There is strong evidence supporting the effectiveness of photobiomodulation therapy (PBMT) in improving neuronal damage and enhancing neuropsychological activities. However, there is limited research on the effects of this method on cognitive function and mood disorders. This project aimed to evaluate the potential benefits of PBMT in improving cognitive status and mood disorders in patients with dementia. In this randomized, double-blinded, controlled trial, 30 patients with mild-to-moderate dementia participated. The patients were divided into two groups: the first group ( = 15) received standard treatment along with PBMT, whereas the second group ( = 15) received standard treatment along with the use of an off-device on the head. Cognitive function, anxiety, and depression levels were assessed before, immediately after treatment, and 1 month later. The comparison of cognitive functional score at baseline, after completing the therapeutic regimen, as well as one later showed no difference between the two groups (Table 1). Similarly, the two groups had similar mean scores for depression and anxiety at baseline and after treatment interventions. [Table: see text] The treatment likely has no significant impact on improving cognitive status or mood disorders in patients with mild-to-moderate dementia.

This study reports an adaptive experience of pigmented scar treatment management with different characteristics. It is complicated to define a single solution for all the patients. For this reason, we report a multi-modal approach combining CO laser, Q-switched lasers (QSL), and dye laser to adapt to every different patient clinical situation. Thirty patients were enrolled to treat pigmented scars. Twenty patients presented scars with exogenous pigment (such as traumatic tattoos) and 10 with endogenous pigment (hyperpigmentation cases). A combination of CO laser, QSL, and dye laser was used. The number of treatment sessions performed for each laser, or their combination was as follow: For keloid scars from tattoo: 1-4 combined treatment sessions with QS and dye lasers; 3-4 combined treatment sessions with dye and CO laser;1-4 treatment sessions with QS followed by dye laser; for asphalt traumatic tattoo: 2-3 treatment sessions with QS; for surgical hypertrophic scars: 2-3 combined treatment sessions of QS and CO laser; for burn scars (due to asphalt contact) and hyperpigmentation: one treatment session with QS followed by CO laser. Six months after the final treatment, the patient's scar improvement was evaluated compared with baseline (T0) using a five-point Global Aesthetic Improvement Scale (GAIS). Regardless of the type of lesion and treatment, the whole population of the study showed satisfactory clinical results. The GAIS mean value was 3.3 ± 0.6. Specifically, 47% of the patients reported good results while 43% had excellent ones. No serious side effects were observed. Our results suggest that a combination of CO, dye, and Nd:YAG lasers is a feasible strategy for treating scars, reducing the pigmentary, fibrotic, and vascular components.

Green light photobiomodulation (GPBM, 500-565 nm) promotes tissue healing, reduces inflammation, and alleviates pain, with emerging potential in bone repair. This review evaluates GPBM's therapeutic effects on bone-related cells (proliferation, differentiation, migration), inflammation, vascularization, and neuronal responses. We assessed the influence of different GPBM parameters, possible underlying molecular mechanisms, and prospects for in vivo applications based on available studies. GPBM acts through mitochondria, opsins, and transient receptor potential vanilloid (TRPV) channels. The most effective irradiation method uses low irradiance (5.3-100 mW/cm) with a single exposure of ∼5 J/cm. Excessively low irradiance is ineffective, while excessively high irradiance may cause inhibitory effects. GPBM enhances bone-related cell functions, suppresses inflammation, and promotes vascular and neuronal responses. GPBM shows promise for bone repair, but further research is needed to optimize parameters, clarify molecular mechanisms, and standardize clinical trial protocols to ensure reliable in vivo outcomes.

