Alessandro L. B. Vieira

Effects of low-level laser therapy on malignant cells: in vitro study.

The aim of this study was to assess the effect of 635- and 670-nm laser irradiation on H.Ep.2 cells in vitro using MTT. In addition to our previous report on the effects of LLLT on the proliferation of laryngeal carcinoma cells in which it was found that irradiaton H.Ep.2 cells with 670-nm laser results in increased cell proliferation, it was decided to evaluate the effect of increased doses of laser light on these cells. The cells, obtained from SCC of the larynx, were routinely processed from defrost to the experimental condition. The cultures were kept either at 5% or 10% of FBS. Twenty-four hours after transplantation, the cells were irradiated with laser light (5-mW diode lasers; 635 and 670-nm; beam cross section approximately 1 mm) at local light doses between 0.04 and 4.8.10(4) Jm(-2). For 670 nm, significant differences in the proliferation were observed between the two concentrations of FBS (p = 0.002) and between irradiated cultures and controls (p = 0.000). Although the results were not significant, 635-nm irradiated cells also proliferated more than nonirradiated ones. This occurred under both conditions of nutrition. It is concluded, that irradiation with 670-nm laser light applied at doses between 0.04 and 4.810(4) Jm(-2) could significantly increase proliferation of laryngeal cancer cells.

Does LLLT stimulate laryngeal carcinoma cells? An "in vitro" study

Low level laser therapy (LLLT) has been used successfully in biomedicine and some of the results are thought to be related to cell proliferation. The effects of LLLT on cell proliferation is debatable because studies have found both an increase and a decrease in proliferation of cell cultures. Cell culture is an excellent method to assess both effects and dose of treatment. The aim of this study was to assess the effect of 635nm and 670 nm laser irradiation of H.Ep.2 cells in vitro using MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide). The cells were obtained from squamous cell carcinoma (SCC) of the larynx and were routinely processed from defrost to the experimental condition. Twenty-four hours after transplantation the cells were irradiated with doses ranging from 0.04 to 0.48J/cm2 for seven consecutive days (5 mW diode lasers: 635nm or 670 nm, beam cross-section approximately 1 mm) at local light doses between 0.04 and 0.48 J/cm2. The results showed that 635nm laser light did not significantly stimulate the proliferation of H.Ep.2 cells at doses of 0.04 J/cm2 to 0.48 J/cm2, However, 670nm laser irradiation led to an increased cell proliferation when compared to both control and 635nm irradiated cells. The best cell proliferation was found with 670nm laser irradiated cultures exposed to doses of doses of 0.04 to 0.48 J/cm2. We conclude that both dose and wavelength are factors that may affect cell proliferation of H.Ep.2 cells.

Effects of LLLT on malignant cells: study in vitro

In addition to our previous report on the effects of LLLT on the proliferation of laryngeal carcinoma cells in which it was found that irradiation H.Ep.2 cells with 670nm laser results in increased cell proliferation, ti was decided to evaluate the effect of increased does of laser light. The aim of this study was to assess the effect off 635 and 670 nm laser irradiation of H.Ep.2 cells in vitro using MTT. The cells, obtained from SCC of the larynx, were routinely processed from defrost to the experimental condition. The cultures were kept either at 5 or 10 percent of FBS. Twenty- four hours after transplantation, the cells were irradiated with laser light at local light doses between 0.04 and 4.8 X 104 Jm-2. For 670 nm, significant differences in the proliferation were observed between the two concentrations of FBS and between irradiated cultures and controls. Although the results were not significant, 635 nm irradiated cells also proliferated more than non- irradiated ones. This occurred under both conditions of nutrition. It is concluded, that irradiation with 670 nm laser light applied at doses between 0.04 and 4.8 X 104 Jm-2 could significantly increase proliferation of laryngeal cancer cells.

