Ação do laser terapêutico e do ultrassom na regeneração nervosa periférica

OBJETIVO: Avaliar a ação precoce do laser terapêutico e do ultrassom no processo de regeneração de uma lesão experimental em ratos. MÉTODO: Utilizou-se 24 ratos. Dezoito foram submetidos ao procedimento cirúrgico de lesão do nervo ciático por compressão, através de uma pinça hemostática acima da fossa poplítea. Os animais foram divididos em três grupos com seis animais em cada. Grupo controle normal. GI: controle lesado sem intervenção terapêutica. GII: intervenção terapêutica do laser ArGaAl. GIII: intervenção terapêutica do ultrassom Pulsado. Iniciamos as intervenções terapêuticas 24 horas após a lesão, com aplicações diárias, por um período de quatorze dias consecutivos. RESULTADOS: Ao avaliar a perimetria dos músculos da coxa direita obteve-se os seguintes valores médios de diminuição (mm), para cada grupo GI: 0,45; GII: 0,42; GIII: 0,40. Quanto ao tempo de deslocamento tanto o GII e GIII apresentaram diferença significativa, quando comparados ao GI. Na avaliação final do IFC o GII sobressaiu ao GIII. Quanto a cicatrização observou-se grande melhora no GII e GIII. CONCLUSÃO: Os resultados evidenciaram que a recuperação nervosa foi maior com a aplicação do laser. Nível de evidência II, Estudos terapêuticos - Investigação dos resultados do tratamento

Tratamento alternativo para neuralgia pós-herpética após transplante pulmonar. Relato de caso

JUSTIFICATIVA E OBJETIVOS: A neuralgia pós-herpética (NPH) é a dor que permanece após o desaparecimento do episódio agudo de herpes zoster. O objetivo deste estudo foi relatar o tratamento da dor da NPH em paciente transplantado pulmonar. RELATO DO CASO: Paciente do sexo masculino, 73 anos, transplantado pulmonar há três anos, em uso de imunossupressores. Desenvolveu quadro de herpes zoster há um ano, com vesículas no oitavo espaço intercostal do hemitórax direito (HTD). O tratamento foi efetivo com ganciclovir; entretanto, o paciente evoluiu com dor em queimação, intensa, constante, com piora no último mês, com intensidade pela escala visual numérica (EVN) de 9, mesmo com uso de 600 mg/dia de gabapentina. Ao exame físico apresentava uma lesão avermelhada no HTD, hiperestésica. Foi instituído tratamento com gabapentina (900 mg), amitriptilina (25 mg), dipirona (8 g) e oxicodona (20 mg) ao dia. Feita a aplicação de laser de baixa intensidade (LBI) diariamente por uma semana, seguido de tratamento com amitriptilina tópica a 4%. A intensidade da dor diminuiu para 5. A frequência de aplicação do LBI diminuiu para uma vez a cada dois dias com melhora significativa com EVN entre 1 e 2. Teve alta hospitalar, com 25 mg/dia de amitriptilina oral e amitriptilina tópica a 4%. CONCLUSÃO: O uso do LBI e da amitriptilina tópica foi eficaz para remissão do quadro doloroso.

Terapia pulpar em dentes decíduos: possibilidades terapêuticas baseadas em evidências

Introduction: Pulpotomy of primary teeth has been the treatment of choice in cases of inflammation of the coronal pulp caused by caries or trauma with no involvement of the radicular pulp, thus avoiding the premature loss of the teeth. Not only is the diagnosis of the inflamed dental pulp required for this therapy to succeed, but also the selection of an effective and biocompatible medicament. However, none of the drugs available and recommended for pulpotomy therapy present all the requirements of an ideal pulp capping agent. Objective: Through a systematic literature review, between the years of 2000 and 2011, focusing in randomized clinical trials, systematic reviews and meta-analysis, aiming to analyze and discuss based on alternatives for the treatment of pulpotomy in human deciduous teeth. Conclusion: Scientific evidences showed that the medicaments and techniques influence were few. Thus, further and well-designed studies are suggested for clarification. The information generated in such experiments may contribute to a better understanding of the mechanisms of pulp therapy to new therapeutic approaches aimed at improving pulp therapy in deciduous teeth.