Laser-assisted irrigation may enhance chemomechanical debridement and improve the sealing of root canals during endodontic treatment. This study aimed to address the scientific deficit in understanding the laser-assisted sequential versus continuous chelation in root canal irrigation. One hundred and twenty single-rooted teeth were prepared using Reciproc R40 instruments and randomly divided into six groups ( = 20) based on the irrigation protocol. In the sequential chelation groups, canals were irrigated with NaOCl during instrumentation, followed by 17% ethylenediaminetetraacetic acid using a needle, ultrasound, or erbium-doped yttrium aluminum garnet laser activation. In the continuous chelation groups, canals were irrigated with a mixture of 2% sodium hypochlorite and 9% hydroxyethylidene diphosphonic acid during and after instrumentation, followed by final activation using the same three techniques. Ten samples per group were used to evaluate sealer penetration with Fluo-3 dye, while the remaining samples underwent push-out bond strength testing. Statistical analyses were conducted using the Kruskal-Wallis and Friedman tests ( < 0.05). No significant differences in sealer penetration were found between sequential and continuous protocols in the apical third when needle or ultrasonic activation was used. However, laser activation combined with continuous chelation resulted in significantly higher sealer penetration and bond strength ( < 0.001). Sealer penetration followed the trend: coronal > middle > apical ( < 0.05) with all irrigation techniques. Continuous chelation protocols, especially when combined with laser activation, were as effective or superior to conventional methods in improving sealer penetration and bond strength. Continuous chelation with laser-assisted irrigation may improve clinical efficiency and shorten treatment time in root canal procedures.

Keloids and hypertrophic scars appear more frequently in people with darker skin tones, such as those of African, Asian, or Hispanic descent. The combination of CO laser, pulsed dye laser (PDL), and triamcinolone was successful in treating a keloid. The purpose of this research was to assess the clinical efficacy of a multi-modal treatment protocol comprising a 595 nm PDL, fractional ablative CO laser, 1540 nm nonablative laser, and intralesional corticosteroid injections for keloid management in Indian patients. A total of 30 patients with keloids were treated with a combination of two different lasers (595 nm pulsed/10,600 nm and 1540 nm fractional laser) and intralesional steroids injections. Clinical images were collected before treatment and at 9 months after the last treatment, and adverse effects were monitored throughout the study. Patients were assessed with the Detroit Keloid Scale before treatment and at follow-up. After completing treatments, almost all patients showed improvement; in particular, a decrease in redness was noted, and the keloids appeared flatter. This improvement was also recorded through the Detroit Keloid Scale, where a significant 6-point decrease on the scale was recorded between baseline and follow-up ( < 0.01). This combined therapy is a good option for people with darker skin tones since it has been proven as an effective tool for managing keloid, especially for enhancing texture and decreasing redness with a lower risk of postinflammatory hyperpigmentation.

The combination of lasers and acoustic shock waves has shown promising results in accelerating tattoo removal. To assess the effectiveness of treatments combining lasers and shock waves regarding the number of sessions required for successful tattoo removal. A prospective, observational, real-world, single-center study including adults (>18 years) with ≥one professional tattoo of any color on any body part, excluding the head, partially removed or not. Devices were the QS laser RevLite® SI (Cynosure Lutronic, USA), the picosecond laser PicoWay® (Candela, USA), the CO laser DUOGlide® with a SCAR 3 scanner (DEKA M.E.L.A. srl, Italy), and the GENTLE Pro® shock waves system (Zimmer MedizinSysteme GmbH, Germany). Treatment protocols consisted of QS/picosecond laser passes alternated with shock wave passes (three each) (classic protocol) and one QS/picosecond laser and one shock wave pass, a QS/picosecond second laser pass, and a final fractional CO laser pass (reinforced protocol). Sessions were performed at two-month intervals. We included 22 patients (68.2% women and 68.2% Fitzpatrick phototype III) with a mean (range) age of 42 (22-68) years and 25 tattoos in total. Most tattoos were black (92.0%) and were removed using the picosecond laser (80.0%) and following the classic (40.0%) and the reinforced (60.0%) protocols in a total of 66 treatment sessions. In 22 tattoos undergoing more than one session, results were good or excellent in 68.2% of them after 2-4 sessions, with no adverse effects. Acoustic shock wave therapy constitutes a safe adjuvant treatment to accelerate laser-based tattoo removal.

