Can red fluorescence be useful in diagnostic decision making of residual dentin caries?

A diagnosis based on traditional methods can differ under the same tooth condition. Additional diagnostic tools are required to overcome this limitation. QLF technology is a viable method for detecting residual caries and is increasingly being used to detect dentin-level residual caries. In this study we used the Qraypen (AIOBIO, Seoul, Korea) to investigate the usefulness of the QLF technology for diagnosing controversial cases. CASE 1: A 31-year-old man presented with pain in the left mandibular first molar. The old restoration and severe dental caries were removed as much as possible using traditional visual and tactile senses. The area of treatment was photographed using the Qraypen. We concluded that endodontic treatment was preferable based on the Qraypen findings combined with diagnostic information. CASE 2: A 67-year-old man presented with discomfort in the first molar on the right mandible. Most of the existing restoration and carious debris were removed. Black discoloration was observed around and within the crack line, but with no red fluorescence. Based on the results of these examinations we decided that a minimally invasive dentistry approach was appropriate.

Using QLF technology is more objective and accurate than other methods of determining the removal end point and detecting healthy marginal dentin for successful restoration.