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Introduction: Pinhole intraocular lenses (IOLs) were developed to improve reading by compensating for loss of accommodative function. The IC-8® Apthera™ is a small-aperture presbyopia-correcting IOL that combines the proven principle of small-aperture optics with an aspheric monofocal lens to deliver a continuous range of vision for patients with cataracts from distance to near vision. Posterior capsule opacification is the most common sequela after cataract surgery. It is effectively treated by laser capsulotomy. However, if the laser beam is incorrectly focused, the IOL can be permanently damaged (pits/shots). Methods: In this experimental study, yttrium–aluminum-garnet (YAG) pits were purposefully created. Defects were analyzed and compared between the periphery of the ring in the clear area of the hydrophobic acrylic lens and at the carbon black (CB)-polyvinylidene fluoride (PVDF) filtering component (FilterRing™) of the pinhole lens. All defects were made using identical settings/energy levels (2.6 mJ). The damage induced to the IC-8® Apthera™ IOL was examined by low-magnification images, light microscopy, scanning electron microscopy, and micro-computed tomography (micro-CT). Results: YAG defects in the carbon black filter ring were much more severe than those in the clear zone due to the high absorption of the carbon black. Massive defects and destruction of the lens with tearing out of fragments and particles were observed. The missing volume calculated from the micro-CT reconstruction was 0.266 mm3, which is 1.6% of the entire IOL volume, or more than 1000 times the volume damaged in the largest shot in the periphery. Conclusion: Based on the results, we highly recommend using the lowest possible energy levels, posterior offset setting, and circular pattern for maximum safety when performing laser capsulotomy with pinhole implants. Care should be taken to avoid creating irreversible iatrogenic defects that may affect overall quality. The safest area for performing capsulotomy seems to be the periphery of the ring segment. Video available for this article. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Objective Methods Results Conclusion Melasma is a therapeutically challenging hyperpigmented skin condition. Currently, there is a lack of in vivo observation regarding changes in melanin and dendritic melanocytes after laser treatment.To investigate alterations in melanin and melanocytes in melasma before and after laser treatment using optical coherence tomography (OCT).Eight female melasma patients were enrolled in Taiwan. Based on the baseline OCT scans, the patients were categorized into either epidermal‐type or mixed‐type melasma and were assigned different treatment protocols accordingly. Sequential OCT images were collected from melasma lesions and normal skin at baseline, Week 4 and Week 8.After 8 weeks of laser treatment, the mean Melasma Area Severity Index (MASI) score improved from 10.92 to 6.30. Results from OCT showed no significant changes in the normalized density, area, or intensity of melanin in both lesional and normal skin. At baseline, the mean length of dendritic melanocytes in the affected skin was 15% longer than those in normal skin; at Week 8, the mean length of lesional dendritic melanocytes became the same as those in normal skin. Additionally, the mean width of dendritic melanocytes decreased from being 4% wider to only 2% wider than those in normal skin.After 8 weeks of treatment, an improvement of MASI score was noted, mainly attributable to a reduction in lesional area. OCT showed no notable change regarding melanin, but a decrease in length and width of dendritic melanocytes was noted in the lesional skin of melasma patients. [ABSTRACT FROM AUTHOR]

Background: Solar lentigo, a common epidermal hyperpigmented lesion found in sun‐exposed areas, results from the proliferation of melanocytes and the accumulation of melanin. Although various treatments for solar lentigo have been explored, they often lead to complications, including prolonged erythema and post‐inflammatory hyperpigmentation (PIH), posing significant concerns. Objectives and methods: This study evaluated the safety and efficacy of the Vasculature Salvage Laser Surgery (VSLS) system. We treated six Korean patients, each with solar lentigo, in a single session using the 532‐nm nanosecond neodymium‐doped yttrium aluminum garnet (Nd:YAG) VSLS system, with follow‐up periods ranging from 3 to 10 weeks. Results: The treatment led to the complete removal of pigmented lesions in all patients without resulting in PIH, even in cases where previous laser treatments had failed. The only side effect observed was mild erythema, which resolved over the long term in most instances. Conclusions: The VSLS system emerges as a safe and effective treatment for pigmented lesions, including refractory solar lentigines. Nonetheless, additional studies are required to verify its long‐term efficacy. [ABSTRACT FROM AUTHOR]

Angiolymphoid hyperplasia with eosinophilia (ALHE) is a benign vascular proliferative condition, typically presenting as subcutaneous nodules in the head and neck region of middle‐aged women. Kimura disease (KD) is a benign condition that presents with subcutaneous nodules in a similar distribution with lymphadenopathy and eosinophilia, typically in Asian adult males. These diseases are often discussed together, including whether they exist on a spectrum or if they represent separate disease entities. Both are very rare in the pediatric population; in this report we highlight the case of a 10‐year‐old Caucasian male presenting with ALHE and KD. [ABSTRACT FROM AUTHOR]

The effects of laser beam welding (LBW) process parameters on the characteristics of Nd:YAG laser butt welding 1.5 mm thick 2205 duplex stainless steel. Specifically, the study focuses on the depth of penetration, bead width, ultimate tensile strength (UTS) and elongation. To achieve this, a parametric study is conducted using a central composite design (CCD) with response surface methodology (RSM) to establish mathematical regression equations that identify the key process parameters and their effects on the responses. The investigations showed that the size of the meltpool at the fusion zone (FZ) increases as the laser power increases. This leads to the formation of wider and deeper weld beads, ultimately leading to stronger and more flexible joints. Similarly, pulse width and scanning speed have a significant impact on the weld bead geometry, UTS, and elongation. It is observed that the FZ is free of any visible cracks, voids, or porosity. The LBW process parameters have been optimized to reduce operating costs by lowering the line energy, without compromising the welding quality. The optimal UTS value for the welded joint is around 865 MPa, which is almost equivalent to 99% of the UTS of the 2205 duplex stainless steel base material (BM). To obtain high-quality welded joints, it is recommended to use a laser power ranging from 423 to 425 W, scanning speed of 5.3 mm/s and pulse width of 5.4 ms. [ABSTRACT FROM AUTHOR]

Nail psoriasis is a chronic, inflammatory condition which is difficult to treat, linked with greater psoriasis severity, and may be associated with anxiety and significant functional impairment of the quality of life. The 1064 nm Nd: YAG laser was reported to yield satisfactory results in the treatment of nail psoriasis. The aim of the study was to assess the clinical and ultrasonographic efficacy of long-pulsed 1064 nm Nd: YAG laser in the treatment of fingernail psoriasis and compare its effect to control fingernails. This intra-patient randomized controlled trial analyzed 86 fingernails collected from 13 patients suffering from cutaneous and nail psoriasis. The nails were randomized into two groups. Group A was treated with Nd: YAG laser once monthly for three sessions while group B served as control. Assessment took place at baseline, 1 and 3 months after the last treatment session. For scoring, the 32-points target NAPSI scoring systems was used. Additionally, two blinded dermatologists' score of improvement, patients' pain assessment by visual analogue score and ultrasonographic assessment were all performed. At the end of follow up, the medians of tNAPSI score, plate definition, matrix thickness, bed thickness and bed vascularity decreased significantly in the Nd: YAG laser treated group in comparison to baseline (p = 0.001, 0.006, 0.039, < 0.001 and 0.010, respectively). While, there was a non-significant reduction in median tNAPSI score in the control group at last follow up, however, ultrasonography recorded a significant reduction in the medians of plate definition, bed thickness and vascularity (p = 0.002, 0.011 and 0.033, respectively) from the baseline. Comparison of the Nd: YAG laser and the control groups showed no significant difference from baseline regarding the medians of tNAPSI, tNAPSI percentile improvement, pits count, blinded evaluation of photographs and ultrasonographic assessments. In conclusion, Nd: YAG laser showed clinical and ultrasonographic improvement in fingernail psoriasis. Ultrasonography is a useful noninvasive tool in diagnosing and monitoring the clinical and even the subclinical changes in nail psoriasis. Nail psoriasis although difficult to treat, may show spontaneous improvement. [ABSTRACT FROM AUTHOR]

