A study was carried out to observe the acceleration of wound healing using different wavelengths of laser, and to assess the role played by the amount of laser transmitted by the skin during wound healing in rats. An oval full thickness skin wound was created aseptically with a scalpel on the shaved back of the two groups of rats, control and treatment groups. Treatment was carried out with HeCd, Argon, HeNe, Krypton and GaAlas lasers, at doses of 10, 20, and 30 J/cm² with a treatment schedule of 3 times per week. Our results show that the rate of wound healing acceleration in days (AccD) were 15.09%, 22.93%, 29.24%, 14.54%, 23.21% and 20.37% using optimum stimulation dose of 20 J/cm² and wavelengths of 442 nm, 488-514 nm, 632 nm, 670 nm, 780 nm and 830 nm. The results suggest that HeNe laser with 632nm was the most effective in promoting wound healing when compared to other wavelengths used in this study. The measurement of laser skin transmission indicated that this would rise correspondingly as the wavelength of the laser in the spectral range of 442 nm to 830 nm. The results suggest that laser skin transmission is not proportionate to the amount of laser biostimulation. The acceleration of wound healing may not be attributed to skin transmission.

View full abstract

Temporomandibular joint (TMJ) pain can be very debilitating for the affected patient, particularly when it is a chronic disorder associated with temporomandibular disorder (TMD). Low reactive laser therapy (LLLT) has been proved effective in a variety of pain etiologies, and low incident levels of diode laser irradiation are very effective in relieving TMJ joint pain associated with TMD, as the first stage in a two-staged strategy in the successful treatment of TMD. The present study reports on four representative cases of TMJ pain treated with a GaAlAs diode laser, 830 nm. continuous wave, 150 mW for 5 to 10 sec/point, once per week. Incident energy densities were from approximately 20 J/cm² to 40 J/cm². One of the possible pain relief mechanisms involves the LLLT-mediated improved microcirculation in the temporal and masseter muscles, thereby relaxing and softening the affected muscles and relieving the pain. This also helps with cases of trismus. LLLT is side-effect free, is easy to apply and is well-tolerated by all ages and conditions of patient. When used in combination with conventional orthodontic maneuvers to remedy the functional defects behind the TMD, LLLT offers the practitioner a safe and effective method for pain relief in troublesome TMJ pain patients.

View full abstract

Apoptosis is a physiological process of cell death. Activation of macrophages by lipopolysaccharides delays macrophage apoptosis. However, the extended life of macrophages further stimulates inflammation and results in local tissue damage. Exposure to low level lasers is also known to activate mononuclear phagocytes. Therefore, we determined if monocytes exposed to low level lasers (He-Ne & Nitrogen lasers) exhibit delayed apoptosis. Monocytes from 5 healthy volunteers were isolated from peripheral blood and cultured in microwells in-vitro. Replicate wells containing macrophages were exposed to He-Ne and Nitrogen lasers thrice on alternate days and the percentage of apoptotic cells were counted after staining with acridine orange stain. Apoptosis was observed in 0.52 to 12 % of the non-irradiated control cells, compared with 22 to 99 % of cells exposed to Nitrogen laser. He-Ne laser exposed cells showed a greater percentage of apoptotic cells than controls, but less so than Nitrogen laser exposed cells. The present observations revealed increased apoptotic death rates for monocytes exposed to He-Ne and Nitrogen lasers, suggesting that both lasers may reduce inflammation in diseases such as tuberculosis.

View full abstract

Twenty patients with lower limb arteriosclerosis were treated with a 20mW continuous wave He-Ne laser (632nm) and a 250 mW continuous diode laser (830 nm), simultaneously. The laser light was applied to the lumbar paravertebral region transcutaneously for 30 minutes 6 days per week for 2 months, using a scanner. The treatment yielded an 87.2% success rate in reducing the deleterious effects of lower limb arteriosclerosis, a condition that is generally difficult treat.

View full abstract

GaAlAs 820nm diode laser system (Biotherapy 2001 Laser Unit, manufactured by OMEGA Laser Systems Ltd, London, U.K.) was used for the postoperative treatment of onychomycotic nails. Traditional treatment of onychomycosis has consisted of mechanical debridement of the affected nails accompanied by topical antifungal medication, systemic antifungal medications, or surgical removal and matrixectomy. The aim of this study was to evaluate the method of surgical avulsion using a CO₂ laser (7W, 0.1mm) and a new protocol of low level laser therapy infrared diode laser GaAlAs (820nm, 100mW, 4J cm²) was applied for two weeks at three day intervals to improve the recurrence rate, pain score and healing time. Sixty patients were assigned to three groups (A, B and C). ANOVA statistical tests showed that there was a significant difference between the group A, B and B,C (P<0.005) in the measured mean healing time and pain score, but no statistical difference between group A and C (P<0.01). It was concluded that low level laser therapy reduced pain, improved the healing time and resulted in a lower recurrence rate.

View full abstract

Certain crystals cause synovial tissue inflammation and variability of inflammatory indicators like plasmatic prostaglandin E₂ (PGE₂), fibrinogen (PF) and synovial tissue PGE₂. We evaluated Helium-Neon Laser efficacy on PF, plasmatic PGE₂ and synovial PGE₂ and its ability to induce involution of anatomopathological (AP) lesions in induced granulomatose process, alone and combined with a meloxicam injection. Rats were assigned to five different treatment groups. 5 mW He-Ne Laser radiation (632.8 nm) and 8 J.cm² energy density were used in the treated groups. PF and plasmatic PGE₂ and synovial PGE₂ levels decreased in granulomatose arthritis groups treated with low level laser therapy (LLLT) or with a meloxicam injection or a combination of both therapies; the differences being statistically significant (p<0.01), as compared with the non-treated control group. In the combination therapy group, involution of granulomatose inflammation was observed. We conclude that He-Ne laser treatment or meloxicam administration after experimentally induced inflammation, normalizes plasmatic PGE₂ and fibrinogen levels, but produces similar histological lesions as non-treated controls.

View full abstract