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The safety and efficacy of laser hair removal have been well established through many clinical studies and through clinical use over the past 25 years. A laser hair removal device that protects the epidermis by utilizing cryogen spray cooling (CSC) is widely used internationally. In darker skin types, post-inflammatory hyperpigmentation (PIH) can occur after laser hair removal. In particular, laser hair removal with CSC is known to cause crescent-shaped or ring-shaped PIH. In this experiment, we report a visualization of this PIH mechanism. The laser used in this experiment is a 755-nm-long-pulsed alexandrite laser. Graph paper was treated with this laser to assess for thermal damage. We investigated changes in thermal damage due to differences in laser spot size, fluence output, and laser beam angle in relation to the graph paper. When using a spot size of 18 mm, we observed that higher fluences caused crescent-shaped thermal damage on the margins of the treated graph paper. It was also confirmed that when the hand piece is not held perpendicular to the skin, the laser-treated area is expanded and the CSC range is narrowed. These factors caused the area of thermal damage to widen. This widening causes ring-shaped thermal injury, leading to PIH. We treated graph paper using a hair removal laser with CSC to investigate the mechanism of crescent or ring-shaped thermal damage. Laser treatment on graph paper is effective as a test for defects in the CSC device. Factors that cause inadequate cooling, which leads to PIH, are large spot size, high fluence, not holding the laser hand piece perpendicular to the skin, and malfunctioning of CSC device. [ABSTRACT FROM AUTHOR]

Presents several abstracts of research papers presented at the 19th International Congress Laser Medicine: Laser Florence 2004 on October 28-30 in Florence, Italy.

The objective of this study was to evaluate the bleaching effect of light sources with various wavelengths using 30% hydrogen peroxide (HP) in vitro. The hematoporphyrin-stained paper was bleached with HP and irradiated for 10 min using LED light sources with 265, 310, 365, 405, or 450 nm respectively. In control group, HP was applied for 10 min without light irradiation. The bleaching procedure was repeated two times. The L*a*b* values of the samples before bleaching and after each bleaching step were measured using a colorimeter. Color changes of specimens were then calculated and statistically analyzed. There was an interaction between light sources and time of irradiation in the color change (p < 0.05). Time and light sources significantly affected ΔE and ΔL (p < 0.05). The light source of 256 nm showed the highest bleaching effect over time followed by that of 310 nm, which were statistically different from other groups (p < 0.001). The 365 nm, 450 nm groups, and control group showed low bleaching effect visually with no significant differences in ΔE and ΔL (p > 0.05). It was concluded that the wavelengths of the light sources affected the bleaching by HP. The 310-nm light can be a potential source for bleaching.

This paper introduces a novel application of the laser speckle technique in dentistry, focusing on assessing the efficiency of dental excavation methods used to remove decayed tooth structure. The aim is to evaluate the efficiency of two chemo-mechanical agents and the high-speed drill using the laser speckle technique, which offers objective, non-invasive, and real-time evaluation capabilities. Extracted human primary molars with active occlusal carious lesions were sectioned into three parts, with each part allocated to one of three groups: Group 1 (Brix3000®), Group 2 (Papacarie DUO®), and Group 3 (High-speed drill mechanical caries removal). Caries removal was performed using the designated agent or method for each group. After caries excavation, speckle imaging using a 632.8 nm laser was conducted. Additionally, SEM was used to acquire micro-photographs of the surface morphology of the treated samples. The findings reveal insights into the comparative efficiency of the three dental excavation agents and methods using the laser speckle technique. The speckle parameters extracted from speckle patterns generated by treated teeth provide valuable information for evaluating the performance of the excavation methods. The scanning electron microscopy images also offer detailed visual evidence to support the analysis. This paper demonstrates the potential of the laser speckle technique for assessing the efficiency of dental excavation methods. The objective, non-invasive, and real-time evaluation provided offers advantages over subjective visual assessment and manual measurements. [ABSTRACT FROM AUTHOR]

This study aimed to comparatively evaluate the disinfecting potential of sodium hypochlorite, diode laser, and photodynamic therapy in non-vital teeth with or without periapical rarefaction. Forty-five patients with the diagnosis of pulp necrosis with apical rarefaction were randomly assigned to three groups (n = 15) based on the disinfection protocol. Access cavities were prepared and pre-instrumentation microbial samples were taken using a paper point. Working length determination followed by cleaning and shaping with rotary files was performed. The canals were lubricated with ethylenediaminetetraacetic acid (EDTA) during instrumentation and finally rinsed with copious amounts of saline. Canals in group 1 were irrigated with 5 mL of 5.25% NaOCl, those in group 2 received irradiation with 808-nm diode laser (30 s, 7W), and those in group 3 were soaked with methylene blue photosensitizer (5 min) before irradiation with 660-nm diode laser (3 min). Post-disinfection microbial samples were collected using a paper point. Pre- and post-disinfection live bacterial counts were analyzed using a flow cytometer. The data were statistically analyzed using one-way ANOVA and Student's t-test. Comparison of pre-instrumentation mean live bacterial count showed no significant difference between the groups (p > 0.05). The mean live bacterial count post-disinfection was 41.07%, 46.99%, and 34.45% in groups 1–3 respectively. A significant reduction in the bacterial count was seen following disinfection in all the groups (p < 0.05). It can be concluded that both diode laser and photodynamic therapy were equally effective as 5.25% NaOCl in reducing the bioburden in root canals. Trial registration: CTRI/2018/03/012667. [ABSTRACT FROM AUTHOR]

