Lasers in Medical Science最新文献

To evaluate the cutting accuracy and thermal damage in oral soft tissue using different cutting techniques. Sixty specimens of sheep oral mucosa tissue, with the dimensions of 2.0 cm in length and 1.5 cm in width were prepared and divided into six groups (n = 10) representing different cutting technique. Incisions were made by sectioning each specimen using the 2000 nm continuous-wave (CW) silica based thulium-doped fibre (TDF) laser (Group A), the 1550 nm CW silica based Erbium/Ytterbium-doped fibre (EYDF) laser (Group B), electrosurgery (Group C), 980 nm diode laser (Group D), 2000 nm ultrashort-pulsed (USP) silica based TDF laser (Group E), and the scalpel (Group F or control group). Each specimen was measured for average roughness value (Ra) and thermal damage, reported as mean and standard deviation. A one-way ANOVA with post-hoc Tukey's HSD test was performed to determine significant differences among six groups, with a significance level set at p < 0.05. Among the energy-based groups, the 2000 nm USP silica based TDF laser (Group E) exhibited the lowest Ra (1.22 ± 0.71 μm) and minimal thermal damage (9.85 ± 4.01%). In contrast, the highest Ra (4.82 ± 1.36 μm) was observed in the electrosurgery (Group C), while the highest thermal damage (16.73 ± 4.57%) was recorded in the 1550 nm CW silica based EYDF laser (Group B). One-way ANOVA revealed statistically significant differences among the groups in both average roughness (F = 45.45, p < 0.001) and thermal damage (F = 11.84, p < 0.001). The findings suggest that the 2000 nm USP silica based TDF laser offers superior cutting accuracy with minimal impact of thermal damage, supporting its potential adoption into clinical protocols for oral soft tissue surgery.

This study systematically reviewed the effect of photon induced Photo-Acoustic Streaming (PIPS), compared to Conventional Syringe Irrigation (CSI), on the removal of smear layer and/or debris from root canals. Searches and screening were conducted by two independent reviewers in PubMed/MEDLINE and EMBASE up to August 2025. Eligible studies were in vitro investigations on extracted human teeth evaluating smear layer and/or debris removal using Scanning Electron Microscopy (SEM). A descriptive analysis was performed, and the quality of the studies was assessed by an adapted version of the Joanna Briggs Institute (JBI) checklist. Of 911 screened studies, 14 met the inclusion criteria. PIPS generally showed superior smear layer removal compared with CSI. One study attributed the effect to 20% EDTA rather than the activation technique. Regardless of the irrigant used (distilled water, saline, NaOCl or EDTA), PIPS enhanced smear layer reduction. Removal was more effective in the cervical and middle root thirds than in the apical third. Risk of bias assessment classified 9 articles as medium, 4 as high and 1 as low risk. PIPS appears more effective than CSI in reducing smear layer on root canal walls and can be considered an alternative irrigant activation method. However, heterogeneity among studies limits direct comparisons, highlighting the need for standardized experimental protocols to clarify the effectiveness of PIPS and other techniques. Enhancing smear layer and/or debris removal is critical for disinfection and sealing in endodontics. PIPS shows potential to improve root canal cleanliness compared with CSI.

Background: Low-level laser therapy (LLLT) is a noninvasive method for decreasing fat without surgery. It functions by breaking down fat cells, resulting in a noticeable reduction in body circumference. This study aimed to assess the effects of LLLT in reducing body circumferences.

Methods: A search of four databases (Web of Science, SCOPUS, PubMed, and Cochrane Library) up to September 30, 2025, identified three randomized controlled trials (RCTs) that met the inclusion criteria, in which the outcome was the reduction in body circumferences measured by tape. Quality assessment was done using the Cochrane risk-of-bias tool for randomized trials (RoB2).

Results: The trials included 160 participants and found that LLLT significantly lowered waist circumference by 2.48 cm compared with 0.635 cm in controls. Follow-up assessments performed 2 weeks post-intervention in two studies confirmed sustained improvements. Moreover, in two studies, hip circumference decreased by 4.09 cm versus 0.86 cm in controls, an effects size of -2.2 cm (mean difference = 2.7 cm). Effect size on waist circumference was - 1.9 cm indicating an average decrease in measurement by1.9 cm (mean difference = 2.5 cm). Reduction was also observed in the abdomen and thigh circumferences. Effect sizes across the RCTs ranged from - 0.4 cm to -8.7 cm (P < 0.05).

Conclusion: LLLT promises to achieve localized fat reduction with minimal adverse effects and high patient satisfaction. However, varying treatment protocols and follow-up durations make it challenging to determine optimal parameters and long-term efficacy.

