Evaluation of the impact of the latest root canal disinfectant, that is carbon quantum dots (CQDs), synchronized microbubble-photodynamic activation (SYMPA), and Nd: YAG laser along with ethylenediaminetetraacetic acid (EDTA) as a final irrigant on the Marten hardness (MH), smear layer (SL) removal, and extrusion bond strength (EBS) of zirconia post to the canal dentin. Eighty intact single-rooted premolars were obtained and disinfected using 0.5% chloramine-T solution. Root canal preparation was performed using ProTaper files followed by obturation. The post space was prepared for prefabricated zirconia post and all the teeth were randomly divided into four groups based on the disinfection used (n = 20 each) Group 1: 5.25% NaOCl + 17% EDTA (Control), Group 2: Nd: YAG laser + 17% EDTA, Group 3: SYMPA + 17% EDTA, and Group 4: CQDs + 17% EDTA. MH, SL removal, and EBS of zirconia post-bonded to root dentin were performed using a microhardness tester, scanning electron microscope (SEM), and universal testing machine, respectively. Both intragroup and intergroup comparisons were performed using one-way analysis of variance (ANOVA) and posthoc-Tukey test for significant difference (p < .05). Group 2 samples (Nd: YAG laser + 17% EDTA) (0.24 ± 0.06 GPa) exhibited highest values of MH. Samples in group 3 (SYMPA + 17% EDTA) treated teeth unveiled the lowest MH scores (0.13 ± 0.02 GPa). Moreover, the coronal third of Group 3 specimens (SYMPA and 17% EDTA) (1.54 ± 0.31) eliminated SL from the canal with the greatest efficacy as well as presented the highest EBS (10.13 ± 0.69 MPa). However, the apical third of Group 1 samples (5.25% NaOCl + 17% EDTA) (2.95 ± 0.33) exhibited the least efficient elimination of SL from the radicular dentin as well as the lowest bond strength (5.11 ± 0.19 MPa) of zirconia post to the dentin. The SYMPA technique with 17% EDTA proved highly effective in removing the SL from canal dentin and enhancing the EBS of zirconia posts. The least preferable method for SL removal and MH improvement was found to be 5.25% NaOCl + 17% EDTA. CQDs and Nd: YAG laser demonstrated satisfactory smear layer removal properties from the canal, along with achieving appropriate bond strength of zirconia posts. RESEARCH HIGHLIGHTS: Nd: YAG laser and 17% EDTA as canal disinfectant exhibited the highest values of MH. Specimens irrigated with SYMPA and 17% EDTA eliminated SL from the canal with the greatest efficacy. The coronal third of Group 3 (SYMPA + 17% EDTA) samples unveiled the highest zirconia post-bond integrity score to the canal dentin. Cohesive failure was a dominant failure type among different experimental groups.

BACKGROUND: Vitreous floaters are a common ocular condition that affects individuals of all ages. Although vitreous floaters are typically benign, they can significantly impair visual acuity and quality of life. Laser vitreolysis, which uses an Nd: YAG laser to vaporize collagenous vitreous opacities, is increasingly being used as a treatment option. However, there is currently a lack of evidence regarding its efficacy and the appropriate timing of its application. This study aims to evaluate the efficacy and safety of early intervention with YAG laser vitreolysis in treating symptomatic vitreous floaters.
METHODS: The present study is a randomized, controlled, double-blind clinical trial. A total of 70 participants with symptomatic floaters for 1 month were prospectively recruited. These participants will be randomly assigned to two groups, with 35 individuals in each group: the early treatment group and the delayed treatment group. Participants assigned to the early treatment group will undergo YAG laser vitreolysis immediately, followed by a sham laser treatment 3 months later. On the other hand, participants assigned to the delayed treatment group will receive a sham laser treatment and then undergo YAG laser vitreolysis 3 months later. The follow-up time points will be 1, 3, 6, and 12 months from randomization. Primary outcomes will be participants\' self-reported improvement in visual disturbance on a scale of 1 to 10 and their scores on the National Eye Institute Visual Functioning Questionnaire 25 (NEI VFQ-25). Secondary outcomes will be an objective evaluation of the effectiveness of the treatment in reducing vitreous floaters through OCT and fundus photography and tracking any adverse events related to the eyes or overall health.
CONCLUSIONS: This clinical trial aims to evaluate the effectiveness of YAG laser vitreolysis in treating symptomatic vitreous floaters and assess the safety of performing early intervention with YAG laser vitreolysis.
BACKGROUND: ClinicalTrials.gov NCT05800353 . Registered on 10 March 2023.