The most common photobiomodulation parameters used to aid in the treatment of diabetic foot ulcers were investigated in this paper. The databases MEDLINE, LILACS, MEDCARIB, PAHO-IRIS, and WHOLIS were searched with the following descriptors: diabetic foot ulcers AND low-level laser therapy OR low-level therapy AND wound healing; this search was conducted from January of 2014 to December of 2019. Inclusion criteria were randomized clinical trials on humans. Exclusion criteria were systematic reviews, literature reviews, studies with animals, studies lacking photobiomodulation parameters, and studies with non-diabetic individuals. The Jadad scale was used in order to analyze the methodological quality of the matching papers. There were seventeen studies found on PubMed and four on LILACS. Among these, seven were selected, according to the inclusion and exclusion criteria. Two out of the seven matching studies obtained a high score, and five obtained a low score, on the Jadad scale. The studies settled on the use of 600-nm and 800-nm wavelength spectrum. Most of the analyzed papers on photobiomodulation on diabetic foot ulcers did not describe the detailed parameters in their methodology. None of the studies featured the maximum score with regard to the Jadad scale for methodological quality. The relations of energy versus wavelength and power versus wavelength were divergent among the parameters on the papers. Therefore, it is necessary to analyze the parameters for an optimized power value in order to improve the results of the treatment. [ABSTRACT FROM AUTHOR]

Vital pulp therapy (VPT) is primarily intended to preserve the vitality of pulp tissues, which have been exposed for any reason. Various materials and techniques have been proposed to improve treatment outcomes, including the use of lasers. This study aimed to review the histological results of different dental lasers including low-level lasers, carbon dioxide (CO2), erbium-doped yttrium aluminum garnet laser (Er:YAG), neodymium-doped yttrium aluminum garnet (Nd:YAG), erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) lasers, and diode lasers for VPT. This focused review included a comprehensive electronic search of Scopus, MEDLINE, Web of Science, and Google Scholar databases from 2000 to 2022 by two independent investigators. Different combinations of keywords were used, and reference mining of related papers was done. The review included studies related to histologic evaluation of laser-assisted vital pulp therapy that stated the laser parameters that were used. Articles with radiographic or clinical assessments or articles lacking necessary data were excluded. Non-English articles were excluded unless their abstract was in English and encompassed the necessary data. Most studies indicated the efficacy of lasers for reduction of inflammation, acceleration of healing, and increasing the thickness of dentinal bridge. According to the evidence, lasers used in combination with pulp capping agents are beneficial to enhance the success rate of VPT. [ABSTRACT FROM AUTHOR]

Medicinal plants play a vital role in herbal medical field and allopathic medicine field industry. Chemical and spectroscopic studies of Taraxacum officinale, Hyoscyamus niger, Ajuga bracteosa, Elaeagnus angustifolia, Camellia sinensis, and Berberis lyceum are conducted in this paper by using a 532-nm Nd:YAG laser in an open air environment. These medicinal plant's leaves, roots, seed, and flowers are used to treat a range of diseases by the locals. It is crucial to be able to distinguish between beneficial and detrimental metal elements in these plants. We demonstrated how various elements are categorized and how roots, leaves, seeds and flowers of same plants differ from each other on the basis of elemental analysis. Furthermore, for classification purpose, different classification models, partial least square discriminant analysis (PLS-DA), k-nearest neighbors (kNN), and principal component analysis (PCA) are used. We found silicon (Si), aluminum (Al), iron (Fe), copper (Cu), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), manganese (Mn), phosphorous (P), and vanadium (V) in all of the medicinal plant samples with a molecular form of carbon and nitrogen band. We detected Ca, Mg, Si, and P as primary components in all of the plant samples, as well as V, Fe, Mn, Al, and Ti as essential medicinal metals, and additional trace elements like Si, Sr, and Al. The result's findings show that the PLS-DA classification model with single normal variate (SNV) preprocessing method is the most effective classification model for different types of plant samples. The average correct classification rate obtained for PLS-DA with SNV is 95%. Moreover, laser-induced breakdown spectroscopy (LIBS) was successfully employed to perform rapid, sensitive, and quantitative trace element analysis on medicinal herbs and plant samples. [ABSTRACT FROM AUTHOR]

The optical scattering coefficient (μs) in the dermis layer of human skin obtained with optical coherence tomography (OCT) has shown to have a strong correlation with the blood glucose concentration (BGC), which can be used for noninvasive BGC monitoring. Unfortunately, the nonhomogeneity in the skin may cause inaccuracies for the BGC analysis. In this paper, we propose a 2D correlation analysis method to identify 2D regions in the skin with μs sensitive to BGC variations and only use data in these regions to calculate μs for minimizing the inaccuracy induced by nonhomogeneity and therefore improving the accuracy of OCT-based BGC monitoring. We demonstrate the effectiveness of the 2D method with OCT data obtained with in vivo human forearm skins of nine different human subjects. In particular, we present a 3D OCT data set in a two-dimensional (2D) map of depth vs. a lateral dimension and calculate the correlation coefficient R between the μs and the BGC in each region of the 2D map with the BGC data measured with a glucose meter using finger blood. We filter out the μs data from regions with low R values and only keep the μs data with R values sufficiently high (R-filter). The filtered μs data in all the regions are then averaged to produce an average μs data. We define a term called overall relevancy (OR) to quantify the degree of correlation between the filtered/averaged μs data and the finger-blood BGC data to determine the optimal R value for such an R-filter with the highest obtained OR. We found that the optimal R for such an R-filter has an absolute value (|R|) of 0.6 or 0.65. We further show that the R-filter obtained with the 2D correlation method yields better OR between μs and the BGC than that obtained with the previously reported 1D correlation method. We believe that the method demonstrated in this paper is important for understanding the influence of BGC on μs in human skins and therefore for improving the accuracy of OCT-based noninvasive BGC monitoring, although further studies are required to validate its effectiveness. [ABSTRACT FROM AUTHOR]

