Oral mucositis (OM) is the most common debilitat- ing complication among patients undergoing hematopoietic stem cell transplantation (HSCT). Photobiomodulation thera- py (PBM) has shown beneficial effects in the treatment of OM, but few studies have evaluated its biological effects. This study evaluated the effect of PBM on the reduction of OM severity in patients undergoing HSCT and its relation to the modulation of the inflammatory response. Fifty-one pa- tients were randomly assigned to two groups: PBM [submitted to PBM from admission (AD) to D+7] (n = 27) and control (n = 24) [received oral hygiene]. OM severity was assessed daily using the WHO scale. Saliva samples were collected on AD, D+7, and hospital discharge (HD) to measure CXCL8/ interleukin 8, using cytometric bead array analysis and nitrite (NO) and myeloperoxidase (MPO) using colorimetric methods. PBM significantly reduced the severity of OM from D+7 to D+11 (p < 0.05). All non-interventional patients (controls) who developed grade 2 or higher OM induced an increase of CXCL8 in saliva (n = 14) on D+7. PBM led to a decrease in CXCL8 on D+7 in 85% of patients, while 70.8% of patients in the control group presented an increase in this chemokine (p = 0.007). NO decreased from AD to D+7 in the PBM group (p > 0.05). MPO significantly decreased on D+7 in both groups (p < 0.05). PBM brought about a reduction in the severity of OM in patients undergoing HSCT, and this reduction was associated with a decrease in CXCL8 salivary levels.

Patients undergoing hematopoietic stem cell transplantation (HSCT) are submitted to a conditioning regimen of high-dose chemotherapy, which usually results in oral ulcerations. Oral mucositis (OM) is a common, painful and debilitating toxicity side effect of autologous and allogeneic HSCT. Currently, there is no intervention that is completely successful in preventing OM. Low-level laser therapy (LLLT) has been reported to produce basic effects such as anti-inflammatory activity, biomodulation and analgesia, however the biochemical responses are not well understood. The aim of this study was to evaluate the effect of LLLT on the severity of chemotherapy-induced OM and on inflammatory mediator concentration in saliva and blood in HSCT patients. Twenty-five patients were randomly assigned to 2 groups: control and laser. The laser group (n=11) received the hospital oral hygiene protocol, and low-intensity laser irradiation (660 nm, 40 mW, 4J/cm2 ) was applied from the first day of the conditioning regimen until D+7. The control group (n=14) received only the hospital oral hygiene protocol. The severity of OM (WHO scale) was scored from D0 to day 20 after transplantation (D+20). Saliva and blood were collected from all patients on admission and one day before the transplantation (D-1), on days 3 and 7 after transplantation (D+3 and D+7) and on marrow engraftment day (ME). The concentration of inflammatory mediators (TNF-α, IL-6, IL-1β, IL-10, TGF-β, EGF, FGF, VEGF, MMP2/TIMP-2, MMP9/TIMP-2) were measured using the enzyme-linked immunosorbent assay (ELISA) test. Clinical results showed less severe OM in the laser group (p < 0.05). On analysing the inflammatory mediators, the LLLT group showed increased MMP2/TIMP2 levels in saliva on D+7 (p = 0.04). In addition, significant differences were also observed for IL-10 in blood plasma on D+7 and on ME, when compared to the control group (p < 0.05). No significant differences in saliva and blood were observed for the other inflammatory mediators investigated. We concluded that LLLT was clinically effective in reducing the severity of chemotherapy-induced OM in HSCT patients, and that its mechanism of action does not seem to be completely linked to the modulation of pro- or anti-inflammatory cytokines, growth factors or matrix metalloproteinases.

