Antimicrobial photodynamic therapy with methylene blue and its derivatives in animal studies: Systematic review.

BACKGROUND: Infections are complications in the wound healing process, and their treatment can lead to antibiotic overuse and bacterial resistance. Antimicrobial photodynamic therapy (aPDT) is used to treat infectious diseases caused by fungi, viruses, or bacteria. Methylene blue (MB) and its derivatives are commonly used dyes in antimicrobial photodynamic therapy (aPDT-MB). METHODS: This study is a PRISMA systematic review of animal models used to discuss the usefulness and therapeutic parameters of aPDT-MB or its derivatives for treating infected skin wounds. RESULTS: After an extensive literature review, 13 controlled trials totaling 261 animals were selected to evaluate skin infection by leishmaniasis and cutaneous bacterial and fungal infections. All studies found results favoring the use of aPDT-MB. Great variability in parameters was found for radiant exposure from 12 to 360 J/cm2, MB diluted in saline solution or distilled water, irradiation time from 40 to 3600 s, irradiance most commonly at a maximum of 100 mW/cm2, and wavelength used mainly in the 630-670 nm range. CONCLUSION: MB is a safe and promising agent used as a photosensitizer in aPDT for skin-infected lesions. There is great variability in the parameters found. Comparisons concerning concentration, irradiation time, and light intensity need to be performed.

Antimicrobial Photodynamic Therapy in the Nasal Decolonization of Maintenance Hemodialysis Patients: A Pilot Randomized Trial.

RATIONALE & OBJECTIVE: Infections are an important cause of mortality among patients receiving maintenance hemodialysis. Staphylococcus aureus is a frequent etiological agent, and previous nasal colonization is a risk factor for infection. Repeated antimicrobial decolonization reduces infection in this population but can induce antibiotic resistance. We compared photodynamic therapy, a promising bactericidal treatment that does not induce resistance, to mupirocin treatment among nasal carriers of S aureus. STUDY DESIGN: Randomized controlled pilot study. SETTING & PARTICIPANTS: 34 patients receiving maintenance hemodialysis who had nasal carriage of S aureus. INTERVENTIONS: Patients were randomly assigned to decolonization with a single application of photodynamic therapy (wavelength of 660nm, 400mW/cm2, 300 seconds, methylene blue 0.01%) or with a topical mupirocin regimen (twice a day for 5 days). OUTCOME: Nasal swabs were collected at time 0 (when the carrier state was identified), directly after treatment completion, 1 month after treatment, and 3 months after treatment. Bacterial isolates were subjected to proteomic analysis to identify the species present, and antimicrobial susceptibility was characterized. RESULTS: All 17 participants randomized to photodynamic therapy and 13 of 17 (77%) randomized to mupirocin were adherent to treatment. Directly after treatment was completed, 12 participants receiving photodynamic therapy (71%) and 13 participants treated with mupirocin (77%) had cultures that were negative for S aureus (risk ratio, 0.92 [95% CI, 0.61-1.38]; P=0.9). Of the patients who had negative cultures directly after completion of photodynamic therapy, 67% were recolonized within 3 months. There were no adverse events in the photodynamic therapy group. LIMITATIONS: Testing was restricted to assessing nasal colonization; infectious complications were not assessed. CONCLUSIONS: Photodynamic therapy is a feasible approach to treating nasal carriage of S aureus. Future larger studies should be conducted to determine whether photodynamic therapy is equivalent to the standard of care with mupirocin. FUNDING: Government grant (National Council for Scientific and Technological Development process 3146682020-9). TRIAL REGISTRATION: Registered at ClinicalTrials.gov with study number NCT04047914.

Effects of systemic vascular photobiomodulation using LED or laser on sensory-motor recovery following a peripheral nerve injury in Wistar rats.

