Journal of lasers in medical sciences最新文献

Introduction: Laser pointers are commonly used in various settings, including presentations, lectures, entertainment events, and toy applications. Although they have become increasingly popular, the misuse or accidental exposure to high-powered laser pointers can cause serious ocular injuries, including retinal damage. Methods: In this case series, we present many cases of retinal damage caused by laser pointers in patients who visited our clinic over the past year (from January 2024 to January 2025). Results: We discuss the clinical presentation, diagnostic findings, management, and outcomes of 32 patients with laser-induced retinal damage. Our findings highlight variable recovery patterns depending on injury severity, ranging from spontaneous resolution in some patients to complications requiring intervention in others. Conclusion: This study explored the potential visual damage caused by laser pointers and provided recommendations for safe usage.

Introduction: Increased tissue regeneration is facilitated by mesenchymal stem cells (MSCs), with photobiomodulation (PBM) effectively promoting their proliferation. This study examines the impact of PBM on human third molar follicle stem cells using three diode lasers, addressing the need for further investigation regarding its parameters. Methods: The third molar follicle stem cells of four consented patients were removed after surgical extraction of third molars. These cells were then exposed to laser radiation with wavelengths of 660 (energy density: 3 and 5.1 J/cm²), 808 (energy density: 3 and 5 J/cm ²), and 980 (energy density: 3.2 and 5/2 J/cm²) nanometers at time intervals of 24, 48, and 72 hours. The proliferation and viability of the cells were determined using the MTT test. The data were analyzed through one-way ANOVA followed by Tukey's HSD post hoc test, utilizing SPSS software version 22, with a significance threshold of 0.05. Results: The highest average number of human third molar follicle stem cells was obtained at 660 nanometers and an energy density of 5.1 J/cm² in 24 hours. This specific laser protocol significantly outperformed other conditions in promoting cellular proliferation. Conclusion: PBM at the 660-nm wavelength administered with a dose of 5.1 J/cm² and a 24-hour incubation period appears to be the most effective condition for enhancing the proliferation and survival of human third molar follicle stem cells. These findings provide a potential basis for standardized PBM protocols in regenerative dentistry.

Introduction: This study aimed to evaluate the effectiveness of a 660 nm diode laser in combination with 8% arginine-based toothpaste compared to the laser used independently for managing dentinal hypersensitivity (DH). Methods: A total of 12 patients with severe hypersensitivity were included in the study. Selected teeth were randomly assigned to a Test site (diode laser 660 nm+8% arginine toothpaste) and a control site (660 nm diode laser alone). The selected teeth were irradiated using a 660-nm diode laser at 25 mW power for 60 seconds at a 1cm² area (1.66×10 ^-6 J/m³) in continuous mode using multi-tip low-level laser therapy (LLLT) (8 mm). DH scores were assessed using the VAS and the SCASS at baseline, 15 minutes post-application, and on days 15 and 30. Results: Clinical parameters such as the visual analogue scale (VAS) and Schiff Cold Air Sensitivity Scale (SCASS) were expressed as mean±SD or median with IQR. The 660-nm diode laser with 8% arginine-containing toothpaste showed a notable and sustained reduction in mean VAS scores and SCASS scores 15 minutes post-application and on days 15 and 30, compared to the diode laser (660 nm) alone. A P value less than 0.05 was regarded as statistically significant. Conclusion: The adjunctive use of a diode laser (660 nm) with 8% arginine-containing toothpaste shows promise as a treatment alternative for alleviating DH. Unlike conventional desensitizing agents, which predominantly obstruct dentinal tubules or interfere with nerve response, this combination therapy reduces sensitivity immediately and sustainably via two mechanisms: laser-induced nerve modulation and arginine-mediated tubule occlusion. These findings imply that it could serve as a more effective alternative to standard desensitizing toothpaste or laser therapy when used alone.

Introduction: This study aimed to investigate the influence of different erbium-doped yttrium aluminum garnet (Er: YAG) laser pulse widths (pulse durations) on the shear bond strength (SBS) of layered ceramic to zirconia substructures. Methods: A total of 60 zirconia blocks (5 mm radius and 10 mm height) were divided into 6 groups. Group C received no treatment, while Group S was treated with sandblasting using aluminum oxide (Al₂ O₃). Groups L1, L2, L3, and L4 were irradiated with Er: YAG lasers with pulse widths of 50 µs, 100 µs, 300 µs, and 600 µs, respectively. The layered ceramics were applied using a custom index and then sintered. The specimens were mounted in acrylic resin and subjected to a SBS test at a speed of 0.5 mm/min using a universal testing machine until the bonding surface developed cracks. The mode of failure was observed under a microscope. Results: The highest SBS was observed in the L4 and L2 groups, followed by the L3, L1, and S groups. Group C showed the least SBS. However, no significant difference was found between laser groups (L1, L2, L3, and L4) and group S. Conclusion: In conclusion, this study highlights the importance of surface treatment in improving the bond strength of zirconia restorations. The use of Er: YAG laser irradiation can produce a rougher surface, which is beneficial for adhesion. These findings provide valuable insights for clinicians seeking to improve the durability and longevity of zirconia-based restorations.