Registration number: CRD42025645438. 19 September 2025.

This study aims to assess the safety and effectiveness of transurethral blue laser prostate vaporization (BVP) for elderly patients (≥80 years) with benign prostatic hyperplasia (BPH), focusing on clinical outcomes, recovery, and complications. A retrospective analysis was performed on 157 BPH patients aged ≥ 80 years who underwent BVP at a single center between May 2023 and May 2025. The patients' general condition was assessed through comorbidities and concurrent surgeries, postoperative outcomes were evaluated through the International Prostate Symptom Score (IPSS), and surgical safety was evaluated based on operative time and postoperative blood tests. The mean age was 83.97 ± 3.63 years, with an average prostate volume of 63.34 ± 34.95 ml. Patients had an average of 2.5 comorbidities, and 26.1% required additional surgical interventions. The average procedure time was 28.2 ± 12.1 min, with a median hospital stay of 9 days. Postoperative IPSS scores decreased significantly to 4.3 ± 3.5. Mild red blood cell loss (hemoglobin decreased by 6.1%, p < 0.001) and a significant inflammatory response (neutrophils increased by 26.5%, p < 0.001) were observed, but no transfusion was needed. Transurethral blue laser prostate vaporization is a safe and effective option for elderly BPH patients with multiple comorbidities, offering significant symptom improvement with minimal postoperative complications.

Vocal fatigue (VF) is a significant occupational burden for professional voice users, such as teachers, for whom rapid and effective interventions remain limited. Photobiomodulation (PBM), a noninvasive therapy that uses low-intensity light to mitigate inflammation and promote tissue repair, is a promising therapeutic strategy. In this study, we investigated the immediate effects of a single PBM session on key acoustic and respiratory parameters in female teachers with VF. In this single-arm, pre-post clinical trial, we enrolled 41 female primary school teachers (age range: 28-40 years) with symptoms of vocal fatigue classified as mild (n = 19), moderate (n = 18), or severe (n = 4). A single 5-minute PBM session was administered to the laryngeal region using a light-emitting diode (LED) device delivering 1 W of optical power across two wavelengths (640 and 940 nm). Acoustic parameters (jitter, shimmer, and connected speech frequency) and respiratory capacity were measured before and immediately after the intervention. In the severe subgroup, jitter decreased (p = 0.005) and mean autocorrelation increased (p = 0.024), while connected speech (p = 0.056) and respiratory capacity (p = 0.058) showed trends toward improvement. In the moderate subgroup, peak flow increased (p = 0.002). No meaningful changes were observed in the mild subgroup. A single session of photobiomodulation therapy resulted in immediate and significant improvements in vocal quality and respiratory function, particularly in teachers with severe vocal fatigue. These findings position PBM as a promising non-invasive tool for rapid vocal rehabilitation in individuals with pronounced phonatory deficits. However, these findings should be interpreted in consideration of several limitations, including the small sample size, particularly in the severe subgroup, the absence of a control group, and the short, immediate follow-up period. The uneven distribution of participants across severity levels may also limit generalizability. Despite these constraints, the pronounced improvement observed in the severe vocal-fatigue subgroup underscores the clinical relevance of PBM as a rapid, non-invasive option for individuals with substantial phonatory impairment.

LED photobiomodulation therapy (PBMT) is widely recognized for its beneficial effects in several clinical conditions; however, its potential in modulating vascular function is not yet fully established. This study aimed to evaluate the application of PBMT by LED (light-emittion diode) using a combined red and near-infrared light spectrum, with a focus on improving the vascular function of the radial artery in vitro. A total of 40 radial artery segments were studied and divided into Four groups of 10 segments, including the control (C), red (R), infrared (IR), and combined red + infrared (R + IR). Prior to light irradiation at wavelengths of 650 nm and 940 nm, vascular function in these segments was pharmacologically inhibited using L-NAME. The drugs phenylephrine, acetylcholine, and sodium nitroprusside were used to determine if irradiation could restore the inhibited vascular functions. Superoxide anion levels, an important reactive oxygen specie (ROS), were measured using a chemiluminescence assay with lucigenin. The bioavailability of nitric oxide was evaluated using a Griess Reagent Kit assay. The vascular inflammation was determined by the Intercellular Adhesion Molecule 1 (ICAM-1) expression. The results indicate that combined PBMT improved vascular function compared to PBMT with isolated light spectra, promoting greater vascular relaxation by increasing nitric oxide by increasing nitric oxide bioavailability and decreasing the superoxide anion production. Additionally, the combined light spectrum and the red spectrum decreased the ICAM-1 expression. Combined spectrum LED photobiomodulation therapy improves vascular function by promoting vasodilation, reducing reactive oxygen species (ROS) production, and attenuating inflammatory responses.