Peripheral nerve injury (PNI) is associated with considerable functional impairment. Photobiomodulation (PBM) has demonstrated positive effects regarding neuromuscular repair after PNI when applied locally to the nerve or injured muscle. However, the effects of systemic PBM with transcutaneous application over an important artery, which is also denominated vascular PBM (VPBM), remain unclear. The aim of the study was to compare the effects of VPBM with low-level laser (LLL) and light-emitting diode (LED) on gait, sensitivity and muscle morphology following a PNI. PNI was induced on Wistar rats using the sciatic nerve crushing technique. VPBM was performed over the rat's artery tail region with LED (850 nm, 40 mW, 3.2 J) and LLL (780 nm, 40 mW, 3.2 J). Gait functionality, mechanical (nociceptive) sensitivity, and morphology of the tibialis anterior muscle were evaluated at 7, 14, and 21 days after injury. An improvement in functional gait was shown in the VPBM-LLL group in all periods. Motor sensitivity was found after 14 days in the VPBM-LLL group. The left/right (L/R) muscle mass ratio revealed a reduction in muscle atrophy in the VPBM-LLL group at 7 days. Muscle fiber diameter increased in the VPBM-LED group at 14 days and increases in the cross-section area were found in the VPBM-LED and VPBM-LLL groups at 7 days. VPBM with both light sources (LED and LLL) positively modulated functioning and neuromuscular recovery following sciatic nerve injury in rats, with more pronounced results when using LLL.

Influence of conditioned medium from squamous cell carcinoma of the tongue on lymphoblasts and peripheral blood mononuclear cells.

BACKGROUND: Squamous cell carcinoma (SCC) is the most common malignant neoplasm of the oral cavity and is associated with high morbidity and mortality. Attention has been given to the role of inflammatory cells in carcinogenesis because of the ability of cancer cells to subvert the immune response. However, little is known about how molecules from neoplastic cells interact with lymphoblasts and circulating immune cells. This study aimed to understand the mechanisms by which SCC cells modulate the immune response by analyzing the influence of conditioned medium derived from SCC cell lines on immune cells. METHODS: Lymphoblastic cells (CEM) and peripheral blood mononuclear cells (PBMC) were cultured in a conditioned medium derived from squamous cell carcinoma cells (SCC9 or SCC4) and analyzed for cell viability, CD4/CD8/FOXP3 profile by flow cytometry, and chemokine levels. RESULTS: Conditioned medium derived from SCC4 and SCC9 presented higher concentrations of IL-6 and IL-8 than IL-1ß, IL-10, and IFN-γ. CEM and PBMCs when cultured with conditioned medium derived from SCC4 and SCC9 reduced IL-1ß, IL-8, and IFN-γ concentrations. Conditioned medium from SCC4 increased CD4+ population in both CEM and PBMCs, while in conditioned medium from SCC9 it occurred only in PBMCs. PBMCs when cultured with both conditioned mediums increased CD8+ /FOXP3+ cells. CEM cells when cultured with conditioned medium derived from SCC4 and SCC9 reduced. CONCLUSION: Collectively, our results suggest that the products derived from squamous cell carcinoma on inflammatory cells can promote an immunosuppressed environment by reducing cell viability, changing cytokine expression, and altering the cell immunoprofile.

Effects of the invasive and non-invasive systemic photobiomodulation using low-level laser in experimental models: A systematic review.

Systemic photobiomodulation (PBM) of the blood or over blood vessels has been associated with bio-stimulating, vasodilating, and anti-inflammatory properties. This treatment modality has been used for modulating inflammatory processes, tissue repair, atherosclerosis, and systemic arterial hypertension, and is described more often in clinical studies than experimental models. Therefore, the aim of the present study was to conduct a literature review regarding the effect of systemic PBM involving the intravascular laser irradiation of blood (ILIB) or non-invasive vascular photobiomodulation (VPBM) using low-level laser (LLL) in experimental (animal) models. The PubMed/MEDLINE®, Scopus, SPIE Digital Library, and Web of Science databases were searched for articles on the use of VPBM with LLL in animal models. Nine original articles met the inclusion criteria and were critically evaluated. The variables of interest were the dosimetric laser parameters, different methods for delivering energy, and the main results. The use laser in the red spectrum was more prevalent and VPBM (non-invasive) predominated over ILIB (invasive). No standardization was found in the dosimetric parameters. However, the studies showed the positive effects of VPBM on arterial pressure and blood circulation, the positive effects of ILIB on blood composition and hematological markers, as well as positive effects of both forms of systemic PBM (ILIB and VPBM) on the tissue repair process. In conclusion, the studies evaluated in the present review showed that the use of systemic PBM with ILIB or non-invasive VPBM induced positive effects, modulating metabolic conditions and tissue repair. However, there is a need for standardization in the dosimetric parameters for the different conditions and processes evaluated using experimental models.

Abnormal Activity of Masticatory Muscles in Patients with Diagnosis of Cerebral Palsy. A Systematic Review and Meta-Analysis of Observational Studies.

