Early Detection and Treatment of Caries

CBCT allows dentists to acquire a highly accurate 3-dimensional image of the patient's anatomy from a single scan. This facilitates a better diagnosis and understanding of the true extent of dental disease. The traditional use of 2D radiographs for diagnosis and treatment planning typically requires multiple images and, consequently, multiple doses of radiation. Beyond CBCT, beginning each comprehensive exam with a digital intraoral scan not only provides additional diagnostic information but also creates a record of the complete visible condition of the dentition. Furthermore, advanced diagnostic techniques such as the use of caries detection technology permit even earlier detection and complement traditional methods to give clinicians the most complete diagnostic picture.

Although sharp explorers and radiographs have been the primary means of caries detection for many years, both have limitations. The lesion has to become deep or large enough to be "seen" by the tip of the explorer or appear on a radiograph. Typically, by the time a lesion, especially an interproximal one, is visible on a radiograph, it has advanced so far that it requires restorative intervention.^3,4

Once caries has been diagnosed, a decision must be made whether or not to intervene restoratively. Restorative treatment thresholds have traditionally been based on radiographic lesion depth and clinical experience and vary among dentists. The decision to restoratively intervene in the caries process is also based upon a patient's caries risk.⁴

The use of caries detecting technology allows practitioners to diagnose earlier stages of decay, gives them more information about the progression of the caries, and allows them to treat caries more conservatively using remineralizing treatments, minimal preparation with fissurotomy burs, resin infiltration techniques, or other conservative options.

According to recent research, a majority of dentists would restore lesions that are confined to enamel and reaching the outer half of the dentin, irrespective of the surface involved. With regard to the occlusal surface, the percentage of dentists who restored enamel lesions ranged from 4.6% to 17.8%. Regarding dentin lesions, 50.2% to 70.2% of the dentists opted for invasive treatment. For approximal surfaces, the choice of invasive treatment for enamel lesions ranged from 5% to 88%. In lesions in the outer half of the dentin, 4.4% to 94% of dentists chose to restore.^5,6

During a routine examination, a patient's upper right quadrant was assessed for decay (Figure 1). Although the first and second molars exhibited some brown staining in the pits, the explorer failed to stick during probing. Visually, the brown staining could be diagnosed as arrested demineralization or simply as pit staining with no decay.

An image taken with a high-definition intra-oral camera (CamX^® Triton HD, Air Techniques) using a caries detection head (CamX^® Triton HD Spectra, Air Techniques) revealed incip-ient enamel caries, which appear blue, and deep enamel caries, which appear red (Figure 2). This caries detection device emits violet light that measures the reflective differences between healthy tooth structure and demineralized tooth structure. The stage of caries progression is analyzed and represented by color and number, while the healthy enamel displays as green. This florescence technology provides a means for diagnosing a range of lesions-from early demineralization to deep decay in pits, fissures, and on smooth surfaces-and calibrating them by number. This is more information than a simple visual examination can provide.

Next, an interproximal caries detection head (CamX^® Triton HD Proxi, Air Techniques) was used to look for any interproximal caries (Figure 3). No interproximal decay can be seen in the image, and the enamel appears clear and ice-like. This head detects caries interproximally without ionizing radiation by emitting an infrared light beam. Carious lesions absorb infrared light, whereas healthy tooth structure reflects the infrared light and appears transparent.

Using these caries detection heads allowed the clinician to assess all surfaces of the tooth and the depth of any lesions without subjecting the patient to radiation. Because of the deep enamel decay that was discovered, the decision was made to place conservative restorations with minimal preparation. The caries was removed and the lesions were prepared with a fissurotomy bur (Figure 4). After preparation, the teeth were selectively etched with 37% phosphoric acid for 15 seconds (Figure 5), and then the phosphoric acid was rinsed away. Next, a universal dental adhesive (All-Bond Universal^®, Bisco) was scrubbed into the preparations for 30 seconds (Figure 6). After the solvent was lightly air-dried away, a  highly esthetic bioactive composite (ACTIVA^™ BioACTIVE-RESTORATIVE^™, Pulpdent) was placed as the restorative material (Figure 7 and Figure 8).

Utilizing caries-detection technology, dentists can diagnose demineralization at earlier stages, saving their patients from more invasive restorative procedures and preserving their natural dentition. This is a big departure from traditional dental practice. Patients love this technology because they don't have to undergo as many x-ray images, and many are very receptive to accepting early treatment options, even if these treatments are paid for out of pocket. Patients also see this technology as a differentiation from traditional dental practices and are likely to talk about it with others, which can result in growth for the dental practices that offer it.

Susan McMahon, DMD
Fellow
International Academy of Dental-Facial Esthetics
Private Practice
Pittsburgh, Pennsylvania