Prolonged soft tissue anesthesia (STA) after dental treatments in children poses a risk of soft tissue injury (STI). This study aimed to systematically review the role of photobiomodulation therapy (PBMT) in reducing the duration of STA and incidence of STI after dental procedures. This systematic review was performed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PROSPERO registration code: CRD42024622981). Five eligible studies were included, involving 32-60 participants between 4 and 10 years, utilizing a diode laser with various wavelengths (635, 660, 808, and 810 nm), energy densities (6-11.5 J/cm), irradiation times (12-30 sec), and irradiation points (6-12). The results demonstrated a significant reduction in duration of STA in all studies ( < 0.05); however, the reduction in the incidence of STI remained inconclusive. PBMT may serve as a painless and acceptable method to reduce the duration of STA in pediatric dentistry; however, its positive role in preventing STI remains inconclusive in patients with normal intellectual abilities supervised by alert caregivers.

This split-mouth randomized study evaluated the effect of in-office tooth whitening with violet Light-Emitting Diode (LED) on gingival inflammation, assessed by gingival crevicular fluid (GCF) interleukin-6 (IL-6) level, histomorphology, and immunohistochemical analysis of Tumor Necrosis Factor (TNF-α) and Cluster of Differentiation 8 (CD8) expression, with and without gingival barrier protection. Thirteen volunteers requiring gingivoplasty were included. The whitening procedure was performed with parameters of 400 nm, 134J/cm, and 20 cycles of 30 sec with 60 sec of standby. Gingival surgery was performed 48 h post-whitening for histomorphology analysis, while GCF IL-6 levels were quantified using an Enzyme-Linked Immunosorbent Assay (ELISA). We also attempted immunohistochemical analysis of TNF-α and CD8 expression; however, the small gingival specimens, which were primarily epithelial tissue, limited the reliability of the results. No statistically significant differences were observed between sides for histomorphology or GCF IL-6. These findings suggest that LED whitening without a gingival barrier may not induce gingival inflammation. However, further studies with larger and gender-balanced samples, extended time points, and additional cytokine markers are needed to confirm these results.

Fractional carbon dioxide (CO) laser is the standard treatment in facial rejuvenation for light skin phototypes; nevertheless, in Latin America, it is one of the most performed procedures on phototypes III-V. The goal of this study is to evaluate the improvement in facial skin aging in Latin skins with fractional CO laser and its side effects in a period of 3 months. Descriptive multicenter cross-sectional study including 165 patients from 2 medical centers in Latin America who attended from 2014 to 2021. Data were collected from medical records and assessment of facial aging was performed through photographic records by two independent investigators. An arithmetic mean was obtained for each variable and for each researcher, subsequently the obtained values were averaged to find the overall average improvement according to the intervention and skin phototype. A Cohen's Kappa Concordance Test was performed to determine the agreement between observers beyond chance. Significant improvement in fine lines, mottled pigmentation, and overall skin appearance was observed in patients treated with fractional CO laser with or without platelet-rich plasma. As for side effects, only one patient presented with herpes simplex. There are few studies to date that evaluate the use of fractional CO laser in Latin skins, through this research, it is evident that this technology has good results for facial rejuvenation in this type of patients and few side effects.

Depression is a prevalent mental disorder characterized by mental suffering and emotional distress. Its pathogenesis involves the concurrent action of multiple factors, including genetic predisposition, stress exposure, hypothalamic-pituitary-adrenal axis dysregulation, imbalances in neurotransmitters and their receptors, inflammatory responses, and mitochondrial malfunction. Photobiomodulation (PBM), a noninvasive therapeutic approach, has shown potential in treating mood disorders such as depression and has emerged as a promising intervention for various pathologies; however, unified standards for PBM irradiation parameters (e.g., based on species, gender, age) are currently lacking. This review aims to introduce the potential mechanisms underlying depression and summarize the latest pre-clinical and clinical progress of PBM in the treatment of this mood disorder. As a narrative review, this work synthesizes and analyzes existing literature on the pathological mechanisms of depression and the application of PBM in depression treatment. Results Polytherapy with PBM targeting multiple biological pathways exerts beneficial effects on depression. Specifically, PBM enhances mitochondrial function in the brain, promotes neurogenesis and synaptogenesis, regulates neurotransmitter homeostasis, and provides neuroprotection through anti-inflammatory and antioxidant actions, while simultaneously supplying energy to brain tissues. Additionally, the curative effect of PBM is found to be associated with multiple factors, including irradiation parameters, species, gender, and age, highlighting the lack of unified parameter standards in current research. PBM exhibits therapeutic potential for depression by modulating key pathological pathways (e.g., mitochondrial function, neurogenesis, inflammation). The latest pre-clinical and clinical evidence supports its role as a promising noninvasive intervention. However, the establishment of unified PBM irradiation parameters is essential for standardizing its clinical application in depression treatment. Future research should focus on optimizing parameter standards to enhance the efficacy and reproducibility of PBM therapy.

