LLLT

Low-level laser therapy (LLLT), also known as low-level light therapy, is a form of photobiomodulation that uses low-intensity lasers or light-emitting diodes to stimulate cellular function and tissue repair. It is distinguished from higher-power surgical lasers by the low power output and non-ablative approach.

The proposed mechanism involves photons being absorbed by mitochondrial chromophores, particularly cytochrome c oxidase. This absorption can increase adenosine triphosphate (ATP) production, modulate reactive oxygen species, and trigger nitric oxide release. These changes may influence cellular signaling, gene expression, inflammation, and tissue repair, potentially enhancing healing and reducing pain in certain conditions. Wavelengths used typically span roughly 600 to 1000 nanometers, with both continuous and pulsed modes employed.

Clinical use covers a range of indications. It is commonly applied for musculoskeletal pain and inflammation, including neck pain, shoulder tendinopathy, and osteoarthritis, as well as to promote wound healing and to manage mucositis in cancer therapy. Cosmetic and dermatologic applications include hair growth stimulation and skin rejuvenation. In dentistry, LLLT is used for pain relief and wound healing after procedures. The evidence base is mixed: some systematic reviews report small to moderate benefits for specific conditions, while others find results inconclusive due to variability in devices, doses, treatment parameters, and study design.

Safety and guidelines emphasize protective eyewear for operators and patients during laser use. LLLT is generally well tolerated with rare adverse effects, typically mild and transient. Proper dosing and device-specific protocols are important, as effectiveness is highly dependent on wavelength, dose, and timing.