AIMS: to map and synthesize the results from studies that assessed whether individuals diagnosed with cerebral palsy (CP) have abnormal masseter and temporal muscles activation during the masticatory cycle. METHODS: Six databases were searched for comparative observational studies assessing masticatory muscles activation in individuals with CP through electromyography analysis. Methodological quality was evaluated using the Joanna Briggs Critical Appraisal Checklist. Outcome data were combined in meta-analysis using the Review Manager software. RESULTS: We included five cross-sectional studies with an overall low risk of bias. Meta-analyses showed no difference between CP and healthy individuals regarding maximum voluntary isometric contraction: right masseter (Standard mean difference [SMD] - 0.95; 95% CI -2.03 to 0.13); left masseter (SMD -0.92; 95% CI -1.93 to 0.09); right temporal (SMD -0.72; 95% CI -1.63 to 0.18); and left temporal (SMD -0.68; 95% CI -1.76 to 0.40). Electrical activity amplitude in the inactive period was superior in the CP group, and maximum bite pressure presented higher values in the control group (Mean difference [MD] - 17.38; CI 95% -26.62 to -10.15). CONCLUSIONS: Based on observational studies with a lower level of evidence, individuals with CP seem to present difficulties activating masticatory muscles. Future prospective cohort studies with rigorous methodology are still necessary to support these findings. PROSPERO register CRD42020208444.

Simultaneous red and infrared light-emitting diodes reduced pain in individuals with temporomandibular disorder: a randomized, controlled, double-blind, clinical trial.

The aim of the present study was to evaluate the effects of photobiomodulation (PBM) with the simultaneous use of red and infrared LEDs on pain and mandibular range of motion in individuals with temporomandibular disorder (TMD). Eighteen participants were randomly allocated to an LED group or control group. The device had 18 red LEDs (660 nm) and 18 infrared LEDs (850 nm), with a total power irradiated of 126 mW and 75.6 J per point. The device was placed in the regions of the temporomandibular joint (TMJ) and masticatory muscles once per day three times per week for 2 weeks. Pain intensity was measured using the visual analog scale (VAS). Mandibular range of motion was determined using digital calipers and considering different conditions (unassisted opening without pain, maximum opening with and without assistance, right and left lateral movements, and protrusion). Evaluations were performed before treatment, immediately after the first LED irradiation session and at the end of six sessions. A significant reduction in pain intensity was found in the LED group at the end of treatment compared to the control group (p < 0.001) as well as in the comparison between the pretreatment and end of treatment evaluations (p < 0.001). Regarding mandibular movements, no statistically significant differences between the LED group and control group were found at the end of treatment for any of the conditions analyzed or in the comparison between the beginning and end of treatment with LED. Photobiomodulation using a cluster with red and infrared LEDs induced a reduction in pain in individuals with temporomandibular disorder but did not alter mandibular range of motion in these individuals. Trial registration number: NCT03696706; retrospectively registered (ClinicalTrials.gov).

The effects of photobiomodulation using LED on the repair process of skin graft donor sites.

The benefits of photobiomodulation (PBM) applied to wounds are well-described in the literature; however, its effects in skin graft donor sites have been poorly studied. The aim of this study is to evaluate the effects of LED PBM on re-epithelialization and wound quality of the skin donor site and on pain during repair process. This is a case series study that part of the patients received standard treatment and the others received standard treatment combined with PBM. Data collection was performed at the Burn Unit at a Public Hospital, Brazil. The study had 21 participants and 25 donor sites, 13 in the control group (conventional treatment with Membracel® bandage) and 12 in the experimental group (Membracel® + LED). Irradiation parameters were 1.53 J/cm2, 2.55 mW/cm2, 660 nm, 600 s in the immediate postoperative period as well as on the 1st, 3rd, 5th, and 7th days postoperatively. Pain was measured using the visual analog scale. The Bates-Jensen scale was used to monitor the re-epithelialization process and measurements were performed of donor skin sites in the postoperative period. Quantitative variables were expressed as mean ± standard deviation or median and interquartile range [p25; p75]. The comparison of the distribution of these variables between groups was performed using the Mann-Whitney test. No differences between groups were found for re-epithelialization time, area or quality of the wound. Regarding pain, a significant reduction was found on the 5th postoperative day in the experimental group compared to the control group. PBM did not induce changes in the re-epithelialization period, wound area or wound quality scores of the Bates-Jensen Scale but did induce a reduction in pain compared to the group treated with Membracel® alone.

