Láser de baja frecuencia para aftas mayores recurrentes. Caso Clínico / Low frequency laser for major recurrent aphthous stomatitis. Clinical case

La estomatitis aftosa recurrente (menor, mayor o herpética) es una de las enfermedades bucodentales más frecuentes, de etiología multifactorial y con predisposición genética. Para esta patología su diagnóstico es clínico, y tomando como base la historia clínica se puede discriminar con otras patologías ulcerativas. La terapia con láser de baja potencia (LLLT) se propone como un tratamiento no invasivo, actuando como un fotomodulador celular, por lo que reduce el dolor, la inflamación, y estimula la regeneración tisular, previniendo daños. En el presente artículo se reporta a un niño de 11 años con una herida dolorosa de 4 meses en el borde posterior de la lengua que apareció tras una mordedura, en el que a la exploración clínica se encontró una lesión amarillenta con zonas enrojecidas, rodeada de un halo blanquecino de bordes redondeados. Para el tratamiento se utilizó LLLT, luego de una semana disminuyó el dolor, el paciente comenzó a comer correctamente, a los 15 días se observó una reducción de los bordes rojizos de la lesión, pasado el mes la lesión había remitido casi por completo. La LLLT se describe como un tratamiento eficaz, no invasivo, reduciendo los síntomas, y mejorando la calidad de vida del paciente al promover la curación de las lesiones.

Recurrent aphthous stomatitis (minor, major or herpetic) is one of the most frequent bucodental diseases, of multifactorial etiology and with genetic predisposition. The diagnosis of this pathology is clinical, and based on the clinical history it can be discriminated with other ulcerative pathologies. Low power laser therapy (LLLT) is proposed as a non-invasive treatment, acting as a cellular photo modulator, which reduces pain, inflammation, and stimulating tissue regeneration, preventing damage. This article reports an 11-year-old boy with a 4-month-old painful wound on the posterior edge of the tongue that appeared after a bite, in which clinical examination revealed a yellowish lesion with reddened areas, surrounded by a whitish halo with rounded edges. LLLT was used for the treatment, after one week the pain decreased, the patient started to eat properly, after 15 days a reduction of the reddish edges of the lesion was observed, after one month the lesion had almost completely remitted. LLLT is described as an effective, non-invasive treatment, which reduces symptoms and improves the patient's quality of life promoting the healing of the lesions.

Photobiomodulation therapy assisted orthodontic tooth movement: potential implications, challenges, and new perspectives / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Over the past decade, dramatic progress has been made in dental research areas involving laser therapy. The photobiomodulatory effect of laser light regulates the behavior of periodontal tissues and promotes damaged tissues to heal faster. Additionally, photobiomodulation therapy (PBMT), a non-invasive treatment, when applied in orthodontics, contributes to alleviating pain and reducing inflammation induced by orthodontic forces, along with improving tissue healing processes. Moreover, PBMT is attracting more attention as a possible approach to prevent the incidence of orthodontically induced inflammatory root resorption (OIIRR) during orthodontic treatment (OT) due to its capacity to modulate inflammatory, apoptotic, and anti-antioxidant responses. However, a systematic review revealed that PBMT has only a moderate grade of evidence-based effectiveness during orthodontic tooth movement (OTM) in relation to OIIRR, casting doubt on its beneficial effects. In PBMT-assisted orthodontics, delivering sufficient energy to the tooth root to achieve optimal stimulation is challenging due to the exponential attenuation of light penetration in periodontal tissues. The penetration of light to the root surface is another crucial unknown factor. Both the penetration depth and distribution of light in periodontal tissues are unknown. Thus, advanced approaches specific to orthodontic application of PBMT need to be established to overcome these limitations. This review explores possibilities for improving the application and effectiveness of PBMT during OTM. The aim was to investigate the current evidence related to the underlying mechanisms of action of PBMT on various periodontal tissues and cells, with a special focus on immunomodulatory effects during OTM.