This study aimed to verify the effectiveness of using a low-level laser therapy protocol to reduce swelling, pain and neurosensory disturbance after orthognathic surgeries. Ten patients who underwent bilateral sagittal split (BSSO) with Le Fort I osteotomy and had low-level laser therapy on one side of the jaw were evaluated over a period of 60 days. The protocol used was intra oral application after surgery (λ = 660 nm (Red), ED = 5J/cm2, t = 10 s / point, P = 20 mW, E = 1.2 J per point). And extra oral application (λ = 789 nm infra-red), DE = 30J/cm2, t = 20 s / point, P = 60 mW, E = 1.2 J per point). After the fourth day, ten intraoral and extraoral applications were performed (λ = 780nm (infrared), DE = 70J/cm2, P = 70 mW, t = 40s / point, E = 2.8 J, per point). Irradiated and non-irradiated side data were compared post-operatively. In all assessments except the immediate post operative assessment, swelling and pain decreased. There is recovery of sensitivity on both sides, but on the irradiated side, recovery is faster and almost normal at the last evaluation. The data for the irradiated and non-irradiated sides were compared post-operatively. Fifteen, 30 and 60 days after surgery, sensitivity was recovered on both sides, but on the irradiated side, recovery was faster and was almost complete at the time of the last evaluation. Irradiated and non-irradiated sides were compared regarding swelling coefficient and Visual Analogue Scale for pain assessment. There were no significant differences between irradiated and non-irradiated sides regarding swelling and pain in the immediate postoperative assessment. Swelling significantly decreased in the irradiated side in the following post-operative assessments, from 2.15 to 0.21 (non irradiated side: 2.72 to 1.29). Self-reported pain was less intense in the irradiated side in the 24-hr (1.20 vs 3.4) and 3-day (0.60 vs 2.10) assessments, but after 7 days of surgery either side did not show any pain. This lower-level laser therapy protocol can improve tissue response and reduce pain and swelling resulting from orthognathic surgeries and accelerate the recovery of neurosensory disorders resulting from BSSO.

O propósito deste estudo foi analisar o comportamento do osso alveolar na remodelação óssea sob carga fisiológica e ortopédica após a disjunção rápida da sutura palatina mediana durante 14 dias, com e sem aplicação de laser de baixa potência e comparar imagens obtidas por técnica radiográfica convencional com microtomografias computadorizadas. O aparelho de laser utilizado foi de diodo de arsenieto de gálio-alumínio (AlGaAs) (830&#61544;m; 100mW, onda contínua, 126J/cm2, 29 segundos) aplicado à sutura palatina mediana de ratos Wistar, machos, de 6 semanas de vida. Foram utilizados 65 ratos divididos em um grupo controle (GC) contendo 5 ratos e dois experimentais I e II (GE I e GE II), com 30 ratos cada, ambos GE submetidos à disjunção imediata, sendo que o GE II foi irradiado imediatamente após a disjunção. Os GE I e II foram subdivididos em períodos de disjunção imediata, 6, 24, 48 horas, 7 e 14 dias. Dois amostras de cada período dos GC e GE foram radiografadas (convencional) e processadas para captura de imagens em scanner micro-CT (Scanco Medical, Zurik, Suíça), com 24KV de energia e 3,8μm de resolução espacial e o restante foram processadas para serem analisadas histologicamente coradas com hematoxilina e eosina e tricrômico de Masson. Os resultados foram avaliados histológica e radiograficamente. O trabeculado ósseo recém-formado a partir dos bordos ósseos da sutura foi observado nos períodos de 2, 7 e 14 dias do GE II, 7 e 14 dias do GE I. O presente experimento demonstrou que a atividade osteoblástica aumenta a atividade da osteosíntese de modo mais expressivo após aplicação do laser de baixa potência, porem é necessários mais estudos em biologia molecular para desvendar os seus efeitos ao nível celular. As microtomografias computadorizadas mostraram maior riqueza de detalhes para analisar o rompimento da sutura palatina mediana e seu reparo com o depósito de tecido ósseo do que as radiografias convencionais.