This in vitro study aimed to compare the antibacterial properties of 2% chlorhexidine (CHX) and 0.2% nano chitosan, with and without Er:YAG laser activation using a side-firing tip, against . It evaluates their potential to improve disinfection in endodontic treatments and assesses the impact of laser activation on antimicrobial efficacy. Successful endodontic treatment relies on effective root canal disinfection, often hindered by , which invades dentinal tubules. While sodium hypochlorite is effective, it can cause cytotoxicity and dentin damage. CHX is a biocompatible alternative, and nanochitosan offers promising antimicrobial properties with low toxicity. However, conventional irrigation methods are often insufficient. Er:YAG laser activation enhances irrigant penetration into dentinal tubules, improving antimicrobial effects. Extracted human premolars were inoculated with and divided into four groups: Group A (2% CHX), Group B (0.2% nano chitosan), Group C (2% CHX + Er:YAG laser), and Group D (0.2% nano chitosan + Er:YAG laser). Bacterial counts were measured using colony-forming units on Mueller Hinton agar. CHX showed superior antibacterial efficacy compared with nanochitosan. Laser activation significantly enhanced the antimicrobial effect of both irrigants, with Group C (CHX + laser) showing the greatest reduction in bacterial colonies. Er:YAG laser activation improves the antimicrobial effectiveness of both CHX and nano chitosan, particularly in combination, offering a promising approach for root canal disinfection. Furthermore, clinical studies are needed to confirm these findings in vivo.

Photodynamic therapy (PDT) combined with biliary stenting reportedly has better efficacy and safety in the treatment of extrahepatic cholangiocarcinoma (EHC). Considering the shortcomings of traditional PDT methods, we proposed a novel modified approach, defined as initial biliary stent placement followed by PDT, for the treatment of EHC. The study aimed to evaluate the effect and safety of biliary stent placement prior to PDT versus only stent placement on the treatment of EHC. A total of 30 patients diagnosed with EHC between January 2017 and December 2024 were included in the retrospective study. Ten patients underwent biliary stent placement, followed by PDT (Stenting with PDT group). Survival time, surgical success rate, and postoperative adverse events were compared to 20 patients receiving biliary stent placement alone (Stenting only group). The success rate of all operations in both groups was 100%. After 96 months of follow-up, the stenting with PDT group had significantly longer median survival after stent placement than the stenting only group (10.5 vs. 4.0 months, = 0.028). There were no statistically significant differences in the rates of postoperative total adverse events (5 [25%] vs. 2 [20%], = 1.000), asymptomatic hyperamylasemia (1 [5%] vs. 1 [10%], = 1.000), acute pancreatitis (4 [20%] vs. 1 [10%], = 0.272), and postoperative acute cholangitis (0 vs. 1 [10%], = 0.333) between the two groups. Compared with stenting alone, modified stenting combined with PDT resulted in longer survival in patients with unresectable EHC without significant adverse events.