Oxidative stress is involved in LLLT mechanism of action on skin healing in rats

The skin injury healing process involves the main phases of homoeostasis, inflammation, proliferation, and remodeling. The present study aimed to analyze the effects of low-level laser therapy (LLLT) on hematological dynamics, oxidative stress markers, and its relation with tissue healing following skin injury. Wistar rats were divided into control, sham, skin injury, and skin injury LLLT. The biochemical and morphological analyses were performed in the inflammatory (1 and 3 days) and regenerative phases (7, 14, and 21 days) following injury. The skin injury was performed in the dorsal region, between the intrascapular lines, using a surgical punch. LLLT (Al-Ga-In-P, λ=660 nm, energy density of 20 J/cm2, 30 mW power, and a time of 40 s) was applied at the area immediately after injury and on every following day according to the experimental subgroups. LLLT maintained hematocrit and hemoglobin levels until the 3rd day of treatment. Surprisingly, LLLT increased total leukocytes levels compared to control until the 3rd day. The effects of LLLT on mitochondrial activity were demonstrated by the significant increase in MTT levels in both inflammatory and regenerative phases (from the 1st to the 7th day), but only when associated with skin injury. The results indicated that LLLT modulated the inflammatory response intensity and accelerated skin tissue healing by a mechanism that involved oxidative damage reduction mostly at early stages of skin healing (inflammatory phase).

Clinical and experimental knowledge of photobiomodulation in accelerated orthodontics: A review / Conocimiento clínico y experimental de la fotobiomodulación en ortodoncia acelerada: Una revisión

Background: In recentyears, there has been an increasing interest in finding a noninvasive method to induce the accelerationofdentalmovement,methodssuchaslowintensityvibrations,pulsedelectromagneticfields,andlow-level laser therapy (LLLT). There have been multiple studies on the efficacy of LLLT in animal models, in vitro and in patients without conclusiveresults. Objective: Evaluate the state of the art on the use of LLLT to increase the rate of the orthodontic tooth movement to create a concise reference guide of the different laser and protocols available. Materials and Methods: The authors searched electronic databases (MedLine, Scopus and Semantic Scholar) for articles that evaluated the effectsoflow-leverlasertherapyontheorthodontictoothmovement.Screeningwasperformedatthetitle/abstract and full-text level. Data extraction and quality assessment were performed by two reviewers independently. The reference lists of relevant studies were also screened for further relevantliterature. Results: We found conflicting information as to the efficacy of LLLT to accelerate the orthodontic tooth movement (OTM). There is no consensus in the way the irradiation should be performed. Conclusions: The lack of a standardized irradiation protocol makes it hard to compare conflicting results, even in cases where the laser have the same technical specifications.

Antecedentes: En los últimos años, ha habido un interés creciente en encontrar un método no invasivo para inducir la aceleración del movimiento dental, métodos como vibraciones de baja intensidad, campos electromagnéticos pulsados y terapia con láser de bajo nivel(LLLT). Se han realizado múltiples estudios sobre la eficacia de la LLLT en modelos animales, in vitro y en pacientes sin resultados concluyentes. Objetivo: Evaluar el estado del arte en el uso de LLLT para aumentar la velocidad del movimiento dental ortodóncico para crear una guía de referencia concisa de los diferentes láser y protocolos disponibles. Materiales y métodos: Los autores buscaron en bases de datos electrónicas (MedLine, Scopus y Semantic Scholar) artículos que evaluaran los efectos de la terapia con láser de baja intensidad sobre el movimiento dental ortodóncico. La selección se realizó a nivel de título / resumen y texto completo. Dos revisores realizaron de forma independiente la extracción de datos y la evaluación de la calidad. También se examinaron las listas de referencias de estudios relevantes para obtener más literatura significativa. Resultados:EncontramosinformacióncontradictoriaencuantoalaeficaciadelaLLLTparaacelerarel movimiento dental ortodóncico (OTM).No hay consenso sobre la forma en que se debe realizar lairradiación. Conclusiones: La falta de un protocolo de irradiación estandarizado dificulta la comparación de resultados, incluso en los casos en que el láser tiene las mismas especificaciones técnicas.