Although the standard treatment for periodontal disease is based on scaling and root planing (SRP), the use of antimicrobial photodynamic therapy (aPDT) has been studied as a complement to obtain better clinical results. The purpose of this study was to evaluate the effect of aPDT as adjuncts to SRP, compared with SRP alone, on clinical parameters of chronic periodontal patients. Only randomized controlled trials with at least 3-month follow-ups, of SRP alone and in association with aPDT, were included. The MEDLINE (PubMed), Google Scholar, and LILACS databases were searched for articles published up to July 2020. Random-effects meta-analyses were conducted for clinical attachment level (CAL) and probing pocket depth (PPD) change after treatment. Of 141 potentially relevant papers, 22 were included. The association between SRP and aPDT promoted a significant CAL gain and PPD reduction. Periodontal treatment was partially improved by aPDT, and a favorable effect of indocyanine green–mediated aPDT was observed, and high concentrations of phenothiazine chloride presented clinical improvement as well. [ABSTRACT FROM AUTHOR]

Precise knowledge about light propagation in biological tissues is necessary for accurate diagnostics and effective therapies utilizing optical technologies. In the current paper, the Monte Carlo simulation is applied to study light dispersion in normal and cancerous breast after irradiating to different laser beam shapes. Two distinct laser wavelengths (800–1100 nm) with planar and Gaussian shapes were employed. The spatially resolved steady-state diffuse reflectance of normal tissue and tumor was investigated using Monte Carlo simulation method via MCML and MCXLAB computations. The diffusion equation was solved to simulate the fluence rate at the tissue surface based on the optical parameter values (i.e., scattering and absorption coefficients). The results confirm differences in diffuse reflectance and optical fluence distribution between the normal and tumor tissues at each wavelength. Tissue optical parameters and the utilized laser beam shape control the distribution of the fluence rate within tissues. Therefore, offering visual representations of these distributions can provide a secure visual route for biological diagnostics. [ABSTRACT FROM AUTHOR]

Elimination of Enterococcus faecalis is vital during root canal treatment. Owing to their antimicrobial properties, laser-activated nanoparticles (NPs) have been used in root canal irrigation in the recent past. The aim of this review is to conduct a qualitative analysis of the published data evaluating the antibacterial efficacy of laser-activated nanoparticles in the elimination of E. faecalis from the root canal system. Considering all the papers published till August 2022, a search of the databases PubMed, SCOPUS, and EBSCOhost was conducted. All the articles that were published in English were included. The review process was guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist. The risk of bias was assessed after the extraction of the data. After screening the distinguished 51 studies according to the inclusion criteria, five in vitro studies were included for the systematic review. A systematic review of the selected studies showed a positive impact on E. faecalis load reduction following irrigation with nanoparticles irradiated using lasers. Laser-activated nanoparticles have shown superior antibacterial efficacy compared to conventional irrigation techniques and may be used as an alternative for root canal disinfection. [ABSTRACT FROM AUTHOR]

The purpose of this study is to assess the laser effect in root canal disinfection and periapical healing of endodontically treated teeth from patients with asymptomatic apical periodontitis. This study was performed as a randomized clinical trial. Thirty patients were selected according to the inclusion/exclusion criteria. Fifteen patients received the root canal retreatment (RCR) combined with 980-nm diode laser irradiation (LI). The canals were irrigated with saline solution and gently dried with paper points, keeping the dentin partially moist. The irradiation was performed using a 320-µm-diameter fiber in helicoidal movements (pulsed mode, power output of 1.5 W, 100 Hz for 20 s). The other 15 patients received the RCR with placebo irradiation (PI). Microbiological samples were taken in three periods: S1, after the filling material removal (baseline); S2, after laser or placebo irradiation (LI or PI); and S3, after the RCR followed by laser or placebo. The samples were submitted to the total microbial and E. faecalis counting. The periapical radiographic healing was analyzed after 3, 6, 9, and 12 months. Microbiological data (CFU/mg) were analyzed by ANOVA and Tukey’s test (P < 0.05), and the repair by Mann–Whitney test (P < 0.05). In S2, the laser provided 42.44% microbial reduction and 53.14% of E. faecalis, different from the placebo that had no reduction, and 4.85% for Enterococcus (P < 0.05). In S3, the bacterial counts decreased without differences between groups. No differences in healing were found at 3 months. However, diode laser facilitated the repair from 3- to 12-month follow-up (P < 0.05) and had 45% more healed cases than placebo. Diode laser provided an antimicrobial effect before the biomechanical preparation but was not synergistic in RCR. It improved the periapical healing during follow-up. [ABSTRACT FROM AUTHOR]

Identification and classification of surrounding neck tissues are very important in thyroid surgery. The advantages of optical coherence tomography (OCT), high resolution, non-invasion, and non-destruction make it have great potential in identifying different neck tissues during thyroidectomy. We studied the automatic classification for neck tissues in OCT images based on convolutional neural network in this paper. OCT images of five kinds of neck tissues were collected firstly by our home-made swept source (SS-OCT) system, and a dataset was built for neural network training. Three image classification neural networks: LeNet, VGGNet, and ResNet, were used to train and test the dataset. The impact of transfer learning on the classification of neck tissue OCT images was also studied. Through the comparison of accuracy, it was found that ResNet has the best classification accuracy among the three networks. In addition, transfer learning did not significantly improve the accuracy, but it can somewhat accelerate the convergence of the network and shorten the network training time. [ABSTRACT FROM AUTHOR]