Tratamento de sequelas de queimadura de face com laser de CO2 fracionado em pacientes com fototipos III a VI

INTRODUÇÃO: Relatos sobre melhora em cicatrizes pós-traumáticas ou patológicas com o uso do laser de CO2 fracionado (CO2F) concluem tratar-se de tecnologia segura e efetiva, apesar de utilizado apenas em pacientes com fototipos II a III. O objetivo deste estudo foi avaliar a eficácia do CO2F em pacientes com sequela de queimadura facial com fototipos III a VI. MÉTODO: No total, 14 pacientes, com média de idade de 29 anos, portadores de sequela de queimadura facial e fototipos III a VI, foram submetidos a uma aplicação do laser de CO2F. Após dois meses, a queimadura foi avaliada por meio de escala com 6 parâmetros: cor, textura, hidratação, irregularidades de superfície, volume e distensibilidade. RESULTADOS: A duração média da dor foi de 19 horas; do edema, 1,3 dia; e da hiperemia, 6,5 dias. A queda das crostas finalizou entre 5 dias e 36 dias, com média de 13,4 dias. Dois meses após a sessão, 5 pacientes evoluíram com hipocromia puntiforme no padrão quadriculado correspondente aos pontos de ablação do laser. A satisfação subjetiva dos avaliadores (pacientes e médicos) com o tratamento foi de 84,6%. Para os pacientes, houve melhora das irregularidades de superfície, da distensibilidade e da textura da pele (57% dos casos), da hidratação (43%), do volume (28%) e da cor (14%). Para os médicos, houve melhora das irregularidades de superfície e da distensibilidade (43%). CONCLUSÕES: O tratamento com laser de CO2F com parâmetros suaves foi bem tolerado e apresentou alto índice de satisfação em pacientes com sequela de queimadura facial, com melhora de textura, distensibilidade e irregularidades de superfície. A alta incidência de hipopigmentação é um fator a ser considerado na indicação do laser de CO2F em pacientes com fototipos IV a VI.

Laser therapy and pain-related behavior after injury of the inferior alveolar nerve: possible involvement of neurotrophins

Nerve-related complications have been frequently reported in dental procedures, and a very frequent type of occurrence involves the inferior alveolar nerve (IAN). The nerve injury in humans often results in persistent pain accompanied by allodynia and hyperalgesia. In this investigation, we used an experimental IAN injury in rats, which was induced by a Crile hemostatic clamp, to evaluate the effects of laser therapy on nerve repair. We also studied the nociceptive behavior (von Frey hair test) before and after the injury and the behavioral effects of treatment with laser therapy (emitting a wavelength of 904 nm, output power of 70 Wpk, a spot area of *0.1 cm2, frequency of 9500 Hz, pulse time 60 ns and an energy density of 6 J/cm2). As neurotrophins are essential for the process of nerve regeneration, we used immunoblotting techniques to preliminarily examine the effects of laser therapy on the expression of nerve growth factor (NGF) and brainderived neurotrophic factor (BDNF). The injured animals treated with laser exhibited an improved nociceptive behavior. In irradiated animals, there was an enhanced expression of NGF (53%) and a decreased BDNF expression (40%) after laser therapy. These results indicate that BDNF plays a locally crucial role in pain-related behavior development after IAN injury, increasing after lesions (in parallel to the installation of pain behavior) and decreasing with laser therapy (in parallel to the improvement of pain behavior). On the other hand, NGF probably contributes to the repair of nerve tissue, in addition to improving the pain-related behavior.

How low-level laser therapy can change mechanical properties of cells.

Low level laser therapy is used as a treatment of several conditions, including inflammatory processes and wound healing. Possible changes in mechanical properties of cells, caused by illumination, are investigated with optical magnetic twisting cytometry (OMTC), which is a technique used to evaluate mechanical properties in cell culture. Ferromagnetic micro beads are bound to cell cytoskeleton, the beads are magnetized vertically and a horizontal twisting magnetic field is applied causing a torque that moves the beads and deforms the cell, the beads rotate and displace. Based on the lateral displacement of the beads, elastic shear and loss moduli are obtained. Samples of human bronchial epithelial cell culture were divided in two groups: one was illuminated with a 660 nm red laser, 30 mW power, 0.75 W/cm2 irradiance, during different time intervals, and the other one, the control group, was not illuminated. The values of the mechanical constants of the cells of the control group showed a tendency of increasing with the time out of the incubator. On the other hand, the illuminated group showed constancy on the behavior of both moduli, keeping the normal conditions of the cell culture. Those results indicate that illumination can induce cells to homeostasis, and OMTC is sensitive to observe departures from the steady conditions. Hence, OMTC is an important technique which can be used to aggregate knowledge on the light effect in cell cytoskeleton and even on the low level laser therapy mechanisms in inflammatory processes and/or wound healing.