Neovascularization: topical effects of streptococcus thermophilus and low level laser therapy in treatment of diabetic wound in rats

Background: Diabetic wound is a major socioeconomic debilitating problem in this society. Various treatment options are available but still it requires better treatment option. In diabetes mellitus the oxygenation to the tissues is reduced. In this study effects of low level laser therapy were compared with topical application of Streptococcus thermophilus on diabetic wounds that induces formation of new blood vessel and free radical scavenging system, a comparative study to get better treatment option for diabetic wounds.Methods: 18 male rats were selected and divided randomly into three groups. Diabetes was induced in all the rats by using the Alloxan monohydrate at a dose of 120mg/kg of the body weight. Group A was treated with normal saline, group B was treated with low level laser therapy and group C was treated with Streptococcus thermophilus topically. Skin tissues were collected on day three and seven, slides were prepared for microscopic examination to observe the new blood vessels formation.Results: Mean number of new blood vessel formation was observed in group B compared with group A and C. Significant vasculogenesis was seen in group B when treated with Low level laser therapy.Conclusions: In the group of low level laser therapy new blood vessel formation was seen with better wound healing. It means LLLT provides better oxygenation to the tissues by generation of new blood vessels compared with Streptococcus thermophilus and normal saline.

Aplicación del Láser de Baja Potencia (LLLT) en Pacientes Pediátricos: Revisión de Literatura a Propósito de una Serie de Casos / Application of Low Power Laser (LLLT) in Pediatric Patients: Review of the Literature in a Series of Cases

RESUMEN: El uso del láser de baja potencia en odontología está siendo cada vez más frecuente y con excelentes resultados, los equipos más modernos traen pre-establecidos la dosimetría de los parámetros para las diferentes acciones clínicas. El objetivo de esta revisión fue encontrar evidencia científica que permita al clínico tener como una alternativa de tratamiento el uso del láser de baja potencia en patologías orales de tejidos blandos y duros en pacientes pediátricos. Se realizó una revisión de la literatura por medio de buscadores como PubMed, LILACS y SciELO. Después de leer a texto completo todos los trabajos es posible señalar que el láser de baja frecuencia es una buena alternativa terapéutica en la resolución de signos y síntomas en patologías orales que aquejan al paciente pediátrico, puesto que, presenta un rápido control del dolor, la inflamación, el sangrado y acelera los procesos de reparación celular.

ABSTRACT: Low Level Laser Therapy in dentistry is becoming more frequent and has had excellent results, with state of the art equipment having pre-established dosimetry parameters for the various clinical actions. The objective of this review was to find scientific evidence that allows the clinician to have the use of low power laser as treatment alternative, in oral soft tissue and hard pathologies in pediatric patients. A review of the literature was performed through search engines such as PubMed, LILACS and SciELO. After reading the texts, it was possible to point out that low frequency laser is a good therapeutic alternative in the resolution of signs and symptoms in oral pathologies of the pediatric patient. This alternative allows for rapid pain control, reduces inflammation and bleeding, and accelerates cellular repair processes.

Lasers : A Ray Towards Periodontics

Theodore maiman in 1960 invented the ruby laser, since then lasers technology has holded the attention in dental practice and has revolutionised dental treatment. Lasers have been used in initial periodontal therapy, surgery, and also in implant treatment. Lasers have various periodontal applications including calculus removal; for removal of the pocket epithelium; soft tissue excision, incision and ablation; decontamination of root and implant surfaces; biostimulation; bacteria reduction; and osseous surgery. Further research is necessary on lasers so that it can become a part of the dental procedures. This paper gives an acuity to laser in Periodontics.

Low Level Light Therapy Using an 830-nm Light Emitting Diode Promotes Wound Healing via TGF-β/SMAD Pathway Activation / 대한피부과학회지

BACKGROUND: The transforming growth factor-β/SMAD (TGF-β/SMAD) pathway plays an important role in tissue repair and collagen synthesis. Low-level light therapy (LLLT) is increasingly used to alleviate pain and inflammation and promote wound healing. However, few studies have directly compared the effects of different wavelengths of light-emitting diodes (LEDs) or examined their individual effects at the molecular level. OBJECTIVE: Here we used a mouse model to investigate the effect of blue (410 nm), red (630 nm), and infrared (830 nm) LEDs on wound closure and assessed the underlying changes in a signal transduction pathway. METHODS: A full-thickness wound was created on the dorsal skin of mice using a 6-mm-diameter punch. In part I, the wounds were irradiated using blue, red, and infrared LEDs. In part II, the wounds were irradiated at different time points. Photo documentation, serial skin biopsies, wound measurements, and immunohistochemical staining using TGF-β/SMAD pathway-related molecules were performed. RESULTS: The overall wound closure percentage was highest during the first 10 days when an 830-nm LED was used. The wound closure process was accelerated when the irradiation was initiated immediately after wounding. Irradiation using 830-nm LED upregulated TGF-β and collagen-1 but downregulated SMAD7. CONCLUSION: Our findings show that LLLT using an 830-nm wavelength LED delivered immediately after wound formation may have the best effect on wound healing by upregulating the TGF-β/SMAD signaling pathway.