Effects of different protocols of defocused high-power laser on the viability and migration of myoblasts-a comparative in vitro study.

The aim of the present study was to analyze for the first time the effect of photobiomodulation therapy (PBMT) using defocused high-power laser (DHPL) in myoblast cell line C2C12 viability and migration and compare them with low-power laser therapy. Cells were divided into 9 groups: Sham irradiation 10% fetal bovine serum (FBS); Sham irradiation 5%FBS; low-power laser 0.1 W; DHPL 810 1 W; DHPL 810 2 W; DHPL 980 1 W; DHPL 980 2 W; DHPL dual 1 W; DHPL dual 2 W. To simulate stress conditions, all groups exposed to irradiation were maintained in DMEM 5% FBS. The impact of therapies on cell viability was assessed through sulforhodamine B assay and on cells migration through scratch assays and time-lapse. Myoblast viability was not modified by PBMT protocols. All PBMT protocols were able to accelerate the scratch closure after 6 and 18 h of the first irradiation (p < 0.001). Also, an increase in migration speed, with a more pronounced effect of DHPL laser using dual-wavelength protocol with 2 W was observed (p < 0.001). In conclusion, the diverse PBMT protocols used in this study accelerated the C2C12 myoblasts migration, with 2-W dual-wavelength outstanding as the most effective protocol tested. Benefits from treating muscle injuries with PBMT appear to be related to its capacity to induce cell migration without notable impact on cell viability.

Effect of photobiomodulation on fatigue in individuals with relapsing-remitting multiple sclerosis: a pilot study.

Multiple sclerosis is an autoimmune disease of the central nervous system characterized by inflammation and destruction of the myelin sheath. Fatigue is one of the main symptoms of this disease, with a negative impact on quality of life and few treatment options. Photobiomodulation is used for several inflammatory conditions and may be beneficial for the treatment of fatigue in individuals with multiple sclerosis. Conduct a pilot study to analyze the effect of photobiomodulation on fatigue in individuals with relapsing-remitting multiple sclerosis. The participants were recruited from the UNINOVE Integrated Health Clinic and randomly allocated to two groups: group 1, administration of photobiomodulation (808 nm, 36 J for 360 s) under the tongue and group 2, administration of photobiomodulation over the radial artery. Fatigue was measured using the Modified Fatigue Impact Scale (MFIS). No significant differences were found regarding the total MFIS score or subscale scores (p < 0.05, two-way ANOVA). Photobiomodulation with the parameters employed in the present study had no effect on fatigue in individuals with multiple sclerosis. ClinicalTrials.gov Identifier: NCT03360487.

Effect of antimicrobial photodynamic therapy with red led and methylene blue on the reduction of halitosis: controlled microbiological clinical trial.

To determine the effect of antimicrobial photodynamic therapy (aPDT) using a red light-emitting diode (LED) on the reduction of halitosis and microbiological levels in the tongue coating immediately after irradiation, 7, 14, and 30 days after treatment. Forty-five young adults diagnosed with halitosis were allocated to three groups: G1, aPDT with 0.005% methylene blue and red LED (660 nm, four irradiation points, 90 s per point, power of 400 mW, 36 J per point, radiant exposure of 95 J/cm2, continuous wave); G2, tongue scraping; and G3, tongue scraping and aPDT. Gas chromatography was performed before and immediately after treatment, as well as at the different follow-up times. Microbiological samples were collected at the same times from the dorsum of the tongue, and bacteria were quantified in the samples using real-time PCRq. The Wilcoxon test was used for the intragroup analyses, and the Kruskal-Wallis test was used for the intergroup analyses. In the intragroup analyses, differences were found before and immediately after treatment in all groups (p < 0.05). The effect was maintained after 7 days only in the tongue scraping group (p < 0.05). In the intergroup analysis, no statistically significant differences were found among the groups (p > 0.05). For the microbiological analyses, no statistically significant differences were found in the groups/bacteria that were analyzed (p > 0.05). aPDT using a red LED and 0.005% methylene blue caused an immediate reduction in halitosis, but the effect was not maintained after 7, 14, or 30 days. No reduction occurred in the number of bacteria investigated or the quantification of universal 16S rRNA. ClinicalTrials.gov Identifier: NCT03656419.

Effect of Photodynamic Therapy on Halitosis: A Systematic Review of Randomized Controlled Trials.

