The present work aimed at assessing chemical, topographical, and morphological changes induced by Nd : YAG laser treatment of dental enamels by means of energy dispersive X-ray spectroscopy (EDS), ...atomic force microscopy (AFM), and scanning electron microscopy (SEM). Fifteen human enamel specimens were obtained, three of samples were kept untreated as a control while the others twelve samples were equally divided into four groups where each group have a three samples according to treating approach as: G1:(untreated);G2: (treated with Nd:YAG laser, 100 mJ/pulse,10 Hz/1064nm); G3(treated with Nd:YAG laser, 500 mJ/pulse, 10 Hz/1064nm); G4(treated with Nd:YAG laser 1000 mJ/pulse, 10 Hz/1064nm), and finally G5(treated with Nd:YAG laser, 1000 mJ/pulse, 10 Hz/532nm) respectively. Beside many craters and cracks, the AFM results showed fractures with depths of 19.23 nm, 174.7 nm, 216.9 nm, 207.4 nm and 156.5 nm and width of 559.2 nm, 833.4 nm, 1115 nm, 695.0 nm, and 5142 nm for all Groups respectively. The highest surface roughness was found in G5 with 111.4 nm while the lowest surface roughness was found in G1 to be 14.3 nm. The inside surface of the fissures was also rough. The SEM micrographs revealed modifications to the morphology. EDS was used to measure the phosphorous (P), calcium (Ca), oxygen (O), and carbon (C) percentages presented in crater areas and their surroundings, Ca, P, O, and C levels were observed to vary significantly at the crater and its rim, a lower percentage of C wt% were realized corresponding to laser treatment of 1000 mJ/Pulse laser energy. However, it was not feasible to recognize a specific chemical arrangement in the craters. It is also concluded that the higher depth and particular edge of ablated part when teeth were irradiated by laser with 1000 mJ/10Hz/1064nm.
Background
A few studies discussed the factors correlated to response in laser treatment of onychomycosis.
Objective
This study aimed to seek big toenail onychomycosis features that correlate with ...response to 1064 nm Nd: YAG laser treatment.
Methods
This single‐center, retrospective study included patients who had only one big toenail onychomycosis, with a confirmed mycological diagnosis and/or a high clinical suspicion. Patients had three sessions 1 month apart. The following characteristics were collected from the patients' files: age, sex, smoking and arterial hypertension statuses, results of baseline mycological culture, Onychomycosis Severity Index (OSI) score at baseline and at the end of the 6‐month follow‐up, as well as the reported side effects.
Results
We included 105 patients, 86 women and 19 men, with a mean age of 43 years. Demographics have shown that 73.6% of patients were smokers, 17.9% had arterial hypertension, 61.9% had a culture positive for Trichophyton species, and 9.4% had a culture positive for Candida species. According to the OSI score, onychomycosis was mild in 18.9%, moderate in 39.6%, and severe in 41.5% of patients. At 6 months, clinical cure was achieved in 57.1% of patients.
Conclusion
The OSI decrease after 3 sessions of Nd: YAG laser was significantly more important in women and in patients with positive mycology culture, smaller affected area of the nail, no subungual hyperkeratosis, and no nail matrix involvement. Age, smoking, hypertension, and side effects were not shown to significantly correlate with the decrease of the OSI score.
Background
Our previous research found that Q‐switched 1064‐nm Nd: YAG laser (1064‐QSNYL) induces skin collagen synthesis by activating TGFβ1/Smad3/p38MAPKs pathway. Moreover, a lot of studies shown ...that MicroRNAs (miRNAs) contribute to regulate collagen synthesis and skin barrier. Therefore, we intend to explore the mechanism of 1064‐QSNYL on collagen synthesis and skin barrier through miRNAs.
Methods
We predicted the upstream miRNAs of TGFβ1 by bioinformatics databases, and verified them through dual‐luciferase reporter genes and Western blotting. The expression of collagen, skin barrier‐related protein K10 and filaggrin, TIMP‐1, and MMP‐2 were detected by RT‐qPCR and Western blotting, respectively. Moreover, we detected moisture content, elasticity value, TEWL value, SOD vitality, and hydroxyproline content to evaluate skin barrier of mice. H&E staining to observe the change of dermis thickness and inflammation and infiltration of mice skin.
Results
The results shown that TGFβ1 was target gene of miR‐663a. Moreover, we found that 1064‐QSNYL activated TGFβ1/smad3/p38MAPK pathway by down‐regulating the expression of miR‐663a in HaCaT, HDF cells, and mice, thereby promoting expression of Collagen I, Collagen IV, TIMP‐1, K10, and filaggrin and inhibiting MMP‐2. Furthermore, 1064‐QSNYL contributed to moisture content, elasticity, SOD vitality, and hydroxyproline content via miR‐663a to activate TGFβ1/smad3/p38MAPK pathway.
