Onychomycosis is a worldwide problem with no tendency for self-healing, and existing systemic treatments achieve disease-free nails in only 35 to 76% of cases. Recently, treatment of
nail fungus with a near-infrared
laser has been introduced. It is assumed that fungal eradication is mediated by local heat. To investigate if
laser treatment has the potential to eradicate fungal hyphae and arthrospores,
laser heat application and propagation needs to be studied in detail. This study aimed to measure nail temperatures using real-time videothermography during
laser irradiation. Treatment was performed using 808- and 980-nm linear scanning
diode lasers developed for
hair removal, enabling contact-free homogeneous irradiation of a human nail plate in one pass. Average and peak temperatures increased pass by pass, while the
laser beam moved along the nail plates. The achieved mean peak temperatures (808 nm: 74.1 to 112.4°C, 980 nm: 45.8 to 53.5°C), as well as the elevation of average temperatures (808 nm: 29.5 to 38.2°C, 980 nm: 27.1 to 32.6°C) were associated with
pain that was equivalent to that of
hair removal procedures and was not significantly different for various wavelengths. The linear scanning
laser devices provide the benefits of contact-free homogeneous heating of the human nail while ensuring adequate temperature rises.