Lasers in Medical Science最新文献

To evaluate and compare clinical outcomes, radiographic healing and regenerative biomarkers in laser-irradiated and non-irradiated groups undergoing regenerative endodontics in immature permanent teeth over a 12-month follow-up period. Twenty-eight patients with necrotic immature roots were assigned to one of two groups: a control group (n = 14) receiving standard regenerative endodontic procedure (REP) with a mock laser application, or an experimental group (n = 14) receiving standard REP with adjunctive low-level laser therapy (LLLT). Both groups underwent initial medication with double antibiotic paste. In the experimental group, a diode dental laser (810 nm, 4.5 J/cm², 0.3 W, 9 s) was applied to the apical third every 48 h for 14 days. After 21 days, intracanal bleeding was induced, and blood samples were collected for regenerative marker analysis using ELISA. Mineral trioxide aggregate was placed, followed by coronal restoration. Clinical symptoms and radiographic healing were monitored over 12 months, with statistical analysis performed using the independent t-test at a 95% confidence level. Clinically, both groups demonstrated high success rates (85.7% in the laser group vs. 78.6% in the control group; p = 0.83). No statistically significant differences were observed when pain and radiographic parameters were compared over time between the groups. Considering the biomarkers, only DSPP expression was significantly higher in the laser group (p = 0.03). For the other biomarkers (VEGF, TGF-β, MMP-8, PDGF-BB), the laser group showed numerically higher mean values, but these differences did not reach statistical significance (all p > 0.05). This study demonstrates that adjunctive low-level laser therapy (LLLT) during regenerative endodontic procedures produced comparable clinical and radiographic outcomes to standard treatment, with a significant increase in DSPP expression suggesting early molecular activation. While these findings indicate potential regenerative benefits, larger multicenter studies with extended follow-up are required to validate LLLT as an adjunct in clinical protocols. Trial registration: This trial was registered in the Clinical Trials Registry India (CTRI) under registration number CTRI/2024/01/062114 dated 31/01/2024.

This study aimed to compare the efficacy of low-power laser therapy (LPLT) and low-frequency ultrasound (LFU) in reducing pain and improving quality of life in patients with diabetic polyneuropathy (DPN). A randomized controlled trial was conducted involving 55 patients with DPN, randomly assigned to three groups: LPLT (n = 18), LFU (n = 15), and control (n = 22). The LPLT group received treatments three times weekly for four weeks at 6 J/cm² using 808 nm and 905 nm wavelengths. The LFU group received treatments three times weekly for four weeks at 1 MHz, 0.5 W/cm², and 20% duty cycle. All interventions were administered alongside standard medical care. Baseline and post-intervention assessments included the Michigan Neuropathy Screening Instrument (MNSI) and Quality of Life in Diabetic Neuropathy (QOL-DN) measures. At baseline, significant differences were observed in patient-reported MNSI scores (p = 0.001), with the LPLT group reporting the highest scores. Post-intervention, all groups showed reductions in MNSI scores, but between-group differences were not significant (p = 0.292). The LPLT group exhibited the largest mean reduction (-2.39) in patient-reported MNSI scores, though the change only approached significance (p = 0.057). For QOL-DN, the LPLT group showed the greatest improvement in symptom scores (Mean=-2.55, p = 0.023) and problem scores (Mean=-7.05, p < 0.001). ANCOVA confirmed a significant group effect for QOL-DN problem scores (p = 0.007), with the LPLT group showing significantly greater improvement than controls (p = 0.006). LPLT may have potential for improving quality of life and neuropathy symptoms in DPN patients, but the limited between-group differences indicate that its clinical utility remains uncertain. Larger, multicenter trials with longer follow-up are needed to confirm these preliminary findings and establish clinical relevance.

