Laser biostimulation of cartilage: in vitro evaluation

An in vitro study was performed to evaluate the laser biostimulation effect on cartilage using a new gallium-aluminium-arsenic diode laser. Chondrocyt e cultures were derived from rabbit and human cartilage. These cells were e xposed to laser treatment for 5 days, using the following parameters: 300 j oules, 1 watt, 100 (treatment A) or 300 (treatment B) hertz, pulsating emis sion for 10 minutes, under a sterile laminar flow. Control cultures (no tre atment) received the same treatment with the laser device off. Cell viabili ty was measured by MTT assay at the end of the laser treatment and then aft er 5 days. Neither rabbit nor human cultured chondrocytes showed any damage under a light microscope and immunostaining control following laser treatm ent. The MTT test results indicated a positive biostimulation effect on cel l proliferation with respect to the control group. The increase in viabilit y of irradiated chondrocytes was maintained for five days following the end of the laser treatment. The results obtained with the Ga-Al-As diode laser using the above tested parameters for in vitro biostimulation of cartilage tissues provide a basis for a rational approach to the experimental and cl inical use of this device. (C) 2001 Editions scientifiques et medicales Els evier SAS.