What wavelength does the Diagnodent laser operate at for caries detection?

The Diagnodent laser operates at a wavelength of 655 nm, which falls within the red part of the visible spectrum. This specific wavelength is effective for detecting caries due to its ability to be absorbed by the dental tissues, particularly the carious enamel and dentin. The laser light interacts with the fluorescence emitted by the bacteria in decayed areas, making it possible to identify early stages of carious lesions that may not be visible during traditional examinations.

This wavelength effectively strikes a balance between penetration into the tooth structure and enhanced fluorescence signal from carious tissues, which is crucial for accurate detection. The other wavelengths listed either do not produce the necessary penetrating power or fluorescence response for effective caries detection, rendering them less suitable for this specific application in dental diagnostics.