Treatment equipment and performance A class IV low level laser (LiteCure LCT-1000®) and a similar sham laser will be used. Both devices are delivered by LiteCure, LLC, Newark, DE, USA. The active device delivers its energy by two wavelengths, 20% of the beam with 810 nm (nanometer) and 80% of the beam with 980 nm. Energy given will be tested before the start of the study and once every month, using Thor labs power meter PM100D and the photo sensor S 121 C, to make sure the device works correctly. There is also a red aiming beam with a wavelength of 650 nm and a power of 5 mW (milliwatt). The sham laser delivers solely the aiming beam.