Effect of photobiomodulation in an experimental in vitro model of asthma-Copd overlap.

The objective of the study was to evaluate the effect of photobiomodulation (PBM) with laser on the inflammatory process in an experimental in vitro model of ACO. The groups were: (1) human bronchial epithelial cells (BEAS-2B); (2) BEAS-2B cells treated with dexamethasone; (3) BEAS-2B cells irradiated with laser; (4) BEAS-2B cells stimulated with cigarette smoke extract (CSE) + House Dust Mite (HDM); (5) BEAS-2B cells stimulated with CSE + HDM and treated with dexamethasone; (6) BEAS-2B cells incubated with CSE + HDM and irradiated with laser. After 24 h, cytokines were quantified. There was a reduction in TNF-α, IL-1ß, IL-6, IL-4, IL-5, IL-13, IL-17, IL-21, IL-23, and an increase in IL-10 and IFN-γ in cells from the laser-irradiated ACO group compared to only ACO group. With these results, we can suggest that photobiomodulation acts in the modulation of inflammation observed in ACO, and may be a treatment option.

Photobiomodulation efficacy in age-related macular degeneration: a systematic review and meta-analysis of randomized clinical trials.

BACKGROUND: Age-related macular degeneration (AMD) is a leading cause of vision loss. Photobiomodulation (PBM) offers a controversial approach for managing dry AMD, aiming to halt or reverse progression through mitochondrial activity modulation. However, the efficacy and clinical relevance of PBM as a potential approach for managing dry AMD remain debated. METHODS: We systematically searched PubMed, Embase, and Cochrane databases for randomized controlled trials (RCTs) comparing PBM versus a sham in patients with dry AMD. We performed trial sequential analysis (TSA) and minimal clinically important difference (MCID) calculations to assess statistical and clinical significance applying a random-effects model with 95% confidence intervals (CI). RESULTS: We included three RCTs comprising 247 eyes. The pooled analysis showed that PBM significant improved BCVA (MD 1.76 letters; 95% CI: 0.04 to 3.48) and drusen volume (MD -0.12 mm³; 95% CI: -0.22 to -0.02) as compared with a sham control. However, the TSA indicated that the current sample sizes were insufficient for reliable conclusions. No significant differences were observed in GA area. The MCID analysis suggested that the statistically significant results did not translate into clinically significant benefits. In the quality assessment, all studies were deemed to have a high risk of bias. CONCLUSION: This meta-analysis points limitations in the current evidence base for PBM in dry AMD treatment, with issues around small sample sizes. Statistically significant improvements do not translate into clinical benefits. The research underscores need for larger RCTs to validate PBM's therapeutic potential for dry AMD.

Effect of photobiomodulation with different wavelengths on periodontal repair in non-hyperglycemic and hyperglycemic rats.

BACKGROUND: Hyperglycemic conditions is associated with more severe periodontitis and poorer outcomes after nonsurgical periodontal treatment (NPT). Then, these patients are candidates for adjunctive therapy associated with NPT. This study evaluates the effect of photobiomodulation (PBMT) at different wavelengths on periodontal repair in non-hyperglycemic/hyperglycemic animals. MATERIALS AND METHODS: Sixty-four rats were submitted to induction of periodontitis by ligatures. Hyperglycemia was induced in half of these animals, whereas the other half remained non-hyperglycemic. The animals were subdivided into 4 groups according to the PBMT protocol applied at the time of ligature removal (n = 8): CTR: Without PBMT; IRL: PBMT with infrared laser (808 nm); RL: PBMT with red laser (660 nm); and RL-IRL: PBMT with red (660 nm) and infrared laser (808 nm). After a period of 7 days, the animals were euthanized. The parameters assessed by microtomography were the bone volume relative to total tissue volume (BV/TV%), distance from the cemento-enamel junction to the top of the bone crest (CEJ-CB), trabecular thickness, space between trabeculae, and number of trabeculae. Additionally, the percentage of inflammatory cells, blood vessels, and connective tissue matrix were assessed by histomorphometric analysis. RESULTS: PBMT reduced bone loss and increased trabecular density in hyperglycemic animals (p < .05), with RL being more effective in reducing linear bone loss (CEJ-CB), whereas RL-IRL was more effective in maintaining BV/TV%. PBMT reduced blood vessels and increased the connective tissue component in hyperglycemic animals (p < .05). RL-IRL reduced inflammatory cells regardless of the systemic condition of the animal (p < .05). CONCLUSION: PBMT (RL, RL-IRL) improves the repair of periodontal tissues in hyperglycemic animals.

