Most therapeutic lasers are classified by the Food and Drug Administration as Class III lasers, which are known as low-level laser therapy (LLLT), cold laser therapy and low-power laser therapy because they are restricted to intensities that can only induce minimal (if any) temperature elevation (not more than 0.1-0.5° C). This limits the amount of energy delivered and laser power to 500 mW or less. While they do seem an effective way to produce analgesia and accelerate healing of a variety of clinical conditions, they are not as powerful or effective as higher powered lasers.
The FDA has cleared Class IV therapeutic lasers (not to be confused with Class IV surgical lasers, which cut and cauterize tissue.) which are differentiated from Class III Lasers based on much greater power, offer faster results, deeper penetration, and a larger surface treatment area.
Class IV lasers may offer better therapeutic outcome, based on six characteristics of this new technology:
Class IV laser therapy has demonstrated the ability to significantly accelerate and enhance the body’s natural defense and repair components in the presence of injury, inflammation and certain disease processes through the action of photo-stimulation of light reactive biological receptors (chromophores) in the body. Laser therapy is consistent in providing pain relief, reducing injury damage and loss of function by modifying the effects and limiting the duration of inflammation, as well as enhancing specific repair and healing processes, and facilitating more rapid repair and producing stronger healed tissue structures. Multiple clinical studies have noted the following results of Laser therapy:
Lasers work when light receptive chromophores are irradiated with coherent laser light. The transferred energy stimulates increased action in cellular and sub-cellular tissues. Penetrating much deeper than other incoherent light wave forms, laser light activates increased mitochondrial ATP synthesis, mitigates mast cell inflammation and increases Ca++ ion presence and beneficial reactive oxygen species (ROS) production. Through the action of photo bio-stimulation, oxidative metabolism is increased via cytochrome C oxidaseand photosensitization of hemoglobin. Laser irradiation stimulates increased endorphin release and increased prostaglandin synthesis. Photon-stimulation leads to both localized and systemic reactions that result in immunomodulation and reduction of inflammation. Damaged skeletal, connective and neurological tissues and structures react with enhanced healing with lasers.