Introduction: The solar radiation spectrum, which reaches the Earth's surface, spans from infrared to ultraviolet. In the present study, human skin response to solar-stimulation radiation was assessed via directed protein-protein interaction (PPI) network analysis. Methods: Data were extracted from the Gene Expression Omnibus (GEO) database. The gene expression profiles of human skin after exposure to 100J/M² versus the control were selected from GSE22083. The data were evaluated via box plot analysis and Uniform Manifold Approximation and Projection (UMAP) plot assessment. The differentially expressed genes (DEGs) were visualized via a Venn diagram. After cleaning the data, the queried DEGs were assessed via the directed PPI network by the application of the CluePedia plugin of Cytoscape software. The critical DEGs were pointed out based on out-degree value. Key actor genes were searched in GeneCards to find a suitable description of them. Results: Among 1482 significant DEGs, AURKA, CENPA, PP2R1B, UBE2O, RPA3, YKT6, SMARCA5, and SMAD3 were identified and highlighted as the critical actor genes in response to solar-stimulated radiation in human skin. Conclusion: In conclusion, AURKA appeared as the top-ranked DEGs in response to solar radiation in the human skin. Based on the findings, AURKA was pointed out as a suitable target against photoaging. The relationship between solar-stimulated radiation and photoaging, cancer promotion, innate immune system, DNA replication, repair of UV damage-induced, vesicular trafficking between the Golgi apparatus and the endoplasmic reticulum, exocytosis of neurotransmitter, exosome production, autophagy, maintenance of nucleosome spacing, and process of progressive fibrosis were established.

Introduction: Chronic orthopedic pain is a leading cause of disability worldwide, compromising physical function, independence, and quality of life. While pharmacological treatments are widely used, their prolonged use is often limited by side effects and suboptimal efficacy. Among non-pharmacological approaches, photobiomodulation-particularly low-level laser therapy (LLLT) and high-intensity laser therapy (HILT)-has emerged as a promising strategy due to its analgesic, anti-inflammatory, and regenerative properties. However, evidence regarding its clinical efficacy remains heterogeneous and fragmented. Methods: This systematic review was conducted in accordance with PRISMA guidelines and based on the PICO framework. Comprehensive searches were performed in PubMed, Embase, Scopus, LILACS, and Cochrane CENTRAL. Eligible studies were randomized controlled trials (RCTs) published in English, Spanish, or Portuguese over the past five years, involving adults (≥18 years) with orthopedic pain treated with LLLT or HILT. Outcomes of interest included pain intensity, physical function, and quality of life. Exclusion criteria included non-randomized trials, pediatric populations, and studies that did not isolate the effects of laser therapy. Results: From 59,873 records initially retrieved, eight RCTs met the inclusion criteria. The studies addressed diverse musculoskeletal conditions such as knee osteoarthritis, chronic low back pain, patellofemoral pain syndrome, plantar fasciitis, subacromial impingement, and lateral epicondylalgia. Both LLLT and HILT demonstrated efficacy in reducing pain and enhancing physical function. In several studies, HILT was associated with faster symptomatic improvement. Nevertheless, considerable heterogeneity in laser parameters, treatment protocols, and outcome measures hindered direct comparison and meta-analysis. Conclusion: The current evidence supports the use of both LLLT and HILT as safe and effective adjuncts in the management of orthopedic pain. Future trials should adopt standardized protocols and long-term follow-up to better define clinical guidelines and optimize treatment outcomes.

Introduction: Endodontic periapical (PA) lesions are common sequelae of pulpal infections and often require root canal therapy (RCT) for resolution. Large lesions near vital anatomical structures are more important. A minimally invasive approach involving both diode laser-assisted disinfection and photobiomodulation therapy (PBMT) might be more suitable as both are less invasive while suppressing deep infection and promoting tissue healing. Case Report: A 58-year-old female patient presented with a mandibular radicular cyst that extended from teeth #25 to #28 with a complicated buccal cortical perforation and proximity to the mental foramen. Treatment consisted of multi-visit root canal therapy with diode laser disinfection in the canals (980 nm, 200-µm fiber, 1 W, 1 second. for every 2 mm canal length, 4 passes) and PBMT (0.5 W, 30 seconds per point, 6 points; 7 sessions over 4 weeks) for the canals. Conclusion: This case demonstrates that a large PA lesion was resolved through a distinctive diode‑laser and PBMT, achieving significant healing in 10 months.