Conclusions
In summary, this study found for the first time that 1064‐QSNYL contributed to collagen synthesis and skin repair via miR‐663a to regulate TGFβ1/smad3/p38MAPK pathway, thereby achieving skin rejuvenation.
Despite multiple individual studies proving efficacy of grid fractional monopolar radiofrequency (Grid RF) and near‐infrared irradiation 1064‐nm long‐pulsed neodymium:YAG laser (Laser Genesis), there ...is a lack of controlled comparative trials between these devices. This study aims to compare the efficacy and safety of Grid RF versus Laser Genesis in the treatment of periorbital rhytides. This is a randomized, single‐blind, split‐face, prospective study. Eight patients with moderate to severe periorbital rhytides were treated with either Grid RF or Laser Genesis on each side of the face. Photographic and live assessment with the Lemperle Wrinkle Assessment grading scale was compared after 2 months. Difference in scores between Grid RF vs Laser genesis groups after 2 months was not statistically significant (P = 0.244). Each group showed statistically significant improvement months post‐procedure (P < .05). Immediate adverse effects and satisfaction scale were similar for both groups (P > .05). At 2 months follow‐up, no adverse effects were seen. Grid monopolar radiofrequency (Grid RF) vs near‐infrared radiation 1064 nm long‐pulsed Nd‐YAG laser (Laser Genesis) were equally efficacious, safe, and well‐tolerated among patients in the treatment of periorbital wrinkles (P > .05).
Background
The treatment of dilated facial pores is difficult, and the ideal modality is not established yet. Different ablative and nonablative lasers have been used in the treatment of dilated ...pores with variable outcomes.
Aim
To evaluate and compare the efficacy of fractional CO2 laser versus carbon‐assisted Q‐switched Nd: YAG laser in dilated facial pores.
Methods
The study included 80 patients with dilated pores divided into two groups each containing 40 patients. Group (A) had fractional CO2 laser treatment, and group (B) received Q‐switched Nd: YAG laser treatment after the application of a carbon solution on the face. The treatment was repeated monthly for a total of 3 sessions. Objective and subjective assessments of the clinical outcome were performed.
Results
Both modalities significantly improved the dilated pores; however, the clinical response was statistically higher and the improvement was maintained for a longer duration of time in the factional laser group compared with the carbon‐assisted Q‐switched Nd: YAG laser group (p = 0.01). The downtime was significantly lower in the Q‐switched Nd: YAG laser group, and the patients’ satisfaction rates were comparable in both groups.
Conclusion
The two laser systems appear to be effective, safe, and well‐tolerated in the treatment of dilated pores. The fractional CO2 laser was associated with a significantly higher and more prolonged clinical response.
Introduction
Melasma is an acquired pigmentary disorder which currently has no definitive treatment. Although topical drugs containing hydroquinone are the basis of treatments, they are usually ...associated with recurrence. We aimed to evaluate the effectiveness and safety of monotherapy with topical methimazole 5% versus combination of Q‐Switched Nd: YAG Laser and topical methimazole 5% in patients with refractory melasma.
Methods
A total of 27 women with refractory melasma were included. We applied topical methimazole 5% (once a day) with three passes of QSNd: YAG laser (Wavelength: 1064 nm, pulse energy: 750 mJ, fluence: 1.50 J/cm2, spot size: 4 × 4 mm, hand piece: fractional, JEISYS company) for six sessions on the right half of the face, and topical methimazole 5% (once a day) on the left half of the face, for each patient. The treatment course was 12 weeks. Evaluation of effectiveness was done with the Physician Global Assessment (PGA), Patient Global Assessment (PtGA), Physician satisfaction (PS), Patients satisfaction (PtS), and mMASI score.
Results
PGA, PtGA, and PtS were not significantly different between the two groups at any time (p > 0.05). PS in the laser plus methimazole group was significantly better than methimazole group at 4th, 8th, and 12th weeks (p < 0.05). The rate of PGA improvement in the combination group was significantly better than the monotherapy over time (p < 0.001). The changes of mMASI score between the two groups did not significantly differ at any time (p > 0.05). There was no significant difference in the adverse events between the two groups.
Conclusion
Combination therapy with topical methimazole 5% and QSNY laser can be considered as an effective way to treat refractory melasma.
•Laser welding parameters effect on high manganese steel properties were considered.•Response surface methodology was used to develop mathematical models.•Free defect weld with best strength obtained ...by using optimal parameters.•The mechanical properties and microstructure of optimized specimen was studied.•Laser power has the major effect on responses.