This research work investigates surface morphology, plasma plume intensity and the hardness of palladium thin film deposited on silicon substrates under the action of laser light. For this purpose, a pulsed Nd:YAG laser (1064 nm, 10 mJ, 12 ns) was used to irradiate the specimen with repetitive laser pulses. The experiment was repeated under the illumination with UV light. The surface morphology of the specimens was examined through an Optical and Field-Emission Scanning Electron Microscopy showing thermal conduction, exfoliation, crater formation, re-deposition of the material, ripples formation, debris, heat-affected zone, holes formation and the formation of nanoparticles. The diameter and the depth of the crater formed on non-UV illuminated Pd thin film were greater than the crater formed on UV illuminated Pd thin film, because of its higher absorption. The photographs of the plasma plume were captured with a computer-controlled image capture system and examined by image processing software. The intensity of UV-illuminated Pd thin film was higher than non-UV illuminated Pd thin film because UV illumination induces defects in the specimen that have additional electronic states. These defects cause higher absorption and more ionization of the target material and emerge a more luminous plasma plume. A nanoindentation test was applied on the material surface to investigate the mechanical properties such as hardness and elastic modulus of the target specimen. The hardness and elastic modulus of the material were increased by cumulative laser shots. [ABSTRACT FROM AUTHOR]

The aim of the study was to measure the degree of dentine surface roughness caused by five distinct lasers used to treat dentine hypersensitivity, as well as to evaluate the subsequent bacterial colonization on these irradiated surfaces. Sixty human maxillary premolar teeth without caries or restoration which were extracted for periodontal reasons were used in this study. Five different types of lasers were applied to the root dentin surface. Tested samples were divided into six groups of 10 samples each; control, diode (810 nm), diode (980 nm), Nd: YAG, Er: YAG, and Er, Cr: YSGG laser groups. The arithmetic mean of the surface roughness values (Ra) and the average roughness over a measurement area (Sa) were measured pre- and post-application using any of the laser types. Swab samples were then collected from the dentin surface. Following a 24-hour incubation period at 37 °C, the colony forming units were counted using a stereoscope. The results demonstrated a statistically significant difference in the surface roughness values pre- and post-application (Ra and Sa, respectively) in the Er, Cr: YSGG laser group (p = 0.037,p = 0.007). No significant difference was observed in the other groups (p > 0.05). There was no statistically significant difference in the number of bacterial colonies observed between the test and control groups. Diode and Nd: YAG lasers showed either a decrease or no change in surface roughness; however, the hard tissue lasers (Er: YAG, Er, Cr: YSGG) showed an increase. The Er: YAG and Nd: YAG laser groups exhibited decreased bacterial adhesion compared to the other groups. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate alterations in the concentrations of matrix metalloproteinase-9 (MMP-9) and interleukin-8 (IL-8) within gingival crevicular fluid (GCF) extracted from the intrabony periodontal defect site before and after minimally invasive regenerative surgery, with or without supplemental laser application. The surgical procedure was performed using the modified minimally invasive surgical technique (M-MIST). Methods: Thirty-eight patients, each presenting with a single vertical defect, were randomly assigned to either the test (M-MIST + Er:YAG + Nd:YAG) or the control group (M-MIST). IL-8 and MMP-9 levels (primary outcomes of the study) were assessed prior to therapy, after 2 and 4 weeks, and 6 months following the surgical procedure by means of dedicated ELISA kits. Results: Both procedures were clinically effective as evidenced by probing depth (PD) reduction and clinical attachment level (CAL) gain at the 6-month follow-up. No statistical differences were observed in the levels of MMP-9 and IL-8 between the groups at any time point assessed. The changes in the level of MMP-9 and IL-8 over time were not statistically significant in any group. IL-8 was positively correlated with MMP-9 in the control group throughout the study and in the test group 2 weeks and 6 months post-op. Conclusions: Within the limitations of this study, the additional application of Er:YAG + Nd:YAG lasers alongside the M-MIST procedure did not enhance the clinical and biochemical treatment outcomes compared to M-MIST alone. [ABSTRACT FROM AUTHOR]

Background and Aims: Strong bond between the ceramic brackets and ceramic veneers has an important role in cosmetic treatment. The purpose of this study was to investigate the effect of aging on the shear bond strength (SBS) of ceramic brackets bonded to zirconia after surface preparation by Neodymium-doped Yttrium Aluminum Garnet (Nd: YAG) laser or sandblasting with alumina. Materials and Methods: This experimental study was conducted on 24 zirconia blocks and these blocks were randomly divided into two groups for surface preparation and each was sub-divided into three time intervals. Surface preparation was done by sandblasting with alumina: in SG1 (Immediately after sandblasting), SG2 (2 weeks after sandblasting), and SG3 (3 months after sandblasting) groups. For the Nd: YAG laser (1/5W, 20Hz, 10s) with non-contact mode: in LG4 (Immediately after laser), LG5 (2 weeks after laser), and LG6 (3 months after laser) groups. The ceramic brackets were bonded to the zirconia blocks. The SBS and adhesive remnant index (ARI) were evaluated and compared among test groups. Dara were analyzed using Mann Whitney test. Results: There was no significant difference between the SBS of SG1 and LG4 (P=0.430), SG2 and LG5 (P=0.382) and SG3 and LG6 (P=0.326) groups. LG4 group showed the highest shear bond strength. After aging (2 weeks and 3 months), the laser groups showed higher SBS. There was no significant difference in the ARI between SG1 and LG4 (P=0.220), SG2 and LG5 (P=0.154), SG3 and LG6 (P=0.527) groups. Conclusion: No significant difference was observed between the Nd: YAG laser and sandblasted groups in terms of SBS and ARI over time. Therefore, Nd: YAG laser could be used as a surface treamnet method in Zirconia crowns for bonding to ceramic brackets. [ABSTRACT FROM AUTHOR]

AIM: To explore the value of the corneal/refractive analyzer OPD-Scan III in assessing visual quality after Nd:YAG laser surgery in patients with posterior capsular opacification.METHODS: A total of 98 patients(98 eyes)with posterior capsular opacification who underwent Nd:YAG laser posterior capsulotomy in our hospital from May 2021 to April 2023 were retrospectively selected as the research subjects, and higher-order aberration parameters(coma, spherical aberration and trefoil aberration)and visual quality parameters [Strehl ratio(SR)and 4 mm area ratio(AR)in the human eye modulation transfer function(MTF)curve] were obtained using the corneal/refractive analyzer OPD-Scan III. The patient's visual acuity, higher-order aberration parameters and visual quality before surgery, and at 1 wk and 3 mo after surgery were compared.RESULTS: There were statistically significant differences in uncorrected distance visual acuity(UDVA), uncorrected intermediate visual acuity(UIVA)and uncorrected near visual acuity(UNVA), coma, spherical aberration, trefoil aberration, SR and AR before and after surgery(all P0.05). Furthermore, the spherical aberration, trefoil aberration were negatively correlated with SR(rs=-0.427, P=0.009; rs=-0.436, P=0.010), and the trefoil aberration was negatively correlated with AR(rs=-0.406, P=0.015).CONCLUSION: The visual acuity of patients with posterior capsular opacification improved after Nd:YAG laser surgery, and the corneal/refractive analyzer OPD-Scan III system has a high clinical value in reflecting patient's visual quality.

Adhesive bonding is widely used in aeronautical carbon fiber-reinforced polymer (CFRP)/titanium (Ti) alloy hybrid structures to satisfy the demands of high-strength and lightweight. The physicochemical properties of adherend surfaces significantly impact the bonding performance. In this study, laser-induced surface reconstruction (LISR) was designed for the reliable joining of Ti alloy and CFRP. A three-level-three-factor central composite design (CCD) approach-based response surface methodology (RSM) analysis was applied to statistically specify parameter optimization of the laser energy output. Surface morphology and wettability of CFRP ablated were studied. Chemical compositions were determined by X-ray photoelectron spectroscopy (XPS). Tensile-shear tests were performed, and fractured surfaces were analyzed. The tensile shear strength with LISR process has been improved by 19.1%, in comparison with that of mechanical grinding treatment. The cross-like texture based on designed geometric configuration was fabricated without damaging the underlying fibers, thus increasing the surface roughness and contact area at interface. The wettability transition mechanism was investigated, demonstrating that the hydrophilicity of reconstructed surfaces primarily attributes to the more polar groups (C–O, CO, etc.) on CF surfaces. This study provides a reliable surface treatment method for fabricating high-performance composite structures by adhesive bonding.

