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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.

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Abstract Fordyce's Angiokeratoma (AKF) is a benign type of vascular lesion that affects the male and female external genitalia. Prevalence is unknown and there is no apparent hereditary component. Diagnosis can be suggested by ectoscopy, by the presence of purple, bluish, black or red papules on the vulva, clitoris, scrotum, or penis body or glans. Most patients are asymptomatic. Various methods have been used for treatment, including surgery, electrocoagulation, chemical cauterization, sclerotherapy, and LASER. The effectiveness and complications of these therapies are varied. The purpose of this article is to report the case of a 56-year-old woman with abundant and painful vulvar lesions treated with a 1064 nm Nd:YAG LASER. The 1064 nm Nd:YAG LASER proved to be a viable therapeutic option, with satisfactory results and a low rate of complications.

Resumo O angioceratoma de Fordyce é um tipo de lesão vascular de caráter benigno, que compromete as genitálias externas masculina e feminina, cuja prevalência é desconhecida e sem componente hereditário aparente. O diagnóstico pode ser sugerido à ectoscopia pela presença de pápulas púrpuras, azuladas, negras ou vermelhas na vulva, clitóris, escroto, corpo ou glande do pênis. A maioria dos pacientes é assintomática. Vários métodos têm sido utilizados para o tratamento, incluindo cirurgia, eletrocoagulação, cauterização química, escleroterapia e laser. A eficácia e as complicações dessas terapias são variadas. O propósito deste artigo é relatar o caso de uma mulher de 56 anos de idade apresentando lesões vulvares abundantes e dolorosas, tratadas com o laser de pulso longo Nd: YAG de 1.064 nm. O laser Nd: YAG de 1.064 nm apresentou-se como uma opção terapêutica viável, com resultados satisfatórios e baixo índice de complicações.

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Bismuth titanate (BTO) nanoparticles were obtained by pulsed laser ablation in liquid media (PLAL). Distilled water, ethanol, isopropanol, and acetone were used as media for laser ablation experiments, in which the colloidal solutions were obtained. Laser ablation was carried out using the second harmonic and fundamental wavelength of a pulsed Nd:YAG laser (532 nm and 1064 nm, respectively) with laser fluences of 25 and 12 mJ/cm2, respectively. Transmission electron microscopy was utilized for morphological characterization. BTO nanoparticles obtained have spherical shapes with orthorhombic structure and the average size distribution depended on the liquid media nature. In alcohols, BTO NPs were spherical with a carbon layer around them. X-ray diffraction, UV-Vis absorption spectra, and X-ray photoelectron spectroscopy were used to confirm the structural, optical, and elemental properties of the ablated products. The presented results show that PLAL is a viable technique for the synthesis of high-quality BTO nanoparticles with enhanced optical properties for possible applications in photocatalysis.

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A irradiação da dentina com o laser Nd:YAG mostra-se promissora para a qualidade da adesão, desde que aplicada sob parâmetros específicos e em etapas definidas. O objetivo deste estudo é avaliar de forma comparativa, o impacto da irradiação com laser de Nd:YAG sobre a formação e estabilidade da camada híbrida em dentina humana, pré-tratada com ácido e primer de sistema adesivo convencional, "in vitro". Setenta molares hígidos tiveram suas raízes e porções coronárias seccionadas horizontalmente, até completa exposição de dentina oclusal. As amostras foram divididas em: G1 (controle n=20); G2 (experimental n=20), sendo 10 dentes de cada grupo destinados ao microcisalhamento (MC) e 10 dentes à microscopia eletrônica de varredura (MEV). Nos 30 dentes restantes analisou-se: textura por Tomografia Computadorizada de Feixe Cônico (AT=15); e Espectroscopia de Infravermelho por Transformada de Fourier (FTIR=15) em 3 momentos: dentina controle; após tratamento com ácido + primer; e posterior à irradiação a laser. Estatisticamente, optou-se por ANOVA 1 fator, Qui Quadrado de Pearson, teste T e múltiplas comparações de Tukey com significância de 5%. A FTIR evidenciou redução dos níveis de fosfato e carbonato nos momentos primer e após irradiação laser, porém não havendo desnaturação do colágeno exposto. A análise de textura evidenciou uma tendência à formação de um tecido mais padronizado após o uso do laser. O teste de MC evidenciou valores médios de 36,5 e 35,2MPa para G1 e G2 respectivamente (p>0,05) e portanto, de forma imediata, o laser não mostrou efeitos deletérios ao processo adesivo. Além disso, observou-se maior penetrabilidade do adesivo na avaliação em MEV após a aplicação do laser. Novas pesquisas com avaliação longitudinal mostram-se necessárias para verificar se o efeito do laser pode ter sido protetor da degradação hidrolítica, visto que há uma redução do conteúdo de água local durante a formação da camada híbrida (AU).