Full clearance and no side effects method of treating enlarged veins was successfully accomplished by one laser session. This is the ambition and dream of both dermatologists and patients. Most vascularity treatment protocols had shown some unpleasant adverse effects. The purpose of the present work is to work out, in advance, the accurate dose of laser pulse duration and fluence in order to treat varicose veins in the face, arms and legs with no adverse effects. This mission required the calculation of the exact rise in temperature of the enlarged vein; prior to laser treatment. These pre-calculated temperature rise values were tested on 20 subjects in order to have the best clinical outcomes; using fundamental frequency (1064 nm) pulsed Nd: YAG laser. This work necessitated the use of pulse length (15-30 ms), spot size (3, 5 mm), fluence (110-190 J/cm2) and skin cooling temperature (3-18 °C). Cooling of the skin before and after the treatment was needed to guarantee ultimate impactful results without side effects.

To compare and analyze the clinical therapeutic effects of sodium hypochlorite combined with Nd: YAG laser and sodium hypochlorite alone for root canal disinfection in patients with pulpitis.
Patients with pulpitis were divided into control group and observation group according to random number table method. Both groups received root canal treatment, while the control group received root canal irrigation with 1% sodium hypochlorite. The observation group was irrigated with 1% sodium hypochlorite combined with Nd: YAG laser. Periodontal index, inflammatory index, life quality score and bacterial infection clearance rate of the two groups were compared before and 3 months after treatment.
The total effective rate of the observation group was 95.35%, which was higher than that of the control group 79.07% (p < .05). After 3 months of treatment, the periodontal index and inflammation level of both groups decreased, and the observation group was lower than that in the control group (p < .05). The life quality score and infection clearance rate of observation group were significantly higher than control group (p < .05).
Compared with root canal irrigation with 1% sodium hypochlorite alone, sodium hypochlorite combined with Nd: YAG laser for root canal disinfection can significantly improve the therapeutic effect, relieve inflammatory reaction, and decrease bacterial infection.

This study aimed to evaluate the levels of tumour necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β) and interferon-gamma (IFN-γ) with asymptomatic apical periodontitis (AP). A total of 60 participants were randomly divided into two groups: the conventional irrigation (control) and the Nd: YAG laser irradiation. The interstitial fluids were obtained after root canal cleaning (day 0) and 1 week later (day 7). The TNF-α, IL-1β and IFN-γ levels were assayed using the enzyme-linked immunosorbent assay. The Mann-Whitney U, continuity correction chi-square, Pearson chi-square and Fisher exact tests were used. An increased level of cytokines on day 7 in the control group was observed, without statistically significant differences (p > 0.05). All cytokine levels decreased over time in the laser group. Only the IL-1β level showed a significant difference (p < 0.05). Nd: YAG irradiation has a positive effect on decreasing the proinflammatory cytokine level and may help to control infection in teeth with AP.

Background and Objectives: Asian patients with Fitzpatrick skin type III-IV are a less studied subtype of patients in the medical literature. Q-Switched, 1064 nm neodymium-doped yttrium aluminum garnet (Nd: YAG) laser with a fractionated beam profile (QSF) is a new modality that was reported to be effective in the treatment of scars. This study aims to evaluate the efficacy and safety of QSF Nd: YAG laser in treating scars in Asian patients. Materials and Methods: A total of 29 Subjects were treated with 1064 nm QSF laser. Each patients had three treatments with a fractionated microlens array handpiece every 8 weeks). Efficacy of treatment was evaluated using the Goodman and Baron\'s quantitative grading scale before and 3 months after the last treatment. Results: All 29 patients treated had significant improvement of acne scars according to Goodman and Baron\'s Quantitative Global Acne Scarring Grading System. No side effect has been observed except some minor erythematous reactions in three patients. Conclusions: Our results confirm that the 1064 nm QSF Nd: YAG laser is a safe and effective technique for treating scars in Asians.

