An SEM study on the effect of 9.3-µm CO2 laser on dentinal tubules for hypersensitivity treatment.

OBJECTIVES: In-vitro studies were performed on dentin of extracted human molars to investigate the effectiveness of 9.3 µm CO2 laser irradiation to occlude dentinal tubules. The observed occlusion of dentinal tubules with the irradiation was compared with application of three reagents: 2% Sodium Fluoride gel, an aqueous solution of hydroxyapatite nanoparticles and an equal mix of the two. We show that 9.3 µm CO2 laser irradiation occludes dentinal tubules, and the use of laser irradiation produces better occlusion of the opened tubules compared to the use of topical reagents. METHODS: Nine extracted and cleaned human molars were cut to obtain dentin disks of thickness of 3-5 mm. Each disc was divided into four quarters, and each quarter served as two samples corresponding to irradiated and non-irradiated group counterparts. Five disks were used to study the effect of various laser irradiation energies on the dentinal tubules to find a good pulse fluence for occlusion of the dentinal tubules, and four disks were used for studying the effects of reagents and irradiation at the pulse fluences found in the first part of the study. The samples were irradiated with a beam diameter of 1 mm (1/e2) at 15 Hz pulse repetition rate, scanned automatically using a set of scanning mirrors. Samples were imaged using Scanning Electron Microscope (SEM) which were processed to determine tubule diameter. Safety of the irradiation treatment was investigated on 6 samples by measuring pulpal temperature rise. The effect of three topical reagents corresponding to 2% Sodium Fluoride gel (F), Hydroxyapatite nanoparticles (HA) and an equal mix of F and HA (HAF) on dentinal tubule occlusion was evaluated and compared with the laser irradiation. RESULTS: In all examined cases, laser irradiation at a fluence of 0.81 J/cm2 resulted in a temperature increase less than 3 °C which is safe, and no surface cracking was observed. There is a threshold pulse fluence of 0.27 J/cm2 above which, laser produced surface melting. At a pulse fluence of 0.81 J/cm2 a layer of recast of melted dentin was formed. Under this layer, peritubular dentin melting and occluding of the dentinal tubules was observed. Application of either F or HA or HAF did not produce visible occlusion effect on open tubules after washing and microbrushing with excess distilled water. CONCLUSIONS: 9.3 µm CO2 laser irradiation on extracted human molar dentin at pulse fluence of 0.81 J./cm2 resulted in tubule area reduction by 97% without rising pulpal temperatures to unsafe levels.

Photobiomodulation therapy for chronic knee pain in obese patients in pre-rehabilitation for bariatric surgery: randomised, placebo-controlled, double-blinded, clinical trial protocol.

INTRODUCTION: Obesity has become a worldwide public health problem and is directly linked to loss of quality of life, complications and comorbidities. One of them is chronic pain, especially in the knees, which increases significantly and proportionally with weight gain. In patients with severe obesity, with indication for bariatric surgery, the presence of chronic pain disables and often prevents their participation in a pre-surgical rehabilitation programme. As an analgesic therapy, photobiomodulation (PBM) has been studied with safety, efficacy, well-tolerated used and low costs. Thus, this study aims to evaluate the use of PBM for the treatment of chronic knee pain in obese patients undergoing a pre-surgical rehabilitation programme for bariatric surgery. METHODS AND ANALYSES: This is a double-blinded, randomised, placebo-controlled clinical, superiority, trial protocol. The PBM will be applied in bilateral knees and lumbar paraspinal points levels referring to the roots of innervation of the knee. The outcomes evaluated will be pain intensity, functionality, quality of life and clinical signs of neurological sensitization of chronic knee pain pathways. ETHICS AND DISSEMINATION: This protocol has already been approved by the Comitê de Ética em Pesquisa do Hospital das Clínicas da Universidade Federal de Goiás/EBSERH-Ethics Committee and it is following SPIRIT guidelines. The results will be statistically analysed and subsequently published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: Clinical Trials Platform (https://clinicaltrials.gov/) with the number NCT05816798.

Regenerative Potential of Dental Pulp Stem Cells in Response to a Bioceramic Dental Sealer and Photobiomodulation: An In Vitro Study.

