Research On The Effects Of 630nm/808nm Double-wavelength Laser In Wound Healing And The Key Technologies Of The Instrument

The wound has been one of the main causes of human disability and death, especially some chronic ones which always last for a long term, such as severe burn, bedsore, etc. It brings great suffering to the patients and causes millions of people dead each year in the world. People are still looking for new treatments that can speed up wound healing with less scars left.Low level laser therapy (LLLT) has been the new hope for wound healing because of its characteristics which are easy operation, painless, low toxicity, no contact with the wound surface, etc. During more than forty years' LLLT study for wound healing, the researchers had done a lot of experiments with different wavelengths and dosages. The results were inconsistent.To verify and explore the effect of different wavelengths of low level laser for wound healing, 32 wound model Wistar rats were randomly divided into A, B, C and D Group. Group A received no laser treatment. Group B received 5mW/cm~2 630nm red laser treatment. Group C received 10mW/cm~2 808nm IR laser treatment. Group B received a combination of both 5mW/cm~2 630nm red laser and 10mW/cm~2 808nm IR laser treatment. After the wound model caused, the treatment groups were exposed to laser irradiation for 10 minutes once a day. The treatment lasted for 14 days with 2 days rest after a 6 days' constantly irradiation. The wound area was recorded every two days. The pathologic changes of wound tissue were observed by HE staining section. The expression of TGF-β1 in the wound tissue was determined by the immuneohistochemical techniques. Statistical analysis revealed that both of the 630nm red laser treatment and the combination of both 630nm red laser and 808nm IR laser treatment could speed up wound shrinkage (p <0.05). But the 808nm IR laser treatment could not speed up wound shrinkage (p >0.05). The curative effect for wound healing was no statistical significance between the 630nm red laser treatment and the combination of both 630nm red laser and 808nm IR laser treatment (p >0.05). The change of expression area of TGF-β1 was statistical significance on different date (p <0.05). It increased firstly and then reduced. The effect of low level laser of different wavelengths for the TGF-β1 expression in wound tissue was not observed (p>0.05).This study proved that the 630nm red laser treatment and the combination of both 630nm red laser and 808nm IR laser treatment both could speed up wound healing obviously, and the curative effect is equivalence. The 808nm IR laser treatment could not speed up wound healing. TGF-β1 was expressed in the inflammatory exudation, the inflammatory cells, the fibroblast, the endodermis cells of capillary vessel, and the epithelia, etc. The expression increased firstly and then reduced. The effect of low level laser for the expression of TGF-β1 was not observed. Based on the experiment, this thesis studied the key technologies of the 630nm/808nm double-wavelength semiconductor laser instrument for the further research and clinical development.