Lasers in Medical Science最新文献

In this article, we aim to evaluate the effects of photobiomodulation on mitochondria quantity, biogenesis, and mitophagy-associated genes in breast cancer (BC) cells. Both models were irradiated with a low-power infrared laser (880 nm, 150 mW) and amber LED (617 nm, 1500 mW), alone or simultaneously. We evaluated the mRNA expression of PINK1 and PGC-1α genes, and the mitochondrial number was assessed based on the ratio of mitochondrial DNA/genomic DNA (mtDNA/gDNA). No significant difference was observed in the mtDNA/gDNA ratio comparing the low-power infrared laser (LPIL) and LED-irradiated groups to their control counterparts. Similarly, no difference was observed in the mRNA levels of PINK1 and PGC-1α of the irradiated group with an LPIL and LED alone or in combination. In conclusion, PBM with LPIL and LED did not alter the mtDNA/gDNA ratio nor modulate the mRNA levels of the genes related to mitophagy and biogenesis in BC cells.

The aesthetic understanding has found its place in dental clinics and prosthetic dental treatment. Determining the appropriate prosthetic tooth color between the clinician, patient and technician is a difficult process due to metamerism. Metamerism, known as the different perception of the color of an object under different light sources, is caused by the lighting differences between the laboratory and the dental clinic. The traditional trial-error color determination method, coupled with the high cost of instrumental color value determination, has prompted the need for alternative technologies. The integration of AI technologies into dental practices aims to minimize errors in tooth shade assessment, reduce equipment usage, eliminate the impact of clinic lighting on color detection, and decrease costs for patients, dentists, and laboratories. In this study, a machine learning (ML) based approach that can correctly detect tooth shade even under different clinical lights has been developed. A dataset consisting of 580 dental images taken under four different clinical lights and with five repetitions was created using the Vita color shade guide. Experimental studies were performed using the HSV color space, 6 different ML algorithms and color histograms. As a result, 97.93% accuracy rate was achieved by using cross-validation (cv = 5) in the classification of 29 color values ​​independent of clinical lights. It has been shown that the tooth colors can be determined with high accuracy using ML algorithms and metamerism can be prevented.

This systematic review aimed to compare postoperative pain in endodontic treatments using PIPS Er: YAG laser-activated irrigation (LAI) versus conventional needle irrigation. An electronic search was conducted to identify randomized clinical trials (RCT) investigating postoperative pain in patients who underwent root canal treatments in permanent teeth using PIPS Er: YAG laser-activated irrigation or conventional needle irrigation. Two reviewers performed study selection, data extraction, risk of bias assessment (RoB 2.0 tool), and the certainty of evidence (GRADE). The meta-analyses were conducted using Review Manager software (p ≤ 0.05). The mean difference (MD) was chosen as the effect measure, and a random-effect model was employed, along with a 95% confidence interval (CI). The search identified 2864 records, and after selecting, three RCTs were included in the quantitative analysis. The meta-analysis showed a difference in postoperative pain according to the evaluation time. The subgroup meta-analysis revealed that the PIPS Er:YAG showed a significant reduction in the postoperative pain in the 48 hours (MD = -0.78; 95% CI [-1.39, -0.17]; p = 0.01; I² = 69%) compared to the control group. However, no statiscally significant results were found when assessing postoperative pain after 1, 3 and 7 days (95% CI; p > 0.05). The PIPS Er: YAG laser-activated irrigation reduced postoperative pain at 2 days following primary endodontic treatment. However, the certainty of the evidence is low and further RCTs are needed to confirm these results and avoid bias and confounding factors. Registration: PROSPERO registration number: CRD42023432499.

Skin flap transplantation is a conventional wound repair method in plastic and reconstructive surgery, but infection and ischemia are common complications. Photobiomodulation (PBM) therapy has shown promise for various medical problems, including wound repair processes, due to its capability to accelerate angiogenesis and relieve inflammation. This study investigated the effect of red and blue light on the survival of random skin flaps in methicillin-resistant Staphylococcus aureus (MRSA)-infected Sprague Dawley (SD) rats. Forty male SD rats were divided into control and light-emitting diode-red and blue light-treated (LED-RBL) groups at a ratio of 1:1 and a McFarland flap procedure was performed, which was subsequently infected with MRSA strains. After 7 days, the appearance and survival of the flaps were evaluated. The microvascular density was determined by hematoxylin and eosin (HE) staining. The expression levels of vascular endothelial growth factor (VEGF), hypoxia inducible factor 1α (HIF-1α), phosphatidylinositol 3-kinase (PI3K), and protein kinase B (normally expressed as AKT) were detected by immunohistochemistry. The flap survival rate and microvascular density in the LED-RBL group were significantly higher than those in the control group (P < 0.05). In addition, the VEGF, HIF1-α, PI3K, and AKT levels were significantly higher in the LED-RBL group compared to the control group (P < 0.05). Red and blue light increased the survival area of the infected flap in rats by promoting angiogenesis, relieving oxidative stress, and reducing bacterial loads, indicating that PBM therapy is a convenient, simple, analgesic, and safe treatment intervention in promoting the survival rate of transplanted flaps after wound repair surgery.