Is LLLT effective in the management of TMJ pain

The authors report on the effects of LLLT in the treatment of TMJ pain. This paper reports the results of the use of LLLT on the treatment of TMJ pain and presents LLLT as an effective method of treating such problem. One hundred forty six female and 24 male patients aged between 7 and 81 years old (average 38.6 years old) suffering TMJ pain were treated with 632.8, 670, and 830 nm diodes Lasers at the Laser Center of the UFPE. The treatment consisted of a series of 12 applications twice a week. Patients were treated with an average dose of 2.4 J/cm2. One hundred twenty eight out of 180 patients were asymptomatic at the end of the treatment, 26 improved considerably and 26 were symptomatic. These results show although LLLT does not cure TMJ disorders it is effective in reducing TMJ pain.

Effects of LLLT on the proliferation of HEp2 cells: study in vitro

LLLT has been used successfully in biomedicine and some of the results are thought to be related to cell proliferation. The effects of LLLT on cell proliferation is debatable because different studies found either increase or decrease on proliferation of cell cultures. Cell culture is an excellent method to assess both effects and dose of treatment. The aim of this study was to assess the effect off 635 and 670 nm laser irradiation of H.Ep.2 cells In Vitro using MTT. The cells were obtained from SCC of the larynx were routinely processed from defrost to the experimental condition. Twenty four hours after transplantation the cells were irradiated with doses ranging from 0.03 a 0.6 J/cm2 during seven days. The results showed that 635 nm laser light does not stimulate significantly the proliferation of H.Ep.2 cells in doses ranging from 0.04J/cm2 to 0.488J/cm2. However 670 nm laser irradiation resulted in an increased cell proliferation when compared to both control and 635 nm irradiated cells. It is concluded that irradiation of H.Ep.2 cells with 670 nm laser results in an increased cell proliferation; best observation of cell proliferation was found on 670 nm laser irradiated cultures exposed from doses of 0.075 J/cm2; both dose and wavelengths are factors which may affect cell proliferation of H.Ep.2 cells; doses of 635 nm laser light up to 0.48J/cm2 did not interfere with H.Ep.2 cell proliferation; and that the MTT was effective on the detection of H.Ep.2 cells proliferation on both irradiated and non-irradiated cell cultures.

Effects of 635- and 670-nm laser irradiation on Candida albicans: study in vitro

This study aimed to assess the effect of the use of lasers (635; 670nm) on Candida albicans In Vitro. Cultures of microorganisms were irradiated with and without artificial illumination and non-irradiated cultures acted as controls. A single irradiation with the dose of 1.5J/cm2 was used and measurements of DO and NC assessed the effects of the irradiation. The measurements were carried out with 24 (T1), 48 (T2) and 72 (T3)after irradiation. The results showed a significant difference between groups with relation to the DO on the presence of illumination. There are significant differences between the three groups at T1 and T3 related to the NC. In all situations significant differences were observed highest values occurred when illumination was not used. Cultures irradiated with the laser 635 nm grow faster than those irradiated with the laser 670 nm. Measurements of DO/NC were sensitive to detect changes in Candida albicans cultures irradiated or not. It is concluded that a single irradiation of Candida albicans cultures with laser of 670 and 635 nm results in proliferation of the microorganisms In Vitro.

Nonsurgical laser treatment (NSLT) in the management of disorders of the maxillofacial region

The authors report on the effects of NSLT in the treatment of maxillofacial disorders. Further to our previous study, this paper reports the results of the use of NSLT on the treatment of several disorders of the oral and maxillofacial region. This paper presents NSLT as an effective method of treating such disorders. Two hundred and five female and 36 male patients aged between 7 and 81 years old (average 38.9 years old) suffering from disorders of the maxillofacial region were treated with 632,8,670, and 830nm diodes Lasers at the Laser Center of the Universidade Federal de Pernambuco (UFPE). The disorders included TMJ pain, Trigeminal neuralgia, muscular pain, aphatae, inflammation, tooth hypersensitivity, postoperatively, and in small haemangiomas. Most treatment consisted of a series of 12 applications (twice a week) and in 15 cases a second series was applied. Patients were treated with an average dose of 1.8 J/cm2. One hundred fifty four out of 241 patients were asymptomatic at the end of the treatment, 50 improved considerably and 37 were symptomatic. These results confirm that NSLT is an effective tool and brings many benefits for the treatment of many disorders of the Maxillofacial region.