LED Light Therapy Bed or Focused Laser?
Beyond Red Light TherapyThe First Law of Photodynamics states that light must be absorbed to be effective. For light to be absorbed it must have the right level of intensity at the skin. This intensity is called irradiance. Irradiance over time is a common measure of the Photobiomodulation dose, which we calculate in Joules. Think of a joule like 10 milligrams of aspirin.
Lasers produce coherent or highly focused light. Lasers can cut and burn and they can penetrate deep into cells to help reduce pain in joints. Cold Lasers are noninvasive lasers that might be better used to penetrate deep into a joint and reduce pain in that joint.
LED Light Therapy Beds produce incoherent or scattered light in very intense yet specific light therapy energy (wavelengths). An LED Light Therapy Bed can be intense enough to penetrate 2 – 4 cm into the body and be absorbed by the tissues, organs and systems of the body creating systemic change.
In addition, LED Light Therapy Beds deliver the correct dose of energy because the distance is relatively precise with an adjustable canopy. On the bench, we know exactly how far the LEDs are from the skin. On an adjustable canopy we can pull the lights closer to a thin body and leave them open for a thicker body. So while lasers provide coherent focused energy, LED therapy Beds produced relatively accurate dose-specific and multi-wave energy in coherent light.
Infrared light penetrates farthest (depper tissues, organs, and bone), Red’s penetrate the skin (dermal layer and wound healing) and green and blue are more intense energies that have lower levels of penetration yet may affect surface and wound healing more positively.
Studies have shown that LASERS and LED’s can have similar effects depending on the intensity. Lasers are much more effective for invasive procedures designed to cut or burn and they can be more effective in relieving deeper joint pain. LED’s are non-invasive (do not cut or burn) but researchers suggest that the right dose can have similar pain-relieving benefits with the addition of systemic benefits.
LED Light Therapy Beds may affect the entire body by reducing inflammation, improving cellular detoxification and circulation of nutrients. This broad root cause benefit of light therapy can affect nearly every tissue organ and system in the body. You just get better!
LED/Non-Coherent Light vs Lasers Clinical Trial Comparisons
LED Light Therapy Beds are a source of systemic photobiomodulation for the entire body. LED Light Therapy stimulates the flow of energy into the entire body. Lasers pinpoint focused energy (coherent) into a joint if spot. The chart below suggests the benefits from a full body photobiomodulation bed can be very similar to the benefits from laser treatment. Light heals.
| Study | Methodology | Indication | LED/non-coherent | LASER parameters | Results |
| Panhoca (2015) [107] | Comparison trial, uncontrolled | Temporomandibular disorder | 630 and 850; 150 mW; 300 mW/cm2; 18 J/cm2; 9 J/point | 780 nm; 70 mW; 1700 mW/cm2; 105 J/cm2; 4.2 J/point | There were no significant differences in pain scores and maximum oral aperture between groups at baseline or any periods after treatment. |
|---|---|---|---|---|---|
| Freitas (2014) [108] | Comparison trial, uncontrolled | Oral mucositis | 630 nm; 80mW; 0.24 J/point; 1 cm2 | 660 nm; 40 mW; 6.6 J/cm2; 0.24 J/point; 0.036 cm2 | LED and laser both were effective in alleviating oral mucositis scores, but LED had more pronounced effects. |
| Ammar (2014) [109] | Comparison trial, uncontrolled | Knee osteoarthritis | 890 nm; 62.4 J/cm2; 180 cm2 | 850 nm; 100 mW; 0.76 mm2 | LED and laser both appeared to be similarly effective in reducing pain and increasing physical function. |
| Esper (2011) [110] | RCT | Orthodontic pain | 640 nm; 100 mW; 4 J/cm2; 70 s | 660 nm; 30 mW; 4 J/cm2; 25 s | LED was effective in reducing orthodontic pain while laser was not. Laser dose (radiant energy) might have been too small. |
| Lizarelli (2010) [111] | RCT, double-blind | Dentin hypersensitivity | 630 nm; 25 mW; 5.4 J/cm2; 4 mm2 | 660 nm; 25 mW; 5.4 J/cm2; 4 mm2 | LED and laser were equally effective in the treatment of dentin hypersensitivity. |
| Lima (2016) [112] | RCT, double-blind | Pain after surgery | 640 nm; 70 mW; 10.1 J; 6 J/cm2; 1.77 cm2; 1216 s [Note: Wavelength reported in abstract contradicts with the wavelength provided in the full text.] | 660 nm; 40 mW; 2.4 J; 6 J/cm2; 0.4 cm2; 480 s [Note: Wavelength reported in abstract contradicts with the wavelength provided in the full text.] | LED and laser both were effective in decreasing pain on the 6th and 8th postoperative day. |
| Leal Junior (2009) [113] | RCT, double-blind, crossover | Exercise physiology | 660 + 850 nm; 34 red diodes and 35 near-infrared diodes; 1390 mW; 83.4 J; 6.0 J/cm2; 60 s | 810 nm; 1 laser diode; 200 mW; 12 J; 164.84 J/cm2; 60 s | LED decreased post-exercise creatine kinase, but neither LED or laser had effects on exercise performance or blood lactate levels. |
| Lima (2017) [114] | RCT, double-blind | Sternotomy healing | 640 nm; 70 mW; 10.1 J; 6 J/cm2; 1.77 cm2; 1216 s [Note: Wavelength reported in abstract contradicts with the wavelength provided in the full text.] | 660 nm; 40 mW; 2.4 J; 6 J/cm2; 0.4 cm2; 480 s [Note: Wavelength reported in abstract contradicts with the wavelength provided in the full text.] | LED and laser both were effective in decreasing hyperemia and incision bleeding or dehiscence. |
Source: “Photobiomodulation: lasers vs. light emitting diodes?” (Table 6) by Vladimir Heiskanen and Michael R. Hamblin