Background: Transscleral cyclophotocoagulation (TSCPC) is most commonly used in patients with neovascular glaucoma (NVG) associated with proliferative diabetic retinopathy (PDR) in whom maximal hypotensive medications have failed to reduce intraocular pressure (IOP) to the desired level, and glaucoma surgery cannot be carried out. Options for CPC can be performed using a neodymium:yttrium-aluminum-garnet (Nd:YAG) laser or diode laser. Purpose: To compare the efficacy of TSCPC performed with the 1,064-nm Nd:YAG laser versus 810-nm diode laser in patients with painful NVG associated with PDR over a 12-month follow-up period. Material and Methods: A prospective cohort study was carried out on 58 type 2 diabetics (58 eyes) who received a 1,064-nm Nd:YAG laser TSCPC or 810-nm diode laser TSCPC for painful NVG associated with PDR, with regular follow-up visits over 12 months and had no previous history of treatment with CPC. IOP between 6 and 21 mmHg (or a reduction in IOP of ≥ 30% from baseline IOP) and no ocular pain at 12 months was the primary outcome measure. Results: The success rate at 12 months was 75% and 77% for eyes that received Nd:YAG laser TSCPC and diode laser TSCPC, respectively (p = 0.86). In the Nd:YAG laser TSCPC and diode laser TSCPC groups, the IOP reduced by 46% and 45%, respectively (p = 0.34) from baseline values of 38.0 mmHg and 36.0 mmHg, respectively (p = 0.96) at month 12 after TSCPC. At month 12 after CPC, the BCVA in patients with preserved pattern vision improved in both groups (p = 0.41). The rate of ocular complications was, however, higher in the diode laser TSCPC group (71% versus 33%, p = 0.004). Conclusion: Nd:YAG laser TSCPC resulted in a reduction in IOP to ≤ 21 mmHg at month 12 in 75%, and diode laser TSCPC, in 77% of patients with NVG associated with PDR. The number of sessions required for treatment success was 3.2 times larger for Nd:YAG laser CPC than for diode laser CPC. Both these types of CPC are safe and can be repeatedly used to improve treatment efficacy.

Nowadays, lasers are used in various medical fields. Ophthalmology was the first medical specialty to utilize lasers in patient treatment and still remains the leading medical field that uses laser energy for both therapeutic and diagnostic purposes. The neodymium: yttrium-aluminum-garnet (Nd: YAG) laser is one of the most common lasers used in ophthalmology. It is a solid-state laser with a wavelength of 1064 nm that works on the principle of photodisruption. Since its introduction in ophthalmology over 40 years ago, it has found various applications, mainly for procedures where cutting or disruption of ocular tissue is required. Compared to surgical alternatives, the use of Nd: YAG lasers on ocular tissue is minimally invasive. In this review, we focus on the two most common ophthalmic applications of Nd: YAG laser – laser peripheral iridotomy and posterior capsulotomy. The history of the techniques, current trends, potential complications, and the prognosis for future use is discussed. [ABSTRACT FROM AUTHOR]

The characteristics of an Nd:YAG multistage optical amplifier of a laser beam, the spatial parameters of which were corrected by thermal lenses formed in the active elements of each amplifier stage, were studied. Nd:YAG crystals transverse-pumped by laser diode units were used as the amplifier active elements. Removal of lens-compensators was shown to reduce the total optical losses of the amplifier and enhance its compactness. The optical losses of an optical amplifier with five amplification stages and correction of the amplified beam characteristics by thermally induced lenses of active elements were 16%; its linear dimensions, 13% less than similar indicators for a five-stage amplification system with four two-lens compensators between amplification stages. [ABSTRACT FROM AUTHOR]

Stainless steel is a notably beneficial product and is widely used in many applications. Controlling the quality of steel products by determining their trace elemental content is essential. The content of trace elements such as Cr in steel protects the alloy from corrosion and enhances its lifetime, especially in the case of steel embedded in concrete structures. This article presents a quantitative analysis of the trace element Cr in steel samples using advanced laser-induced breakdown spectroscopy (LIBS) with an Nd:YAG laser at wavelengths of 355 and 1064 nm. The LIBS emission intensity of Cr at a laser wavelength of 355 nm was improved compared to that at 1064 nm. Notably, the calibration curves exhibit a zero intercept using the LIBS technique at the third harmonic (355 nm) and fundamental (1064 nm) wavelengths generated by the Nd:YAG laser. The detection limits for Cr in steel were determined as 21 and 36 parts per million using the laser wavelengths of 355 and 1064 nm, respectively. This study demonstrated that the wavelength of 355 nm is significantly more suitable for the quantitative analysis of stainless steel than 1064 nm in laser-induced spectroscopy. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of Nd:YAG laser combined with Icon penetrating resin on dental fluorosis and the influence on aesthetics. Methods: 486 teeth were selected from 80 patients with dental fluorosis treated in our hospital from June 2018 to June 2023. The 80 patients were divided into two groups according to random number table method. The control group received Nd: YAG laser treatment, and the observation group received Nd:YAG laser treatment combined with Icon penetrant resin treatment. The col- or scale change, bleaching effect, lesion area ratio, enamel hardness of affected tooth were compared between the two groups at different time points, and tooth sensitivity and patient satisfaction were compared between the two groups during treatment. Results: Immediately after treatment and 12 weeks after treatment, and the observation group was lower compared with the control group (P<0.05). Immediately after treatment, the response rate 84.17% was significantly higher than the 76.42% in the control group (P<0.05), and 12 weeks after treatment, the efficacy rate 94.17% was higher than the 82.93% in the control group (P<0.05). The lesion area ratio decreased in the immediate and 12 weeks after treatment, and the observation group was lower compared with the control group (P<0.05). Lower enamel stiffness in the control group immediately at 12 weeks compared to the pretreatment and observation groups (P<0.05). The tooth sensitivity and satisfaction of the observation group were better than those of the control group (P<0.05). Conclusion: Nd:YAG laser combined with Icon penetrating resin can improve the curative effect of dental fluorosis, reduce the ratio of damaged area, sensitivity of dental fluorosis, improve aesthetic effect, and do not affect the hardness of dental enamel. It is a potential treatment method for dental fluorosis. [ABSTRACT FROM AUTHOR]

This systematic review assesses the evidence concerning laser treatments for nail psoriasis (NP), a prevalent condition among individuals with cutaneous psoriasis that notably affects their quality of life. Traditional treatments have limitations in terms of drug delivery and poor patient adherence, leading to interest in laser therapies for their targeted approach, extended treatment intervals, and the potential to enhance topical medication effectiveness. The MEDLINE, Embase, Web of Science, and Cochrane Library databases were searched. English‐language randomized and non‐randomized controlled trials with full‐text availability were included. Data on the laser type, treatment protocol, Nail Psoriasis Severity Index (NAPSI) outcomes, and adverse events were extracted, and nail bed and matrix features and patient satisfaction were assessed. The primary effect measure was a percentage reduction in NAPSI scores from baseline. Nineteen studies involving the pulse dye laser (PDL), long‐pulsed neodymium:yttrium aluminum garnet (Nd:YAG) laser and fractional carbon dioxide laser (FCL) were identified. Lasers, particularly those used in conjunction with topical agents, have shown favorable results. PDL effectively lowered NAPSI scores, and the Nd:YAG laser had comparable effectiveness but more discomfort. FCL also shows promise, particularly for topical drug delivery. PDL and Nd:YAG laser treatment were more effective at reducing nail bed features, whereas FCL was effective at reducing both nail bed and matrix features. Overall, lasers are promising treatment alternatives for NP, with similar NAPSI outcomes to topical therapies and intralesional injections. [ABSTRACT FROM AUTHOR]