Introduction: Oral lichen planus (OLP) presents with a burning sensation which may be severe enough to affect the daily activity of the patient. A standard therapy regimen includes the use of topical/systemic corticosteroids. However, many cases show the relapse/recurrence of the lesion and its symptoms frequently after the discontinuation of treatment. Some patients may also develop resistance to corticosteroids or may suffer from the side effects of corticosteroids. Its use is again limited in diabetic patients who are more prone to OLP. Methods: We report six OLP cases (Three were diagnosed as recalcitrant erosive lichen planus) presenting with a complaint of oral burning condition which severely affected their quality of life. Results: Following photobiomodulation (PBM), all cases had complete remission of burning sensation and healing of ulceration and have shown no recurrences in the past 6 months, making PBM an ideal choice for the management of oral burning conditions. Conclusion: PBM is a promising non-invasive treatment modality, which has instantaneous effects on reducing burning sensation in all forms of OLP, even in recalcitrant cases, without any side effects. It does have proven analgesic, anti-inflammatory, and healing effects.

Introduction: Androgenic alopecia (AGA) is the most prevalent form of hair loss, affecting both males and females. Current treatment modalities show varying degrees of efficacy, including high recurrence rates, potential adverse effects, and surgical trauma. The 1927-nm thulium laser has emerged as a promising alternative treatment, offering long-term benefits with good patient tolerability and minimal side effects. Methods: A pre- and post-treatment study design was utilized to assess the efficacy of 1927-nm thulium laser therapy in ten patients with AGA. The procedure involved laser application with a pulse duration of 300 µs, power output of 5 W, and a treatment distance of 0.7 mm, performed without anesthesia. Participants underwent two treatment sessions at two-week intervals, followed by a post-treatment evaluation two weeks after the final session. The primary outcome was the Global Photographic Assessment, based on a 7-point scale evaluating standardized clinical photographs before and after treatment. The secondary outcome was patient satisfaction, measured using the Global Aesthetic Improvement Scale (GAIS). Statistical analysis was conducted using paired t-tests for parametric data and Wilcoxon signed-rank tests for non-parametric data, with a two-tailed significance threshold. Results: A significant clinical improvement was observed at follow-ups 1 and 2 when compared to baseline, with scores (mean±SD) of 1.10±0.316 and 2.00±0.471 (P<0.05). The patients also scored their satisfaction, which showed a significant improvement compared to baseline, with scores of 1.90±0.316 and 3.00±0.471 for follow-ups 1 and 2, respectively (P<0.05). No treatment-related adverse events were reported, and pain levels during the procedure were minimal. Conclusion: Thulium laser therapy is safe and effective in short-term evaluation for hair regrowth in AGA patients.

Introduction: This study aims to evaluate the effectiveness of high-power laser therapy (HPLT) in treating myofascial trigger points (MTrPs) in the upper trapezius muscle, a key contributor to myofascial pain syndrome. Methods: This randomized controlled trial enrolled 40 participants with clinically confirmed active MTrPs in the upper trapezius muscle. Participants were randomly allocated to either the HPLT group or the control group. Both groups received ten treatment sessions over a two-week period. The high-power laser group was treated using a 15-watt laser device (810/980 nm wavelengths), while the control group received routine physiotherapy. Outcomes (Visual Analog Scale, neck disability, cervical range of motion) were assessed before and after the intervention. Results: Significant improvements were observed in both groups, with the HPLT group showing superior outcomes. Pain intensity in the laser group declined by 4.06 points (6.39±1.65 and 2.23±1.24 before and after the intervention, respectively) compared to 2.33 (7.11±1.88 and 4.78±2.18 before and after the intervention, respectively) in the control group (P<0.001). The Neck Disability Index also showed a more pronounced reduction in the laser group (18.35±6.19 and 6.15±3.64 before and after the intervention, respectively) compared to the control group (21.90±7.49 and 15.50±9.09 before and after the intervention, respectively) (P<0.001). Although both groups showed improved cervical side-bending range of motion (ROM), no significant difference was noted (P>0.05). Conclusion: High-power laser therapy provided significant pain relief and functional neck improvement for individuals suffering from upper trapezius MTrPs. These findings contribute to the growing body of evidence supporting the use of HILT as a viable therapeutic modality for musculoskeletal pain, particularly MTrPs.