Monopolar radiofrequency (RF) devices are widely used for skin tightening, wrinkle reduction, and body contouring. However, frequency-dependent differences in energy absorption and tissue remodeling remain insufficiently characterized. This study aimed to compare the thermal distribution and histological responses induced by 6.78‑ and 2‑MHz monopolar RF, as well as their sequential combination. Finite-element computational modeling was used to simulate electric field propagation and heat diffusion in multilayered skin with varying subcutaneous fat thicknesses and fibrous septa configurations. In vivo experiments were conducted on porcine skin treated with 6.78‑, 2‑, and dual‑frequency RF modes. Histologic changes were evaluated using hematoxylin and eosin, Masson's trichrome, and Verhoeff-van Gieson staining. Apoptotic cell death was assessed using the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay to evaluate adipocyte viability. Computational modeling demonstrated that 2‑MHz RF produced broader and deeper thermal effects within the adipose tissue, whereas 6.78‑MHz RF generated more localized heating along the fibrous septa. Dual-frequency RF combines these effects, creating pronounced thermal reactions at the dermosubcutaneous junction. Histological analysis revealed significant collagen and elastin remodeling across the dermis and fibrous septa in dual-frequency-treated specimens, with no evidence of adipocyte apoptosis. Moreover, remodeling changes were more extensive and persistent at later time points, suggesting that dual-frequency treatments have a greater tissue remodeling potential compared with single-frequency applications. Dual-frequency monopolar RF effectively promoted extracellular matrix remodeling in the dermis and subcutis while preserving adipocyte viability, suggesting its use as a safe and versatile modality for skin rejuvenation and contouring.

Mental disorders are a leading cause of disability worldwide, with ongoing challenges in treatment effectiveness. Photobiomodulation (PBM) has emerged as a potential complementary approach for managing mental health conditions. This integrative review aimed to evaluate existing research on PBM in mental health, focusing on treated conditions, outcomes, safety, and research gaps. A systematic search was conducted across six databases: DOAJ, Embase, PubMed, LILACS, Medline, and SciELO. Rayyan^® software was used for article screening, with titles and abstracts independently reviewed by two evaluators using the "Blind on" feature to minimize bias. Included studies were clinical trials and case reports in English, Portuguese, Spanish, Italian, or German. Reviews, non-clinical studies, and those lacking full-text access were excluded. Extracted data included study design, protocol, outcomes, and limitations. Fourteen studies published through July 2025 were included, addressing conditions such as anxiety, depression, and seasonal affective disorder (SAD). PBM showed therapeutic potential, with reported improvements in brain activity, reduced anxiety, and antidepressant effects. Adverse events were infrequent and mild, including headaches, irritability, and difficulty sleeping. However, high variability in protocols-such as wavelength, application sites, and session duration-limits reproducibility and generalizability. PBM appears to be a safe and promising complementary option for mental health, particularly for anxiety, depression, and SAD. To validate its clinical utility, future research should prioritize large-scale, randomized controlled trials with standardized protocols. Additionally, exploring age- and sex-specific responses may support personalized treatment strategies.

Conventional suturing has inherent shortcomings like inflammation, wicking effect, and additional appointments for removal. Various suture alternatives have been described in the scientific literature with satisfactory results. This study was planned to evaluate and compare the clinical efficacy of Laser Tissue Welding (LTW) and conventional suturing after periodontal surgery. Patients indicated for periodontal flap surgery in bilateral quadrants were selected and randomly allocated to the two study groups. In Group I (Control), flap approximation was achieved with 3 - 0 black silk sutures. In Group II (Test), a 20% albumin and indocyanine green mixture was applied, and laser application was done at 1.5 W in a continuous waveform to achieve a welded tissue. Clinical parameters were assessed using the Plaque Index, Early Wound Healing Index, and Modified Sulcular Bleeding Index, which were recorded at baseline, 3rd, 7^th, and 14th postoperative days. Visual Analogue Scale (VAS) was used to measure postoperative pain at the 3rd ,7^th, and 14th day, and to estimate operative time, at the time of surgery. The intergroup comparison has demonstrated significant improvement with LTW in all clinical parameters, with reduced operative time compared to sutured sites. LTW can be used as an efficient suture alternative technique in periodontal surgeries.

Background: Post-traumatic trigeminal neuropathy (PTTN) can significantly affect quality of life (QoL) due to pain and sensory disturbances. This study aimed to evaluate the effectiveness of photobiomodulation (PBM) therapy in patients with long-standing neurosensory disturbances associated with PTTN, using a protocol implemented at our department.