Background: To evaluate the efficacy and safety of stromal vascular fraction (SVF), platelet rich plasma (PRP), and 1064‐nm Q‐switched Nd:YAG laser in reducing nanofat treated dark circles and wrinkles under the eyes. Method: This study was a single‐blinded randomized clinical trial conducted on patients with suborbital darkening under the eyes that randomly divided into control and case groups. In the control group, 15 patients were treated with one session of nanofat injection only, and five patients of each intervention groups received one session of nanofat+SVF injection, nanofat+PRP injection, and nanofat injection+Nd:YAG laser, respectively. Assessments methods were (1) evaluation of the degree of darkness and repair under the eyes by a blinded dermatologist based on clinical photographs, (2) investigating patient satisfaction, (3) using biometric variables for color, thickness, and density of the skin (only 3 months after the treatment), and (4) recording the possible adverse effects. Conclusion: In terms of the extent of reduction in the intensity of darkness under the eyes, the combined treatment of nanofat injection together with SVF, PRP, and Nd:YAG laser had a much greater therapeutic effect than nanofat injection alone. In all three groups of combined treatments, patients were 100% satisfied. In terms of biometric variables, amount of changes in colorimeter, complete and dermal thickness, complete and dermal density, between the different groups was statistically significant. The use of combined treatments including nanofat with SVF injection, PRP, and 1064 Q‐switched Nd:YAG laser may be more effective than nanofat alone, in reducing infraorbital dark circles and wrinkles. [ABSTRACT FROM AUTHOR]

The use of low-fluence picosecond (LFPS) 1064 nm neodymium-doped yttrium aluminum garnet (Nd:YAG) lasers, referred to as laser toning, is increasingly acknowledged as an effective treatment for pigmentation disorders in the Asian skin phenotype. This study aimed to conduct a comparative analysis on the effectiveness and safety of utilizing LFPS 1064 nm Nd:YAG lasers against picosecond 532 nm Nd:YAG lasers in treating pigmented lesions among Chinese patients. A retrospective photographic analysis and chart reviews were performed on 31 subjects exhibiting Fitzpatrick skin types III–VI who underwent LFPS 1064 nm Nd:YAG or picosecond 532 nm Nd:YAG treatments at a single tertiary center. Utilizing VISIA Complexion Analysis, comparative photographs were taken. Two independent physicians evaluated treatment efficacy using a visual analog scale (VAS) to assess the percentage of pigmentary clearance in standard photographs. Solar lentigines were the most prevalent pigmentary disorder, followed by post-inflammatory hyperpigmentation (PIH), nevus zygomaticus, melasma, freckles, and nevus of Ota. The clinical effectiveness of picosecond 532 nm and LFPS 1064 nm laser treatments proved comparable for lesions on the face, with mean VAS scores of 2.2 ± 1.1 and 1.8 ± 0.8, respectively. There were two cases of PIH in the picosecond 532 nm group, which resolved within one month. Overall, the LFPS 1064 nm laser demonstrates promise as a safe and efficient therapeutic modality for managing pigmented lesions in Chinese patients. [ABSTRACT FROM AUTHOR]

Laser, an acronym for Light Amplification by Stimulated Emission of Radiation, is a powerful tool with diverse applications in modern dentistry. It emits monochromatic, coherent light resulting from photon-induced chain reactions. Available dental lasers include diode, argon, Er,Cr:YSGG, Er:YAG, Nd:YAG, and CO2. The unique property of these lasers, allowing them to be effectively used on both soft and hard tissues based on the operational parameters, positions them as particularly suited for a wide range of dental procedures. Compared to traditional methods, lasers offer advantages such as improved hemostasis and quicker wound healing. Such benefits stress the shift towards laser technology in dental treatment. In the realm of dental prosthodontics, which focuses on esthetics, functionality, and the physiological aspects of dental prostheses, lasers provide promising outcomes. Among the prosthetic options, fixed partial dentures stand out for their ability to mimic natural teeth, offering both esthetic and functional features, leading to satisfactory long-term outcomes if managed properly. This review paper delves into the specific application of laser technology in the context of prosthetic rehabilitation involving fixed partial dentures. By investigating intraoral laser procedures, it contributes to understanding laser's role in improving patients' satisfaction and clinical efficiency in this field. [ABSTRACT FROM AUTHOR]

Andreas F Borkenstein, Eva-Maria Borkenstein Borkenstein & Borkenstein, Private Practice and Privatklinik der Kreuzschwestern, Graz, 8010, AustriaCorrespondence: Andreas F Borkenstein, Borkenstein & Borkenstein, Private Practice and Privatklinik der Kreuzschwestern, Kreuzgasse 35, Graz, 8010, Austria, Tel +433163313880, Email crustalith@gmx.at

This work reports the modification in the homogeneity of ablation effects with the assistance of nonlinear optical phenomena exhibited by C. albicans ATCC 10231, forming a biofilm. Equivalent optical energies with different levels of intensity were irradiated in comparative samples, and significant changes were observed. Nanosecond pulses provided by an Nd:YAG laser system at a 532 nm wavelength in a single-beam experiment were employed to explore the photodamage and the nonlinear optical transmittance. A nonlinear optical absorption coefficient −2 × 10−6 cm/W was measured in the samples studied. It is reported that multiphotonic interactions can promote more symmetric optical damage derived by faster changes in the evolution of fractional photoenergy transference. The electrochemical response of the sample was studied to further investigate the electronic dynamics dependent on electrical frequency, and an electro-capacitive behavior in the sample was identified. Fractional differential calculations were proposed to describe the thermal transport induced by nanosecond pulses in the fungi media. These results highlight the nonlinear optical effects to be considered as a base for developing photothermally activated phototechnology and high-precision photodamage in biological systems. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate the structural and chemical changes in intracanal dentin after root canal irrigation with sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA) using additional activation with a novel Er:YAG Shock Wave‐Enhanced Emission Photoacoustic Streaming (SWEEPS), ultrasonic irrigation (UI), and Nd:YAG irradiation. Root canals of extracted human premolars were instrumented with distilled water and distributed into groups according to the irrigation protocol used: Group 1: conventional needle irrigation (CI) with 3% NaOCl; group 2: CI with 15% EDTA; and group 3: CI with NaOCl+EDTA. In group 4, root canals were irrigated with NaOCl+EDTA+NaOCl using the following techniques: CI (group 4A), SWEEPS (group 4B), UI (group 4C). In group 4D, root canals were finally irradiated with Nd:YAG laser. After the irrigation, the intracanal dentin sample was collected and analyzed using spectroscope with a Fourier transformation of infrared spectrum in Attenuated total reflection technique (FTIR‐ATR) to calculate apatite/collagen ratio. Scanning electron microscopy (SEM) and energy dispersive x‐ray spectrometry (EDS) were used to determine its chemical composition. FTIR‐ATR showed no significant difference in the phosphate/amid I ratio between the control and the experimental groups (p > 0.05). SWEEPS and UI of NaOCl+EDTA+NaOCl caused the most pronounced decrease of Ca and P (p < 0.05) value compared to CI and control group, and canal wall erosion. SWEEPS and UI of NaOCl+EDTA+NaOCl caused the most pronounced decrease of Ca and P value and significant canal wall erosion. However, no difference in phosphate/amide ratio was reported among groups. Research Highlights: SWEEPS and UI of NaOCl+EDTA+NaOCl caused the most pronounced decrease of Ca and P values and significant canal wall erosion.There was no difference in phosphate/amide ratio among the irrigation protocols. [ABSTRACT FROM AUTHOR]