As photobiomodulation is growing in the dental field the aim of this prospective, two-arm clinical trial was to assess the radiographic changes for chronic periapical bone lesions related to mandibular molars after primary root canal therapy with or without applying Diode laser on soft tissue. The samples were randomly divided into a Laser group and a mock laser (ML) group. Preoperative CBCT images were compared 12 months later with postoperative CBCT to gauge the changes in the volume of the bony lesion by two observers. The kappa coefficient was calculated to assess the intra-observer agreement. Data were presented as median, mean, and standard deviation (SD) values. For parametric data (age), a Student's t-test was used. Qualitative data (Gender) was presented as frequencies and percentages and then analyzed by Chi-square test. The Wilcoxon signed-rank test was used to compare CBCT measurements pre- and post-treatment. The significance level was set at P ≤ 0.05. The collected data in this study showed that there was no statistically significant difference between median volumes of the periapical lesion in the Laser and ML groups (P-value = 0.564, Effect size = 0.237) and (P-value = 0.452, Effect size = 0.310), respectively while, there was a statistically significant decrease in the volume of periapical lesion post-treatment within each group (P-value < 0.001). The size of the periapical bony lesion decreased significantly after conventional endodontic treatment whether Laser was applied or not. The study protocol was enrolled as NCT04311905 at www.clinicaltrials.gov database on (17/03/2020) after the approval of the Ethics Committee, Faculty of Dentistry, Ain Shams University (FDASURecID091703).

The most common cause of rotator cuff injury is supraspinatus tendon tears (STTs). High-intensity laser therapy (HILT) has recently emerged as an important conservative treatment option. This study was designed as a randomised controlled trial in patients with partial STTs to compare the effects of HILT with those of ultrasound (US) therapy. Fifty patients between the ages of 18-75, who were diagnosed with partial STT were randomised into two groups using the closed envelope method. They were blinded to group assignment. Group-1 received 3-week HILT program. Group-2 received 3-week US therapy program. HILT and US therapy were carried out by the same physiotherapist. The primary outcome measure was VAS. Secondary outcome measures were Shoulder Pain and Disability Index (SPADI) and supraspinatus tendon thickness (SP) by ultrasonography. Nine patients dropped out of the study leaving 41 (Group-1, n = 20; Group-2, n = 21) patients for analysis. There was no significant difference between the groups before treatment in terms of age, body mass index values, gender, affected side, smoking, comorbidities, STT, VAS and SPADI values. VAS and SPADI values ​​decreased significantly in both groups at the 4th and 12th weeks. However, VAS and SPADI values ​​at the 4th and 12th weeks were significantly lower in the HILT group than in the US group. Cohen's d analysis revealed large effect sizes at the 4th and 12th weeks favoring the HILT group. There was no significant change in SP within and between groups at any time points. The findings show that HILT is superior to US treatment in reducing pain and improving function and quality of life in the long term. Both treatment methods did not affect SP. Clinical Trials ID: NCT06637410.

Currently, clinical practice has demonstrated various applications for systemic laser photobiomodulation (PBM). In recent years, an increasing number of studies have been highlighted in the literature; however, they differ in their application methods, which can be intravenous, referred to as ILIB (intravascular laser irradiation of blood), or transdermally, recently termed VPBM (vascular photobiomodulation). This review aimed to compile all findings on these techniques and critically discuss their results. A search for articles was conducted in the PubMed, Scopus, and Web of Science databases using Medical Subject Headings (MeSH) to select descriptors with the boolean operators "AND/OR." After applying inclusion and exclusion criteria, 37 articles were selected. Of these, 19 studies discussed the use of systemic PBM with intravenous application, and 7 studies reported transcutaneous application. Regarding clinical studies, 28 studies addressed the application of the techniques in respiratory, cardiovascular, metabolic, neurological, and musculoskeletal conditions. For preclinical studies, 9 articles primarily discussed the application of systemic PBM in pulmonary and musculoskeletal conditions. Despite the promising results, methodological limitations, and variabilities in studies on systemic laser PBM prevent the categorical assertion of its efficacy. It is essential to conduct rigorous new studies to elucidate the mechanisms of action and determine the technique's efficacy.