Eyelid laxity is a visible sign of aging that can significantly affect appearance and comfort; however, many patients remain reluctant to undergo surgical blepharoplasty. Monopolar radiofrequency (RF) offers a non-invasive alternative. This study evaluated the efficacy and safety of a 0.25 cm² monopolar RF tip for upper eyelid tightening in Asians. Fourteen subjects received a single session of treatment with a 0.25 cm² tip monopolar RF device. Multiple passes were applied to the upper eyelid and lateral orbital regions. Topical anesthesia was applied 30 min before treatment, and a protective plastic contact lens was used during the procedure. Standardized digital photography, physician assessments, and patient-reported outcomes were obtained at each visit. All subjects demonstrated clinical improvement. At 2 months, 73% of patients reported more than 50% improvement in eyelid tightening, increasing to 86% at 6 months. Physician Global Aesthetic Improvement Scale (GAIS) ratings corresponded to "much improved" at both time-points. Mid-pupillary brow elevation increased by 1.18 mm at 2 months and 1.45 mm at 6 months. Lateral canthal brow elevation increased by 1.23 mm and 1.21 mm, respectively. Superior palpebral crease elevation improved by 0.54 mm and 0.41 mm, while the eyebrow angle decreased by - 4.12° and - 5.67°, indicating a more elevated brow contour. No adverse events were observed. In conclusion, monopolar RF treatment with a 0.25 cm² tip appears to be a safe and effective non-surgical option for upper eyelid tightening in Asians.

To evaluate the efficacy and safety of the combination of the long-pulse 1064 nm neodymium-doped yttrium aluminum garnet (LP1064 nm) laser and picosecond 755 nm alexandrite (P755 nm) laser with a diffractive lens array (DLA) in improving skin photoaging. This prospective, randomized, split-face trial was conducted between April 2024 and February 2025 at two centers. A total of 22 healthy volunteers with facial photoaging symptoms aged 30-65 years were enrolled. The full face was treated with the LP1064 nm laser, and one side was treated with the P755 nm laser with DLA for three sessions at 1-month intervals. Efficacy and safety were assessed before each treatment and 1, 3, and 6 months after treatment. The primary outcome was the Global Aesthetic Improvement Scale (GAIS) score. A total of 21 patients completed the study. The combined treatment side demonstrated further improvement in GAIS scores compared with the monotherapy side at 3 (85.7% vs. 66.7%) and 6 months (66.7% vs. 57.1%). Significant changes in the facial regions were observed. Volumetric analysis using 3D assessment revealed that the combined treatment had a more pronounced effect on the nasolabial folds and suborbital areas. VISIA analysis found significantly improved pigmentation and pore size at 1 and 3 months after treatment. No adverse events were observed on either side during or after treatment period. The combination of the LP1064 nm and P755 nm lasers with DLA can enhance skin rejuvenation by addressing the structural and pigmentary aspects of photoaging. These preliminary findings support the safety and efficacy of this combination approach. Further studies are needed to optimize this approach.

To evaluate and compare the effect of 15, 20, 45 and 60 s of diode laser irradiation on the In Ovo Chick Embryo Yolk Sac Membrane (YSM) for Angiogenic differentiation. 15 fertile White Leghorn eggs incubated under controlled conditions were used in the study. Eggs were randomly assigned to five groups (n = 3) and exposed to 980 nm diode laser (0.7 W) for 15, 20, 45 and 60 s, with a control group receiving no irradiation. On day 10, the chorioallantoic membrane (CAM) vasculature was imaged and analysed using IKOSA CAM assay software to quantify blood vessel branching. Statistical analysis was performed using one-way ANOVA followed by Tukey's post hoc test. The mean values of vascular branching points, total vessel length, and vessel area showed statistically significant differences across all groups (p < 0.02, < 0.001, and < 0.04, respectively). Intergroup comparisons revealed significant increases in branching points for the 45-seconds (p < 0.04) and 60-seconds (p < 0.003) groups versus control, and between 15- and 60-seconds (p < 0.006), and 20- and 60-seconds (p < 0.02) groups. Total vessel length differed significantly between control and the 15-second (p < 0.02), 45-seconds (p < 0.001), and 60-second (p < 0.04) groups. For vessel area, a significant increase was noted in the 45-seconds group compared to control (p < 0.04). These results suggest that diode laser irradiation significantly enhances angiogenesis, with 45 s producing the most pronounced effect across all parameters. Diode laser irradiation enhances angiogenesis, with 45 s being the optimal exposure time for angiogenic differentiation. These findings suggest that highlight LLLT may accelerate healing and tissue repair, warranting further research for clinical applications.