Introduction: Within the field of periodontology, there has been a proposal for the utilization of noninvasive laser therapy as a potential treatment for persistent periodontitis. The Laser-Assisted New Attachment Procedure (LANAP) employs an Nd:YAG laser as a specific technique. Through its interaction with endogenous chromophores, the Nd: YAG laser exhibits a selective effect on the evaporation of granulation tissue, therefore establishing a correlation with reduced bleeding. The study also examined Oxygen High-Level Laser Therapy (OHLLT). The OHLLT technique employs a high-power diode laser in combination with hydrogen peroxide solutions to facilitate the liberation of singlet oxygen, which possesses antibacterial attributes, within the periodontal pockets. The existing literature indicates their potential to promote the regeneration of tooth support tissues. Objective: The aim of this study is to assess the subjective pain levels reported by patients who have undergone surgery using the OHLLT protocol versus those who have undergone surgery using the LANAP technique. Methods: A total of 20 individuals with a stage III–IV periodontitis diagnosis were recruited for the study. The participants were randomly divided into two groups, each consisting of 10 individuals: Group 1, comprising patients treated according to the LANAP protocol, and Group 2, comprising patients treated according to the OHLLT protocol. After their initial session of nonsurgical periodontal therapy, individuals provided feedback regarding their level of pain, utilizing a Numerical Rating Scale (NRS) comprising time intervals of 0 h (T0), 6 h (T1), 12 h (T2), 24 h (T3), 48 h (T4), and 7 days (T5). The Wilcoxon–Mann–Whitney statistical test was employed to assess the variations in NRS scores between Group 1 and Group 2 at each recording period. (p ≤ 0.05). In addition, a microbiological assessment of the bacterial load in the periodontal region was conducted on all subjects using real-time PCR testing at two time points: prior to treatment (T0) and seven days post-treatment (T5). Results: The findings of this study indicate that the OHLLT group exhibited significantly lower pain levels compared to the LANAP group at all time intervals, except for the preoperative period, where no significant difference was observed (p < 0.05). Group 2 exhibited a more rapid decrease in pain, as demonstrated by a score test approaching zero within 24 h. The quantity of periodontal bacteria seen seven days post-treatment was similar between the two groups and was found to be decreased compared to the pre-treatment levels. Conclusions: The OHLLT and LANAP regimens have demonstrated efficacy in the nonsurgical management of periodontal disease. Nevertheless, it should be noted that the OHLLT approach does not subject the patient to any thermal hazards, unlike the LANAP method. The postoperative discomfort experienced following the OHLLT procedure is indeed reduced, as this technique is characterized by lower invasiveness and reduced dependence on the operator. [ABSTRACT FROM AUTHOR]

Background: The 1064 nm Q-switched neodymium-doped yttrium aluminum garnet (QS Nd:YAG) laser was developed to treat unwanted pigmentation in the skin such as lentigines caused by photoaging, and tattoos from dye/ink insertion. This laser has also been used for non-ablative epidermal rejuvenation (skin toning). Objective: To evaluate changes in skin tone, skin texture and overall improvement after a series of treatments with the QS Nd:YAG laser. Methods: Participants received seven full-face treatments with M22 or Stellar M22, a 1064 nm QS Nd:YAG laser, at 2-week intervals. The investigators and participants evaluated the improvement in skin tone and texture at 1, 3 and 6 months after the last treatment. Patient satisfaction, patient discomfort, downtime and adverse events were recorded. Histological changes in the treated area were also evaluated. Results: Thirteen women with a median age of 45 years (range, 34–61 years) were included in the study. The majority of the participants (53.9%) had skin type VI. One month after the last treatment session, 38% of participants reported good to very good improvement. This value increased to 100% participant improvement at both the 3-month and 6-month follow-up visits. The reduction in melanin index and the histological analysis demonstrated that the laser procedure contributed to a reduction in epidermal melanin content. Treatments were not associated with high levels of pain or discomfort. The most common immediate post-treatment response was erythema and edema. Most participants were satisfied with the resulting treatment outcome. Conclusion: Skin treatment with the 1064 nm QS Nd:YAG laser module on the M22 and Stellar M22 devices, using a large spot size, low fluence, moderately high repetition rate, improves skin tone and texture in patients with skin types II–VI. [ABSTRACT FROM AUTHOR]

The aim of this in vitro study was to evaluate the effect of the pre-application of a dentin-bonding agent and the application of different lasers on the prevention of tooth discoloration caused by mineral trioxide aggregate (MTA) in the presence of blood. Sixty extracted human anterior teeth were selected, with root lengths standardized to 10 mm and root canals shaped using Gates-Glidden drills #3 to #5. The samples were divided into six groups (n = 10): Group 1 with no surface treatment and Groups 2 to 6 with Optibond universal adhesive and Neodymium yttrium aluminum garnet (Nd:YAG), Erbium yttrium aluminum garnet (Er:YAG), Erbium-chromium-yttrium-scandium-gallium-garnet (Er:Cr:YSGG), and diode laser applications, respectively. Root canals were filled with fresh human blood, and ProRoot MTA and a collagen barrier were then placed. Color changes were measured with a spectrophotometer at 0, 7, 30, 90, and 180 days post MTA placement. Color differences (∆E) were analyzed using a two-factor mixed-design ANOVA with the Sidak method (p = 0.05). All treatment groups exhibited discoloration above the acceptability threshold. Although all treatment approaches exhibited less color change compared to the control group (p < 0.05), there was no significant difference among them in terms of preventing color change (p > 0.05). It was determined that none of the methods could guarantee 100% prevention of discoloration caused by MTA–blood contact. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the effects of Nd:YAG laser irradiation on the microstructures of dentin surfaces and the long-term bond strength of dentin under simulated pulpal pressure. Materials and methods: Under simulated pulp pressure, 30 freshly extracted caries-free third molars were cut into 2-mm-thick dentin samples and then divided into five groups: the control and laser groups (93.3 J/cm2; 124.4 J/cm2; 155.5 J/cm2; 186.6 J/cm2). Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), and Vickers hardness were used to analyze the surface morphology, composition, and mechanical properties of the dentin before and after laser irradiation. Another 80 caries-free third molars were removed and treated as described above, and the resin was bonded to the dentin surface with Single Bond Universal (SBU) adhesive in self-etch mode to make stick specimens. Microtensile bond strength (µTBS), confocal laser scanning microscopy (CLSM), and interfacial silver nanoleakage tests before and after 10,000 times thermocycling were then performed to analyze the bonding properties and interfacial durability of each group. Results: SEM observations revealed that the surfaces of all laser group specimens were rough with open dentin tubules. Laser irradiation altered the surface composition of dentin while removing some collagen fibers but did not affect its surface hardness or crystallographic characteristics. Furthermore, laser irradiation with an energy density of 124.4 J/cm2 significantly promoted the immediate and aging bond strengths and reduced nanoleakage compared to those of the control group. Conclusions: Under simulated pulp pressure, Nd:YAG laser pretreatment altered the chemical composition of dentin and improved the immediate and long-term bond strength. Clinical relevance: This study investigated the optimal parameters for Nd:YAG laser pretreatment of dentin, which has potential as a clinical method to strengthen bonding. [ABSTRACT FROM AUTHOR]

Background/Aim: Enterococcus faecalis is the leading cause of endodontic treatment failures. Despite various conventional disinfection approaches, microorganisms often persist in root canals. Photodynamic therapy (PDT) is an adjunct antimicrobial strategy employing a nontoxic photosensitizer (PS) and light source. This study evaluated the antimicrobial effect of PDT using an Nd:YAG laser and resveratrol (RSV) with or without pigment, and confirmed that RSV is nontoxic as a PS. Materials and Methods: We employed laser irradiation at a 3W output power, using RSV and red pigment as the PS, on an E. faecalis bacterial solution. Subsequently, colony-forming units were quantified. The impact of RSV on osteoblasts was measured using an MTT assay. Results: E. faecalis counts declined after laser irradiation. The combined application of laser irradiation with RSV, red pigment, or both showed a reduction compared to no irradiation and control groups without RSV and red pigment. The 50% cytotoxic concentration against osteoblast cells from mice incubated with RSV for 48 h was 162 µM. The value with RSV and laser was 201 µM and that with RSV and red pigment was 199 µM. The value with RSV, laser and red pigment was 357 µM. Conclusion: The combination of Nd:YAG laser irradiation and RSV as the PS with pigment was efficacious for E. faecalis elimination without inducing any toxic effects on osteoblasts. This combination holds potential as a root canal irrigation strategy. [ABSTRACT FROM AUTHOR]