Irradiation of dentin with the Nd:YAG laser shows promise for the quality of adhesion, as long as it is applied under specific parameters and in defined steps. The objective of this study is to comparatively evaluate the impact of irradiation with Nd:YAG laser on the formation and stability of the hybrid layer in human dentin, pretreated with acid and primer of conventional adhesive system, "in vitro". Seventy healthy molars had their roots and coronal portions horizontally sectioned, until complete exposure of occlusal dentin. The samples were divided into: G1 (control n=20); G2 (experimental n=20), with 10 teeth from each group destined for microshearing (MC) and 10 teeth for scanning electron microscopy (SEM). In the 30 remaining teeth analyzed: texture by Cone Beam Computed Tomography (AT=15); and Fourier Transform Infrared Spectroscopy (FTIR=15) in 3 moments: dentin control; after treatment with acid + primer; and after laser irradiation. Statistically, we opted for 1-way ANOVA, Pearson's Chi Square, T test and Tukey's multiple comparisons with a significance of 5%. FTIR showed a reduction in phosphate and carbonate levels in the primer moments and after laser irradiation, but there was no denaturation of the exposed collagen. The texture analysis evidenced a trend towards the formation of a more expressive tissue after the use of the laser. The CM test showed mean values of 36.5 and 35.2MPa for G1 and G2 respectively (p>0.05) and therefore, immediately, the laser showed no deleterious effects on the adhesive process. In addition, greater penetrability of the adhesive was observed in the SEM evaluation after laser application. New studies with longitudinal evaluation are necessary to verify if the laser effect could have been protected from hydrolytic degradation, since there is a reduction in the local water content during the formation of the hybrid layer (AU).

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Ankyloglossia is considered a congenital patology, whose treatment indicated is a frenectomy, this surgical technique consists in remove the tissue that joins the tongue with the floor mouth. This technique allows the patient a considerable improvement to limitations caused by this anomaly such as difficulties in suction, pronunciation, chewing and difficulty in touching the lower lip with the tip of the tongue. Currently the use of laser technology and its benefits in modern dentistry, allows the realization of surgical procedures free of bleeding, with very little pain and inflammation of the tissues and with a recovery time much lower than necessary with conventional techniques. The present clinical case, show a 12-year-old patient with severe ankyloglossia, lingual frenectomy was indicated. A contact Nd: YAG laser was used, achieving a surgical intervention with little pain, free bleeding and without suture.