The aim of the study was todescribe the clinical features, optical coherence tomography (OCT) and fundus autofluorescence (FAF) imaging in patients with choroidal and retinal tumors. Ninety eyes of 89 patients with treatment-naive macular, midperipheral, and juxtapapillary choroidal and retinal tumors were retrospectively included in the study. All patients underwent a complete ophthalmic examination, B-mode ultrasonography, OCT, and FAF imaging. OCT and FAF images taken at the time of diagnosis were reviewed retrospectively. Choroidal nevus (CN), choroidal malignant melanoma (CMM), optic disc melanocytoma (ODM), circumscribed choroidal hemangioma (CCH), and choroidal osteoma (CO) displayed dome-shaped contour on OCT, while choroidal metastases (CM) showed a lumpy bumpy contour. CN had preserved choriocapillaris. Choroidal compression was observed in all choroidal tumors except CCH which showed vascular expansion. CMM was the most common lesion displaying overlying lipofuscin. Intraretinal fluid was seen mostly in CCM and CCH. Subretinal fluid (SRF) was usually observed in CM, CMM, and CCH. Drusen and pigment epithelial detachment (PED) were noted in CN. While the pattern of hyperautofluorescence (hyper-AF) was most marked in CMM, other tumors including CCH and CM occasionally showed similar FAF appearance. Comparing CN and CMM; CN displayed more drusen and PED (p = 0.024 and p = 0.037 respectively) and CMM showed more SRF, intraretinal fluid, and shaggy photoreceptor (p = 0.040, p < 0.001, and p < 0.001 respectively). CN displayed more hypo-AF and iso-AF (p < 0.001) while CMM showed significantly more diffuse and patchy hyper-AF (p < 0.001). Characteristic findings in OCT and FAF guide clinicians in the differential diagnosis of choroidal and retinal tumors and allow for earlier detection and improved treatment outcomes.

Hypertrophic scars (HTSs) are the result of an abnormal healing process resulting from burns and other severe traumas. The symptoms of that condition include skin irritation, discomfort, and itching. This study aimed to assess the efficacy of fractional carbon dioxide (CO₂) laser therapy alone or with triamcinolone or 5-fluorouracil (FU) in the treatment of early post-burn hypertrophic scars (HTSs) that develop during the first 6 months after the injury. A prospective, randomized, single-blind comparative study was conducted on 30 patients aged 16-65 with hypertrophic scars (HTS) resulting from burns. Patients had no prior treatment for their scars. We randomly assigned participants to one of three groups: Group A received fractional CO₂ laser therapy alone, Group B received fractional CO₂ laser therapy with topical 5-fluorouracil, and Group C received fractional CO₂ laser therapy with topical triamcinolone acetonide. All treatment groups showed significant improvements (p < 0.05) in overall scar severity and height. Patients in Group C (fractional CO₂ laser + triamcinolone) demonstrated significant improvements in scar pliability, height, and pigmentation (p < 0.05). In contrast, patients in Group B (fractional CO₂ laser + 5-FU) showed significant reductions in scar vascularity, pliability, and height following treatment (p < 0.05). While all groups reported minor changes in pain and itching, there were no significant differences in these symptoms between Group B and Group C. HTSs of this trial revealed reductions in overall scar surface area and thickness and improvement of pliability and pigmentation; however, there was not statistically significant difference between the effect of 5-fluorouracil and triamcinolone acetonide (TAC), suggesting that neither drug offers better efficacy over the other. Level I, singleblinded randomized control study.

This brief report aimed to investigate the optical absorbance spectra of normal, dysplastic, and malignant epithelial cell lines under normal and nutritional stress conditions. HaCAT (keratinocyte), DOK (oral dysplastic), and oral squamous cell carcinoma (OSCC) cell lines (CA1, Luc4, SCC9) were evaluated regarding their optical absorbance after culture with 0-10% fetal bovine serum. Absorbance measurements indicated that HaCAT under serum starvation exhibited higher absorbance at blue (430 nm) and near-infrared (906 nm) wavelengths. DOK showed absorption at 440 nm and 945 nm. OSCC cells showed absorption peaks at blue (400-428 nm) and near-infrared. These findings highlight the importance of tailoring PBM parameters to individual needs to achieve optimal absorption and effectiveness. Moreover, the higher absorption peaks in the blue region support further studies to elucidate the potential use of blue light in oral dysplastic lesions and OSCC.