Photobiomodulation with laser and led on mesenchymal stem cells viability and wound closure in vitro.

Mesenchymal stem cells can differentiate into specific cell lineages in the tissue repair process. Photobiomodulation with laser and LED is used to treat several comorbidities, can interfere in cell proliferation and viability, in addition to promoting responses related to the physical parameters adopted. Evaluate and compare the effects of laser and LED on mesenchymal cells, with different energy doses and different wavelengths, in addition to viability and wound closure. Mesenchymal stem cells derived from human adipocytes were irradiated with laser (energy of 0.5 J, 2 J and 4 J, wavelength of 660 nm and 830 nm), and LED (energy of 0.5 J, 2 J and 4 J, where lengths are 630 nm and 850 nm). The wound closure process was evaluated through monitoring the reduction of the lesion area in vitro. Viability was determined by analysis with Hoechst and Propidium Iodide markers, and quantification of viable and non-viable cells respectively Data distributions were analyzed using the Shapiro-Wilk test. Homogeneity was analyzed using Levene's test. The comparison between the parameters used was analyzed using the Two-way ANOVA test. The T test was applied to data relating to viability and lesion area. For LED photobiomodulation, only the 630 nm wavelength obtained a significant result in 24, 48 and 72 h (p = 0,027; p = 0,024; p = 0,009). The results related to the in vitro wound closure test indicate that both photobiomodulation with laser and LED demonstrated significant results considering the time it takes to approach the edges (p < 0.05). Considering the in vitro experimental conditions of the study, it is possible to conclude that the physical parameters of photobiomodulation, such as energy and wavelength, with laser or LED in mesenchymal stem cells, can play a potential role in cell viability and wound closure.

Adjunctive photobiomodulation to Basic Periodontal therapy using different low-power laser application techniques: a systematic review and meta-analysis.

To review current literature and synthesize clinical outcomes related to different low-level laser techniques as a complement to basic periodontal therapy (BPT). Electronic searches were conducted in PubMed, Cochrane, and Scopus, and clinical trials published from January 2013 to August 2023 using photobiomodulation as a complement to basic periodontal therapy, with a clear description of the laser technique, were included. The risk of bias was assessed using the Joanna Briggs Institute Critical Assessment Checklist. Estimates of interest were calculated using random effects meta-analyses. A total of 947 references were retrieved, and 22 studies were included for qualitative synthesis. Ten studies used intrasulcular laser techniques, with 89% using infrared wavelength, and 12 studies used transgingival techniques, with 61.5% using red wavelength. The frequency of photobiomodulation after BPT ranged from 1 to 9 sessions, with follow-up periods ranging from 5 days to 12 months. Risk of bias was considered low in 16 studies and moderate in six studies. Meta-analysis of 13 studies showed that BPT reduced probing depth at 4-, 12- and 24-weeks post-treatment, and improved clinical level attachment at 6-, 12- and 24-weeks post-treatment. Studies suggest that photobiomodulation may be a valuable complement in the treatment of periodontitis, especially using transgingival application technique.

Effect of combined red and infrared wavelengths on inflammation, hemorrhage, and muscle damage caused by Bothrops leucurus snake venom.