In this paper, breast cancer patients were monitored throughout their chemotherapy treatments (CHT), with blood serum sample Raman spectroscopy and multivariate analysis, approximately for a year. First of all, we discriminate between healthy and clinically diagnosed breast cancer patients. Breast cancer detection in terms of sensitivity and specificity were 87.14% and 90.55% respectively. Although no shifts of peaks in mean spectrum of samples from breast cancer patients were found with respect to the mean spectrum from control patients, some peaks did show clear differences in intensity, the greatest disparities found at 509, 545, 1063, 1103, 1338, 1556, 1083 and 1449 cm− 1 are associated with amino acids and phospholipid, 1246 and 1654 cm− 1, corresponding to amide III and I, respectively. Other peaks of interest encountered at 450, 661, 890, 917 and 1405 cm− 1 are associated to glutathione. Then, 6 breast cancer patients were monitored during their chemotherapy treatments, the results were in complete correspondence with their medical records, enabling a detailed study of the evolution of each patient's cancer. A special interest arose in the possible correlation between the intensity of Raman peak, 450 cm− 1, corresponding to glutathione and evolution of cancer throughout CHT, i.e., glutathione appears to be a good candidate as breast cancer biomarker. The results confirmed that Raman spectroscopy and PCA are, not only a good support to current breast cancer detection techniques, but could also be excellent techniques to monitor more efficiently breast cancer patients undergoing CHT, using blood serum samples which are a lot less invasive than other methods. [ABSTRACT FROM AUTHOR]

Treatment of pigmented lesions is one of the major challenges of laser and cosmetic practitioners. The most common pigmented lesions that are treated by lasers are melanocytic nevi, ephelides, solar lentigines, and café au lait macules. Melanin absorbs different wavelengths (500–1100 nm); thereby, treatment of various pigmented lesions requires the application of lasers with different wavelengths. Choosing the most appropriate type of laser depends on various factors such as the chromophore and the location of a specific lesion in the skin. In this paper, we aim to review the most efficient laser treatment protocols for each pigmented skin lesion and compare their efficacy in each part based on the previous studies. [ABSTRACT FROM AUTHOR]

. A study was conducted to evaluate the antibacterial effect of yellow He-Ne laser irradiation with crystal violet solution (CV) on Porphyromonas gingivalis (P.g.). Paper points were soaked with a P.g. suspension (109 ml) with 0.8 mg/l CV added, laser-irradiated for 60 s (laser group), and implanted subcutaneously on the back of rats. Three additional groups were studied: CV group: the paper point was soaked with the P.g. suspension plus 0.8 mg/l CV, but laser irradiation was not performed; P.g. group: the paper point was soaked with the P.g. suspension only and laser irradiation was not performed; control group: the paper point was soaked with sterilised isotonic sodium chloride solution and laser irradiation was not performed. Seven days after implantation, block sections of all implanted sites were examined histologically. The abscess area in the laser group was smaller than in the P.g. group or CV group, but larger than in the control group. The number of inflammatory cells was greatest in the P.g. and CV groups, with fewer in the laser group and still fewer in the control group. The results indicate that a yellow He-Ne laser with 0.8 mg/l CV solution exerts an antibacterial effect in vivo. [ABSTRACT FROM AUTHOR]

The disinfection of root canal through minimally invasive access cavity remains questionable. This in vitro study compared the effectiveness of three disinfection measures including conventional irrigation, ultrasonic assisted irrigation, and erbium:yttrium-aluminum-garnet (Er:YAG) laser assisted irrigation through conventionally or minimally invasive access. Sixty-six extracted maxillary first molars were randomly divided into group 1 conventionally invasive access group (CIA) and group 2 computer-guided minimally invasive access group (MIA). Each group was further randomly divided into three subgroups, (A) conventional irrigation (CI), (B) passive ultrasonic agitation (PUI), and (C) Er:YAG laser activated irrigation (LAI). Enterococcus faecalis (E. faecalis) infection model was established inside all root canals after instrumentation was performed up to ProTaper Universal F2. After various disinfection methods, microbial samples were collected from root canals by paper tip method and cultured, and colony forming units (CFU) values of each sample were calculated. Then the root canals were enlarged to the size of F3, after which dentin debris was collected from the F3 file. After dilution and culturing, the CFU value was calculated for each group. Two-way analysis of variance (ANOVA) was performed to test the interaction. The results revealed a significant antagonism (F = 3.394, P = 0.043). The bacterial CFU counts of group B and group C were significantly less than that of group A (P < 0.05), and there was no significant difference between group B and C (P > 0.05). Additionally, group 2A was better than group 1A (P < 0.05); there was no significant difference between group 1B and group 2B, group 1C and group 2C (P > 0.05). Comparison of the bacterial CFU counts in dentin debris after disinfection, the results revealed a significant antagonism (F = 7.224, P = 0.002), and group C had the least. The disinfection effect of Er:YAG laser or ultrasonic assisted computer-guided minimally invasive access is similar to conventionally invasive access, and Er:YAG laser is better than ultrasonic in removing bacteria from dentinal tubules and is easy to operate, which is more suitable for minimally invasive root canal treatment. [ABSTRACT FROM AUTHOR]

In recent years, extensive evidence has been published about usage of laser in oral lesions. The aim of the present study was to review the effectiveness of laser radiation in the treatment of pediatric oral soft tissue problems. The relevant keywords were searched in EBSCO, Medline (via Ovid), PubMed, Scopus, and Web of Science (WOS) databases. Then, eligible case series and controlled clinical trial studies, which published up to the end of 2018, were extracted and scrutinized. In this study, the age range of ≤ 21 years or the average age of ≤ 21 years was considered as the pediatric group. After limiting the search results, removing duplicate titles and eligibility evaluation, 17 papers were enrolled to the study (seven controlled clinical trials and ten case series). Er:YAG (2940 nm), CO2 (10,600 nm), Er,Cr:YSGG (2780 nm), and diode (650, 660, and 975 nm) lasers indicated successful clinical results on mucocele excision, frenectomy, gingival incision and re-contouring, and treatment of vascular malformations. In addition, 660-nm diode laser radiation was an effective adjuvant treatment for halitosis and gingivitis induced by multi-bracket appliances. Reduction or absence of pain and bleeding, suitable homeostasis, reduction of operation time, less analgesic consumption, and antibacterial effect were among the advantages of the laser radiation in the studies. Laser as a main or adjuvant tool can have an effective role in surgical and non-surgical treatments of pediatric oral soft tissue problems. Conducting further randomized controlled trial studies on different soft tissue lesions can contribute to drawing better conclusions. [ABSTRACT FROM AUTHOR]