AIMS: This study aims to assess the synergistic effect of utilizing a bioceramic sealer, NeoPutty, with photobiomodulation (PBM) on dental pulp stem cells (DPSCs) for odontogenesis. MATERIALS AND METHODS: Dental pulp stem cells were collected from 10 premolars extracted from healthy individuals. Dental pulp stem cells were characterized using an inverted-phase microscope to detect cell shape and flow cytometry to detect stem cell-specific surface antigens. Three experimental groups were examined: the NP group, the PBM group, and the combined NP and PBM group. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) experiment was conducted to assess the viability of DPSCs. The odontogenic differentiation potential was analyzed using Alizarin red staining, RT-qPCR analysis of odontogenic genes DMP-1, DSPP, and alkaline phosphatase (ALP), and western blot analysis for detecting BMP-2 and RUNX-2 protein expression. An analysis of variance (ANOVA) followed by a post hoc t-test was employed to examine and compare the mean values of the results. RESULTS: The study showed a notable rise in cell viability when NP and PBM were used together. Odontogenic gene expression and the protein expression of BMP-2 and RUNX-2 were notably increased in the combined group. The combined effect of NeoPutty and PBM was significant in enhancing the odontogenic differentiation capability of DPSCs. CONCLUSION: The synergistic effect of NeoPutty and PBM produced the most positive effect on the cytocompatibility and odontogenic differentiation potential of DPSCs. CLINICAL SIGNIFICANCE: Creating innovative regenerative treatments to efficiently and durably repair injured dental tissues. How to cite this article: Alshawkani HA, Mansy M, Al Ankily M, et al. Regenerative Potential of Dental Pulp Stem Cells in Response to a Bioceramic Dental Sealer and Photobiomodulation: An In Vitro Study. J Contemp Dent Pract 2024;25(4):313-319.

The effect of photobiomodulation on histamine and Mucuna pruriens-induced pruritus, hyperknesis and alloknesis in healthy volunteers: A double-blind, randomized, sham-controlled study.

BACKGROUND: Photobiomodulation, also referred to as Low-Level Light Therapy (LLLT), has emerged as a promising intervention for pruritus, a prevalent and often distressing symptom. OBJECTIVES: This study investigated the efficacy of low-level light therapy (LLLT) in alleviating pruritus, hyperknesis, and alloknesis induced by histamine and Mucuna pruriens. METHODS: In a double-blind, randomized, sham-controlled trial with a split-body design, healthy volunteers underwent 6 minutes of LLLT and sham treatments in separate upper back quadrants. The histamine model was applied to the upper quadrants, and Mucuna pruriens to the lower quadrants. Pruritus intensity, alloknesis, hyperknesis, flare area, and skin temperature were measured pre and post treatment. RESULTS: Seventeen individuals (eight females, nine males) participated in the study. In the histamine model, LLLT notably reduced itch intensity (difference = 13.9 (95% CI: 10.5 - 17.4), p = 0.001), alloknesis (difference = 0.80 (95% CI: 0.58-1.02), p = 0.001), and hyperknesis (difference = 0.48 (95% CI: 0.09-0.86), p = 0.01). Skin temperature changes were not significantly different between the two groups (difference = -2.0 (95% CI: -6.7-2.6), p = 0.37). For the Mucuna pruriens model, no significant differences were observed in any measures, including itch intensity (difference = 0.8 (95% CI: -2.3 - 3.8), p = 0.61) hyperknesis (difference = 0.08 (95% CI: -0.06-0.33), p = 0.16) and alloknesis (difference = 0. 0.09 (95% CI: -0.08-0.256), p = 0.27). CONCLUSIONS: LLLT effectively reduced histamine-induced pruritus, alloknesis, and hyperknesis; however, LLLT was ineffective against Mucuna pruriens-induced pruritus. Further investigations are required to determine LLLT's effectiveness of LLLT in various pruritus models.

Could Photobiomodulation help lactating women and their newborns?

During the first several weeks following lactation, nipple pain frequently prevents mothers from continuing breastfeeding. To evaluate the efficacy of using Photobiomodulation (PBM) versus anti-inflammatory topical cream, on inflamed nipple, and the effect on milk production. This study was carried-out on 50 breastfeeding women with nipple pain and fissure. Our patients were divided into two groups ; study group (Group I): 25 patients received 12 sessions of PBM using Diode laser for a period of 4 weeks, 3 sessions per week every alternative day, and controlled group (Group II): 25 patients used Anti-inflammatory topical cream. Regarding inflammatory signs in both groups, Group I showed a significant decrease in redness compared to Group II at the 3rd and 4th week, and a significant decrease in nipple fissure and pain at the 3rd week. There was a significant increase in milk amount reflected on the infant's weight. We concluded that PBM was more effective in decreasing nipple pain, inflammation and subsequently milk production and infant weight than topical anti-inflammatory creams.