To evaluate the effects of red and infrared wavelengths, separately and combined, on the inflammatory process and collagen deposition in muscle damage caused by B. leucurus venom. 112 mice were inoculated with diluted venom (0.6mg/kg) in the gastrocnemius muscle. The animals were divided into four groups: one control (CG) and three treatments, namely: 1) red laser (λ=660 nm) (RG), 2) infrared laser (λ=808 nm) (IG) and 3) red laser (λ=660 nm) + infrared (λ=808 nm) (RIG). Each group was subdivided into four subgroups, according to the duration of treatment application (applications every 24 hours over evaluation times of up to 144 hours). A diode laser was used (0.1 W, CW, 1J/point, ED: 10 J/cm2). Both wavelengths reduced the intensity of inflammation and the combination between them significantly intensified the anti-inflammatory response. Photobiomodulation also changed the type of inflammatory infiltrate observed and RIG had the highest percentage of mononuclear cells in relation to the other groups. Hemorrhage intensity was significantly lower in treated animals and RIG had the highest number of individuals in which this variable was classified as mild. As for collagen deposition, there was a significant increase in RG in relation to CG, in RIG in relation to CG and in RIG in relation to IG. Photobiomodulation proved to be effective in the treatment of inflammation and hemorrhage caused by B. leucurus venom and stimulated collagen deposition. Better results were obtained with the combined wavelengths.

Modulation of gene expression in skin wound healing by photobiomodulation therapy: A systematic review in vivo studies.

BACKGROUND: Wound healing is a multistep process involving coordinated responses of a variety of cell types, cytokines, growth factors, and extracellular matrix (ECM) components leading to the physiological restoration of tissue integrity. Photobiomodulation therapy (PBMT) has been highlighted as an approach to improve the healing process, nonetheless at the molecular level, the effects of PBMT are not entirely understood. AIM: To systematically review publications that investigated gene expression after PBMT during in vivo skin repair. METHODS: An electronic search was undertaken in Medline Ovid (Wolters Kluwer), PubMed (National Library of Medicine), Web of Science (Thomson Reuters), Scopus (Elsevier), Embase, and LILACS databases. The search strategy was conducted from the terms: low-level light therapy, gene expression, and wound healing and their synonyms. The databases were consulted in December 2023 and no publication year limit was used. RESULTS: Eleven studies were included in this review and the expression of 186 genes was evaluated. PBMT modified the expression of several targets genes studied, such as down-regulation of genes related to extracellular matrix proteases (MMP2 and MMP9) and pro-inflammatory cytokines (IL10 and IL6) and up-regulation of DNMT3A and BFGF. CONCLUSION: This review demonstrates that PBMT is capable of regulating gene expression during wound healing. Most evidence showed a positive impact of PBMT in regulating genes linked to inflammatory cytokines improving skin wound healing. Yet, the effects of PBMT in genes involved in other mechanisms still need to be better understood.

Effect of Using Photobiomodulation (660 Nanometers) for the Treatment of Diabetic Ulcers: Protocol for a Randomized Controlled Trial.

Diabetic foot ulcers (DFUs) result in tissue damage or impairment of deeper structures that affect quality of life. The impacts are numerous, and even after a long treatment period, 65% of patients experience recurrence. Among the interventions used to accelerate the healing process of DFUs, photobiomodulation therapy (PBMT) is a painless, noninvasive, and low-cost treatment. To achieve effective therapeutic results optimal PBMT parameters are necessary. The positive effect of PBMT on diabetic cells may be dependent on fluence (J/cm2) and wavelength (nm). This double-blind, randomized clinical trial will be conducted at the University Clinic of Physical Therapy. One hundred patients will be randomly placed in 4 groups. A Laserpulse Ibramed (Helium-Neon, HeNe, 660 nm) with 20 W power will be used (continuous mode), with doses stipulated for each treatment group (GL1, 4 J/cm2; GL2, 8 J/cm2; GL3, 12 J/cm2) and Endophoton KLD GaAs 904 nm (ST, 10 J/cm2) for 2 nonconsecutive days per week for 10 weeks, for a total of 20 sessions. The primary outcomes will be ulcer healing rate and University of Texas classification scores. Patients' DFUs will be assessed on the 1st day, 5 weeks, and 10 weeks of treatment then 1 month after the end of treatment. This study may aid effective clinical decision-making for the management of DFUs.

Effects of photobiomodulation on different phases of in vitro osteogenesis.