Cervical cancer is one of the most common malignant tumors among female gynecological diseases. This paper aims to explore the feasibility of utilizing serum Fourier Transform Infrared (FTIR) spectroscopy, combined with machine learning and deep learning algorithms, to efficiently differentiate between healthy individuals, hysteromyoma patients, and cervical cancer patients. In this study, serum samples from 30 groups of hysteromyoma, 36 groups of cervical cancer, and 30 healthy groups were collected and FTIR spectra of each group were recorded. In addition, the raw datasets were averaged according to the number of scans to obtain an average dataset, and the raw datasets were spectrally enhanced to obtain an augmentation dataset, resulting in a total of three sets of data with sizes of 258, 96, and 1806, respectively. Then, the hyperparameters in the four kernel functions of the Support Vector Machine (SVM) model were optimized by grid search and leave-one-out (LOO) cross-validation. The resulting SVM models achieved recognition accuracies ranging from 85.0% to 100.0% on the test set. Furthermore, a one-dimensional convolutional neural network (1D-CNN) demonstrated a recognition accuracy of 75.0% to 90.0% on the test set. It can be concluded that the use of serum FTIR spectroscopy combined with the SVM algorithm for the diagnosis of cervical cancer has important medical significance. [ABSTRACT FROM AUTHOR]

Owing to the inadequate response to and limitations of the approved medications for androgenetic alopecia, novel therapies are warranted to enhance outcomes. The objective of this paper is to ascertain the effectiveness of fractional carbon dioxide laser followed by platelet-rich plasma application on hair regrowth and to compare the two laser settings. Seven participants were enrolled in this half-head pilot study based on different laser pulse energy and density values (12 mJ, 800 spots/cm2 and 22 mJ, 400 spots/cm2). Ten treatment sessions were performed every 2 weeks with 12-week follow-up. The evaluation methods were based on hair density from standardized phototrichograms, global photographic assessment, and patient satisfaction. Significantly increased total and terminal hair densities were observed during treatment in both groups as compared with baselines. The mean total hair density has weekly increased significantly with high pulse energy (1.42 hair/cm2) as compared to low pulse energy (1.04 hair/cm2) throughout the study period (p = 0.023; 4.89 hair/cm2). Global photographs and patient satisfaction scores demonstrated improvement, but only the latter showed statistical significance (p = 0.029). The average pain intensity scores were not different between the groups (p = 0.760) all over the procedure. The adverse events were minor and well tolerated. This synergistic treatment remarkably leads to hair restoration and high patient satisfaction. The parameters of 22-mJ beam energy with 400 spots/cm2 density are appropriate and superior to 12-mJ beam energy with 800 spots/cm2. Albeit higher energy, no more pain is indicated in the high pulse energy group. Trial registration number (TRN): TCTR20180619004, Thai Clinical Trials Registry (TCTR) since 2018-05-15 13:39:48 [ABSTRACT FROM AUTHOR]

The primary goal of this systematic review article was to provide an outline of the use of diabetic autologous adipose-derived mesenchymal stem cells (DAAD-MSCs) in the treatment of wounds and ulcers in animal models and patients with diabetes mellitus (DM). The secondary goal was to present the outcomes of pretreatment of diabetic adipose-derived mesenchymal stem cells (DAD-MSCs) with probable different agents in the treatment of diabetic foot ulcers (DFUs) and wounds. In view of possible clinical applications of AD-MSC-mediated cell therapy for DFUs, it is essential to evaluate the influence of DM on AD-MSC functions. Nevertheless, there are conflicting results about the effects of DAAD-MSCs on accelerating wound healing in animals and DM patients. Multistep research of the MEDLINE, PubMed, Embase, Clinicaltrials.gov, Scopus database, and Cochrane databases was conducted for abstracts and full-text scientific papers published between 2000 and 2020. Finally, 5 articles confirmed that the usage of allogeneic or autologous AD-MSCs had encouraging outcomes on diabetic wound healing. One study reported that DM changes AD-MSC function and therapeutic potential, and one article recommended that the pretreatment of diabetic allogeneic adipose-derived mesenchymal stem cells (DAlD-MSCs) was more effective in accelerating diabetic wound healing. Recently, much work has concentrated on evolving innovative healing tactics for hastening the repair of DFUs. While DM alters the intrinsic properties of AD-MSCs and impairs their function, one animal study showed that the pretreatment of DAlD-MSCs in vitro significantly increased the function of DAlD-MSCs compared with DAlD-MSCs without any treatment. Preconditioning diabetic AD-MSCs with pretreatment agents like photobiomodulation (PBM) significantly hastened healing in delayed-healing wounds. It is suggested that further animal and human studies be conducted in order to provide more documentation. Hopefully, these outcomes will help the use of DAAD-MSCs plus PBM as a routine treatment protocol for healing severe DFUs in DM patients. [ABSTRACT FROM AUTHOR]

Breast tumors are among the most common types of tumors that can affect both genders. It may spread to the whole breast without any symptoms. Therefore, the early detection and accurate diagnosis of breast tumors are significantly important. Current approaches for breast cancer screening such as positron emission tomography (PET) and magnetic resonance imaging (MRI) have some limitations of being time and money-consuming. In addition, mammography screening is not recommended for women under forty. Consequently, optical techniques have been introduced as safe and functional alternatives. Diffuse optical imaging is a non-invasive imaging technique that utilizes near-infrared light to examine biological tissues based on measuring the optical transmission and/or reflection at various locations on the tissue surface. In this paper, we propose a modified arrangement between the laser source and the detectors for distinguishing tumors from normal breast tissue. A three-dimensional model of the normal human breast with three types of tumors is developed using a COMSOL simulation software based on the finite element solution of Helmholtz equation to estimate optical fluence distribution. The breast model consists of four layers: skin, fat, glandular, and muscle, where the tumor is included in the glandular layer. Different wavelengths were used to determine the most proper wavelength for the discrimination between the normal tissue and tumor. The obtained results were verified using the receiver operating characteristic (ROC) method. The resultant fluence images show different features between normal breast and breast with tumor especially using 600-nm incident laser as demonstrated by the obtained ROC curves. [ABSTRACT FROM AUTHOR]