BACKGROUND: This systematic review aimed to assess the effectiveness and safety of aPDT for the treatment of halitosis. METHODS: Search strategies were conducted in October 2021 without language or data restrictions, on the following databases: MEDLINE, EMBASE, CENTRAL, LILACS and BBO, as well as a manual search. Randomized clinical trials (RCTs) with parallel design were considered for inclusion, assessing individuals (adolescents and adults) with a clinical diagnosis of halitosis treated with photodynamic therapy (aPDT). Primary outcomes assessed were halitosis measurements, adverse events and quality of life. The risk of bias for each included study was evaluated with the Cochrane Risk of Bias tool and the certainty of the body of the evidence was assessed with the GRADe approach. RESULTS: Six RCTs (total of 225 participants) were included and due to clinical diversities it was not possible to group the outcome data in meta-analyses. Based on very low-certainty evidence (GRADE) the results showed that, when compared to tongue scraper, aPDT seems to promote a little to no difference in reducing halitosis and in the microbiological analysis. No adverse events were reported. Considering aPDT combined with tongue scraper, better outcome results were observed when compared to tongue scraper alone. CONCLUSIONS: Based on very low-certainty evidence, the findings of this review are uncertain about the effects of aPDT for halitosis control. Further RCTs with higher number of participants and long term assessments need to be conducted to support the use of this intervention. The protocol was registered in the PROSPERO database (number: CRD42020215319) on 19 November 2020-retrospectively registered.

Low-level laser or LED photobiomodulation on oral mucositis in pediatric patients under high doses of methotrexate: prospective, randomized, controlled trial.

PURPOSE: The objective of the present study was to compare the efficacy of photobiomodulation with low-level laser therapy (LLLT) or light-emitting diode therapy (LEDT) devices for the prevention and treatment of oral mucositis in pediatric patients diagnosed with acute lymphoblastic leukemia undergoing chemotherapy with high doses of methotrexate (MTX). METHODS: Eighty patients were randomly divided into two groups: LLLT and LEDT. Both protocols were applied with the same energy and radiant exposure. The protocols started in the beginning of high doses MTX and finished when the patients were discharged from the hospital or there was oral mucositis resolution. The oral mucositis was assessed during each session in accordance to the World Health Organization (WHO) score. The patients' self-assessed pain was scored on a visual analog scale (VAS). RESULTS: The incidence of oral mucositis was similar to LLLT and LEDT, 10% and 12.5%, respectively. Both groups required the same number of days to reach score of zero for mucositis and pain (p > 0. 05), and there was no significant difference in mean VAS between the groups. CONCLUSIONS: These findings suggest that LEDT has similar effects to LLLT to avoid and treat oral mucositis. Brazilian Clinical Trial Registry with #U1111-1221-5943.

Photobiomodulation alters the viability of HUVECs cells.

The aim of the present study was to investigate the influence of low-level red (660 nm) and infrared (780 nm) laser with four different radiance exposures on human umbilical vein endothelial cells (HUVECs) in vitro. HUVECs (1.5 × 104) were incubated in 96-well culture plates. The cells were maintained in M199 medium supplemented with 20% fetal bovine serum, 1% antibiotic (penicillin), 1% anti-mycotic (Fungizone), and 1% endothelial cell growth supplement. After centrifugation, irradiations (660/780 nm, 40 mW, 1, 5, 10, and 20 J/cm2, 1 s, 5 s, 10 s, and 20 s, respectively, total energy 0.4 J, 2 J, 4 J, and 8 J, and beam spot size at target 0.04 cm2) were performed at the bottom of Falcon tubes such that the laser beam directly reached the cell without passing through the culture medium. The cells were divided into groups based on radiant exposures. Cell viability and protein concentration were verified after 1, 2, 3, 6, 8, and 10 days. Red laser increased the cell viability and protein concentration in all groups (three-way ANOVA, p < 0.05) beginning on the second day. The greatest peak compared with the control was found when the radiant exposure was 5 J/cm2 and 10 J/cm2. Infrared laser inhibited cell viability and modulated the protein concentration in the cells, with the highest peak protein concentration found on the second day in the group with radiant exposure of 1 J/cm2 and 10 J/cm2 (three-way ANOVA, p < 0.05). Red laser increased the viability and concentration of total proteins in HUVECs, whereas infrared laser had an inhibitory effect on cell viability, while maintaining the total protein concentration similar to that found in the control group.