The present study aimed to evaluate the effect of photobiomodulation therapy (PBM) on different stages of osteogenesis in vitro. For this, osteoblastic-like cells (Saos-2 cell lineage) were irradiated in two different periods: during the Proliferation phase (PP; from the second to the fourth day) and during the Differentiation phase (DP; from the seventh to the ninth day). The energy density used in the study was 1.5 J/ cm2. The following parameters were evaluated: 1) quantification of collagen type 1 (COL 1), osteopontin (OPN), and bone morphogenetic protein 2 (BMP-2); 2) quantification of alkaline phosphatase (ALP) activity; and 3) quantification of  extracellular matrix (ECM) mineralization. Non-irradiated cultures were used as controls. The data were analyzed using the Student's t-test or one-way ANOVA, considering a significance level of 5%. The results indicated that COL 1 and BMP-2 quantification was higher in Saos-2 irradiated during the DP in relation to the control group at day 10 (p < 0.05). No differences were observed for other comparisons at this time point (p > 0.05). OPN expression was greater in PP compared with the other experimental groups at day 10 (p < 0.05). Irradiation did not affect ALP activity in Saos-2 regardless of the exposure phase and the time point evaluated (p > 0.05). At day 14, ECM mineralization was higher in Saos-2 cultures irradiated during the DP in relation to the PP (p < 0.05). In conclusion, the results suggested that the effects of PBM on osteoblastic cells may be influenced by the stage of cell differentiation.

Might photobiomodulation therapy interfere with the frequency of severe mucositis and oral candidiasis? A retrospective analysis in patients with head and neck carcinoma.

PURPOSE: Considering the tumor in the oral cavity or the oropharynx and nasopharynx region might be an aggravating factor for oral mucositis (OM) manifestation, the present study aimed to evaluate whether the location of the tumor and the use of photobiomodulation therapy (PBMT) might affect the frequency of oral candidiasis (OC) during radiotherapy (RT) and/or chemotherapy (CT) treatments. METHODS: The medial records of seventy-four patients with head and neck cancer treated in a public service from 2016 to 2019 were evaluated. All these patients were submitted to RT in an accumulated dose of 48 to 70 Gy of radiation. Data about OM and OC were collected and presented according to the application of a therapeutic protocol with laser photobiomodulation (PBMT) to control oral mucositis, or not (No-PBM), and the location of tumor (head and neck or oral cavity). In the PBMT group patients, a low-power laser device composed of InGaAlP diode (maximum output power of 86.7 mW, active tip area of 0.1256 cm2, and continuous wavelength of 660 nm), was applied to the lips (three points each), right and left jugal mucosa (three points each), the limit between hard and soft palate (three points), buccal floor/sublingual gland (one point), lateral edge of the tongue (three points on each side), and back of the tongue (six points), three times weekly, for 5 weeks. The dosimetry used in each application was 2 J for 3 s, thus totaling 56 J. The correlation between clinical characteristics such as age, tumor size (T), metastatic lymph node (N), number of RT and CT sessions, candidiasis, and OM were analyzed. RESULTS: Mucositis grades 1 and 2 were the most common among all patients, especially before the 12th radiotherapy session, regardless of the treatment with PBM (p > 0.05). Additionally, no difference in the grade of OM and OC was significantly observed when comparing the two laser therapy groups. OC was more frequent after the 12th radiotherapy session in all groups. Nonetheless, OM and OC had a different correlation regarding to tumor location (head and neck and oral cavity) being PBMT a positive therapy to delay OM. It was observed a positive and statistically significant correlation between tumors at oral cavity and OM, regardless PBMT (R = 0.84, p < 0.05 to PBMT and R = 0.13, p < 0.05 to No-PBM). Otherwise, OC was positively correlated to local metastasis in patients with oral tumors undergoing PBMT (R = 0.84, p < 0.05). CONCLUSION: Patients with oral cavity tumor presented more OM, especially high grades, then patients with tumors in other regions of the head and neck, which seems to be related to the irradiation parameters of radiotherapy and/or with the limitation of conduction of PBMT in tumor areas. OM and OC were not changed by PBMT, although it helped to reduce the incidence of severe cases of OM.