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Una de las causas de la disminución de la visión es la catarata. El tratamiento es la extracción del cristalino opaco con reemplazo por un lente intraocular (LIO). La opacidad de cápsula posterior (OCP) es una complicación frecuente a largo plazo. Las modificaciones en el diseño del LIO tanto del material y la forma tienen mayor importancia para prevenir la OCP. Como tratamiento está la capsulotomía neodimio YAG láser. Objetivo: identificar la OCP relacionado con el tipo de LIO implantado en pacientes pseudofáquicos en la FBO, entre el periodo de marzo del 2019 hasta febrero del 2022. Métodos: estudio observacional, tipo analítico, subtipo cohorte histórica, retro- prospectiva y longitudinal, con enfoque de análisis estadístico de tipo cuantitativo. Resultados: predominó el género femenino con un 60 % y un 40 % representaba al masculino; un 60,3 % del total tenían entre 65 a 80 años. La OCP en los 3 tipos de lentes intraoculares (acrílico y PMMA) ocasionó una disminución en la agudeza visual: el 37 %, predominó, por el LIO hidrofóbico, 36 % por el LIO PMMA y destacamos que el 27 % fue por el LIO hidrofílico. La incidencia de OCP a 5 años fue del 32 %. No se registró ningún efecto adverso en nuestro estudio. Conclusiones: la OCP provoca una baja de agudeza visual leve a moderada en los 3 tipos de LIOs; con un mínimo predominio de BAV leve para el tipo de LIO hidrofóbico comparado con el hidrofílico. Además después de la capsulotomía un gran porcentaje tiene entre 20/20 a 20/25 de AV mejor corregida.

One of the causes of decreased vision is cataract. Treatment is removal of the cloudy lens with replacement by an intraocular lens (IOL). Posterior capsule opacity (PCO) is a common long-term complication. Modifications in the design of the IOL both in terms of material and shape are of greater importance in preventing PCO. Treatment is neodymium YAG laser capsulotomy. Objective: to identify the PCO related to the type of IOL implanted in pseudophakic patients in the FBO, from March 2019 to February 2022. Methods: observational study, analytical type, historical cohort subtype, retro-prospective and longitudinal, with a quantitative statistical analysis approach. Results: the female gender predominated with 60% and 41% represented the male; 60.3% of the total was between 65 and 80 years old. PCO in the 3 types of intraocular lenses (acrylic and PMMA) caused a decrease in visual acuity: 37%, predominated, due to the hydrophobic IOL, 36% due to the PMMA IOL and we highlight that 27% was due to the hydrophilic IOL. The incidence of PCO at 5 years was 32%. No adverse effect was recorded in our study. Conclusion: PCO causes mild to moderate visual acuity loss in all 3 types of IOLs; with a minimal predominance of mild AVB for the hydrophobic IOL type compared to the hydrophilic one. In addition, after capsulotomy, a large percentage has between 20/20 and 20/25 better corrected visual acuity.

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OBJECTIVES: To evaluate the effect of Nd:YAG laser irradiation as a prior desensitizing strategy on immediate and medium-term microtensile bond strength (µTBS) to simulated hypersensitive dentin. MATERIALS AND METHODS: Flat mid-coronal dentin was obtained from third molars and submitted to a 600-grit SiC paper (1 min; N: normal dentin) or subsequently challenged with citric acid (6%, 1 min; H: simulated hypersensitive dentin). Afterwards, dentin was or was not (C: control; HC, NC - each n = 7) irradiated with Nd:YAG laser (L: laser; 1.0 W/10 Hz/100 mJ/4 irradiations of 50-60 s; HL, NL - each n = 7). A 2-step self-etch adhesive (Clearfil SE Bond) was applied and composite (Filtek Z350) buildups were constructed. After 24-h (distilled water/37 °C) storage, specimens were sectioned into beams and tested (µTBS; 0.5 mm/min) immediately or after 6-month aging. Three-way ANOVA and Tukey tests were applied (α = 0.05). Qualitative evaluation of the adhesive interface (n = 1 extra tooth per group) was performed by Confocal Laser Scanning Microscopy. RESULTS: Substrate condition (p < 0.001), laser irradiation (p < 0.001), and aging (p = 0.002) influenced the results. Furthermore, there was interaction between substrate and irradiation (p < 0.001). Laser irradiation favored µTBS exclusively to hypersensitive dentin immediately and after aging. µTBS to hypersensitive dentin was higher than that to the normal substrate only when it was laser-irradiated. In any case, immediate µTBS was always higher than that after aging. CLSM revealed longer and more numerous resin tags for simulated hypersensitive dentin, and shorter and fewer resin tags for laser-irradiated dentin. No differences were observed in the hybrid layer itself. CONCLUSION: Nd:YAG laser irradiation prior to restoration favored the µTBS of a self-etch adhesive and resin composite to hypersensitive dentin. CLINICAL RELEVANCE: Desensitizing strategies are usually tried before performing restorative treatments in hypersensitive dentin; therefore, they may influence behavior of the adhesive interface established. However, instead of causing concern, Nd:YAG laser irradiation revealed a favorable effect on the aforementioned interface.