Effect of low-level laser therapy on bisphosphonate-treated osteoblasts / 대한악안면성형재건외과학회지

BACKGROUND: This study investigates the effect of alendronate-treated osteoblasts, as well as the effect of low-level laser therapy (LLLT) on the alendronate-treated osteoblasts. Bisphosphonate decreases the osteoblastic activity. Various treatment modalities are used to enhance the bisphosphonate-treated osteoblasts; however, there were no cell culture studies conducted using a low-level laser. METHODS: Human fetal osteoblastic (hFOB 1.19) cells were treated with 50 μM alendronate. Then, they were irradiated with a 1.2 J/cm² low-level Ga-Al-As laser (λ = 808 ± 3 nm, 80 mW, and 80 mA; spot size, 1 cm²; NDLux, Seoul, Korea). The cell survivability was measured with the MTT assay. The three cytokines of osteoblasts, receptor activator of nuclear factor κB ligand (RANKL), osteoprotegerin (OPG), and macrophage colony-stimulating factor (M-CSF) were analyzed. RESULTS: In the cells treated with alendronate at concentrations of 50 μM and higher, cell survivability significantly decreased after 48 h (p < 0.05). After the applications of low-level laser on alendronate-treated cells, cell survivability significantly increased at 72 h (p < 0.05). The expressions of OPG, RANKL, and M-CSF have decreased via the alendronate. The RANKL and M-CSF expressions have increased, but the OPG was not significantly affected by the LLLT. CONCLUSIONS: The LLLT does not affect the OPG expression in the hFOB cell line, but it may increase the RANKL and M-CSF expressions, thereby resulting in positive effects on osteoclastogenesis and bone remodeling.

Clinical efficacy of low level laser therapy in reducing pain and swelling after periapical surgery: a preliminary report / Eficacia clínica de láser terapéutico de bajo nivel de emisión en la reducción de dolor e inflamación posterior a cirugía periapical: reporte preliminar

The objective of this study was to evaluate the efficacy of the low level laser therapy (LLLT) in postoperative pain and swelling associated with periapical surgery. A double-blind, randomized, controlled clinical trial was carried out in 2 groups of 10 patients each, undergoing periapical surgery. The experimental group was treated with an intraoral application of an 810 nm-GaAsAl-laser, having an output power of 100 mW, with overlapping movements over the wound. In the control group, the same procedure was carried out, without therapeutic laser activation. Postoperative pain, swelling, and rescue medication were registered. The experimental group exhibited a decrease in pain intensity after periapical surgery compared with control group (p<0.05). There was not significant statistical difference between the groups in terms of swelling. Six patients of the control group required rescue medication. The use of LLLT in the postoperative management of patients having periapical surgery, using the protocol of this study reduced postoperative pain...

El objetivo del estudio fue evaluar la eficacia del láser terapéutico de bajo nivel de emisión (LTBNE) en el dolor postoperatorio e inflamación asociados con cirugía periapical. Se realizó un ensayo clínico controlado aleatorizado doble ciego en 2 grupos de 10 pacientes cada uno, que requirieron de cirugía periapical. El grupo experimentalfue tratado con una aplicación intraoral de laser de GaAsAl de 810 nm, con una potencia de 100 Mw, con movimientos oscilatorios sobre la herida quirúrgica. En el grupo control, se llevó a cabo el mismo procedimiento, sin la activación del láser terapéutico. Se registraron dolor postoperatorio, inflamación y medicación de rescate. El grupo experimental mostró una disminución en la intensidad del dolor posterior a la cirugía periapical en comparacióncon el grupo control (p<0.05). No se encontró diferencia estadísticamente significativa entre los grupos entérminos de inflamación. Seis pacientes del grupo control requirieron medicación de rescate. El uso de LTBNE en el manejo postoperatorio de pacientes sometidos a cirugíaperiapical, usando el protocolo del presente estudio redujo el dolor postoperatorio...