Photobiomodulation improves cell survival and death parameters in cardiomyocytes exposed to hypoxia/reoxygenation.

INTRODUCTION: Cardiovascular diseases are the leading cause of morbidity and mortality worldwide. Ischemic heart disease is one of the most harmful conditions to cellular structure and function. After reperfusion treatment, a spectrum of adverse effects becomes evident, encompassing altered cell viability, heightened oxidative stress, activated autophagy, and increased apoptosis. Photobiomodulation (PBM) has been utilized in experimental models of cardiac hypoxia to enhance mitochondrial response and ameliorate biochemical changes in injured tissue. However, the effects of PBM on cultured cardiomyocytes subjected to hypoxia/reoxygenation are not yet well established. METHOD: H9C2 cardiomyocytes were exposed to hypoxia with concentrations of 300 µM CoCl2 for 24 h, followed by 16 h of reoxygenation through incubation in a normoxic medium. Treatment was conducted using GaAIAs Laser (850 nm) after hypoxia at an intensity of 1 J/cm2. Cells were divided into three groups: Group CT (cells maintained under normoxic conditions), Group HR (cells maintained in hypoxia and reoxygenation conditions without treatment), Group HR + PBM (cells maintained in hypoxia and reoxygenation conditions that underwent PBM treatment). Cell viability was analyzed using MTT, and protein expression was assessed by western blot. One-way ANOVA with the Tukey post hoc test was used for data analysis. Differences were significant when p < 0.05. RESULTS: PBM at an intensity of 1 J/cm2 mitigated the alterations in cell survival caused by hypoxia/reoxygenation. Additionally, it significantly increased the expression of proteins Nrf2, HSP70, mTOR, LC3II, LC3II/I, and Caspase-9, while reducing the expression of PGC-1α, SOD2, xanthine oxidase, Beclin-1, LC3I, and Bax. CONCLUSION: PBM at intensities of 1 J/cm2 reverses the changes related to oxidative stress, mitochondrial biogenesis, autophagy, and apoptosis caused by hypoxia and reoxygenation in a culture of cardiomyocytes.

Efficacy of Photobiomodulation Therapy in Older Adults: A Systematic Review.

BACKGROUND: The aim was to determine whether there is any available evidence on the efficacy of photobiomodulation therapy (PBMT) in older adults. METHODS: A literature search was performed including all articles published up to February 2024. Studies reporting data on PBMT in older adults were included. This study was registered with PROSPERO. RESULTS: In total, 406 studies were identified. After eliminating duplicates and irrelevant studies, 10 records were included in the final review. In all included studies, the protocols used to deliver PBMT were different in terms of type of device, wavelength, irradiation duration, and pulse frequency. In neurodegenerative diseases, two studies reported non-significant results, while two studies reported efficacy of PBMT. In wounds and ulcers, two out of three studies reported efficacy of PBMT. In macular degeneration, one study reported efficacy of PBMT. One study on hyposalivation reported efficacy of PBMT. CONCLUSION: PBMT appears to be a promising complementary treatment. All studies reported good compliance and safety throughout the treatment. In the future, it will be essential to harmonize PBMT parameters. Further studies are warranted to define the best indications, the most effective protocols, and the right population to target for use in routine practice.

Effect of photobiomodulation in the balance between effector and regulatory T cells in an experimental model of COPD.