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Introduction: Although tattoos are ancient and very popular among young people, it is also a reason for regret, and many people today have a desire to remove them. Among the possibilities for this, laser removal is the most successful procedure with the highest degree of pigment removal and the lowest risk of complications. Methods: This study was recorded on three patients with tattoos, and only the black pigments were removed. None of the patients involved had a history of skin allergies, skin cancer, and/or keloid formation. Case 1 had a professional tattoo removed in the right calf region in two sessions. Case 2 had an amateur tattoo that was removed on the scalp in three sessions. Finally, Case 3 had two professional tattoos, which were removed from the face in a total of eleven sessions. The following equipment was used: Spectra XT Q-Switched Nd:YAG 1064 nm with a pulse width of 5 ns; Pico Ultra 300 Nd:YAG 1064 nm with a pulse width of 300 ps; and SoftLight Q-Switched Nd:YAG 1064 nm with a pulse width of 17 ns. Results: In general, satisfactory results were obtained, but hypopigmentation was present in Cases 1 and 3. This was probably due to sun exposure at the laser removal site, the short interval between the sessions, and/or higher radiant exposure combined with a smaller spot size, respectively. Conclusion: To achieve a successful tattoo removal in the higher phototypes and reduce unwanted effects, the professionals must know the best parameters to be used, as well as the adequate foundation on the individual characteristics of each patient and the tattoos. Furthermore, patient compliance with the pre/post session care and a suitable interval between the laser sessions are essential to avoid undesirable complications.

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Q-switched 1064 nm/532 nm Nd: YAG Lasers present important characteristics which can contribute toward the removal of tattoos, for having the ability to reach only specific targets with minimal damage to the tissue. Despite reports of their clinical benefits, only a few scientific studies demonstrate the efficacy and safety of these types of lasers in the short and long term. To substantiate the effects, benefits, and safety of the application of Q-switched 1064 nm/532 nm Nd: YAG lasers, a systematic review was carried out from September to December of 2019, about the studies which report their use in the removal of tattoos, published in the last 20 years. Randomized clinical trials in humans were considered, as long as they evaluated the efficacy, safety, and benefits of the application of Q-switched 1064 nm/532 nm Nd: YAG lasers in the removal of black and color tattoos in different skin phototypes. One hundred and twenty-two articles were identified after the titles, abstracts were read, and duplicates were removed; six articles were left, which were included in the research (188 individuals). The Q-switched 1064 nm/532 nm Nd: YAG lasers seem promising in the short term, with minimal adverse effects; however, the efficacy and safety in the long term still present limitations. Consequently, future research is necessary, with better methodological standardization applied and with a follow-up for a longer period of evaluation of possible permanent adverse effects, to determine the standardization and safety of the therapy with the lasers Nd: YAG de 1064 nm/532 nm Q-switched.

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El síndrome de contracción capsular se describe como una reducción progresiva y acelerada del diámetro de la capsulorrexis y del saco capsular tras la extracción extracapsular del cristalino. Se reporta el caso de una paciente femenina, con antecedentes de miopía elevada, a quien se le realizó cirugía de catarata de ambos ojos sin complicaciones transquirúrgicas, y regresa con síndrome de contracción capsular bilateral al mes de operada. Se comenta la conducta seguida en ambos ojos(AU)