Introduction The aim of the study is to compare and evaluate shear bond strength of porcelain fused to metal substructure fabricated using conventional method, surface treated with different laser modalities and direct metal laser sintering. Material and Methods Forty samples made of Co-Cr were fabricated, divided into control (Group A) and three test groups (Group B, Group C, Group D) (n=10 each). Groups A, C, D samples were made by conventional lost wax technique and B by laser sintering. All the samples were sandblasted and group C and D were surface treated with Nd: YAG and Er: YAG lasers respectively. Further, samples were veneered using 2mm of porcelain. The samples were placed in a jig and held in a universal testing machine to test the bond strength between Co-Cr and porcelain. Samples were subjected to shear stress until the fracture occurred and the results were noted. Data analysis was done using oneway analysis of variance and Post-Hoc test. Results The mean shear bond strength was highest in group D (Er: YAG laser treated Co-Cr), then group B (Laser sintered Co-Cr), then group A (Sandblasted Co-Cr) and group C (Nd: YAG laser treated Co-Cr) which was the least. Conclusion All the groups showed significant difference in shear bond strength. Er: YAG laser surface treated Co- Cr had highest bond strength to porcelain, then laser sintered Co-Cr, followed by sandblasted Co-Cr and least Nd: YAG surface treated Co- Cr. [ABSTRACT FROM AUTHOR]

Background: The discoloration potential of dental materials and applications such as vital pulp therapy also cause discoloration due to the presence of blood. Dentin tubule sealing methods could be used for the prevention of discoloration. Aim: The purpose of this study was to evaluate the effect of sealing pulp chamber walls with Nd:YAG laser against discoloration caused by tricalcium silicate‐based materials in the presence and absence of blood contamination. Design: Eighty‐one extracted human maxillary incisors were prepared and randomly divided into nine groups according to the Nd:YAG laser application, the cement to be used (NeoMTA Plus/Biodentine), and the presence or absence of blood. The color measurements were obtained with a spectrophotometer at baseline and then at the sixth (T1) and 12th (T2) months thereafter. Results: Sealing with Nd:YAG laser and placing NeoMTA Plus or Biodentine on human blood significantly increased discoloration at T1 and T2 (p <.05). Similarly, without sealing the cavity and placing NeoMTA Plus or Biodentine on human blood significantly increased discoloration at T1 and T2 (p <.05). Conclusion: Regardless of sealing the dentin tubules with Nd:YAG laser, NeoMTA Plus and Biodentine caused more discoloration in the presence of blood contamination. [ABSTRACT FROM AUTHOR]

The objective of this study was to demonstrate the oncologic efficacy of awake endoscopic laryngeal surgery in the treatment of T1-T2 glottic carcinoma. This is a retrospective study. Seventy-one patients with early glottic carcinoma (T1a- 26, T1b- 18, T2- 27) who underwent awake flexible endoscopic laryngeal surgery under local anesthesia and mild intravenous sedation were included in the study. In 64 cases (90.1%) only endoscopic tumor ablation by Nd:YAG laser (in 32.4% of cases being preceded by diathermy snare excision) was performed, and in 7 T2 cases postoperative radiotherapy was also offered. There were no complications during or after the endoscopic surgery. Ultimate control of disease, including salvage treatment, was obtained in 67 patients (94.4%). Cure without recurrence was achieved in 60 cases (84.5%). Local control without salvage radiotherapy or/and open surgery was achieved in 64 (90.1%) patients. Larynx preservation was obtained in 66 (93.0%) cases. At 5 years from the beginning of endoscopic treatment, 74.6% of the patients were alive and free of disease. The best results were obtained in the T1a group of treated patients, all the patients being free of disease with the preserved larynx. Awake endoscopic laryngeal surgery is a safe and oncologically efficient method of treatment of early glottic carcinoma that can be considered as an alternative to the traditional approach, primarily, for patients with risks/contraindications for radiotherapy, general anesthesia, and transoral microsurgery, and also for the patients who prefer to avoid general anesthesia with its related risks and would rather choose office-based laryngeal surgery. [ABSTRACT FROM AUTHOR]

The laser is used in several classic mechanical applications, such as: cutting, welding, surface treatments, etc. In the same way, laser shock peening (LSP) is an innovative surface treatment that exploits the mechanical effect of the application of pulsed laser radiation. Consequently, this generates work hardening and plastic deformation in depth. This process is implemented in different mechanical fields such as: defence, automotive, micro electromechanical systems, mechanical engineering and more particularly aeronautics. This review paper presents a generality on the LSP treatment and some of its applications. The factors of this process are displayed. Moreover, this study discusses the effects of laser shock peening on the mechanical and metallurgical properties, surface roughness, damage, and fatigue resistance of treated parts. A comparison between the LSP process and the shot peening is also exposed. As well, the various existing analytical and numerical models which allow the prediction of induced effects are analysed and compared. Moreover, the challenges and the limitations of the LSP treatment are highlighted. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the effect of the pre-application of dentin bonding agent and laser application on the prevention of tooth discoloration caused by (MTA) in the presence of blood. Fifty extracted human anterior teeth were prepared by standardizing root lengths to 10 mm and shaping root canals. Specimens were divided into five groups (n = 10) based on the treatment applied to the pulp chamber dentin wall: Group 1/no surface treatment; Group 2/Optibond FL; Group 3/Clearfil SE; Group 4/Optibond Universal adhesive application; Group 5/Nd:YAG laser application. Root canals were filled with fresh human blood below the cemento-enamel junction (CEJ), followed by ProRoot MTA, and collagen barrier placement. Color changes were monitored using a spectrophotometer at 0, 7, 30, 90, and 180 days post MTA placement. Color differences (∆E) were calculated and analyzed using two-factor mixed-design ANOVA with Sidak adjustment at p = 0.05. The degree of coloration increased with time within each group (p < 0.05). No significant differences were observed between Optibond FL and Optibond Universal within each time interval, or between Clearfill SE Bond and the control group (p > 0.05). When compared to the control group, the Nd YAG group exhibited the least degree of discoloration in all time intervals (p < 0.05). Although the Nd:YAG laser had promising results, none of the methods can guarantee a 100% prevention of discoloration resulting from tooth discoloration caused by MTA-blood contact. [ABSTRACT FROM AUTHOR]

Laser doping of n-type 4H-silicon carbide (SiC) semiconductor substrates with boron (B) using a pulsed Nd:YAG laser (λ = 1064 nm) is reported. An aqueous boric acid solution was used as a boron precursor. A simple theoretical heat transfer model was employed to select the laser processing parameters, i.e., laser power and laser-substrate interaction time, and determine the appropriate temperature to dope 4H-SiC substrates. The selected processing parameters ensured that the temperature at the laser-substrate interaction zone was below the SiC peritectic temperature to prevent any crystalline phase transformations in SiC. Fourier-transform infrared spectrometry was conducted to determine the optical properties of both undoped and boron-doped 4H-SiC substrates within the mid-wave infrared (MWIR) wavelength range (3–5 μm). Boron atoms create an acceptor energy level at 0.29 eV above the valence band in the 4H-SiC bandgap, which corresponds to λ = 4.3 μm. Boron-doped 4H-SiC substrate exhibited reduced reflectance and increased absorptance for the MWIR range. An absorption peak at λ = 4.3 μm was detected for the doped substrate. This confirmed the creation of the acceptor energy level in the 4H-SiC bandgap and, thus, doping of 4H-SiC with boron. A notable decrease in the refractive index, i.e., from 2.87 to 2.52, after laser doping of n-type 4H-SiC with boron was achieved. [ABSTRACT FROM AUTHOR]

PurposeTo explore the efficiency and safety of carbon dioxide (CO2) laser-assisted sclerectomy surgery (CLASS) in Chinese patients with glaucoma secondary to vitrectomy.MethodsThis retrospective study consisted of 16 eyes from 16 patients with glaucoma secondary to vitrectomy who underwent CLASS and were followed up for 12 months. Main outcome measures included preoperative and postoperative intraocular pressure, best corrected visual acuity (BCVA), number of anti-glaucoma medications, and postoperative surgical success rate and complications.ResultsThe postoperative IOP and number of anti-glaucoma medications used at all follow-up time point were significantly lower than those preoperatively. The difference in BCVA was not significant before and after surgery. The main complicatios were peripheral anterior synechiae (PAS) and scleral reservoir reduction, which were controlled after neodymium-doped yttrium aluminum garnet (Nd:YAG) laser, 2 (12.50%) patients underwent re-operation. The complete and total success rates at 12 months were 68.75% and 87.50%, respectively.ConclusionCLASS is a safe and effective procedure for Chinese patients with glaucoma secondary to vitrectomy. PAS and scleral reservoir reduction is a major contributor to postoperative IOP elevation, and trabecular minimally invasive perforation with the Nd:YAG laser is effective in lowering IOP and increasing scleral cistern volume.