Introduction: Currently, Chronic Obstructive Pulmonary Disease (COPD) has a high impact on morbidity and mortality worldwide. The increase of CD4+, CD8+ cells expressing NF-κB, STAT4, IFN-γ and perforin are related to smoking habit, smoking history, airflow rate, obstruction and pulmonary emphysema. Furthermore, a deficiency in CD4+CD25+Foxp3+ regulatory T cells (Tregs) may impair the normal function of the immune system and lead to respiratory immune disease. On the other hand, the anti-inflammatory cytokine IL-10, produced by Treg cells and macrophages, inhibits the synthesis of several pro-inflammatory cytokines that are expressed in COPD. Therefore, immunotherapeutic strategies, such as Photobiomodulation (PBM), aim to regulate the levels of cytokines, chemokines and transcription factors in COPD. Consequently, the objective of this study was to evaluate CD4+STAT4 and CD4+CD25+Foxp3+ cells as well as the production of CD4+IFN- γ and CD4+CD25+IL-10 in the lung after PBM therapy in a COPD mice model. Methods: We induced COPD in C57BL/6 mice through an orotracheal application of cigarette smoke extract. PMB treatment was applied for the entire 7 weeks and Bronchoalveolar lavage (BAL) and lungs were collected to study production of IFN- γ and IL-10 in the lung. After the last administration with cigarette smoke extract (end of 7 weeks), 24 h later, the animals were euthanized. One-way ANOVA followed by NewmanKeuls test were used for statistical analysis with significance levels adjusted to 5% (p < 0.05). Results: This result showed that PBM improves COPD symptomatology, reducing the number of inflammatory cells (macrophages, neutrophils and lymphocytes), the levels of IFN-γ among others, and increased IL-10. We also observed a decrease of collagen, mucus, bronchoconstriction index, alveolar enlargement, CD4+, CD8+, CD4+STAT4+, and CD4+IFN-γ+ cells. In addition, in the treated group, we found an increase in CD4+CD25+Foxp3+ and CD4+IL-10+ T cells. Conclusion: This study suggests that PBM treatment could be applied as an immunotherapeutic strategy for COPD.

How long does the biological effect of a red light-emitting diode last on adipose-derived mesenchymal stem cells?

This research investigated the duration of the influence of red light-emitting diodes (LED, 630 nm; output power: 2452.5 mW; laser beam: 163.5 cm2; irradiance: 15 mW/cm2; radiant exposure: 4 J/cm2) on different periods after irradiation (6, 12, 24, 48, and 72 h) on adipose-derived mesenchymal stem cells' (AdMSCs) metabolism and paracrine factors. AdMSCs were irradiated three times every 48 h. Twenty-four hours after the last irradiation, there was a higher MTT absorbance, followed by a decrease after 48 h. The cells' secretome showed increased levels of IL-6 and VEGF after 12 and 24 h, but this was reversed after 48 h. Additionally, LED irradiation resulted in higher levels of nitrite and did not affect oxidative stress markers. LED irradiation had significant effects on AdMSCs after 24 h compared to other groups and its control group.

Photobiomodulation of Na,K-ATPase in native membrane fraction and reconstituted in DPPC:DPPE-liposome.

Studies focusing on how photobiomodulation (PBM) can affect the structure and function of proteins are scarce in the literature. Few previous studies have shown that the enzymatic activity of Na,K-ATPAse (NKA) can be photo-modulated. However, the variability of sample preparation and light irradiation wavelengths have not allowed for an unequivocal conclusion about the PBM of NKA. Here, we investigate minimal membrane models containing NKA, namely, native membrane fraction and DPPC:DPPE proteoliposome upon laser irradiation at wavelengths 532, 650, and 780 nm. Interestingly, we show that the PBM on the NKA enzymatic activity has a bell-shaped profile with a stimulation peak (~15% increase) at around 20 J.cm-2 and 6 J.cm-2 for the membrane-bound and the proteoliposome samples, respectively, and are practically wavelength independent. Further, by normalizing the enzymatic activity by the NKA enzyme concentration, we show that the PBM response is related to the protein amount with small influence due to protein's environment. The stimulation decays over time reaching the basal level around 6 h after the irradiation for the three lasers and both NKA samples. Our results demonstrate the potential of using low-level laser therapy to modulate NKA activity, which may have therapeutic implications and benefits.

Photobiomodulation minimizes taste changes during hematopoietic cell transplantation: A randomized clinical trial.

