Photobiomodulation, photomedicine, and laser surgery最新文献

Background: Nerve guidance conduits (NGCs) are a clinically approved option for peripheral nerve repair but remain ineffective compared with autograft "gold standard" treatment options. A combinatorial approach to conduit-based peripheral nerve repair could improve repair outcomes. Photobiomodulation therapy (PBMT) has shown potential to enhance axonal regeneration, but its efficacy in combination with NGCs requires further evaluation.

Objective: This pilot study investigated the therapeutic potential of a novel 3D-printed, collagen-based NGC combined with PBMT for peripheral nerve regeneration in a 10 mm rat sciatic nerve injury model.

Materials and methods: A total of 36 male, 3-month-old, Sprague-Dawley rats were used in a pre-clinical rat model of peripheral neurotmesis and randomly assigned to one of three groups (N = 12 each): Autograft (control), NGC-PBMT (experimental), and NGC + PBMT (experimental). All groups were further subdivided (N = 6) by recovery period (3 or 6 weeks). Collagen-based NGCs were fabricated via DLP 3D printing and implanted into rats with 10 mm sciatic nerve transections. PBMT treatment was applied transcutaneously every other day at 980 nm for 30 s at 1 W. Gross examination, immunohistochemistry, and immunofluorescence were used to assess biocompatibility, vascularization, and nerve regeneration at 3- and 6-weeks post-surgery.

Results: Gross examination revealed no sign of inflammation or immune rejection, with significant neovascularization observed throughout the NGCs. Immunostaining demonstrated nerve regeneration in all groups, with progressive axonal growth from week 3 to 6 in the NGC-PBMT group. However, neither experimental group achieved regeneration comparable to the autograft control. PBMT did not yield significant improvement in regenerative outcomes under the tested parameters.

Conclusions: Altogether, this study provides encouraging preliminary evidence that these novel, 3D-printed NGCs are biocompatible and promote early nerve regeneration after peripheral neurotmesis. While PBMT did not enhance outcomes in this study, further work is needed to optimize light delivery parameters and improve conduit design for enhanced neuroregeneration.

Objective: The aim of this study was to evaluate the effects of photobiomodulation (PBM) at 635 nm on human gingival fibroblast (HGF) behavior in an in vitro wound-healing model.

Background: PBM has gained increasing interest in periodontal therapy due to its potential to modulate inflammation and stimulate regenerative processes. Despite promising applications, the most effective parameters for periodontal tissue remain unclear, particularly regarding wavelength, energy density, and irradiation frequency. Understanding cellular responses under controlled conditions is essential to define PBM's therapeutic role in periodontal regeneration.

Methods: HGFs were cultured in a wound-healing model and subjected to PBM using a 635 nm diode laser. Cell proliferation, migration, wound closure, and morphology were assessed at 24 and 48 h and compared with untreated controls. To distinguish proliferation from migration, wound closure was also evaluated in the presence of mitomycin C, and metabolic activity was measured by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] at 48 h.

Results: PBM significantly accelerated defect closure at 24 h, with higher cell density along the wound margin and increased mitotic figures. By 48 h, wound closure percentages converged between groups. In the presence of mitomycin C, PBM did not significantly enhance migration, indicating that the early wound closure is primarily driven by proliferation. PBM-treated cultures also displayed a more uniform wound margin, suggesting moderated migratory activity. MTT assay confirmed increased metabolic activity in PBM-treated cells at 48 h.

Conclusions: PBM at 635 nm promotes early enhancement of fibroblast growth and gap colonization in vitro, with effects most evident within the first 24 h. These findings suggest that PBM primarily stimulates cell growth rather than migration in the early phase of wound healing and support its potential as an adjunctive tool in gingival and soft tissue repair, particularly in contexts requiring a balance between cellular proliferation and migration.

Objective: To evaluate the effects of photobiomodulation (PBM) on glycemic control in individuals with type 2 diabetes mellitus (T2DM). Persistent hyperglycemia in T2DM disrupts mitochondrial metabolism, increases oxidative stress, and contributes to metabolic and vascular complications. PBM has emerged as a potential nonpharmacological strategy to modulate mitochondrial function and improve metabolic homeostasis.

Methods: Recent clinical trials investigating PBM in T2DM were systematically synthesized. Methodological quality was assessed using the Physiotherapy Evidence Database scale, and certainty of evidence was evaluated with the Grading of Recommendations, Assessment, Development, and Evaluation approach.

Results: PBM, predominantly using red and near-infrared wavelengths, was associated with reductions in fasting glucose, postprandial glucose, and glycated hemoglobin, as well as modulation of hemodynamic and metabolic parameters. Methodological quality ranged from moderate to high, while certainty of evidence was very low to low.

Conclusions: PBM shows potential as an adjunctive therapy for glycemic control in T2DM, although further well-designed trials are required to strengthen evidence and standardize protocols.