Capsule contraction syndrome is described as progressive, accelerated reduction in capsulorhexis and capsular bag diameter after extracapsular crystalline lens extraction. A case is presented of a female patient with a history of high myopia who underwent cataract surgery of both eyes without any intraoperative complication. One month after surgery the patient presents with bilateral capsule contraction syndrome. Comments are made on the clinical management of each eye(AU)

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Case Description: A 16-year-old male patient presented with a 12-days sudden painless loss of vision in his left eye after diving in a lake. Best corrected visual acuity (BCVA) in the left eye was counting fingers. Anterior segment was unremarkable. Fundoscopy in the left eye revealed a pre-retinal hemorrhage in the macular region and swept-source ocular coherence tomography (SS-OCT) confirmed the location in the sub-inner limiting membrane (ILM) space. An Neodymium:YAG (Nd:YAG) laser membranotomy was performed the next day in order to drain the hemorrhage into the vitreous cavity. A couple of days after, the BCVA in the left eye improved to 20/ 25, at fundoscopy the blood being almost reabsorbed and the SS-OCT showing a resolution of the sub-ILM hemorrhage. Discussion: Due to Valsalva retinopathy, sub-ILM hemorrhage may lead to a sudden painless vision loss. Spontaneous resolution of the hemorrhage is possible but absorption may take a long time. During this period, intraretinal tissue migration and proliferation may lead to permanent structural damage. Posterior vitrectomy is a treatment option but the fact that it is an invasive procedure fuels the search for less invasive treatment methods and Nd:YAG laser membranotomy fits this place. Conclusion: Given the excellent results and low complication rates, Nd:YAG laser membranotomy is highly recommended to treat this condition as it offers a simple, relatively safe and a non-invasive treatment option for drainage of sub-ILM hemorrhages.

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BACKGROUND: Vitreous floaters are a common and inconvenient phenomena. This study aims to examine the efficacy and safety in treating vitreous floaters using Nd:YAG laser vitreolysis. METHODS: In this prospective double-blinded randomized clinical trial 24 eyes of twenty-four patients were randomized into intervention with YAG laser vitreolysis and control groups. Primary outcomes were visual disturbance on a 10-point scale, qualitative changes in a 4-level scale, contrast sensitivity measured with the Pelli-Robson table and the National Eye Institute Visual Functioning Questionnaire 25 (NEI VFQ-25). Secondary results included objective change in vitreous opacities, best-corrected visual acuity (BCVA), variation in intraocular pressure (IOP) and other adverse events. RESULTS: Twenty-one patients (21 eyes; 5 male, 16 female) were enrolled in this study (mean age 62 ± 7.9 years), three were lost during follow-up. In the YAG laser group, the 10-point visual disturbance score improved a mean of 4.7 points (p < 0.001) compared to the control group that improved 2.1 (p = 0.09). The YAG laser group reported greater subjectively symptomatic improvement (77%) than controls (25%). NEI VFQ-25 revealed improved general vision (75.8 versus 59.2; p = 0.037) and in mental health at 6 months (84.3 versus 70.3; p = 0.048). There was no significant difference in contrast sensitivity (p = 0.848) and in IOP (p = 0.505). No differences in adverse events between groups were identified. CONCLUSION: Vitreolysis with Nd:YAG laser improves visual results in patients with symptomatic vitreous floaters, without adverse events considered clinically relevant. Other trials with a larger number of participants are required to corroborate these results.