O efeito da laserterapia de baixa potência em aspectos histológicos em um modelo experimental de lesão muscular por estiramento controlado em ratos / The effect of low-level laser therapy in histological aspects in a model of experimental muscle injury in rat controlled muscle strain

Estiramento muscular e outras desordens musculoesqueléticas são as principais causas que desabilitam atletas e praticantes de atividades físicas. Seu tratamento inclui AINES que desencadeiam vários efeitos adversos. Objetivo: o objetivo do estudo foi avaliar o efeito dos tratamentos com Laserterapia de Baixa Potência e do anti-inflamatório diclofenaco, tanto individualmente quanto combinados (laser + aplicação por vias tópica ou intramuscular de diclofenaco) em aspectos histológicos no modelo experimental de lesão muscular por estiramento controlado em ratos. Materiais e Métodos: a lesão por estiramento foi induzida, por sobre carga, no músculo tibial anterior de ratos (n=6). O grupo controle não recebeu tratamento, grupos lesados receberam um único tratamento com diclofenaco através das vias tópica ou intramuscular, irradiação com laser (3 J, 830 nm, 100 mW) ou os dois tratamentos conjuntamente, laser e diclofenaco, totalizando seis grupos experimentais. Os tratamentos foram realizados 1 hora após a lesão. O músculo tibial foi removido para análise histológica, três horas após a indução da lesão e também seis horas após indução. Resultados e discussão: a avaliação histológica demonstrou uma melhor organização estrutural do tecido muscular, células bem delineadas e menor quantidade de fibras fragmentadas e menor descontinuidade de acidofilia nos grupos tratados com laser e diclofenaco, nas duas vias de aplicação, tanto no período de 3 horas quanto no de 6 horas após a lesão. Conclusão: a irradiação do laser de baixa potência conjuntamente ao diclofenaco tópico e intramuscular melhorou aspectos histológicos do tecido muscular, após lesão por estiramento, na fase aguda quando comparado com os demais tratamentos...

Muscle stretch and other musculoskeletal disorders are the main causes that disable athletes and fitness enthusiasts. His treatment includes NAIDs that trigger various adverse effects. Objective: the objective of the study the effect of treatments with Low Power Laser (LPL) Therapy and the anti-inflammatory diclofenac, both individually and combined (LPL + intramuscular or topical application of diclofenac pathways) in histological aspects in an experimental model was to evaluate muscle injury in rats controlled stretch. Materials and Methods: the injury was induced by muscle stretch, overload, the tibialis anterior muscle of rats (n = 6). The control group received no treatment, injured groups received a single treatment with diclofenac through the anti-inflammatory topical or intramuscular (AT and AIM), irradiation with LPL (3 J 830 nm, 100 mW), or the two treatments together, LPL and diclofenac (LPL/LPL or AT/AIM), totaling six experimental groups. All treatments were performed 1 hour after the injury. The right anterior tibial muscle was removed for histological analysis, within 3 hours after induction of the lesion and also 12 hours after induction. Results and discussion: histological evaluation in this study showed a better estructural organization of muscle tissue, cells and less well defined amount of fragmented fibers in the group treated with LPL and LPL AT + 3J 3J + AIM in both the 3-hour period and in 6 hours following injury. Conclusion: treatment with LPL jointly to the topic and intramuscular diclofenac improved the histological aspects of muscle tissue after stretch injury in the acute phase compared with the other treatments...

Laser terapêutico e células inflamatórias - parte 1: mastócitos* / Therapeutic laser and inflammatory cells - part 1: mast cells

