on the computer monitor. A hygienist can place DIFOTI on one tooth and image in three seconds or take a full-mouth set of images in a matter of minutes. Decay near the imaged surface appears as a darker area against the more translucent brighter background of surrounding healthy anatomy. DIFOTI produces high-contrast images of decay on all tooth surfaces. For more information, review the company's Web site at: http://www.difoti.com/about_difoti.htm

LOGICON Caries Detector[TM] Software (Kodak)

LOGICON Caries Detector[TM] Software exposes cavities extending into the dentin, assisting in the difficult task of diagnosing radiographs for proximal caries. An optional component with KODAK RVG digital radiography systems, LOGICON software is a computer-aided-detection tool that provides dentists an important decision-support instrument for better patient care. It uses detection algorithms based on laboratory data produced in association with a leading school of dentistry. It automatically outlines a potential lesion on the tooth image and graphically presents change in tooth density and lesion probability. For more information, review the company's Web site at: http://www.kodakdental.com/EN/ imagingSoftware/windows/addOnModules/logicon. html?pID=8010

Jaime Matherne Aucoin, RDH graduated from Louisiana State School of Dentistry with an Associate of Science Degree in Dental Hygiene. She been practicing for nine years and currently works in her home town. She is married and the mother of two daughters.

[ILLUSTRATION OMITTED]

Sarah Chase is a fourth-year student at the University College of Bangor which is part of the University of Maine, Augusta. She will be graduating with an associate's degree in dental hygiene in May 2008. Before deciding to major in dental hygiene, Chase completed two years as a premedical studies student at the University of Maine in Orono. When she graduates, Chase plans to return to the MidCoast Maine area to work as a dental hygienist for a few years, while completing classes for her bachelor's degree. She would like work as a dental hygienist with a missions group in a third-world country.

[ILLUSTRATION OMITTED]

Jackie Derwingson, RDH, BS, has a Bachelor of Science degree from the University of Southern California. After relocating to Northern California, she became the first dental hygienist in Southern Siskiyou County. She now practices in the only state-of-the-art dental office in the area. Her passion for travel has taken her to destinations worldwide with her travel consultant husband. They live at the base of 14,162-foot Mount Shasta and enjoy an abundant recreational lifestyle that includes hiking, biking and kayaking.

[ILLUSTRATION OMITTED]

Victoria Fedor, RDH, has been a practicing dental hygienist for 27 years. A graduate of Middlesex County College in 1983, Fedor has been an active member of ADHA for more than 10 years and is a past president of the New Jersey Dental Hygienists' Association. She also has served as an ADHA delegate. Married to husband, Anthony, for 17 years, she has two sons, Nicholas and Stephen. She currently works full-time as a clinician in a general practice in Manahawkin, N.J.

[ILLUSTRATION OMITTED]

Shari Williams, BS, RDH-EA has been a practicing dental hygienist and a clinical instructor at Eastern Washington University for 24 years. The inventor of CHUB-EZE instrument grips, she has been a member of ADHA and Idaho Dental Hygienists' Association since 1981 as a student and has held numerous state offices including 2 terms as IDHA President and 5 years as IDHA Delegate to ADHA, 1984-1989. Shari serves on the Maxillofacial Cleft Palate Review Board in Coeur d'Alene, ID, and is currently employed at Dirne Dental Clinic in Coeur d'Alene. She is leaving for Kenya to establish a dental care program teaching African students how to care for children's oral health.

[ILLUSTRATION OMITTED]