Antiproliferative effect of low-level laser/ photobiomodulation on gingival fibroblasts derived from calcium channel blocker-induced gingival overgrowth.

The aim of this study was to evaluate the antiproliferative properties of low-level laser therapy (LLLT) on gingival fibroblasts obtained from calcium channel blocker-induced gingival overgrowth (GO). Gingival fibroblasts of patients with GO were compared to healthy gingival fibroblasts (H). Both cells were exposed to LLLT (685 nm wavelength, 25mW power, diode laser) and compared to those not treated with LLLT. Cell proliferation and viability were measured with MTT assay at baseline and after 24 and 72 h. TGF-ß1, CTGF, and collagen Type 1 levels were evaluated with Enzyme-Linked Immunosorbent Assay (ELISA). LLLT significantly decreased the proliferation of GO fibroblasts (p < 0.05) while leading to a significantly higher proliferation in H fibroblasts compared to the untreated cells (p < 0.05). GO cells showed significantly higher CTGF, TGF-ß, and collagen Type 1 expression than the H cells (p < 0.05). LLLT significantly reduced CTGF levels in GO cells compared to the control group (p < 0.05). In H cells, CTGF and TGF-ß levels were also significantly decreased in response to LLLT compared to the control group (p < 0.05). While LLLT significantly reduced collagen expression in the H group (p < 0.05), it did not significantly impact the GO cells. LLLT significantly reduced the synthesis of the growth factors and collagen in both groups with an antiproliferative effect on the gingival fibroblasts from calcium channel blocker-induced GO, suggesting that it can offer a therapeutic approach in the clinical management of drug-induced GO, reversing the fibrotic changes.

Effectiveness of low-level laser therapy in reducing pain score and healing time of recurrent aphthous stomatitis: a systematic review and meta-analysis.

BACKGROUND: Recurrent aphthous stomatitis (RAS) is a common chronic inflammatory oral disease that negatively impacts the quality of life. Current therapies aim to reduce pain and healing process yet challenges such as rapid loss due to salivary flushing in topical drugs and adverse effects due to prolonged use of systemic medications require further notice. Low-level laser therapy is reported with immediate pain relief and faster healing thus preserving the potential for optimal treatment modalities. This review critically analyses and summarizes the effectiveness of LLLT in reducing pain scores and healing time of RAS. METHODS: A systematic search was conducted in ScienceDirect, PubMed, and Scopus using keywords of low-level laser therapy, photo-biomodulation therapy, and recurrent aphthous stomatitis. RCTs between 1967 to June 2022, presenting characteristics of the laser and reporting pain score and/or healing time of RAS after irradiation were included. Animal studies and recurrent aphthous ulcers with a history of systemic conditions were excluded. Studies were critically appraised using the RoB 2 tool. A meta-analysis was performed using inverse variance random effects. RESULTS: Fourteen trials with a total of 664 patients were included. Reduced pain was reported in 13 studies, while shortened healing time was presented in 4. The pooling of two studies after CO2 irradiation demonstrated faster healing time compared to placebo (MD - 3.72; 95% CI - 4.18, - 3.25). CONCLUSION: Pain score and healing time of RAS were reduced after irradiation with LLLT. RoB resulted in "some concerns" urging well-designed RCTs with larger samples to further assess each laser application for comparison. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42022355737.

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.

Fractional picosecond laser treatment of non-acne atrophic scars and scar erythema in Chinese patients.