O presente estudo avaliou a quantidade de mastócitos após irradiação do laser não cirúrgico λ685 nm. Dezoito ratos machos, linhagem Wistar (250 a 300 gramas), nos quais foram realizadas feridas cirúrgicas padronizadas, foram distribuídos em seis grupos, três experimentais (com quatro ratos) e três controles (com dois ratos). Os grupos experimentais foram irradiados em quatro pontos perilesionais equidistantes (0,5 J/cm², 35 mW, 35 Hz e 17 segundos). Os grupos-controles não foram irradiados. Os animais foram mortos 6, 12 e 24 horas após a irradiação, sendo obtidas peças que seguiram para processamento laboratorial de rotina. O estudo das lâminas foi realizado por meio da contagem absoluta dos mastócitos pelo método esteriológico. Os resultados obtidos demonstraram que, nas primeiras 6 e 12 horas, após a irradiação laser, existe uma diminuição no número total de mastócitos, estatisticamente significante, quando comparados aos grupos controles, porém, após 24 horas, não existem diferenças no número de mastócitos entre os grupos experimental e controle. Baseados nos resultados obtidos com o protocolo de aplicação da luz laser utilizado, para esse modelo animal, pôde-se concluir que a luz laser é capaz de diminuir o número total de mastócitos após uma única irradiação.

This study measured the variation in the total number of mast cells after low level laser therapy (λ= 685 nm) using a stereological method. Eighteen male Wistar rats (250 to 300 grams) with standardized surgical wounds were randomly distributed into 6 groups - 3 study groups with 4 rats each, and 3 control groups with 2 rats each. In the study groups, four equidistant spots around the standardized wound were irradiated (0.5 J/cm², 35 mW, 35 Hz, 17 seconds). The control groups were not irradiated. The animals were killed at 6, 12 and 24 hours after laser therapy. Biological specimens were harvested and routinely processed; slides were prepared and stained with toluidine blue. The total number of mast cells was counted using the stereological method. A statistically significant decrease in the total number of mast cells was observed at 6 and 12 hours after irradiation. However, there was nodifference in the number of mast cells between study and control groups at 24 hours. Our results showed that one single irradiation with laser light reduced the total number of mast cells in the animal model used in this study.

Laser terapêutico e células inflamatórias - parte 2: neutrófilos* / Therapeutic laser and inflammatory cells - part 2: neutrophils

O objetivo deste trabalho foi estudar a intensidade do infiltrado inflamatório agudo, presente em tecido conjuntivo perilesional do dorso de ratos submetidos à irradiação laser de baixa potência (λ 685 nm) após uma única aplicação. Foram utilizados dezoito ratos machos, linhagem Wistar, de 250 a 300 gramas, nos quais foram realizadas feridas cirúrgicas padronizadas. A amostra foi constituída de seis grupos, três experimentais e três controles, compostos por quatro e dois ratos, cada grupo, respectivamente. Os grupos experimentais foram irradiados em quatro pontos perilesionais equidistantes, com uma única dose de 0,5J/cm² por ponto, com potência de 35 mW, frequência de 35 pulsos por segundo e tempo de aplicação por ponto de 17 s. Os grupos-controles não foram irradiados. Os animais foram mortos 6, 12 e 24 horas após a irradiação, sendo obtidas peças que seguiram para processamento laboratorial de rotina. O estudo das lâminas foi realizado através da descrição e contagem absoluta dos granulócitos pelo método esteriológico. Os resultados obtidos demonstraram que há uma diminuição no número total de granulócitos, não significante estatisticamente (p≥0,05), quando comparados aos grupos controles. Concluiu-se que a luz laser é capaz de diminuir a intensidade do infiltrado inflamatório após uma única irradiação.

The aim of this work was study the intensity of acute inflammatory infiltrate inconnective tissue after low level laser therapy (λ = 685 nm) irradiation. Eighteen maleWistar rats (250 to 300 grams) with standardized surgical wounds were randomlydistributed into 6 groups - 3 study groups with 4 rats each, and 3 control groups with2 rats each. In the study groups, four equidistant spots around the standardizedwound were irradiated (0.5 J/ cm², 35 mW, 35 Hz, 17 seconds). The control groupswere not irradiated. The animals were killed at 6, 12 and 24 hours after laser therapy.Biological specimens were harvested and routinely processed. The total number of granulocyteswascounted using the stereological method. A non-statistically significant decrease in thetotal number granulocytes was observed in the all study groups. Our results showedthat one single irradiation with laser light reduced the total number of graunulocytesin the animal model used in this study.