O objetivo desse trabalho foi avaliar a aplicação da Photobiomodulation Therapy (PBM-T) local e sistêmica para a redução da dor no pós-operatório de pacientes submetidos a exodontias de terceiros molares. Foram selecionados 30 pacientes das Clínicas Odontológicas da Pontifícia Universidade Católica de Campinas com indicação de exodontia de dois terceiros molares. O tratamento proposto para cada dente foi determinado de forma randomizada: Sham (S) ou Fotobiomodulação (PBM T). Grupo S (n=30): após a exodontia do terceiro molar, foi feita a simulação da aplicação da PBM-T local e sistêmica. Grupo PBM-T (n=30): após a exodontia do terceiro molar, foi aplicado o protocolo da PBM-T local e sistêmica. Em ambos os grupos, o paciente fez uso de paracetamol durante três dias de pós-operatório. A PBM-T local foi feita com laser de baixa potência, intraoralmente, com irradiação em três pontos na região alveolar (oclusal, lingual e vestibular), com energia de 3 J por ponto, durante 30 segundos em cada ponto, comprimento de onda de 808 nm, potência de 100 mW, spot de saída de 0.098 cm², e de modo contínuo. A PBM-T sistêmica foi feita com o mesmo equipamento de laser, na artéria radial, com energia de 60 J, durante 10 minutos, com o comprimento de onda de 660 nm. Houve um intervalo de 3 semanas entre uma exodontia e outra do mesmo paciente. O desfecho primário foi a avaliação da dor através da Escala Visual Analógica (VAS). Os desfechos secundários foram a avaliação do edema e aplicação do questionário de qualidade de vida utilizando o Perfil de Impacto na Saúde Bucal de 14 itens (OHIP 14). As avaliações foram feitas antes da cirurgia, imediatamente após a cirurgia, 24 horas, 48 horas e no sétimo dia de pós-operatório. Os resultados obtidos foram analisados pelo teste de Kruskal-Wallis (Student-Newman-Keuls). Houve aumento significativo da dor no grupo Sham após 24 e 48 horas da exodontia (p=0.0000). A sensibilidade dolorosa diminuiu após 7 dias da exodontia no grupo Sham. No grupo da PBM-T, não houve o aparecimento da dor durante os períodos experimentais, mostrando que a PBM-T local e sistêmica foi efetiva no controle da dor após a exodontia dos terceiros molares (p=0.2151). A PBM-T teve efeito modulatório do processo inflamatório após a exodontia dos terceiros molares e acarretou em maior conforto pós-operatório. Pode-se concluir que a PBM-T local e sistêmica pode ser uma alternativa para o controle da dor, edema e melhora da qualidade de vida dos pacientes submetidos a exodontia de terceiros molares.

Low-level laser therapy has been used to speed up healing process of pressure ulcers due to its antiinflammatory, analgesic, anti-edematous, and scarring effects. However there is no consensus on its effect on infected ulcers. The aim of this study was to verify the bactericidal effect of low-level laser therapy (InGaP, 670 nm) and photodynamic therapy (PDT) at 2, 4 and 6 J/cm² doses, onto gram-negative and gram-positive bacteria in vitro. Thirty two Petri plates were prepared, 16 with Pseudomonas aeruginosa and 16 with Staphilococcus aureus, and divided into eight subgroups each: three subgroups treated with 2 J/cm², 4 J/cm², and 6 J/cm² laser; three subgroups treated with 2 J/cm², 4 J/cm², and 6 J/cm² PDT; one treated solely with photosensitiser; and a non-treated (control) subgroup. Laser and PDT groups were irradiated once and incubated for 24 hours; the other two subgroups underwent no irradiation. Cultures were visually analysed in search of inhibition haloes. In all subgroups, for both bacteria, no inhibition or growing signs could be detected. Hence neither low-level laser or PDT (InGaP, 670 nm) produced any bactericidal or bacteriostatic effect, nor any biostimulation effect, onto analysed bacteria.

Os nervos periféricos sofrem constantes lesões de origem traumática, o que resulta em perdas funcionais. A terapia com laser de baixa potência vem sendo utilizada para minimizar os efeitos maléficos da inflamação e acelerar o processo de cicatrização dos tecidos lesados. Este estudo teve como objetivo verificar o efeito da irradiação do laser 830 nm no comportamento do nervo isquiático de ratos submetido a esmagamento. Foram utilizados 20 ratos, todos tendo tido o nervo isquiático esmagado, divididos em 4 grupos (n=5): P7 e P14, tratamento placebo por 7 e 14 dias; L7 e L14, tratamento por laser (dosagem de 4 J/cm²) por 7 e 14 dias. Os animais dos grupos P7 e P14 foram submetidos aos mesmos procedimentos, mas com o laser desligado. Os parâmetros analisados foram presença de infiltrado inflamatório e fibroblastos, destruição da bainha de mielina e degeneração axonal. Na análise estatística foi observada diferença estatística com relação a três parâmetros: os animais do grupo L14 apresentaram maior quantidade de fibroblastos (p=0,0001), menor degeneração da bainha de mielina (p=0,007) e menor quantidade de infiltrado inflamatório (p=0,001). A aplicação do laser de baixa potência contribuiu para a redução do processo inflamatório decorrente da lesão do nervo isquiático de ratos.