Low-level laser therapy in pediatric Bell's palsy: case report in a three-year-old child

Objectives: The objective of this study was to apply low-level laser therapy (LLLT) to accelerate the recovery process of a child patient with Bell's palsy (BP). Design: This was a prospective study. Subject: The subject was a three-year-old boy with a sudden onset of facial asymmetry due to an unknown cause. Materials and methods: The low-level laser source used was a gallium aluminum arsenide semiconductor diode laser device (660nm and 780 nm). No steroids or other medications were given to the child. The laser beam with a 0.04-cm2 spot area, and an aperture with approximately 1-mm diameter, was applied in a continuous emission mode in direct contact with the facial area. The duration of a laser session was between 15 and 30 minutes, depending on the chosen points and the area being treated. Light was applied 10 seconds per point on a maximum number of 80 points, when the entire affected (right) side of the face was irradiated, based on the small laser beam spot size. According to the acupuncture literature, this treatment could also be carried out using 10-20 Chinese acupuncture points, located unilaterally on the face. In this case study, more points were used because the entire affected side of the face (a large area) was irradiated instead of using acupuncture points. Outcome measures: The House-Brackmann grading system was used to monitor the evolution of facial nerve motor function. Photographs were taken after every session, always using the same camera and the same magnitude. The three-year-old boy recovered completely from BP after 11 sessions of LLLT. There were 4 sessions a week for the first 2 weeks, and the total treatment time was 3 weeks. Results: The result of this study was the improvement of facial movement and facial symmetry, with complete reestablishment to normality. Conclusions: LLLT may be an alternative to speed up facial normality in pediatric BP.

Necrosis response to photodynamic therapy using light pulses in the femtosecond regime

One of the clinical limitations of the photodynamic therapy (PDT) is the reduced light penetration into biological tissues. Pulsed lasers may present advantages concerning photodynamic response when compared to continuous wave (CW) lasers operating under the same average power conditions. The aim of this study was to investigate PDT-induced response when using femtosecond laser (FSL) and a first-generation photosensitizer (Photogem) to evaluate the induced depth of necrosis. The in vitro photodegradation of the sensitizer was monitored during illumination either with CWor an FSL as an indirect measurement of the PDT response. Healthy liver of Wistar rats was used to evaluate the tissue response. The photosensitizer was endovenously injected and 30 min after, an energy dose of 150 Jcm-2 was delivered to the liver surface. We observed that the photodegradation rate evaluated via fluorescence spectroscopy was higher for the FSL illumination. The FSL-PDT produced a necrosis nearly twice as deep when compared to the CW-PDT. An increase of the tissue temperature during the application was measured and was not higher than 2.5 °C for the CW laser and not higher than 4.5 °C for the pulsed laser. FSL should be considered as an alternative in PDT applications for improving the results in the treatment of bulky tumors where higher light penetration is required.

A 12-month follow-up of hypopigmentation after laser hair removal

Introduction: Laser hair removal is becoming an increasingly popular alternative to traditional methods such as shaving, waxing, among other methods. Semiconductor diode lasers are considered the most efficient light sources available and are especially well suited for clinical applications including hair reduction. The effectiveness of laser hair reduction depends on many variables, including the skin type of the patient. Material and Methods: A patient with Fitzpatrick Skin Type IV was submitted to laser hair removal of the arms with a high-power diode laser system with long pulses with a wavelength of 800 nm, a fluence of 40 J/cm2 and a pulse width of 20 ms. A 12-month follow-up assessment was performed and included photography and questionnaire. Results: Hypopigmentation was observed after a single laser hair removal section. After 6 months with the area totally covered, a gradual suntan with a sun screen lotion with an SPF of 15 was prescribed by the dermatologist. After 12 months of the initial treatment, a complete recovery of the hypopigmentation was achieved. Conclusion: Although a safe procedure, lasers for hair removal may be associated with adverse side effects including undesired pigment alterations. Before starting a laser hair removal treatment, patients seeking the eradication of hair should be informed that temporary, and possibly permanent, pigmentary changes may occur.