Methods: A retrospective analysis was conducted on 76 cases treated between 2007 and 2018. All had neurosensory symptoms lasting more than 3 months. Data were collected from the clinical records, a structured questionnaire, and Visual Analogue Scale (VAS) scores. PBM therapy was administered using a GaAlAs diode laser. Patients were stratified based on time from injury to treatment (< 12 months vs. > 12 months).

Results: Following PBM therapy, 59% of patients reported subjective improvement (30% extensive, 29% slight), while 38% reported no change and 2.6% noted slight deterioration. No statistically significant differences were observed between the groups that responded to PBM therapy and those that did not. Similarly, treatment outcomes showed no significant association with gender, etiology, affected nerve, time to treatment, or number of sessions.

Conclusions: The current study did not demonstrate a statistically significant effect of PBM therapy in patients with neurosensory disturbances associated with PTTN under the applied treatment protocol. Due to the retrospective design, the absence of a control group, and the heterogeneity in patients, etiology, nerve injury types, and timing of treatment, we hypothesize that variables such as laser dosage, session intervals, and application technique may have influenced the lack of observed therapeutic benefit. Subjective improvements must be interpreted cautiously due to potential placebo effects and spontaneous nerve recovery. These findings underscore the need for standardized PBM protocols and well-designed randomized controlled trials (RCTs) to validate treatment efficacy in trigeminal nerve injuries.

Laser-Induced Thermotherapy (LITT) efficacy hinges on achieving localized heating and controlled vaporization within tumor tissue. Building upon our previously developed fully-coupled bioheat vapor bubble model, this study integrates gold nanoparticles (GNPs) to enhance optical absorption and bubble dynamics during LITT of breast tumors. Gold nanoparticles (spherical, ~ 60 nm diameter) were considered to enhance optical absorption and bubble dynamics. We introduce an additional heat-source term, [Formula: see text], to the Pennes bio heat equation, where [Formula: see text] ​and [Formula: see text] denote the nanoparticle absorption coefficient and concentration. Latent-heat effects and Rayleigh Plesset bubble dynamics are retained from the baseline model. Simulations were carried out for fluences of 30-80 J/cm² using an 800 nm near-infrared (NIR) Gaussian laser beam, applied as a 50 ms square pulse .Through simulations comparing nanoparticle rich ([Formula: see text] particles/mL) and nanoparticle free scenarios across laser fluences of [Formula: see text], our results show that GNPs reduce vaporization threshold fluence by approximately 20%, increase peak temperature by ~ 15 [Formula: see text] and elevate peak bubble radius from ~ 12 μm to ~ 18 μm. Sensitivity analyses reveal significant dependencies of necrotic zone size on nanoparticle parameters. This nanoparticle-enhanced model offers a powerful theoretical framework for optimizing LITT protocols, potentially reducing required laser doses and minimizing collateral damage.

To investigate the effects of Nd∶YAP laser-assisted periodontal therapy on masticatory function and gingival circulation indices in patients with chronic periodontitis. This retrospective cohort study included 140 patients with chronic periodontitis, admitted between May 2022 and December 2024. The patients were divided into two groups: 81 patients in the Nd: YAP laser group and 59 in the basic treatment group. The study compared treatment efficacy, periodontal parameters, masticatory function, gingival circulation, inflammatory cytokines in gingival crevicular fluid (GCF), and adverse reactions between the two groups. The Nd: YAP laser group showed a total effective rate of 95.06%, significantly higher than the basic treatment group (P < 0.05). The laser group also demonstrated greater improvements in periodontal indices, masticatory function, gingival circulation, and GCF inflammatory cytokines compared to the basic treatment group (P < 0.05). No significant adverse reactions were observed in either group. Nd: YAP laser-assisted basic periodontal treatment can improve the treatment effect of patients with chronic periodontitis to a certain extent, effectively improve periodontal indicators and chewing function, improve gingival microcirculation, and relieve inflammatory response. There are no obvious adverse reactions during the treatment, and it is relatively safe. It can be used as one of the auxiliary treatments for chronic periodontitis.