Cisplatin (Cis), a key cancer chemotherapy drug, faces limitations such as dose-dependent side effects and resistance. Photobiomodulation therapy (PBMT) shows promise as an adjuvant therapy to enhance Cis efficacy and reduce side effects. A systematic review was conducted to evaluate the combined effects of PBMT and Cis on various cancers. After searching five databases using relevant keywords, nine studies were included, encompassing both in vitro and in vivo models. Most in vitro studies showed a synergistic effect, with enhanced cancer cell inhibition, apoptosis induction, and reduced cell viability compared with Cis alone. The animal model confirmed these findings, showing PBMT mitigated Cis-induced acute renal failure. Mechanistically, PBMT may increase reactive oxygen species generation, cytochrome c release, modulate cellular metabolism, and involve the miR-124/STAT3 signaling pathway. Combining PBMT with Cis appears to be a safe and effective cancer treatment strategy, synergistically inhibiting cancer cell growth and reducing side effects. Further clinical trials are needed to validate these findings.

Photobiomodulation (PBM) therapy involves the use of low-dose, nonionizing light to reduce pain and inflammation, promote wound healing, and enhance tissue regeneration. PBM-based therapy of various dental conditions is associated with improved treatment outcomes. This study aims to critically review the literature to highlight the underlying molecular biological mechanisms and clinical applications of PBM in modern dental practice. This critical review employed literature search in PubMed/Medline, Google Scholar, and ScienceDirect databases to determine biological basis of PBM with a particular focus on its clinical dental applications. English literature published in the past 25 years were eligible for inclusion. Selected studies were analyzed to evaluate the therapeutic biochemical effects of PBM, with a focus on its dental applications. PBM exerts its biological effects by influencing cytochrome c oxidase, increasing adenosine triphosphate, and improving DNA replication and RNA transcription. Various transcription factors and signaling pathways are involved through the activation of secondary messengers such as reactive oxygen species, nitric oxide, and cyclic adenosine monophosphate. The favorable biological effects of PBM can be beneficial for various dental applications in pulp therapy, management of postsurgical complications, and temporomandibular joint disorders. PBM represents a promising and effective treatment modality for the management of several challenging dental problems in the pediatric and adult populations, offering improved treatment outcomes, namely enhanced wound healing and reduced inflammation. Further research is recommended to optimize technical settings and standardize current protocols in the aim of enhancing clinical outcomes, exploring more applications, and improving patient satisfaction.

To determine how Erbium-doped yttrium aluminum garnet (Er:YAG) laser irradiation affects the proliferation and transcriptional programs of MLO-Y4 osteocyte-like cells. Although Er:YAG lasers are widely used in periodontal hard tissue therapy, how they affect osteocytes remain elusive. MLO-Y4 cells were seeded before 72 h Er:YAG laser irradiation at energy fluences of 3.1, 6.0, and 8.9 J/cm. Cell surface temperature and expression were measured to evaluate thermal effects. Cell proliferation and cytotoxicity were assessed by the Cell Counting Kit-8 (CCK-8) and lactate dehydrogenase (LDH) assays. RNA sequencing (RNA-seq) was performed 6 h after 6.0 J/cm laser irradiation versus nonirradiated controls. According to surface temperature and expression, no major thermal effects were observed at 6.0 J/cm. The CCK-8 assay revealed significantly increased proliferative activity, although LDH levels were slightly but significantly increased at 6.0 J/cm laser irradiation. RNA-seq identified 337 differentially expressed genes (DEGs). Expression of mechanical stimulation-associated genes, including , , and , was highly upregulated in the laser-irradiated cells. Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed upregulation of the PI3K-Akt signaling pathway in the laser-irradiated cells. Upregulated DEGs belonged to the "euchromatin" cellular component Gene Ontology term in the laser-irradiated cells. Gene set enrichment analysis showed enrichment of the Transforming Growth Factor Beta (TGF-β) signaling gene set and downregulation of mechanistic target of rapamycin (mTORC1) signaling gene set in the laser-irradiated cells. Er:YAG laser irradiation at 6.0 J/cm promotes MLO-Y4 osteocyte-like cell proliferation via altering gene expression, possibly by activating PI3K-Akt and TGF-β signaling while suppressing mTORC1 signaling.