BACKGROUND: Fractional picosecond lasers (FPL) are reported to be effective and safe for atrophic acne scars and post-acne erythema. However, there is no evidence regarding the effectiveness and safety of FPL treatment for non-acne atrophic scars and scar erythema among Chinese patients. METHODS: In this retrospective study, 12 Chinese patients with non-acne atrophic scars, including nine with scar erythema, were treated with one to three sessions of 1064 nm FPL treatment. Clinical improvement was objectively assessed through blinded evaluations by external physicians. A modified Manchester Scar Scale (mMSS) and the Clinician Erythema Assessment Scale (CEAS) were individually used to evaluate atrophic scars and scar erythema based on photographs. Physician-assessed and subject-assessed Global Aesthetic Improvement Scale (GAIS) were used to assess changes before and after FPL treatment. Patient satisfaction and adverse events were also documented. RESULTS: Total mMSS scores, as well as three parameters (color, distortion, and texture), were significantly decreased after FPL treatment, with a mean reduction of 3.18 ± 1.60 in total scores (p < 0.05). The CEAS scores were significantly reduced from 2.41 ± 0.98 before treatment to 0.41 ± 0.40 at the final visit (p < 0.05). Based on physician-assessed and subject-assessed GAIS scores, 11 (91.7%) patients were improved after FPL treatment. 33.3% of patients were very satisfied, and 41.7% were satisfied. No serious, prolonged (> 3 weeks) adverse events were observed. CONCLUSION: Our study suggests that 1064 nm FPL treatment may be a promising option for non-acne atrophic scars, especially with scar erythema. Further studies are needed to confirm our results.

Effects of photobiomodulation and an aerobic exercise on the level of pain and quality of life in women with fibromyalgia.

To evaluate the effectiveness of photobiomodulation (PBM) in conjunction with an aerobic exercise program (AEP) on the level of pain and quality of life of women with fibromyalgia (FM). METHODS: A double-blinded randomized controlled trial in which 51 participants with FM were allocated into 4 groups: control group (CG) (n = 12); active PBM group (APG) (n = 12); AEP and placebo PBM group (EPPG) (n = 13); AEP and active PBM group (EAPG) (n = 14). AEP was performed on an ergometric bicycle; and a PBM (with an increase dosage regime) [20 J, 32 J and 40 J] was applied using a cluster device. Both interventions were performed twice a week for 12 weeks. A mixed generalized model analysis was performed, evaluating the time (initial and final) and group (EAPG, EPPG, APG and CG) interaction. All analyses were based on intent-to-treat for a significance level of p ≤ 0.05. RESULTS: The intra-group analysis demonstrated that all treated groups presented a significant improvement in the level of pain and quality of life comparing the initial and final evaluation (p < 0.05). Values for SF-36 and 6-minute walk test increased significant in intragroup analysis for EPPG comparing the initial and final evaluation. No intergroup differences were observed. CONCLUSIONS: Both exercised and PBM irradiated volunteers present improvements in the variables analyzed. However, further studies should be performed, with other PBM parameters to determine the best regime of irradiation to optimize the positive effects of physical exercises in FM patients.

Adherence to Self-care and Quality of Life of Patients with Diabetic Foot Ulcers Treated with Low-Level Laser Therapy: An Exploratory Study.

OBJECTIVE: To evaluate the quality of life (QoL) of patients with a diabetic foot ulcer undergoing treatment with low-level laser therapy (LLLT) at 904 nm and its association with self-care. METHODS: In this randomized, exploratory study, participants were divided into the following four groups: control group (CG) with LLLT placebo, LLLT group 1 (LG1) at 10 J/cm2, LLLT group 2 (LG2) at 8 J/cm2, and LLLT group 3 (LG3) at 4 J/cm2. Participants received light therapy (or placebo) twice a week, for a total of 20 sessions. Researchers assessed participants' QoL using the Short-Form 36 questionnaire. RESULTS: Sixty-two participants were included in the analysis (CG = 18, LG1 = 14, LG2 = 17, LG3 = 13). The LG1 group showed a higher proportion of healing, whereas the CG group showed a lower proportion than the other groups. The LG1 group showed a relationship between physical limitations and blood glucose monitoring, pain and foot care, and general health status (GHS) and foot care. The GL2 group showed a relationship between physical limitations and blood glucose monitoring, vitality and foot care, and GHS and diet. CONCLUSIONS: Low-level laser therapy had a positive impact on QoL as assessed by the Short-Form 36 questionnaire (functional capacity, vitality, and pain domains), and there was a positive association between QoL and self-care in the LLLT groups (physical limitations, pain, GHS, and vitality domains).

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.

High-frequency low-intensity semiconductor laser irradiation enhances osteogenic differentiation of human cementoblast lineage cells.