Prostate cancer ranks highest in male diagnoses and second in cancer-related deaths. Conventional treatments necessitate exploration of new modalities due to their side effects. Sonophotodynamic therapy (SPDT) represents a potential anticancer approach that integrates both sonodynamic and photodynamic therapies to improve the efficacy of cancer treatments. This study aims to evaluate and compare the mechanisms and anticancer efficacy of photodynamic therapy, sonodynamic therapy, and SPDT using methylene blue (MB) and aluminum phthalocyanine (AlPc) in the androgen-sensitive and androgen-insensitive prostate cancer cell lines. Cells were cultivated using different concentrations of MB and AlPc, followed by the exposure to ultrasound and/or light irradiation. Cell metabolic activity was assessed using the MTT assay, which evaluates mitochondrial enzyme function as an indicator of viability rather than clonogenic survival. Additionally, apoptosis was evaluated using Hoechst staining and Western blot analysis of apoptotic proteins, while reactive oxygen species (ROS) and antioxidant levels were determined through biochemical assays. Results showed significant proliferation inhibition, with SPDT exhibiting the highest efficacy. MB demonstrated superior efficiency compared to AlPc. The treatment groups displayed a greater quantity of apoptotic cells, indicating elevated levels of caspase-3, caspase-8, PARP, and Bax proteins, whereas levels of caspase-9 and Bcl-2 were lower compared to the control groups. Additionally, the treatments resulted in increased levels of ROS and malondialdehyde, while antioxidant activities were diminished. In summary, SPDT mediated by MB and AlPc presents promising potential for treating prostate cancer and may significantly contribute to apoptotic mechanisms.

Purpose: Demodex folliculorum infestation is an important contributor to meibomian gland dysfunction (MGD) and chronic ocular surface disease. This study evaluated and compared the therapeutic efficacy of intense pulsed light (IPL) and eyelid hygiene (ELH) for Demodex-associated MGD.

Methods: In this prospective, randomized comparative trial, 50 patients (100 eyes) with Demodex-associated MGD were allocated to two arms. Group A (n = 25) received three Eyesis IPL sessions at baseline, week 2, and week 4. Group B (n = 25) performed daily eyelid hygiene with OCuSOFT Lid Scrub for 6 weeks. Ocular surface parameters, including ocular surface disease index (OSDI), tear film lipid layer thickness (TFLL), noninvasive tear film break-up time (NITBUT), meibomian gland dropout, meibum quality and expressibility, corneal fluorescein staining (CFS), Schirmer's I, and Demodex count, were assessed from baseline to week 6. Best-corrected visual acuity (BCVA) and intraocular pressure (IOP) were recorded at each visit.

Results: Both treatments significantly improved OSDI, NITBUT, TFLL, Schirmer's I, and CFS over 6 weeks (all p < 0.001). Compared with ELH, IPL achieved larger and earlier reductions in symptoms, greater increases in TFLL, and superior improvements in meibum quality and expressibility from week 4 onward (between-group p ≤ 0.021). Demodex counts decreased significantly in both groups with no between-group difference at week 6. BCVA, IOP, and adverse events remained stable, indicating a favorable short-term safety profile.

Conclusion: IPL and ELH are effective for Demodex-related MGD, but IPL provides faster and more pronounced improvements in meibomian gland function, tear film stability, and patient-reported symptoms over 6 weeks.

Aim: An in vitro study to evaluate the efficacy of indocyanine green (ICG) encapsulated in chitosan (CHNPs) and titanium dioxide nanoparticles (TiO₂NPs) activated by 810-nm diode laser on smear layer (SL) removal and shear bond strength (SBS) to caries-affected dentin (CAD).

Materials and methods: Sixty extracted human mandibular molars with CAD were randomly assigned to four groups (n = 15). Group 1: 2% chlorhexidine (CHX), Group 2: free ICG-activated PDT (ICG-PDT), Group 3: ICG-loaded TiO₂NPs-activated PDT (ICG-TiO₂NPs-PDT), and Group 4: ICG-loaded CHNPs-activated PDT (ICG-CHNPs-PDT). CHNPs and TiO₂NPs were characterized by scanning electron microscopy (SEM) energy-dispersive X-ray spectroscopy. SL removal was assessed qualitatively via SEM using the Hülsmann scale. A fifth-generation etch-and-rinse adhesive was applied with active scrubbing, and nanohybrid composite buildups were fabricated. Following thermocycling, SBS was measured using notched-edge shear testing machine. Failure modes were assessed stereoscopically. Data were analyzed using one-way ANOVA and Tukey post hoc tests (α = 0.05).

Results: ICG-CHNPs-PDT yielded the lowest SL score (1.04 ± 0.14) and highest SBS (9.79 ± 0.62 MPa), significantly outperforming all groups (p < 0.05). CHX exhibited intermediate performance (SL: 2.16 ± 0.48; SBS: 7.59 ± 0.46 MPa). ICG-PDT (SL: 2.75 ± 0.29; SBS: 6.12 ± 0.43 MPa) and ICG-TiO₂NPs-PDT (SL: 2.81 ± 0.35; SBS: 5.97 ± 0.35 MPa) showed comparable, inferior results (p > 0.05). ICG-CHNPs-PDT demonstrated predominantly cohesive failures (60%), while ICG-PDT and ICG-TiO₂NPs-PDT showed mainly adhesive failures (50%).