The current study sought to explore the impact of a novel noninvasive treatment called transcranial photobiomodulation (PBM) on resting-state functional connectivity (rsFC) of the cerebellum in individuals with a history of repetitive head acceleration events (RHAEs). RHAEs are associated with cumulative neurological compromise, including chronic alterations in rsFC; however, few treatments have been investigated to mitigate these effects. A recent study by our team demonstrated that PBM treatment led to improvements in measures of balance and motor function in adults with RHAE exposure. Due to the cerebellum's role in motor functioning and its connectivity with cerebral regions targeted by PBM, we sought to examine changes in the rsFC of the cerebellum following PBM treatment. Thirty individuals with RHAE used an at-home PBM headset with an intranasal cannula for 20 min every other day for a period of 8-10 weeks. A total of 240 J/cm of red and near-infrared light was administered to cortical nodes of the default mode network (DMN) and subcortical structures in each session. Using resting-state functional magnetic resonance imaging, rsFC was measured before and after treatment in 11 cerebellar seed regions associated with the DMN, salience network (SN), and frontoparietal network (FPN). We observed an overall decrease in between-network connectivity and an increase in within-network connectivity after PBM treatment, particularly in the SN and FPN. These results suggest that PBM may improve network efficiency of the cerebellum by regulating overactive connections and increasing network segregation.

Photobiomodulation Valeda (PBM-Valeda) is a novel therapeutic approach for dry age-related macular degeneration (AMD). The primary objective of this short-term study was to conduct an analysis of best-corrected visual acuity (BCVA) and evaluate of biomarkers using state-of-the-art high-resolution imaging with swept-source optical coherence tomography OCT (SS-OCT) and OCT angiography (SS-OCTA) in dry AMD patients treated with PBM. This prospective, noncomparative, interventional case series pilot study examined the following biomarkers before and after PBM treatment: BCVA, central macular thickness (CMT), subfoveal choroidal thickness (SCT), capillary density (CD), avascular area of the superficial plexus (AASP), and avascular area of the deep plexus (AADP). All parameters were assessed at baseline and 1 week after treatment. A questionnaire (exploratory, not a validated endpoint) was carried out at the end of the treatment. The study included 25 eyes (19 patients), predominantly in the Age-Related Eye Disease Study category II. A statistically significant change in BCVA was observed ( = 0.001). No statistically significant changes were observed in CMT, SCT, CD, AASP, or AADP ( > 0.05). The treatment was well tolerated, with few mild side effects, and no patient developed wet AMD. PBM-Valeda therapy demonstrated a favorable short-term safety profile in patients with dry AMD. The key finding of this study was the stability of SS-OCT and SS-OCTA biomarkers (CMT, SCT, CD, AASP, and AADP), with no adverse changes observed. These results reinforce the short-term safety of PBM. Reported side effects were minimal, with no evidence of retinotoxicity. This is the first prospective study to explore SS-OCT and SS-OCTA biomarkers in patients with dry AMD undergoing PBM therapy, providing preliminary safety data for future controlled trials.

Temporomandibular joint disorders (TMDs) are multi-factorial conditions with a chronic progression that affects individual's quality of life (QOL). Currently, there is no definitive treatment for TMDs. Few clinical trials have investigated the potential effects of Photobiomodulation therapy on the acupuncture points on these disorders. Twenty patients with TMD, referred to the facial pain clinic at Semnan Faculty of Dentistry, were randomly assigned into two groups: treatment ( = 10) and placebo ( = 10).Treatment group received low-power Photobiomodulation therapy for 3 min at each of 10 acupuncture points, including GB20, SI19, ST6, ST7, and LI4. The placebo group received only the guiding light of the device on the same points. Treatment consisted of 10 sessions (twice a week). QOL was assessed using the OHIP-14 and SF-36 questionnaires at the beginning and end of treatment. Significant differences were observed between the treatment and placebo groups according to pain relief and maximum mouth opening ( < 0.05; Mann-Whitney). However, no significant difference was observed between the groups for the QOL using OHIP-14. In contrast, the SF-36 showed significant improvements in the physical health subscale in the treatment group. Photobiomodulation therapy on the acupuncture is a complementary, noninvasive therapy that may benefit patients with TMDs.