Effects of photobiomodulation on cellular viability and cancer stem cell phenotype in oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) is the most common head and neck malignancy; it has been shown that cancer stem cells (CSC) are present in OSCC and associated with tumor growth, invasion, metastasis, and therapeutic resistance. Photobiomodulation (PBM) is an alternative tool for oncologic treatment adverse effects such as oral mucositis (OM); however, controversy exists regarding the undesirable effects of PBM on tumor or CSC. This study aimed to evaluate in vitro, the effects of PBM, with the same dosimetric parameters as those used in the clinic for OM prevention and treatment, on OSCC cellular viability, as well as PBM's effect on CSC properties and its phenotype. OSCC cell lines were submitted to single or daily PBM with 3 J/cm2 and 6 J/cm2 and then the cellular viability was evaluated by MTT, NRU (neutral red uptake), and CVS (crystal violet staining). The CSC populations were evaluated by clonogenic formation assay, flow cytometry, and RT-qPCR. The single PBM with the 3 J/cm2 group was associated with increased cellular viability. Daily PBM with 3 J/cm2 and 6 J/cm2 was associated with a significant decrease in cellular viability. Additionally, daily PBM was not able to promote CSC self-renewal or the CD44high/ESAlow and CD44high/ESAhigh cellular phenotypes. Moreover, a decrease in the number of spheres and in the expression of the CSC related gene BMI1 was observed after daily PBM with 6 J/cm2. Daily PBM with 3 J/cm2 and 6 J/cm2 showed an inhibitory effect on cellular viability and was not able to promote the CSC self-renewal or phenotype.

Effect of Blue Light on Acne Vulgaris: A Systematic Review.

Acne is a dermatosis that affects almost 90% of the adolescent population worldwide and its treatment is performed with retinoids, antimicrobials, acids, and topical or systemic antibiotics. Side effects such as skin irritation in addition to microbial resistance to antibiotics are the main side effects found. Phototherapy with blue light is being used as an alternative treatment. Our objective was to analyze the use of blue light to treat inflammatory acne. We conducted a systematic literature review, following the recommendation PRISMA (Preferred Reporting Items for Systematic Reviews and MetaAnalyses), including in the sample randomized clinical trial studies that compared blue light with another intervention as control. The research was carried out in the PUBMED and WEB of SCIENCE databases and the methodological quality of the studies evaluated were made by the Cochrane Collaboration Bias Risk Scale. After the exclusion of duplicates, the titles and abstracts of 81 articles were evaluated, and 50 articles were selected for full reading, including in the review at the end 8 articles. Studies have shown significant improvements in the overall picture of acne. It is concluded that despite the great potential in its use in the treatment of acne, there is a need for more detailed trials on the effect of blue light on the treatment of inflammatory acne.

Photobiomodulation in oral mucositis in patients with head and neck cancer: a systematic review and meta-analysis followed by a cost-effectiveness analysis.

BACKGROUND: Oral mucositis (OM) is an oral toxicity caused by cancer treatment, found often in patients with head and neck cancer. Low-intensity laser therapy for OM has anti-inflammatory, analgesic, and tissue reparative properties. OBJECTIVE: The objective of this work is to perform a systematic review and meta-analysis of the randomized clinical trials of OM laser therapy in patients undergoing treatment for head and neck cancers, followed by a cost-effectiveness analysis of the therapy. METHOD: The search terms, mucositis and phototherapy, laser therapy and mucositis, photobiomodulation and mucositis, and low-level laser therapy and mucositis, were used to search the databases of PubMed, Web of Science, and MEDLINE. Randomized clinical trials were divided into two groups: one treated with laser therapy and the other given a placebo. Only 13 studies were included in the systematic review, and 6 studies in the meta-analysis. RESULTS: The results of the systematic review and meta-analysis show that the laser therapy presented good results in clinical improvement and pain reduction, decreasing the patients' likelihood of developing OM, with degrees of debilitating lesions, to 64% (RR = 0.36 [95% CI = 0.29-0.44]). The cost-effectiveness analysis revealed an incremental cost of R$ 3687.53 for the laser group, with an incremental effectiveness of 132.2. The incremental cost-effectiveness ratio (ICER) was 27.89, for the severe OM cases that were avoided. CONCLUSION: It was concluded, therefore, that photobiomodulation for OM in patients receiving head and neck cancer treatment was clinically effective and cost-effective.