Prevention and treatment protocols for taste changes observed during hematopoietic cell transplantation (HCT) are not well-established. The purpose of this study was to assess the efficacy of photobiomodulation (PBM) in relieving taste changes and preventing lingual papillae atrophy. HCT patients received PBM (n = 42) on the tongue dorsum using an InGaAIP laser (660 nm, 100 mW, 1.1 W/cm2, 8.8 J/cm2). During the HCT conditioning (T0), severe neutropenia (T1), and after neutrophil engraftment (T2), taste acuity for sweet, bitter, sour, and salty solutions, and clinical appearance of lingual papillae were compared with those of a placebo group (n = 43). PBM significantly reduced hypogeusia, ageusia, and parageusia at T1 and T2, and also successfully prevented papillae atrophy during all the analyzed HCT periods. In conclusion, PBM enhanced taste acuity during HCT. The decrease in papillae atrophy indicated a potential regenerative effect of this therapy on tongue mucosa.

Effective Parameters for Orthodontic Tooth Movement Acceleration with Photobiomodulation: An Umbrella Review.

Objective: To answer this research question: What are the effective wavelength, power, and energy density parameters for achieving dental movement acceleration? Background Data: Photobiomodulation (PBM) has been clinically studied for its ability to accelerate dental movements in orthodontics. However, its effectiveness is dose dependent. Methods: The search was carried out in PubMed, SCOPUS, and ISI Web of Science. The quality of the included systematic reviews was performed using the AMSTAR 2 tool. The risk of bias was assessed using the ROBIS tool. Results: In total, 29 articles in PubMed, 75 in Scopus, and 61 in ISI Web of Science. Finally, only five systematic reviews were included. Conclusions: The results showed the range from 730 to 830 nm as the most effective range of wavelength to accelerate the orthodontic dental movement. A power range of 0.25-200 mW, with emphasis on the direct correlation between power, wavelength, and energy density. Energy density has not been adequately reported in the most randomized controlled clinical trials.

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.

Treatment of lingual nerve paresthesia through photobiomodulation therapy: a case report employing an approach integrating extraoral and intraoral modalities

Aims: Oral nerve injuries are the primary cause of paresthesia in the head and neck regions. To report the managing of a combined protocol involving extraoral and intraoral photobiomodulation (PBM) therapy for lingual nerve paresthesia. Case report: A 38-year-old female patient underwent 25 PBM sessions using laser with dual wavelength infrared (810nm + 980 nm). The extraoral application included 6 seconds and 6J per point. per point, 1W, 4.91 cm², 1.2 J/cm. The intraoral protocol with 0.3W of power, a spot size of 0.38 cm², 15.78 J/cm² of energy density, 6J of energy per point, for 20 seconds. Results: Assessment of neurosensitivity on the dorsum of the tongue was a 75% improvement. On the lateral tongue improved to 50%. In the floor of the mouth, PBM demonstrated a 25% improvement. Conclusion: PBM is an important treatment option in the case of lingual nerve paresthesia. The use of PBM should be considered as a feasible, non-invasive treatment approach.

Does photobiomodulation alter mitochondrial dynamics?

Mitochondrial dysfunction is one of the leading causes of disease development. Dysfunctional mitochondria limit energy production, increase reactive oxygen species generation, and trigger apoptotic signals. Photobiomodulation is a noninvasive, nonthermal technique involving the application of monochromatic light with low energy density, inducing non-thermal photochemical effects at the cellular level, and it has been used due to its therapeutic potential. This review focuses on the mitochondrial dynamic's role in various diseases, evaluating the possible therapeutic role of low-power lasers (LPL) and light-emitting diodes (LED). Studies increasingly support that mitochondrial dysfunction is correlated with severe neurodegenerative diseases such as Parkinson's, Huntington's, Alzheimer's, and Charcot-Marie-Tooth diseases. Furthermore, a disturbance in mitofusin activity is also associated with metabolic disorders, including obesity and type 2 diabetes. The effects of PBM on mitochondrial dynamics have been observed in cells using a human fibroblast cell line and in vivo models of brain injury, diabetes, spinal cord injury, Alzheimer's disease, and skin injury. Thus, new therapies aiming to improve mitochondrial dynamics are clinically relevant. Several studies have demonstrated that LPL and LED can be important therapies to improve health conditions when there is dysfunction in mitochondrial dynamics.