PURPOSE: Laser irradiation activates a range of cellular processes in the periodontal components and promotes tissue repair. However, its effect on osteogenic differentiation of human cementoblast lineage cells remains unclear. This study aimed to examine the effects of high-frequency semiconductor laser irradiation on the osteogenic differentiation of human cementoblast lineage (HCEM) cells. METHODS: HCEM cells were cultured to reach 80% confluence and irradiated with a gallium-aluminum-arsenide (Ga-Al-As) semiconductor laser with a pulse width of 200 ns and wavelength of 910 at a dose of 0-2.0 J/cm2. The outcomes were assessed by analyzing the mRNA levels of alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX2), and type I collagen (COLL1) using real-time polymerase chain reaction (PCR) analysis 24 h after laser irradiation. Cell mineralization was evaluated using ALP activity, calcium deposition, and Alizarin Red staining. RESULTS: The laser-irradiated HCEM cells showed significantly enhanced gene expression levels of ALP, RUNX2, and COLL1 as well as ALP activity and calcium concentration in the culture medium compared with the non-irradiated cells. In addition, enhanced calcification deposits were confirmed in the laser-irradiated group compared with the non-irradiated group at 21 and 28 days after the induction of osteogenic differentiation. CONCLUSION: High-frequency semiconductor laser irradiation enhances the osteogenic differentiation potential of cultured HCEM cells, underscoring its potential utility for periodontal tissue regeneration.

Impact of Photobiomodulation on IL1ß and TGFß-1 concentrations in patients with aphthous stomatitis.

Laser therapy has shown effectiveness in promoting wound healing by influencing various physiological factors such as blood flow, cytokines, histamine, nerve signals, lymphocyte function, tissue oxygenation, and cell growth. This study aims to evaluate the therapeutic efficacy of Photobiomodulation (PBM) treatment, by using diode laser, in modifying the levels of interleukin-1 beta (IL1ß) and transforming growth factor beta-1 (TGFß-1) in patients diagnosed with aphthous stomatitis. A before-after interventional design was conducted over 10 months with 20 subjects. Data on demographic details and serum concentrations of IL1ß and TGFß-1 were collected pre-treatment and on Days 3 and 7 post-treatments. The intervention involved a single session of four 30-second applications of a QuickLase dual-wavelength laser operating at 980 nm. Results show significant reductions in IL1ß and TGFß-1 levels after 7 days of treatment, indicating a time-dependent effect of PBM therapy on these inflammatory markers. The findings suggest that PBM therapy holds promise as an intervention for reducing inflammation associated with aphthous stomatitis.

Evaluation of the effectiveness of picosecond KTP and fractional thulium lasers on pigmented-type periorbital dark circles.

OBJECTIVE: To determine the effectiveness of picosecond KTP in reducing peri-ocular dark circles caused mainly by excessive pigmentation and to compare Picosecond KTP with Thulium laser ability in reducing the intensity and extent of peri-ocular dark circles. MATERIALS AND METHODS: This split-face prospective study included twelve women with periorbital dark circles (pigmented or mixed-pigmented type). The left lower eyelid was treated using the PicoHi machine (HIRONIC Ltd), a full beam Q-switched Nd-YAG provided by KTP crystal (523 nm) at settings of 0.3 J/cm2, 5 mm, 5 Hz, and 300 Ps. Whereas the right lower eyelid was treated using the Lavieen machine (WON TECH Co., Ltd), a fractional Thulium laser (1927 nm) at setting 1320 mJ/cm2, 30 × 15 mm, 1500 microseconds. Patients received a series of 3 treatment sessions, given at 4-week intervals. RESULTS: The 532-nm full beam Q-switched KTP and fractional Thulium lasers were more likely to induce post-inflammatory hyperpigmentation rather than decrease the pigmentation. The risk is higher with a Q-switched KTP laser, which may be attributed to the skin tone of the participants. Nonetheless, some improvement in the pigmented type of PDCs, although not detected clinically, was documented by the VISIA software. CONCLUSION: No solid conclusion can be drawn from the results of the study. Picosecond KTP and Thulium lasers may have a role in reducing PDCs yet more studies should be performed in order to determine the exact impact these lasers have.

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.

High-intensity versus low-level laser in musculoskeletal disorders.