A fadiga muscular é uma nova área de pesquisa em laserterapia, com poucos estudos conduzidos. Embora a laserterapia de baixa potência (LBP) previamente ao exercício tenha apresentado resultados positivos no retardo da fadiga musculoesquelética, ainda não foi estudada utilizando-se a dinamometria isocinética para mensurar desempenho e fadiga muscular. Este estudo tem o objetivo de avaliar os efeitos da LBP (655 nm, 50 mW, 2,4 J por ponto e 12 J de energia total) sobre o desempenho e fadiga muscular do músculo tibial anterior, utilizando dinamometria isocinética (30 repetições de contração concêntrica) em 14 indivíduos saudáveis sedentários do sexo masculino. Os voluntários foram avaliados ao efetuar 30 repetições isocinéticas de dorsiflexão de tornozelo à velocidade angular de 240°.seg-1. Os resultados mostram que, quando os voluntários foram tratados com LBP antes do exercício, os valores do pico de torque (30,91±5,86 N.m) foram significativamente superiores, comparados a três medições anteriores sem a aplicação de LBP (24,92±7,45 N.m, p

Low intensity laser can be used as a promising alternative in the treatment of periodontal disease. Objective The aim of this study was to evaluate low-level laser therapy (LLLT) as an adjuvant treatment for scaling and root planing (SRP) for the treatment of induced periodontitis in simvastatin-modified rats. Material and Methods A total of 180 rats were evenly divided into two groups: Veh – receiving oral administration of polyethylene glycol (vehicle); S – receiving oral administration of Simvastatin. Periodontal disease was induced in both groups at the first mandibular molar. After seven days, the ligature was removed and the animals were divided into subgroups according to the following local treatments: NT – no treatment; SRP – scaling and root planing and irrigation with saline solution; and LLLT ¬– SRP and laser irradiation (660 nm; 0.03 W; 4 J). Ten animals in each subgroup/local treatment were euthanized at 7, 15 and 30 days. Samples of gingival tissue were processed to analyze the tissue oxidative damage and radiographic analysis. Levels of oxidative stress were analyzed by the expressions of Tripeptideglutathione (TG), Malondialdehyde (MDA) and Carbonylated Proteins (CP). Results The animals in S group had higher levels of TG and lower levels of MDA and CP compared with Veh group (p

Implant surface decontamination is a challenging procedure for therapy of peri-implant disease. Objective: This study aimed to compare the effectiveness of decontamination on oral biofilm-contaminated titanium surfaces in Er:YAG laser, Er, Cr:YSGG laser, and plastic curette. Methodology: For oral biofilms formation, six participants wore an acrylic splint with eight titanium discs in the maxillary arch for 72 hours. A total of 48 contaminated discs were distributed among four groups: untreated control; decontamination with plastic curettes; Er, Cr:YSGG laser; and Er:YAG laser irradiation. Complete plaque removal was estimated using naked-eye and the time taken was recorded; the residual plaque area was measured and the morphological alteration of the specimen surface was observed by scanning electron microscopy. The total bacterial load and the viability of adherent bacteria were quantified by live or dead cell labeling with fluorescence microscopy. Results: The mean treatment time significantly decreased based on the treatment used in the following order: Er:YAG, Er, Cr:YSGG laser, and plastic curettes (234.9±25.4 sec, 156.1±12.7 sec, and 126.4±18.6 sec, P=0.000). The mean RPA in the Er, Cr:YSGG laser group (7.0±2.5%) was lower than Er:YAG and plastic curettes groups (10.3±2.4%, 12.3±3.6%, p=0.023). The viable bacteria on the titanium surface after Er, Cr:YSGG laser irradiation was significantly lower compared to the decontamination with plastic curette (P=0.05) but it was not significantly different from the Er:YAG laser irradiation. Conclusion: We found that Er:YAG laser and Er, Cr:YSGG laser irradiation were effective methods for decontaminations without surface alterations.