This study synthesized titanium dioxide (TiO2) quickly and cheaply using microwaves and pulsed laser ablation. Titanium isopropoxide (Ti[OCH(CH3)2]4) was the precursor and deionized water (DIW) was the solvent and reducer for sub-micrometer particle production in microwave technique. TiO2 nanoparticles were synthesized in pulsed laser ablation liquid medium after a 5-minute preparation period in a 1200 W commercial microwave and a 1-hour annealing at 400°C. A Q-switched Nd:YAG laser with 480 mJ energy per pulse was used for 100, 200, and 300 pulses. Multiple methods, including XRD, BET, and EDX. XRD showed anatase TiO2 in microwave-synthesised nanoparticles. Pulsed laser ablation produced pure TiO2 nanoparticles with a brookite crystalline structure. In microwave BET analysis, TiO2 has a large surface area of 72.727 to 108.28 m2/g. BET analysis indicated 82.44 to 98.67 m2/g of TiO2 surface area by pulsed laser ablation. Strong titanium (Ti) and oxygen (O) peaks in microwave and pulsed laser ablation EDX tests showed nanoparticle purity.

Abstract Introduction The use of the neodymium:yttrium–aluminum-garnet (Nd:YAG) laser to treat malignant glaucoma (MG) has been described in the literature since the 1980s. However, the technique has been reported to have a short-term effect, with a notable relapse rate. In the present study, we report the efficacy and durability of a modified Nd:YAG laser treatment methodology for treatment of pseudophakic or aphakic MG. Methods Patients with chronic angle-closure glaucoma and deemed at high risk of developing post-operative MG received prophylactic peripheral iridectomy during their conventional operation beginning in 2017. When the diagnosis of pseudophakic or aphakic MG was confirmed, a thorough Nd:YAG laser capsulo/zonulo-hyaloido-vitreolysis (CZHV) was performed through iridectomy, along with standardized pre- and post-laser medications. This retrospective case series includes 14 eyes of 11 patients with MG who had surgical preset iridectomy and modified Nd:YAG laser CZHV between 2017 and 2022. Outcome measures included resolution and recurrence of MG and incidence of treatment complications. Results The mean follow-up was 27.1 ± 15.0 months (range, 12–48). Long-term resolution of MG was obtained in all included eyes at the end of the follow-up. Six eyes (42.9%) achieved long-term resolution with a single Nd:YAG laser intervention. Eight eyes (57.1%) achieved long-term resolution following two to three laser interventions, with two eyes (14.3%) experiencing recurrence. There was no complication during the follow-up. At the final visit, a significant reduction (P = 0.0001) in the mean intraocular pressure (IOP) was observed (13.1 ± 2.8 mmHg) compared to presentation (21.4 ± 6.3 mmHg). Conclusion The modified Nd:YAG laser treatment methodology is a minimally invasive option to manage pseudophakic or aphakic MG with sustained effectiveness. Reduced inflammatory reactions due to prophylactic peripheral iridectomy, rapid diagnosis, and timely treatment initiation have all contributed to the favorable outcomes associated with this modified treatment methodology.

Double layer cladding of Inconel 713LC superalloy was carried out using a 700 W pulsed Nd:YAG laser. PAC 131 powder was used as the bond coat and Metco 204NS ceramic powder as the topcoat. The effect of process parameters (laser scanning speed and focal length) was investigated on the crack formation, microstructure, and hardness. The results show that increasing the laser scanning speed leads to crack formation in the samples. Changing the focal point position reduces the dilution ratio and the formation of cracks. The clad zone has a hypereutectic microstructure and is mainly composed of chromium carbides (Cr7C3) surrounded by a eutectic structure (γ + Cr7C3). Samples containing more and coarser Cr7C3 chromium carbides are more prone to the formation and growth of cracks. Increasing the laser scanning speed from 80 to 120 mm/min raises the hardness value of the clad zone from 940 to 1040 Vickers. Another factor that increases the hardness of the clad zone is changing the focal point position. The optimal parameters for the process are as follows: a pulse width of 7.5 ms, a laser frequency of 18 Hz, a laser scanning speed of 120 mm/min, and a focal point position of 4.5 mm. The average hardness in the optimal sample is approximately 1130 Hv, which is approximately 2.6 times the hardness of the substrate. [ABSTRACT FROM AUTHOR]

Objective: This study was done to evaluate shear bond strength (SBS) and modes of failures after different surface treatment modalities on polyetheretherketone (PEEK) implant abutments. Materials and methods: Seventy-five PEEK implant abutment specimens were randomly distributed into five groups based on surface treatment methods: Group I: No treatment, Group II: methylene blue-mediated photodynamic therapy (MB-PDT), Group III: neodymium-doped yttrium aluminum garnet (Nd:YAG) laser, Group IV: Sulfuric acid (H2SO4), and Group V: Sandblasting (Sb). The measurements for SBS and failure modes for PEEK implant abutment specimens were evaluated via Universal Testing Machine and Stereomicroscope, respectively. Two-way analysis of variance and Tukey's post-hoc test (p > 0.05) were used for the statistical analysis. Moreover, the Shapiro-Wilk normality test was also performed for normality. Results: The SBS mean values and standard deviations in megapascals (MPa) for PEEK abutment specimens with different surface pretreatment groups are shown in Table 1 and Fig. 1. The control group had the lowest SBS (9.67 - 2.1 MPa), while the highest SBS was observed in Group II (MB-PDT; 17.21 - 1.32 MPa). SBS values for Group IV (H2SO4; 15.83 - 0.63 MPa) and Group III (Nd:YAG laser; 16.91 - 2.10 MPa) were similar to Group II (MB-PDT; p > 0.05). The SBS values for the sandblasted specimens (13.90 - 1.87 MPa) were not significantly different from the control group (p > 0.05). Conclusions: The PEEK implant abutment surfaces treated with MB-PDT and Nd:YAG laser expressed significantly improved SBS. [ABSTRACT FROM AUTHOR]

Introduction: The use of the neodymium:yttrium–aluminum-garnet (Nd:YAG) laser to treat malignant glaucoma (MG) has been described in the literature since the 1980s. However, the technique has been reported to have a short-term effect, with a notable relapse rate. In the present study, we report the efficacy and durability of a modified Nd:YAG laser treatment methodology for treatment of pseudophakic or aphakic MG. Methods: Patients with chronic angle-closure glaucoma and deemed at high risk of developing post-operative MG received prophylactic peripheral iridectomy during their conventional operation beginning in 2017. When the diagnosis of pseudophakic or aphakic MG was confirmed, a thorough Nd:YAG laser capsulo/zonulo-hyaloido-vitreolysis (CZHV) was performed through iridectomy, along with standardized pre- and post-laser medications. This retrospective case series includes 14 eyes of 11 patients with MG who had surgical preset iridectomy and modified Nd:YAG laser CZHV between 2017 and 2022. Outcome measures included resolution and recurrence of MG and incidence of treatment complications. Results: The mean follow-up was 27.1 ± 15.0 months (range, 12–48). Long-term resolution of MG was obtained in all included eyes at the end of the follow-up. Six eyes (42.9%) achieved long-term resolution with a single Nd:YAG laser intervention. Eight eyes (57.1%) achieved long-term resolution following two to three laser interventions, with two eyes (14.3%) experiencing recurrence. There was no complication during the follow-up. At the final visit, a significant reduction (P = 0.0001) in the mean intraocular pressure (IOP) was observed (13.1 ± 2.8 mmHg) compared to presentation (21.4 ± 6.3 mmHg). Conclusion: The modified Nd:YAG laser treatment methodology is a minimally invasive option to manage pseudophakic or aphakic MG with sustained effectiveness. Reduced inflammatory reactions due to prophylactic peripheral iridectomy, rapid diagnosis, and timely treatment initiation have all contributed to the favorable outcomes associated with this modified treatment methodology. [ABSTRACT FROM AUTHOR]