Refractive errors are the most common causes of vision impairment worldwide and laser refractive surgery is one of the most frequently performed ocular surgeries. Clinical studies have reported that approximately 10.5% of patients need an additional procedure after the surgery. The major complications of laser surgery are over/under correction and dry eye. An increase in temperature may be a cause for these complications. The purpose of this study was to estimate the increase in temperature during laser refractive surgery and its relationship with the complications observed for different surgical techniques. In this paper, a finite element model was applied to investigate the temperature distribution of the cornea when subjected to ArF excimer laser at a single spot using various beam delivery systems (broad beam, scanning slit, and flying spot). The Pennes bio-heat equation was used to predict the temperature values at different laser pulse energies and frequencies. The maximum temperature increase by ArF laser ( 500 Hz frequency and 0.5 J pulse energy) at a single spot was 33. 94 ∘ C , 15. 86 ∘ C , 12. 48 ∘ C for 6 diopter correction ( 65.4 μ m of ablation of corneal stroma) using broad beam, scanning slit, and flying spot beam delivery approaches respectively. The peak temperature due to a single pulse was estimated to be 234. 14 ∘ C . Although the peak temperature (sufficient energy to break intermolecular bonds) exists for a very short time ( 10 - 30 ns ) compared to the thermal relaxation time ( 2000 - 10 , 000 μ s ), there is some thermal energy exchange between corneal tissues during a laser refractive surgery. Heating may cause collagen denaturation, collagen shrinkage, and more evaporation and hence proposed to be a risk factor for over/under correction and dry eye. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effect of red laser (660 nm) photobiomodulation (PBM) with different energies on tumor necrosis factor-alpha(TNF-α) expression for random skin flap viability in rats. Twenty-four Wistar rats were divided into three groups: sham group (SG), PBM laser group with an energy dose of 0.29 J (0.29G), and PBM laser group with an energy dose of 7.30 J (7.30G). A cranially based dorsal skin flap measuring 10 × 4 cm was raised and a plastic barrier was placed between the flap and its bed. PBM was applied in 3 timepoints: in the immediate postoperative period, in the 1st and in the 2nd postoperative days; the animals were euthanized on the 7th postoperative day. The assessments included: TNF-α expression of 3 different flap areas (proximal, medial and distal), by immunohistochemistry; percentage of skin flap necrosis area, by the paper template method. The statistical analysis was performed through the Kruskal-Wallis and Mann-Whitney tests, the level of significance adopted was 5% (p < 0.05). TNF-α expression was significantly lower for 7.30G in the proximal area, reduced for SG in the medial point, and larger for 7.30G in the distal area. The percentage of flap necrosis area was significantly reduced for 7.30G. Higher energy doses are more efficacious than lower energy doses for modulating TNF-α expression. PBM with an energy dose of 7.30 J was effective in reducing the expression of TNF-α and increase skin flap viability. [ABSTRACT FROM AUTHOR]

Glioma is the most common primary central nervous system tumor; many methods are currently being used to research and treat glioma. In recent years, fluorescent-guided resection (FGR) and photodynamic therapy (PDT) have become hot spots in the treatment of glioma. Based on the existing literatures regarding the FGR enhancing resection rate and regarding efficacy of PDT for the treatment of glioma, this paper made a systematic review of FGR for gross total resection of patients and the PDT for the survival of patients with glioma. Meta-analysis of eligible studies was performed to derive precise estimation of PDT on the prognosis of patients with glioma by searching all related literatures in PubMed, EMBASE, Cochrane, and Web of Science databases, and further to evaluate (GTR) under FGR and the efficacy of PDT therapy, including 1-year and 2-year survival rates, overall survival (OS), and progression-free survival (PFS). According to the inclusion and exclusion criteria, a total of 1294 patients with glioma were included in the final analysis of 31 articles, among which a 73.00% (95% CI, 68.00 ~ 79.00%, P < 0.01) rate of GTR in 27 groups included in 23 articles was reported for those receiving FGR. The OS was 17.78 months (95% CI, 8.89 ~ 26.67, P < 0.01) in 5 articles on PDT-treated patients with glioma, and the mean difference of OS was 6.18 (95% CI, 3.3 ~ 9.06, P < 0.01) between PDT treatment and conventional glioma surgery, showing a statistically significant difference (P < 0.01). The PFS was 10.82 months (95% CI, 7.04 ~ 14.61, P < 0.01) in 5 articles on PDT-treated patients with glioma. A 1-year survival rate of 59.00% (95% CI, 38.00 ~ 77.00%, P < 0.01) in 10 groups included in 8 articles and 2-year survival rate of 25.00% (95% CI, 15.00 ~ 36.00%, P < 0.01) in 7 groups included in 6 articles were reported for those with PDT. FGR and PDT are feasible for treatment of patients with glioma, because FGR can effectively increase the resection rate, at the same time, PDT can prolong the survival time. However, due to the limitation of small sample size in the existing studies, larger samples and randomized controlled clinical trials are needed to analyze the resection under FGR and efficacy of PDT in patients with glioma. [ABSTRACT FROM AUTHOR]