Efeito dos laseres de baixa intensidade na proliferação e diferenciação de osteoblastos humanos / Low level laser effects in proliferation and differentiation of human osteoblasts

Dentre os vários compostos utilizados na pesquisa e na terapia de doenças osteo-degenerativas, a fototerapia com laseres de baixa potência (LLLT) e os diodos emissores de luz (LEDs) vem sendo investigada com o intuito de avaliar seus efeitos no metabolismo ósseo. Estes, que possuem comprimentos de ondas específicos, atuam na biomodulação das células, funcionando como um agente terapêutico, reequilibrando e normalizando a sua atividade. No entanto, pouco se sabe sobre o efeito dos diferentes espectros na proliferação e diferenciação de osteoblastos humanos, bem como seus efeitos no metabolismo celular como a síntese e a ativação de proteínas sinalizadoras envolvidas nesses processos. Diante disso, o objetivo deste trabalho foi avaliar, comparativamente, a influência da fototerapia com LLLT e LED na proliferação e diferenciação de osteoblastos humanos. Além disso, investigamos o envolvimento da ativação da via de sinalização ERK1,2 nestas respostas, utilizando o seu inibidor específico e/ou avaliando a sua ativação durante a proliferação e após fototerapia. Para esse estudo, osteoblastos humanos (HOAL) foram cultivados em meio de cultura DMEM suplementado com 10% de soro fetal bovino (SFB) e incubados em estufa de CO2. As células foram irradiadas pontualmente com os laseres vermelho (660nm), infravermelho (780nm) e LED (637nm), nas doses de 10, 20 e 50 J/cm2 na potência de 40mW, após adesão celular. Após 24, 48, e 72 horas foram realizados os ensaios de redução do MTT (brometo de 3-(4,5-dimetiltiazol-2-yl)-2,5- difeniltetrazólio) e cristal violeta (CV) para avaliar a viabilidade das células e após 72 horas foi realizada a análise da proliferação por citometria de fluxo nos quais os resultados sugerem aumento de células viáveis ou proliferação quando estimuladas pelos diferentes espectros. Após a verificação do efeito positivo dos laseres e LED na viabilidade e/ou proliferação, foi realizada a análise da ativação da proteína intracelular ERK...

Among the various compounds used in research and bone degenerative diseases therapy, phototherapy with low level laser (LLLT) and light emitting diodes (LEDs) has been investigated in order to evaluate its effects on bone metabolism. Those, who have specific wavelengths, act in biomodulation cells functioning as a therapeutic agent, rebalancing and normalizing their activity. However, little is known about the effect of the different spectra in the proliferation and differentiation of human osteoblasts and their effects on cellular metabolism as well as the synthesis and activation of signaling proteins involved in these processes. Therefore, the aim of this study was to compare the influence of LLLT and LED phototherapy in the proliferation and differentiation of human osteoblasts. In addition, we investigated the involvement of activation of ERK1,2 signaling pathway these responses using its specific inhibitor and/or evaluating their activation during the proliferation and after phototherapy. For this study, human osteoblasts (HOAL) were cultured in DMEM culture medium supplemented with 10 % fetal bovine serum (FBS) and incubated in CO2 incubator . Cells were irradiated with punctual red lasers (660nm), infrared (780nm) and LED (637nm) at doses of 10, 20 and 50 J/cm2 in power 40mW, after cell adhesion. After 24, 48, and 72 hours, MTT assay (- (4,5- dimethylthiazol-2- yl) -2,5 - diphenyltetrazolium bromide 3 ) and violet crystal (CV) were performed to assess the viability of cells and after 72 hours, was performed of proliferation analysis by flow cytometry. The results suggest an increase in viable and proliferation of cells when stimulated by different spectra. After checking the positive effect of lasers and LED viability and/or proliferation, analysis of ERK activation of intracellular protein by western blotting using a specific antibody was performed 10 minutes after the spot irradiation. We show that irradiation of HOAL cells with LLLT at a dose...