Introduction Dermatophytosis is a superficial fungal infection, which is limited to the fully keratinized layer of the skin (stratum corneum), nails and hair. A noticeable increase in number of patients with recurrent dermatophytosis was observed during the last few years, which differs from the classical mode of presentation of this infection by being symptomatic, more inflammatory, widespread, running a recurrent course and highly resistant to conventional treatments. Objective To evaluate the outcome of using Q-switched Nd:YAG laser (1,064-nm) as a new treatment modality for this vexing problem. Methods Twenty patients with thirty-three lesions of localized recurrent dermatophytosis with positive mycological study were collected, all of them were treated with Q-switched Nd:YAG laser (1,064-nm) 4 sessions, one week apart. The patients were followed up weekly until the end of first month, then monthly for 6 months. Results All patients showed excellent response to treatment with clinical cure rate of (100%). One patient had relapse (3.03%). Conclusion Q-switched Nd:YAG laser (1,064-nm) was found to be a safe and effective treatment of recurrent dermatophytosis that has been failed to respond to different types of systemic and topical antifungal drugs with excellent result and remarkable reduction in recurrence rate. [ABSTRACT FROM AUTHOR]

Objective To compare the efficacy of Eflornithine and Nd:YAG laser in combination therapy versus Nd:YAG laser alone in treating patients of idiopathic facial hirsutism. Methods This randomized controlled trial was done from 9th April 2019 to 8th December 2019 in Dermatology department, Services Hospital, Lahore. Total 80 female with idiopathic hirsutism, 18-45 years of age, randomized into two groups. Group A was treated with combination therapy of Eflornithine and Nd:YAG laser and Group B was given Nd:YAG laser alone. The patients were followed at 4 weeks interval till 24 weeks to observe efficacy. Final assessment was done on 8th visit (taking baseline at 0 and 24th week as final session). Hair counts were done in 1 cm2 surface area of the treated area. Results Both groups A and B had 40 patients each, from 18-45 years with mean age of 29.05±5.89 years. The mean ages of patients in group A and B was 29.10±6.03 and 29.03±5.82 years respectively. Majority of the patients 52 (65.0%) were between 18 to 30 years of age. Efficacy of Group A (Eflornithine and Nd:YAG laser) was seen in 37 (92.50%) patients while in Group B (Nd:YAG laser alone) was seen in 29 (72.50%) patients (p-value = 0.018). Conclusion This study concluded that combination of eflornithine and Nd:YAG laser is more efficacious than that of Nd:YAG laser alone in treatment of idiopathic hirsutism. [ABSTRACT FROM AUTHOR]

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Background Immature hypertrophic scar complicated with contracture, disability, disfigurement, social embarrassment, pain, itching, residual scar, and prolonged maturation period. Various treatments for immature hypertrophic scar are used with limitations for each treatment. Objective To evaluate the efficacy and safety of combined fractional carbon dioxide (CO2) and Neodymium-doped Yttrium Aluminum Garnet (Nd:YAG) lasers for the treatment of immature hypertrophic scar both clinically and histopathologically. Patients and methods Total of 30 patients with single or multiple immature hypertrophic scars. The single scar was not less than 14cm in length. In the same patient, single or multiple scars were divided randomly into treated areas and control areas. The treated areas were submitted to 5 sessions of fractional CO2 laser combined with long pulsed Nd:YAG laser, one month in between sessions, the control areas did not receive any treatment. Vancouver Scar Scale (VSS) and patient and observer scar assessment scale (POSAS) were used for clinical evaluation before, 3, and 6 months after treatment. Collagen area percent, elastin area percent, and epidermal thickness were assessed histopathologically before and 3 months after treatment. Results The scar areas treated with combined fractional CO2 laser and long pulsed Nd:YAG laser showed superior significant clinical improvement with VSS and POSAS than areas did not receive any treatment (except for the pigmentation parameter of both VSS and POSAS), especially 6 months after last treatment without significant side effects for laser therapy. Opinions of the patients showed superior significant improvement in laser treated areas than areas did not receive any treatment. Epidermal thickness, collagen area percent and elastin area percent showed superior significant improvement in laser treated areas than areas did not receive any treatments three months after last laser session. Conclusion Combined treatment of immature hypertrophic scar with fractional CO2 and Nd: YAG lasers is effective, tolerable, and safe. [ABSTRACT FROM AUTHOR]

Every commercial NiTi (Nitinol) Shape Memory Alloy (SMA) has its own transformation temperatures, which may cause limitations in ever-growing demands for the application of these alloys in novel engineering designs. Among various methods proposed to achieve multiple functional characteristics, laser processing offers effective solutions in locally controlling the transformation properties of NiTi parts. The current work describes the application of laser technique followed by post-processing to locally alter transformation temperatures and impose phase transition for thick NiTi wires. To this end, various laser parameters are applied, and the influences of peak power and pulse width on the functional, microstructural, and mechanical properties of laser processed samples are studied. A four-sided laser processing protocol is proposed to process almost the whole cross section of thick Nitinol wires. It is also shown that postprocessing heat treatment is required to recover the shape memory properties of asprocessed Nitinol specimens. The transformation temperatures of the final processed Nitinol wire increase by about 50 °C compared to those of the unprocessed base material. [ABSTRACT FROM AUTHOR]

Microstructure evolution and physical property differences in tungsten inert gas (TIG) welding and laser beam welding (LBW) with a Nd:YAG laser of Q235 steel and 304 stainless steel in qualified welded joints were obtained through single factor experimental design. The results showed that the microstructure of the weld zone (WZ) is composed of lath martensite, and carbon migration occurred at the interface in the Q235 steel. Under the condition of full penetration of the welded joint, the tensile specimens fractured on the side of Q235 steel, indicating that the strength of the welded joint is higher than that of the Q235 base material (BM). These fracture morphologies presented the characteristics of ductile fracture. The distribution of microhardness in each region of welded joint in terms of heat affected zone (HAZ), BM and WZ was WZ > 304 side HAZ > 304 BM > Q235 side HAZ > Q235 BM. [ABSTRACT FROM AUTHOR]

In this work, zinc oxide–based piezoelectric nanogenerator (PENG) over the flexible Kapton polyimide (PI) substrate is developed. The device performance is improved by laser texturing of PI substrate, which increases the effective surface area of PI and adhesivity of ZnO thin film with PI substrate to improve the reliability and life span of the device. The untextured PI‐based PENG generates a peak‐to‐peak output voltage, current, and power of 6 V, 420 nA, 2.42 μW, respectively, which increases to 15.8 V, 790 nA, and 12.51 μW, respectively, on using textured PI obtained by 60% laser spot overlap. On further increasing the laser spot overlap to 80%, the peak‐to‐peak output voltage, current, and power improve to 22.2 V, 1210 nA, and 26.88 μW, respectively. Therefore, as compared to the untextured‐PI‐based PENG, laser‐textured‐PI‐based PENG is a promising candidate for energy‐harvesting applications. [ABSTRACT FROM AUTHOR]

The results of measurements of temporal parameters of a Q-switched Nd:YAG laser with an intraresonator optical parametric oscillator and high harmonic and sum frequency cascade generation are presented. Pulse durations by a level of 0.5 and front durations by levels of 0.1–0.9 of monopulses peak power of RGB-laser monopulses in the spectral range from 355 to 1572 nm using an LFD-2A germanium avalanche photodiode and Thorlabs DET08CL/M InGaAs pin-diode with a LECROY (2.5 GHz) digital oscilloscope were measured. The results may be used in air- and sea-LIDARs. [ABSTRACT FROM AUTHOR]