PURPOSE: To evaluate the current evidence comparing low level to high level laser therapy to reveal any superiorities in the treatment of musculoskeletal disorders. METHODS: Five databases were searched till September 2022 to obtain relevant RCTs comparing high intensity and low-level laser therapies in the management of musculoskeletal disorders. Two authors assessed the methodological quality of the included studies using the Physiotherapy Evidence Database scale and meta-analysis was conducted for studies that showed homogeneity. RESULTS: Twelve articles were included in this systematic review with a total population of 704 participants across various musculoskeletal pathologies including tennis elbow, carpal tunnel syndrome, chronic non-specific low back pain, knee arthritis, plantar fasciitis, and subacromial impingement. There were no statistical differences between the two interventions in pain, electrophysiological parameters, level of disability, quality of life, postural sway or pressure algometer, however, Low level laser therapy showed superiority in increasing grip strength compared to high intensity laser therapy while results were significant in favour of high intensity laser therapy regarding long head of biceps diameter and cross sectional area, supraspinatus thickness and echogenicity and acromio-humeral distance. CONCLUSION: The current literature suggests no superiority of both types of laser therapy in musculoskeletal disorders, however, more RCTs with larger sample size are required to reach a definitive conclusion regarding the superiority of either form of laser therapy in musculoskeletal disorders.

Activation of reparative processes of chronic wounds using photobiomodulation therapy (experimental study).

OBJECTIVE: Aim: The aim of the work was to study the ef f ect of photobiomodulation therapy on the regulation of disorders in the healing of chronic wounds at the remodeling stage using indicators of platelet aggregation activity, reactive oxygen species, platelet-derived growth factor, and interleukin-1ß. PATIENTS AND METHODS: Materials and Methods: The study included 3 groups of Wistar rats: intact animals and animals of the control and experimental groups, for which chronic wounds were simulated. Rats in the experimental group received photobiomodulation therapy once a day for 5 days. Wound defects of animals in the control group were fictitiously irradiated. The levels of reactive oxygen species, platelet-derived growth factor, and interleukin-1ß in the blood serum of animals were studied by enzyme immunoassay. The functional activity of platelets was measured on a computerized platelet aggregation analyzer using the turbidimetric method. Histological studies were carried out. RESULTS: Results: Changes in the expression of the studied indicators were found in the blood serum of animals with chronic wounds when using photobiomodulation therapy: an increase in platelet-derived growth factor concentrations, the levels of reactive oxygen species and interleukin-1ß did not have statistically signif i cant differences compared to the corresponding indicators of animals in the control group. There were no significant differences in the indicators of platelet aggregation activity in the control and experimental groups of animals. CONCLUSION: Conclusions: The findings suggest that photobiomodulation therapy may promote wound healing by increasing platelet-derived growth factor levels. Histological studies have shown that using photobiomodulation therapy helps reduce inflammation and better organization of collagen fibers in animals of the experimental group.

Photobiomodulation under Electroencephalographic Controls of Sleep for Stimulation of Lymphatic Removal of Toxins from Mouse Brain.

The meningeal lymphatic vessels (MLVs) play an important role in the removal of toxins from the brain. The development of innovative technologies for the stimulation of MLV functions is a promising direction in the progress of the treatment of various brain diseases associated with MLV abnormalities, including Alzheimer's and Parkinson's diseases, brain tumors, traumatic brain injuries, and intracranial hemorrhages. Sleep is a natural state when the brain's drainage processes are most active. Therefore, stimulation of the brain's drainage and MLVs during sleep may have the most pronounced therapeutic effects. However, such commercial technologies do not currently exist. This study presents a new portable technology of transcranial photobiomodulation (tPBM) under electroencephalographic (EEG) control of sleep designed to photo-stimulate removal of toxins (e.g., soluble amyloid beta (Aß)) from the brain of aged BALB/c mice with the ability to compare the therapeutic effectiveness of different optical resources. The technology can be used in the natural condition of a home cage without anesthesia, maintaining the motor activity of mice. These data open up new prospects for developing non-invasive and clinically promising photo-technologies for the correction of age-related changes in the MLV functions and brain's drainage processes and for effectively cleansing brain tissues from metabolites and toxins. This technology is intended both for preclinical studies of the functions of the sleeping brain and for developing clinically relevant treatments for sleep-related brain diseases.

Experimental study on the safety of photobiologic regulation therapy in the treatment of some non-epidermal tumors.

This study investigates the impact of Photobiomodulation (PBM) at different wavelengths on non-superficial cancer cells. Utilizing three laser protocols (650 nm, 810 nm, and 915 nm), the research explores cytotoxic effects, ROS generation, and cell migration. Results reveal varied responses across cell lines, with 810 nm PBM inducing significant ROS levels and inhibiting PAN-1 cell migration. The study suggests potential therapeutic applications for PBM in non-superficial cancers, emphasizing the need for further exploration in clinical settings.