Effects of Dexamethasone and Photobiomodulation on Pain, Swelling, and Quality of Life After Buccal Fat Pad Removal: A Clinical Trial.

PURPOSE: In this study we aimed to compare the effects of photobiomodulation (PBM) and dexamethasone (DXM) on pain, swelling, and the quality-of-life (QOL) of patients submitted to buccal fat pad removal. PATIENTS AND METHODS: A total of 20 patients with pseudoherniation of buccal fat pad were included in the present study. The patients were divided randomly into 2 groups: the PBM group (660 nm, 100 mW, 6 seconds, 2 J/cm2) and the DXM group (4 mg every 8 hours for 3 days after the procedure). Pain levels were evaluated using a visual analog scale at days 2 and 4 after surgery, whereas the edema was evaluated by measuring the distance between 6 reference points: tragus, pogonion of the soft tissue, lateral eye commissure, the gonial angle, nose wing, and mouth commissure at days 2, 4, 7, 15, 30, 60, and 90. The QOL was evaluated using the Oral Health Impact Profile 14 questionnaire at days 2 and 4 after surgery. RESULTS: There were no differences between the PBM and DXM groups in pain or edema. In terms of the QOL, the PBM group was significantly more comfortable when chewing than the DXM group (P < .05) CONCLUSION: The use of PBM at a power of 100 mW and 2 J/cm2 per point had similar effects to oral DXM for the control of pain and edema, as well as in the QOL, except for masticatory function, which was significantly better in the PBM group.

Effects of photobiomodulation in the treatment of fractures: a systematic review and meta-analysis of randomized clinical trials.

Several therapeutic strategies have been proposed to optimize the conventional treatment of fractures. Photobiomodulation (PBM) appears to help reduce pain and control inflammation, and it also accelerates bone repair. This systematic review aimed to evaluate the effectiveness and safety of PBM with low-level laser therapy (LLLT) in the bone fracture healing process. We included randomized controlled trials (RCTs) comparing the effects of PBM with those of any other intervention in adults with lower or upper limb bone fractures. The primary outcomes investigated were pain reduction, radiographic healing, and adverse events. The searches were conducted in October 2018. Two RCTs were included that compared PBM to the placebo. A meta-analysis showed significant difference in favor of PBM for pain reduction (MD 1.19, 95% CI [0.61 to 1.77], 106 participants, two RCTs), but this difference was not clinically significant. One RCT (50 participants) showed a clinical and statistical improvement in physical function (MD - 14.60, 95% CI [- 21.39 to - 7.81]) and no difference in radiographic healing, regarding absence of fracture line (RR 1.00, 95% CI [0.93 to 1.08]) and visible bone callus (RR 0.33, 95% CI [0.01 to 7.81]). The certainty of evidence was classified as low to very low. Based on the evidence of low to very low certainty, PBM seems to be associated with the improvement of pain and function. Therefore, new RCTs are required that meet the recommendations of CONSORT to prove the effectiveness and safety of this intervention and support its recommendation in clinical practice.

Sensory and motor responses after photobiomodulation associated with physiotherapy in patients with incomplete spinal cord injury: clinical, randomized trial.

Complete or incomplete spinal cord injury (SCI) results in permanent neurological deficits due to the interruption of nerve impulses, causing the loss of motor and sensory function, which leads to a reduction in quality of life. The focus of rehabilitation for such individuals is to improve quality of life and promote functional recovery. Photobiomodulation (PBM) has proved to be promising complementary treatment in cases of SCI. The aim of the present study was to investigate the effects of PBM combined with physiotherapy on sensory-motor responses below the level of the injury and quality of life in individuals with SCI. Thirty participants were randomized for allocation to the PBM group (active PBM + physiotherapy) or sham group (sham PBM + physiotherapy). Physiotherapy was administered three times a week. Sensitivity and motor skills were evaluated using the ASIA impairment scale. Quality of life was assessed using the WHOQOL-BREF questionnaire. The data were analyzed with the level of significance set to 5%. Improvements in sensitivity and an increase in the perception of muscle contraction were found in the active PBM group 30 days after treatment compared with the sham group. The results of the WHOQOL-BREF questionnaire revealed a significant difference in general quality of life favoring the active PBM group over the sham group after treatment. Physiotherapy combined with PBM leads to better sensory-motor recovery in patients with SCI as well as a better perception of health and quality of life. Trial registration identifier: NCT03031223.