Bone Healing Capacity in the Fracture of Rabbit Mandibular Bone Using Low-Level Laser

The concept of biostimulation of wounds by low-level laser therapy (LLLT) is attracting considerable attention. Although its effect on whole tissues has been studied quite extensively, the biological and cellular mechanisms underlying LLLT have not been clarified. In an experimental radius fracture in rabbits, Tang and Chai reported that LLLT enhanced the activity of red blood cells, macrophages, fibroblasts, chondrocytes, and osteoclasts within the fracture area. The purpose of the present study was to evaluate the effect of LLLT with a GaAlAs diode laser device on bone healing in rabbit mandibular fractures. We use 12 rabbits for this study. All rabbits were fractured mandible angle area using saw in anesthetic condition. In control group(n=6), none treatment was performed at fracture site. In experimental group(n=6), LLLT with a GaAlAs diode laser was radiated at fracture site daily for 7 days. All rabbits were sacrificed at 6 weeks later from performed fracture day. We studied the immunohistochemical staining of CD34 and Vimentin and the histochemical analysis for calcium and phosphorus content. The results were as follows. 1. In the histological and immunohistological staining, after 6week, fibroblasts, osteogenic cells and collgen fibers were observed more in experimental group than in control group. 2. In the histochemical analysis, the amount of calcium and phosphorus contents of the experimental group were more than the control group. From the results obtained, we suggest that the bone healing is stimulated by low-level laser irradiation in bone fractures.

Effect of GaInAIP (685 nm) radiation on lipopolyssacharide induced rat trachea hyperreactivity

O objetivo do presente estudo foi investigar o efeito do laser de baixa potência (LLLT) na hiper-reatividade da traquéia de ratos Wistar macho(RTHR) depois da administração de lipopolissacarídeo (LPS)

Effect of Low Level Laser Therapy on Healing of Open Skin Wounds in Rats

This research was focused on overall examination of tissue alteration, wound healing promotion. After the hair on the dorsal surface was shaved, 5x5mm oval skin defect was formed. Experimental wounds of right side were irradiated on every day for 90 second with Ga-Al-As semi-conductor laser. Left side wounds served as control group. The rats were sacrificed on the 1st, 3rd, 5th, 7th, 14th, 21th day. For light microscopically, parafin section were stained with H&E, MT. The outcomes were as follows : 1. On 1st day, experimental and control group were seen acute inflammatory cell infiltration, edema. 2. On the 3rd days, both groups were seen crust development, collagen, blood vessel proliferation. 3. On the 5th days, experimental group were reduced edema and inflammatory cell infiltration than control group. 4. On the 7th days, both groups were observed edema, inflammatory cell infiltration disappearance and keratinocytes motility from wound defect. 5. On the 14th days, experimental group appeared collagen, blood vessel proliferation and hair follicle than control group. 6. On the 21th days, both groups were seen normal status re-epithelization. According to the above results, The wound-healing stimulated by laser radiation involves an increased rate of epithelial growth. LLLT was confirmed that it has fibroblast, blood vessel proliferation, influence initial wound healing process.

Effects of Low Level Laser Therapy on Herpetic Neuralgia / 대한마취과학회지

There are several methods for the treatment of herpetic neuralgia, but there is no method that results in complete remission. Laser has lately come into use to reduce several acute or chronic pains. In order to determine the degree of pain relief by lasers, 26 patients of herpetic neuralgia were irradiated with both He-Ne and Ga-Al-As lasers twice to theree times per week and the results were analysed using visual analogue scale. The results were as follows. 1) The improving rate after 15 irradiations of laser was 63% 2)The highest improving rate(24%) was shown after one irradiation of laser(p<0.05). 3) Only one patient above age 60(3.8%) developed postherpetic neuralgia. 4) There was no significant differenc of effects of LLLT between above and below age 60. These results suggest that LLLT is non-invasive and simple method which was effective not only in controlling the herpetic neuralgia but in perventing the postherpetic neuralgia.

Effects of Low Level Laser Therapy on Herpetic Neuralgia / 대한마취과학회지

There are several methods for the treatment of herpetic neuralgia, but there is no method that results in complete remission. Laser has lately come into use to reduce several acute or chronic pains. In order to determine the degree of pain relief by lasers, 26 patients of herpetic neuralgia were irradiated with both He-Ne and Ga-Al-As lasers twice to theree times per week and the results were analysed using visual analogue scale. The results were as follows. 1) The improving rate after 15 irradiations of laser was 63% 2)The highest improving rate(24%) was shown after one irradiation of laser(p<0.05). 3) Only one patient above age 60(3.8%) developed postherpetic neuralgia. 4) There was no significant differenc of effects of LLLT between above and below age 60. These results suggest that LLLT is non-invasive and simple method which was effective not only in controlling the herpetic neuralgia but in perventing the postherpetic neuralgia.