Diagnose, monitor and manage caries with KaVo's DIAGNOdent Pen

According to the National Institute of Health’s Consensus Conference on the Diagnosis and Management of Dental Caries throughout Life, “Dental caries is an infectious, communicable disease resulting in destruction of tooth structure by acid forming bacteria found in dental plaque, an intraoral biofilm, in the presence of sugar.

The infection results in loss of tooth minerals that begins with the outer surface of the tooth and can progress through the dentin to the pulp, ultimately compromising the vitality of the tooth.”

It has been more than a decade since this statement was made, yet the vast majority of practices throughout the world still use the word “watch” in regards to carious lesions that are evident in our patients’ mouths. This most likely stems from traditional GV Black Dentistry. When alloy was the primary restoration of choice, clinicians often watched a lesion progress over many months or even years before surgical intervention commenced. Because alloy needed very specific architectural form, it did not make sense to surgically intervene until the volume of caries justified the architectural form.

Caries, as we know it today, is a disease process that can be managed. Clinicians should be aware of technological advances that help them diagnose caries as well as the technological advances that allow them and their team members to actively monitor and manage the caries process.

Detection
To actively manage a disease process the disease must be detected first. Historically caries detection occurred via a visual assessment as well as a tactile assessment. Tactile assessments are generally carried out by probing the tooth’s occlusal surface. If the dental explorer binds or sticks within a pit or groove, it’s common to deem the groove carious. Probing an occlusal surface tends to have very high specificity (when the explorer sticks, there tends to be decay), in that false positives tend not to occur.

The unfortunate part of tactile detection is caries can be missed quite frequently. In a 1992 study C. Penning and colleagues demonstrated that tactile detection may only discover 24% of caries that exist within a tooth. Therefore 76% of the time caries goes undiscovered and the disease process progresses.

Since this 1992 study a more prescribed visual detection protocol called the International Caries Assessment and Detection System (ICDAS-II) was developed. In this system you only use the dental explorer to wipe plaque away from the occlusal surface; it is not used in a penetrating manner. The ICDAS-II system scores each occlusal surface on a 0-6 scale, with higher numbers indicating greater disease progression. The ICDAS-II system tends to show fairly high specificity in the 82-94% range and moderate sensitivity in the 59–83% range.

Essentially when clinicians use the ICDAS system appropriately they tend to have relatively few false positives; however decay can be missed between 17–41% of the time. This visual detection system tends to be substantially better than probing, though caries can continue to stay hidden and progress.

In addition to visual and tactile detection, radiography also has been used for caries detection. Generally speaking radiographic detection is successful in detecting approximal caries and only shows moderate results in terms of occlusal caries. Bitewing radiographs tend to miss early occlusal carious lesions nearly 70% of the time, but they tend to show very few false positives.
Diagnosing early carious lesions can be very difficult; practitioners must properly use a combination of all of the aforementioned techniques, so a patient’s disease process can be properly managed and treated when appropriate. To help with this difficult diagnosis, clinicians also can turn to technologies developed to aid in diagnosis, such as KaVo’s DIAGNOdent Pen.

What it is
The DIAGNOdent Pen is a laser fluorescence caries detection system that measures fluorescence of sound tooth structure compared to demineralized tooth structure. The DIAGNOdent Pen illuminates the tooth surface using a diode laser with a wavelength of 655 nanometers. As the laser enters the tooth surface it causes porphoryins and other chromophores to fluoresce. The DIAGNOdent system captures and analyzes this fluorescence. Porphoryins are given off as metabolites of bacteria, responsible for the carious process. Researchers have shown that porphoryins could be extracted from caries lesions and are useful in distinguishing sound tooth structure from caries affected teeth.

The DIAGNOdent system is accurate at finding caries when it indeed exists. The DIAGNOdent system has been studied extensively and the studies generally show it has a very high sensitivity rate as well as a high specificity rate when used on non contaminated surfaces. DIAGNOdent at times may show a false positive reading when an occlusal surface is contaminated with calculus, plaque, prophy pastes or other foreign materials. These debris should be cleaned off prior to scanning.

Proper use and implementation
Dentists should use caries detection technology, and while many fine caries detection systems exist in the marketplace, DIAGNOdent Pen stands out to me. It is a portable solution that does not need additional computer integration. Visual caries detections systems require a personal computer to display the caries analysis photo. In comparison the DIAGNOdent Pen offers a digital readout built into the device and a high pitch audible tone when demineralization is detected.

Technology integration is most successful when team members participate in using and implementing the technology. To that end I believe the DIAGNOdent Pen system is best integrated within the hygiene visit. Each occlusal surface should be scanned when patients come in for their hygiene and periodontal examination visits, but only after being thoroughly cleaned and dried. The DIAGNOdent Pen’s tip should trace the occlusal grooves and pivot buccal and lingual, so the grooves are examined in all dimensions. This information should be recorded and the data provided to the dentist as one aspect of the diagnostic tests. Areas that show calibrated readings above 30 should be looked at closely in conjunction with the ICDAS assessment, radiographic evidence, as well as caries risk assessment and a determination should be made if minimal surgical intervention is warranted (Fig. 1).

The benefit
This early detection allows for a conservative surgical approach that simply removes the diseased tooth surface (Figs. 2 and 3). Once the disease is removed you can place a small resin restoration and maintain significant amounts of healthy tooth structure (Fig. 4). If you decide to hold off on surgical intervention, you can still share the information obtained from the DIAGNOdent Pen with the patient, which enables you to partner together for an active management approach.

In the active management approach you and your team members instruct the patient on proper hygiene and dietary habits. Place the patient on home care products that help manage the disease process, such as fluoride rinses, fluoride toothpastes, xylitol, chlorhexidene and amorphous calcium phosphate pastes. Recheck these patients at future visits, and only opt for surgical intervention if digital and visual detection warrant it.

The ultimate goal is for dentists to manage caries as a disease. If and when surgical intervention must occur, technology such as the DIAGNOdent Pen will allow for minimally invasive preparations, so vast amounts of healthy tooth structure are preserved.