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Background: To present the benefits of high power lasers (Er: YAG and Nd: YAG) over the use of the high speed turbine for the extraction of ceramics restorations, without damaging the surfaces of the teeth; being a relatively easier and faster procedure without the use of anesthetic agents, and the preparation of the ceramic restorations and cementing in the single session; with a follow-up of 1 year. Objective: The benefits of lasers over high-speed turbine mechanical instrumentation for crown removal encompass efficient restoration recovery without damage to tooth surfaces; and a relatively easier and faster procedure without the use of anesthetic agents. Methods: The Er: YAG laser (no contact; 3.2-4.0 W, 20 Hz) was used to extract the porcelain prosthesis, followed by a gingivectomy with the Nd: YAG laser on tooth 12 to improve the gingival contour. The dental surfaces where the ceramic prosthesis will be cemented were scanned. Then, CAD / CAM technology was used to make the ceramic veneers that were cemented in the same session. Results: The efficacy the Er:YAG laser energy was observed by the decreased of the time to remove all-ceramic materials through ablation of bonding cements, reducing working time by 75% compared to a high-speed turbine. Conclusions: An Er: YAG laser can safely remove lithium disilicate crowns with the settings used in this study. Laser-assisted removal of all ceramic PDFs is a promising treatment protocol. The use of the Nd: YAG (2.0 W power, short 20Hz, 320 µm optical fiber, in contact) laser allowed gingivoplasty to be performed, automatically cauterizing avoiding post-operative bleeding, and facilitating the preparation of ceramic restorations the same day. The use of high-power lasers and the use of accompanying CAD / CAM technology allowed this clinical case to be completed in a single visit without the use of temporary restorations, achieving absolute patient satisfaction. (AU)

Antecedentes: Apresentar os benefícios dos lasers de alta potência (Er: YAG e Nd:YAG) sobre o uso da turbina de alta velocidade para a remoção de restaurações cerâmicas, sem danificar as superfícies dos dentes; sendo um procedimento relativamente mais fácil e rápido evitando o uso de agentes anestésicos, conseguindo fazer o preparo das restaurações de cerâmica e cimentação em uma única sessão; com seguimento de 1 ano. Objetivo: Os benefícios dos lasers sobre a instrumentação mecânica com turbina de alta velocidade para a remoção da coroa abrangem a recuperação eficiente da restauração sem danos às superfícies dos dentes; e um procedimento relativamente mais fácil e rápido sem o uso de agentes anestésicos. Métodos: O laser Er: YAG (sem contato; 3,2-4,0 W, 20 Hz) foi utilizado para remover a prótese de porcelana, seguido de gengivectomia com o laser Nd: YAG no dente 12 para melhorar o contorno gengival. As superfícies dentais onde a prótese de cerâmica será cimentada foram escaneadas. Em seguida, a tecnologia CAD / CAM foi utilizada para confeccionar as facetas de cerâmicas que foram cimentadas na mesma sessão. Resultados: A eficácia da energia do laser Er: YAG foi observada pela diminuição do tempo na remoção dos materiais cerâmicos por meio da ablação dos cimentos de ligação, reduzindo o tempo de trabalho em 75% em relação a uma turbina de alta velocidade. Conclusão: Um laser Er: YAG pode remover com segurança as coroas de dissilicato de lítio com as configurações usadas neste estudo. A remoção assistida por laser de todos os PDFs de cerâmica é um protocolo de tratamento promissor. O uso do laser Nd: YAG (2,0 W potência, curta 20Hz, 320 µm fibra ótica, em contato) permitiu a realização da gengivoplastia, cauterizando automaticamente evitando sangramento pós-operatório e facilitando o preparo das restaurações cerâmicas no mesmo dia. O uso de lasers de alta potência e o uso da tecnologia CAD / CAM que o acompanha permitiram que este caso clínico fosse concluído em uma única visita, sem o uso de restaurações temporárias, alcançando a satisfação absoluta do paciente (AU)