Becker\'s nevus (BN) is a cutaneous hamartoma of benign nature that develops through adolescence and affects mostly young men. The nevus is usually located unilaterally and is characterized by hypertrichosis and hyperpigmentation. Despite recent advances in treatment modalities, no effective treatment has been established for BN hyperpigmentation. We sought to assess the efficacy and safety of fractional Erbium: YAG 2940 nm and Q-switched Nd: YAG 1064 nm lasers in the treatment of BN hyperpigmentation. Twenty-three patients with BN were included in a prospective, randomized-controlled, observer-blinded, split-lesion comparative technique trial. In each patient, two similar square test regions were randomized to either be treated with a fractional Erbium: YAG 2940 nm laser or with a Q-switched Nd: YAG 1064 nm laser. Each patient was treated with three sessions at six-week intervals. At the follow-up, clearance of hyperpigmentation was assessed by physician global assessment, visual analogue scale, grade of improvement, patient global assessment, and patient satisfaction. Regions treated with the fractional Erbium: YAG 2940 nm laser demonstrated significantly better improvement compared to ones treated with the Q-switched Nd: YAG 1064 nm (p-value = 0.001) laser. Adverse effects such as repigmentation and hypertrophic scarring were not reported during the follow-up period. The outcomes were cosmetically acceptable with overall high satisfaction among the included patients. Our data suggest a superior role for the fractional Erbium: YAG (2940 nm) laser in the treatment of BN hyperpigmentation compared to the Q-switched Nd: YAG (1064 nm) laser, along with being a safer method and having no reported side effects.

BACKGROUND: Every lobectomy requires the transection of the interlobar fissure. Resection surfaces must be airtight in order to avoid leakage and infection. Using an ex vivo model based on porcine lung, we compared three techniques with respect to initial airtightness at different inspiratory pressures.
METHODS: In the first technique (group 1), we transected the interlobar fissure with a monopolar cutter and overstitched the edges of the resection area with a monofilament thread. In the second technique (group 2), the interlobar fissure was cut with a stapling device. In the third technique (group 3), the interlobar fissure was cut using a laser fibre connected to an Nd: YAG laser. The resection areas were not overstitched; 15 transections were performed in each group.
RESULTS: In group 1, three parenchymatous bridges leaked starting at a pressure of 25 mbar. In the other two groups, all preparations were airtight at this pressure. If the ventilation pressure was increased up to 40 mbar, all seams in group 1 were leaky at a pressure of 35 mbar. Four staple seams were airtight at a pressure of 40 mbar. In group 3, 11 preparations (73.3 %) were airtight up to a pressure of 40 mbar.
CONCLUSIONS: Based on our results, the use of an Nd: YAG laser is suitable for the transection of the interlobar fissure. In effect, this technique compares well with the other techniques examined.

Laser welding is an innovative method that is frequently used and required by different disciplines and represents a technique of choice in a wide range of applications due to important advantages such as precision, speed, and flexibility. However, the welding method must be used properly otherwise it may deteriorate the mechanical properties of the welded metal and its environment. Therefore, the laser parameters should be precisely determined and carefully applied to the sample. The primary objective of this study was to investigate and propose optimal welding parameters that should be adjusted during the neodymium-doped yttrium aluminum garnet (Nd: YAG)-pulsed laser welding of austenitic stainless steel 316L in an air welding environment by using Argon shielding gas and in wet welding settings in serum medium. The investigation of the welding process in serum medium was conducted in order to propose the most suitable welding parameters being important for future possible medical applications of laser welding in in-vivo settings and thus to investigate the possibilities of the welding process inside the human body. In order to evaluate the quality of welding in air and of wet welding (in serum), a detailed parameter study has been conducted by variation of the laser energy, the welding speed and the focal position. The relationship between the depth of penetration and specific point energy (SPE) was also evaluated. The microstructure of the welded metal was examined by an optical microscope and scanning electron microscope (SEM). Based on the microscopy results, it was found that the largest depth of penetration (1380 µm) was achieved with 19 J laser energy in air medium, while the depth reached the largest value (1240 µm) in serum medium at 28 J laser energy. The increasing energy level showed opposite behavior for air and serum. The results of our study imply that when welding of 316L stainless steel is implemented properly in the body fluid, it would be a promising start for future in-vivo studies.

Lichen amyloidosis (LA) is a type of primary localized cutaneous amyloidosis characterized by multiple localized, hyperpigmented, grouped papules, in which the deposition of amyloid materials from altered keratinocytes usually resists to current treatments. We presented two LA patients with non-satisfactory results of topical treatments. After the first treatment using 1064-nm Nd: YAG picosecond (ps-Nd:YAG) laser, there was an improvement with persistence up to 3-month follow up after five sessions of 4-week interval, as well as a decrease in number, thickness, and darkness of lesions from clinical and dermoscopic evaluation. Thus, the ps-Nd:YAG laser could be efficacious for LA treatment.