Various clinical trials have explored whether the pulsed dye laser (PDL) method is safe to treat scars, especially surgical scars. However, comprehensive evidence confirming the exact outcomes of PDL for treating surgical scars is lacking. The efficacy and safety of PDL in the treatment of surgical scars were determined through a review of several studies. The PubMed, Embase, Cochrane Library, and Web of Science databases were searched, and the main clinical outcomes were Vancouver Scar Scale (VSS) scores in terms of pigmentation, vascularity, pliability, and height. Review Manager 5.4 software was used for statistical analyses of the data; we chose a standardized mean difference (SMZ) to present the results with 95% confidence interval (CI). Overall, seven randomized controlled trials were used for this meta-analysis, all of these papers used 585 nm or 595 nm PDL with 7 mm or 10 mm spot size and a fluence of 3.5 to 10 J/cm2 for treating surgical scars; besides, the pulse duration ranged from 450 μs to 10 ms. We found that PDL significantly resulted in decreased VSS scores (P = 0.02) in four aspects: pigmentation (P = 0.0002), vascularity (P < 0.00001), pliability (P = 0.0002), and height (P = 0.0002). Moreover, scar improvement was similar when using 585 nm and 595 nm PDL in terms of pigmentation (P = 0.76), vascularity (P = 0.34), pliability (P = 0.64), and height (P = 0.57). Furthermore, our review indicated that PDL has no obvious adverse effects for most people, except transitory erythema and purpura. The meta-analysis showed that both 585 nm and 595 nm PDL therapy can effectively reduce the VSS score, suggesting that PDL can be a safe and effective method for the treatment of surgical scars. [ABSTRACT FROM AUTHOR]

This paper is to explore the effectiveness of a new modified transnasal endoscopic marsupialization through Nd:YAG (neodymium: yttrium–aluminum-garnet) laser in treating nasolabial cysts in office. A prospective study was undertaken. Patients who suffered from nasolabial cysts from April 2016 to May 2017 at our hospital were involved. They were all treated with Nd:YAG laser transnasal endoscopic marsupialization. All patients were treated in the outpatient treatment room under local anesthesia. The patients ranged in age from 27 to 82 years, with an average age of 45 years. We made the diagnosis by the anatomical site, radiological imagings, and histopathology of the cyst. A total of 12 consecutive patients (men, n = 2; women, n = 10) with nasolabial cysts were involved in this study. Of the 12 patients, 6 were on the left and 8 were on the right side, and 2 had bilateral nasolabial cysts. All patients returned to clinic at 1, 6, and 36 months after treatment. At the follow-up time, none of the patients has mucus accumulation in the sinus or cyst recurrence, except for one patient who received treatment twice. No complications and recurrence during follow-up. In this study, we find that transnasal endoscopic marsupialization through Nd:YAG laser in treating nasolabial cysts is relatively effective, especially for patients who do not want to be hospitalized or treated under general anesthesia. [ABSTRACT FROM AUTHOR]

Hyposalivation is a condition represented by a reduced salivary flow and may include symptoms such as mouth dryness (xerostomia), loss of taste, pain, dysphagia, and dysphonia, all of which greatly affect an individual's quality of life. The aim of the present study was to systematically review the effects of low-level light therapy irradiation (photobiomodulation) on salivary gland function in patients with hyposalivation. The main question of the systematic review was: "Does low-level light irradiation therapy of the salivary glands affect salivary flow rate or indicators of salivary function (ion and protein concentrations) in patients with xerostomia or hyposalivation?" The question was based on the PICO (participant, intervention, control, outcome) principle and followed the PRISMA guidelines. Databases were explored and papers published between the years 1997 and 2020 were reviewed for the following Mesh-term keywords and their corresponding entry terms in different combinations: "Low-level light therapy," "Xerostomia," "Saliva," "Salivary glands," "Salivation." The initial sample consisted of 220 articles. Of those, 47 articles were used for full-text analysis and 18 were used for a systematic review, 14 were used in meta-analysis. According to their individual quality, most articles were classified as high quality of evidence according to the GRADE score. Meta-analysis of the evidence observed increase of unstimulated salivary flow 0.51 SMD compared to placebo (95% CI: 0.16–0.86), I2 = 50%, p = 0.005. The findings of our review revealed evidence of a beneficial effect of photobiomodulation therapy on salivary gland function. The therapy alleviates xerostomia and hyposalivation. However, these effects are reported short term only and did not induce lasting effects of photobiomodulation therapy on patients' quality of life. [ABSTRACT FROM AUTHOR]

Cancer continues to be the most dangerous disease around the world; it causes electrolyte imbalance as well as metabolic changes. There is a complicated relationship between electrolyte disorder and cancer. Cancer patients commonly pass with abnormalities in serum electrolyte levels such as hypokalemia, hyperkalemia, hyponatremia, and hypercalcemia. So, these electrolyte imbalances indicate the existence of paraneoplastic processes and help come to a more informed prognosis. Hypokalemia is defined as a serum potassium concentration below 3.5 mmol/L and it is the second common electrolyte imbalance seen in patients with malignant diseases. In this paper, the contribution of serum potassium concentration to tumor progression was studied by applying a promising and non-invasive technique called laser-induced breakdown spectroscopy (LIBS). It was found that there is a correlation between hypokalemia and the colorectal cancer problem. Also, significant serum potassium concentration differences were detected among two different stages of the same cancer and also between two groups of the same stage of a cancer held in common but one of them suffers from hypercalcemia. In addition, the optimum conditions of LIBS setup were arranged such that it will be suitable to work with serum samples on glass substrate. [ABSTRACT FROM AUTHOR]