Conclusion: Near-infrared antimicrobial photodynamic therapy using chitosan-encapsulated ICG activated at 810 nm significantly enhanced both SL removal and resin-dentin bond strength compared with conventional CHX. The dual chelating and photosensitizing properties of the chitosan-ICG system offer a promising alternative for CAD surface conditioning before adhesive bonding.

Objective: To evaluate the effects of beyond cold light whitening and desensitization on shear bond strength of orthodontic metal brackets.

Materials and methods: Ninety-eight extracted human premolars were randomly divided into seven groups (n = 14). Group 1 was the control (no treatment). Group 2 underwent bleaching, followed by bonding after 24 h. Group 3 received desensitization, then bonding after 24 h. Group 4 combined bleaching and desensitization, with bonding after 24 h. Groups 5, 6, and 7 followed the same procedure as Group 4, but bonding occurred 1, 2, and 3 weeks later, respectively. All samples were stored in 37°C artificial saliva after treatment and bonded with 3 M light-cure composite resin using halogen light. Shear bond strength was tested with a universal testing machine (INSTRON 5848). Adhesive remnant index (ARI) scores were assessed post-debonding. Statistical analysis was conducted using Analysis of Variance (ANOVA), Tukey's test, and chi-square tests, with significance set at p < 0.05.

Result: The shear bond strength 24 h after bleaching (7.5 ± 1.77 MPa) was significantly lower than the control (12.24 ± 3.71 MPa, p < 0.05). Desensitization alone (11.68 ± 3.49 MPa) showed no significant difference compared with the control (p > 0.05). Shear bond strength significantly decreased 24 h after bleaching and desensitization (p < 0.05) but recovered to control levels after 1 week (p > 0.05). ARI scores showed no significant differences.

Conclusions: (1) Brackets bonded 24 h after bleaching or combined treatment showed reduced shear bond strength but were clinically acceptable; (2) The use of nano-biomaterial desensitizers slightly reduces the shear strength of brackets, but it will repair the damage of teeth caused by bleaching; (3) The impacts of bleaching and desensitization gradually reduce and return to normal levels after 1 week.

Introduction: Radiation-induced oral mucositis (RIOM) may cause severe pain and impaired quality of life during head and neck radiotherapy (RT). Preventive photobiomodulation (PBM) has shown promising clinical benefits.

Materials and methods: Eligible patients had oropharyngeal or oral cavity cancer and were opioid-naïve at the start of curative-intent RT. Patients in the PBM group were treated between 2020 and 2023. PBM was applied to the entire oral mucosa at 2.25 J/cm² (λ = 660 nm). Extraoral PBM was delivered using an LED cluster device at 6 J/cm² (λ = 810 nm) to target the pharyngolaryngeal mucosa. PBM was administered three times per week by trained radiation therapists. A historical control cohort treated between 2012 and 2019 was matched 1:1 based on tumor site, concurrent systemic therapy, and prior surgery. The primary objective was to evaluate differences in daily morphine consumption at the end of RT according to the preventive use of thrice-weekly oral PBM in patients receiving curative-intent RT for head and neck cancer.

Results: A total of 280 patients were included: 45% had oral cavity cancers, 43% were treated postoperatively, and 42% received RT without systemic therapy. Morphine use was significantly lower in the PBM group at the end of RT (22.9 vs. 37.4 mg/day; p = 0.002) and 1 month post-RT (10.3 vs. 27.2 mg/day; p = 0.0001). No morphine was required in 60% of PBM patients compared with 47% of controls. PBM appeared particularly beneficial in oropharyngeal cancer, in patients receiving definitive RT, and with concurrent treatment. In contrast, rates of grade 3-4 RIOM at the end of RT were identical (63% in both groups), and grade 3-4 mucositis-free survival did not differ (p = 0.99).

Conclusion: In this large matched cohort, preventive PBM reduced morphine consumption during and after RT, supporting its use to alleviate RIOM-related pain in head and neck cancer patients.

Objective: In sports, achieving peak performance and overcoming injuries are critical for athletes at all levels. This narrative review, aligned with PRISMA guidelines, synthesizes evidence from 7 human and animal studies on the effects of transcranial photobiomodulation (tPBM) in sports medicine, focusing on athletic performance.

Results: tPBM, which uses red and near-infrared light, offers a noninvasive approach that has shown preliminary evidence of enhancing motor function, cognitive performance (e.g., attention, decision-making), and muscle strength while reducing neuroinflammation and aiding recovery from neurological damage. However, evidence for mitigating injury, particularly for traumatic brain injuries, is limited and primarily derived from animal models or human studies with methodological limitations, such as small sample sizes or lack of sham controls. Challenges include inconsistent protocols and limited research on elite athletes. tPBM may hold potential as a complementary tool to traditional approaches, but further rigorous trials are needed to establish standardized protocols and confirm its efficacy. Future trials should prioritize larger samples, sham-controlled designs, athlete-specific cohorts, standardized protocols, and outcome measures such as reaction time, executive function, grip strength, and balance control.