Laser hemorrhoidoplasty (LHP) has emerged as a minimally invasive alternative to excisional hemorrhoidectomy, but data remain heterogeneous, particularly regarding energy settings and safety outcomes. This multicenter retrospective cohort included 100 patients with symptomatic grade III hemorrhoids treated with LHP across six Brazilian centers between January 2021 and August 2023. Primary outcomes were postoperative pain (Visual Analog Scale-VAS), proctological symptoms (Proctological Symptoms Scale-PSS), and complications. Associations between total laser energy and complications were analyzed using multivariable logistic regression. Median VAS peaked at 3.0 on day 7 and declined to near-complete remission by day 14, remaining minimal up to 1 year. PSS scores improved in parallel, reaching zero from day 30. The 30-day complication rate averaged 19.7%, peaking at 27% on day 14, with a cumulative per-patient rate of 44%. Most complications were mild (edema, skin tags), and only four patients required reintervention. Higher total energy was associated with increased complications from day 14 onwards, although the clinical effect was modest. Adjunctive CO laser excision of skin tags ( = 49) did not increase morbidity. LHP proved safe and effective for grade III hemorrhoids, ensuring early pain relief and symptom resolution with high satisfaction. Energy standardization may help minimize risks, and adjunctive CO skin-tag excision appears feasible without added morbidity.

Rheumatoid arthritis (RA) is a persistent inflammatory condition that results in joint deterioration and impairment. A noninvasive treatment option that has shown promise is photobiomodulation therapy (PBMT), but the optimal energy density for RA management is not well established. This study aims to assess the therapeutic efficacy of PBMT utilizing varying energy densities on RA in male rats, in comparison with methotrexate treatment. A case-control study was conducted on 48 male rats randomly assigned to six groups: Group I is the negative control, Group II is the RA positive control, Group III is the RA + PBMT 36 J/cm, Group IV is the RA + PBMT 54 J/cm, Group V is the RA + PBMT 72 J/cm, and Group VI is the RA plus methotrexate. RA was induced in all groups except Group I. Treatments were applied over a defined period. Outcomes included paw thickness and biochemical markers: superoxide dismutase (SOD), interleukin-6 (IL-6), interleukin-1β (IL-1β), malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-α), and rheumatoid factor. All PBMT-treated groups showed significant reductions in paw thickness, and pro-inflammatory indicators were compared with the RA positive control ( < 0.05). PBMT at 54 J/cm (Group IV) demonstrated the most pronounced anti-inflammatory effect, comparable with methotrexate. Oxidative stress marker MDA decreased significantly, while SOD levels increased in all PBMT groups, particularly in Group IV. PBMT at an energy density of 54 J/cm appears optimal in mitigating inflammation and oxidative stress in RA, providing a potential non-pharmacologic adjunct to conventional therapy.

Transcranial photobiomodulation (tPBM) is a promising noninvasive neuromodulation modality with potential therapeutic benefits for neurodegenerative diseases. Infrared light delivered by a tPBM device penetrates the cortex, stimulating neuronal activity by increasing mitochondrial adenosine triphosphate production and enhancing regional cerebral blood flow. This study investigated the efficacy and safety of a self-administered, at-home, wearable tPBM device for improving cognitive function in individuals with mild cognitive impairment (MCI) due to Alzheimer's disease (AD). Individuals with MCI due to AD, diagnosed according to the National Institute on Aging and Alzheimer's Association criteria, with a Korean version of Mini-Mental State Examination-2 (K-MMSE2) score of 23-27 and a global Clinical Dementia Rating (CDR) score of 0.5-1.0 were enrolled. Subjects self-administered tPBM six times per week for 12 weeks. Assessments were conducted at weeks 7 and 13 using the Korean version of the Montreal Cognitive Assessment (K-MoCA), K-MMSE2, the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease, and the Geriatric Depression Scale. A total of 26 participants were enrolled. The treatment group showed a statistically significant improvement in K-MoCA scores at week 13 ( < 0.05) compared with the sham group. Although K-MMSE2 scores improved in the treatment group, the difference was not statistically significant. No serious adverse events were reported. Findings suggest that tPBM is an effective and safe home-use intervention for individuals with MCI, with promising therapeutic and preventative roles in Alzheimer's dementia.