In the present study, the microstructural and mechanical properties of laser beam-welded thin sheet twinning-induced plasticity (TWIP) steel were investigated. The pulsed neodymium: yttrium-aluminum-garnet (Nd: YAG) laser beam welding process parameters were modeled and optimized based on experimental data and statistical analysis using response surface methodology (RSM) technique. Process parameters range, i.e. the power input (2000–3000 W), welding speed (0.2–1 mm/min), and spot size (0.3–0.7 mm) were selected properly in order to obtain the desired mechanical properties. Main effects of each factor along with interaction effect with other factors were determined quantitatively. The predicted and actual values of the mechanical properties compared using analysis of variance (ANOVA) in order to verify the adequacy of the developed model. Optimal laser beam welding parameters were identified as the power input, welding speed and spot size of 2586 W, 0.53 mm/min, and 0.48 mm, respectively. Using parameters in the optimal conditions, a welding joint with tensile load of 2001 N (% 94 strength of the base metal) was obtained. In addition, the welding zone with an average grain size coarser than the one for the base metal and a random texture was identified.
Background: Melasma is a common dermatosis in both men and women showing varying degrees of success with treatment. Relapse of pigmentation in melasma after treatment is a common problem in dark skin ...types that necessitates treatment with novel alternative modalities with better efficacy. Aim: To compare the effectiveness of intradermal platelet-rich plasma vs. 1064 nm Qs Nd-YAG in patients of melasma in a split face comparative study conducted in a Dermatology center over a period of 6 months. Methods: A comparative split face prospective study of 20 female patients of Fitzpatrick skin type IV-V with mixed resistant type of melasma and bilateral involvement of the face were enrolled for the study. Platelet-rich plasma (PRP) was injected intradermally at 2 weeks interval for seven sittings in one half of the face and Qs Nd-YAG was done every week for 12 weeks on the other half of the face. The results were assessed clinically by Hemi-modified MASI score at the end of every 2 weeks. Patients were counselled to continue strict sun protection measures. Patient satisfaction was noted at baseline, 4 weeks, 8 weeks, and 12 weeks. Patients were followed up for 3 months to see for any relapse of the pigmentation and the follow-up results were compared for both modalities of treatment. Results: Comparison of Hemi-mMASI score in both groups showed statistically significant improvement of pigmentation on completion (i.e., at the end of 12 weeks) and not in successive follow-up results every 2 weeks. The subjective assessment was made by PGAIS (Physician global aesthetic improvement scale). Patient satisfaction levels (assessed by SGAIS-Subject global aesthetic improvement scale) also showed significant improvement in successive weeks of treatment in both the groups. Few patients had mild redness and burning post procedure which resolved spontaneously after few hours. Patients were followed up for 3 months to see for reappearance of melasma. The split side treated with PRP showed less reappearance of pigmentation than the side treated with Qs Nd-YAG laser. Conclusion: From this study we concluded that PRP shows a significant improvement in pigmentation in mixed resistant melasma in 12 weeks of treatment with less chances of relapse after 3 months of treatment as compared with Qs Nd-YAG laser. PRP may be used as a first-line treatment in mixed, resistant melasma cases and also as an excellent maintenance therapy in these cases. Limitations: Desired sample size could not be achieved and a longer follow-up period of 6 months could not be materialized.
This study investigated the effect of neodymium-doped yttrium aluminum garnet (Nd: YAG) laser irradiation on surface properties and bond strength of zirconia ceramics. Specimens of zirconia ceramic ...pieces were divided into 11 groups according to surface treatments as follows: one control group (no treatment), one air abrasion group, and nine laser groups (Nd: YAG irradiation). The laser groups were divided by applying with different output power (1, 2, or 3 W) and irradiation time (30, 60, or 90 s). Following surface treatments, the morphological characteristics of ceramic pieces was observed, and the surface roughness was measured. All specimens were bonded to resin cement. After, stored in water for 24 h and additionally aged by thermocycling, the shear bond strength was measured. Dunnett's
t
test and one-way ANOVA were performed as the statistical analyses for the surface roughness and the shear bond strength, respectively, with α = .05. Rougher surface of the ceramics could be obtained by laser irradiation with higher output power (2 and 3 W). However, cracks and defects were also found on material surface. The shear bond strength of laser groups was not obviously increased, and it was significantly lower than that of air abrasion group. No significant differences of the shear bond strength were found among laser groups treated with different output power or irradiation time. Nd: YAG laser irradiation cannot improve the surface properties of zirconia ceramics and cannot increase the bond strength of the ceramics. Enhancing irradiation power and extending irradiation time cannot induce higher bond strength of the ceramics and may cause material defect.