Inferior alveolar nerve (IAN) damage is a common complication occurring after sagittal split osteotomy (SSO) and results in sensory disorders of the jaw region. In recent years, published experimental and clinical evidence suggests that low-level laser (LLL) radiation is effective in nerve recovery. Therefore, the aim of the present study was to review clinical trial studies investigating the effect of LLL radiation on improving the sensory defects of IAN after SSO. The keywords associated with SSO and LLL were searched in PubMed, Medline (via Ovid), Web of Science (WOS), Scopus, and Cochrane Library databases. Then, controlled clinical trial studies published before November 2017 regarding LLL radiation conducted on patients with IAN neuropathy due to SSO were investigated. The articles fulfilling the study criteria were further scrutinized and the necessary information was extracted from them. A total of seven papers were included in the study. The diode laser used had a wavelength range of 760-930 nm, radiation power of 20-200 mw, and radiation energy of 10.2-95 J (per point of radiation). In the mentioned studies, the patients underwent 3-20 sessions of laser irradiation and were monitored for an additional 0-23 months after completion of the laser intervention. The tests performed in the mentioned studies dealt with examining the perceptions of superficial touch and pressure, two-point discrimination, stimulus movement on skin, temperature, and pain. Furthermore, the patients' general awareness regarding sensory perception in the mandibular region was gauged. In six studies, laser irradiation caused relative improvement in the IAN sensory disorder for a subjective test as well as for one or more objective tests. In the reviewed clinical trial studies, LLL was generally found to be effective in improving the IAN sensory disturbance resulting from SSO, though there was no placebo effect. [ABSTRACT FROM AUTHOR]

Keywords: Public Health; Quantum Electronics; Nonlinear Optic; Hard Tissue; Ablation Efficacy EN Public Health Quantum Electronics Nonlinear Optic Hard Tissue Ablation Efficacy 1 1 1 12/09/22 20221202 NES 221202 This article was retracted by the Editors, as the paper was originally published by Mersini I Makropoulou and Eirini I Papagiakoumou (2004) Lasers and hard-tissue interactions. Public Health, Quantum Electronics, Nonlinear Optic, Ablation Efficacy, Hard Tissue. [Extracted from the article]

Early detection of cervical lesions, accurate diagnosis of cervical lesions, and timely and effective therapy can effectively avoid the occurrence of cervical cancer or improve the survival rate of patients. In this paper, the spectra of tissue sections of cervical inflammation (n = 60), CIN (cervical intraepithelial neoplasia) I (n = 30), CIN II (n = 30), CIN III (n = 30), cervical squamous cell carcinoma (n = 30), and cervical adenocarcinoma (n = 30) were collected by a confocal Raman micro-spectrometer (LabRAM HR Evolution, Horiba France SAS, Villeneuve d'Ascq, France). The Raman spectra of six kinds of cervical tissues were analyzed, the dominant Raman peaks of different kinds of tissues were summarized, and the differences in chemical composition between the six tissue samples were compared. An independent sample t test (p ≤ 0.05) was used to analyze the difference of average relative intensity of Raman spectra of six types of cervical tissues. The difference of relative intensity of Raman spectra of six kinds of tissues can reflect the difference of biochemical components in six kinds of tissues and the characteristic of biochemical components in different kinds of tissues. The classification models of cervical inflammation, CIN I, CIN II, CIN III, cervical squamous cell carcinoma, and cervical adenocarcinoma were established by using a support vector machine (SVM) algorithm. Six types of cervical tissues were classified and identified with an overall diagnostic accuracy of 85.7%. This study laid a foundation for the application of Raman spectroscopy in the clinical diagnosis of cervical precancerous lesions and cervical cancer. [ABSTRACT FROM AUTHOR]

Uniform dosimetry is a prerequisite for reproducible laser applications in research and practice. The light–tissue interaction is dependent on the absorbed energy (J) per unit of time (τ) in the case of pulsed lasers, and on the absorbed power (W) per unit of volume (e.g. mm3) in the case of continuous-wave (cw) lasers, and thus directly dependent on the energy distribution within the laser beam. Consequently, precise knowledge of the spatial beam profile, and of the pulse duration and treatment time, is indispensable. The objective of this paper was a theoretical study of the impact of different mode profiles on energy distribution in the beam. Also examined was the question of the influence of changes in the laser parameters on the mode structure. Three erbium:YAG lasers (λ=2.94 μm) were used for this purpose. The transversal mode structure of the lasers was observed by irradiating thermal paper and verified by means of calculations. The effect induced in the mode profile by changing the pulse energy and pulse repetition rate was investigated. The results of the tests show that changes in the laser parameters result in jumps in the transversal modes and associated energy distributions in the beam. The experiments confirm that simply changing the transversal modes has a substantial effect on the threshold energy required for the ablation of dental enamel (50 mJ with TEM00, 22.6 mJ with TEM31). In practice, inhomogeneity makes it impossible to determine the irradiated area in order to calculate the energy or power density. In addition, the energy distribution in the beam changes as a result of variation of the laser output energy and the pulse repetition rate. Consequently, simply measuring the beam diameter yields a totally incorrect result for the applied flux density when using a beam profile with a relatively high mode. [ABSTRACT FROM AUTHOR]

Laser-induced breakdown spectroscopy (LIBS) is an emerging analytical technique with numerous advantages such as rapidity, multi-elemental analysis, no specific sample preparation requirements, non-destructiveness, and versatility. It has been proven to be a robust elemental analysis tool attracting interest because of being applied to a wide range of materials including biomaterials. In this paper, we have performed spectroscopic studies on gallstones which are heterogeneous in nature using LIBS and wavelength dispersive X-ray fluorescence (WD-XRF) techniques. It has been observed that the presence and relative concentrations of trace elements in different kind of gallstones (cholesterol and pigment gallstones) can easily be determined using LIBS technique. From the experiments carried out on gallstones for trace elemental mapping and detection, it was found that LIBS is a robust tool for such biomedical applications. The stone samples studied in the present paper were classified using the Fourier transform infrared (FTIR) spectroscopy. WD-XRF spectroscopy has been applied for the qualitative and quantitative analysis of major and trace elements present in the gallstone which was compared with the LIBS data. The results obtained in the present paper show interesting prospects for LIBS and WD-XRF to study cholelithiasis better. [ABSTRACT FROM AUTHOR]