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OBJECTIVES: The present study examined a technique for reducing dentin permeability through the application of a calcium phosphate (CaP)-based desensitiser with a laser-assisted process and evaluated adhesive-dentin bond strength. Methods: Thirty dentin discs were divided into two groups according to whether the selected desensitiser (TeethMate; Kuraray Noritake) was used prior to dentin bonding. Each group was subdivided into three subgroups (n = 5): A- Adhesive (Single Bond Universal, 3M ESPE), AL- Adhesive + Laser (Nd:YAG 60 mJ) and LAL- Laser + Adhesive + Laser. Dentin permeability values (%) were recorded before and after desensitiser application. Resin composites were placed over the bonded specimens; the latter were aged prior to microtensile bond strength evaluation. Gelatinolytic activity within the hybrid layers was examined with in-situ zymography using confocal laser scanning microscopy. Data were analysed with ANOVA and Tukey test (α = 0.05). RESULTS: Significant differences in dentin permeability were identified for all groups (p = 0.00). Both laser treatment (p = 0.182) and desensitiser application (p = 0.687) did not significantly improve dentin bond strength. Ultrastructure of the resin-dentin interface identified presence of calcium phosphate within dentinal tubules. Laser treatment did not affect hybrid layer ultrastructure. Both treatment modalities (intratubular CaP occlusion and laser) had no influence on gelatinolytic activity within hybrid layers. CONCLUSION: Although intratubular CaP occlusion and laser treatment were effective in reducing dentin permeability, they did not affect bond strength, interfacial ultrastructure and gelatinolytic activity within hybrid layers. CLINICAL RELEVANCE: Treatment of etched dentin with Nd:YAG Laser at 60 mJ does not adversely affect collagen ultrastructure and gelatinolytic activity within the hybrid layer. The application of a calcium phosphate-based desensitiser to etch dentin does not affect dentin bond strength.

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Using light sources in phototherapy has presented promising results regarding several types of facial and body skin affections for centuries. The neodymium-doped yttrium aluminum garnet (ND:YAG) 1064 nm laser has become a standard treatment in dermatology for dermatological disturbances related to the pilous follicle and the structures surrounding it. Despite the reports of its clinical benefits, few scientific studies show its actual safety and efficacy. To substantiate the effects, benefits, and safety of applying an ND:YAG 1064 laser in the epilation process during esthetic treatment, a systematic review was carried out between October 2018 and January 2019, on studies published in the last 20 years. Randomized clinical trials in humans were considered that evaluated the efficacy, safety, and benefits of ND:YAG laser application at 1064 nm wavelengths for hair removal. A total of 198 articles were identified; 58 articles remained after their titles and abstracts were read; and 21 articles were selected after the removal of duplicates. After the integral reading, 13 of these articles were included in the systematic review (734 patients). The ND:YAG 1064 nm laser presents safety and promising, beneficial effects in epilation. However, further scientific studies with better methodologic quality are necessary to better standardize ND:YAG laser therapy and clarify its parameters for photoepilation.

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This in vitro study aimed to analyze the physical and chemical characteristics of the hypersensitive human dentin-like surface after application of a bioactive glass (BG) paste (BG/Ac) irradiated or not with high-power lasers. Dentin specimens were treated with 17% Ethylenediamine tetraacetic acid (EDTA) solution to mimic a hypersensitive dentin and then submitted to neodymium: yttrium-aluminum-garnet (Nd:YAG) laser or CO2 laser irradiation prior and after application of BG/Ac. Characterizations were performed by using X-ray diffraction, Fourier transformed infrared spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The results suggested that application of BG/Ac by itself caused some obstructions of dentinal tubules. Nd:YAG laser irradiation reduced the opening of the dentinal tubules with no changes in the collagen structure. CO2 laser irradiation caused dentin melting and resolidification along with cracks and chemical changes in collagen fibers. However, when BG/Ac paste was irradiated with lasers, a sequence of surface reactions between glass and dentin interface led to the formation of an amorphous hydroxyapatite layer, similar to that of an inorganic component of the normal dentin. Moreover, BG/Ac was able to prevent the formation of cracks and degradation of collagen fibers caused by CO2 irradiation. Overall, this study supports that application of BG/Ac paste irradiated by high-power laser could represent an effective and long-lasting therapeutic approach for dentin hypersensitivity.

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Objective: Evaluate the microtensile bond strength (µTBS) in different dentin thicknesses, under simulated pulpal pressure (SPP), submitted to an adhesive technique using laser irradiation. Material and methods: Forty sound human molars were sectioned and randomly divided into two groups (n=20): Group 1 ­ 1 mm of dentin thickness; Group 2 ­ 2 mm of dentin thickness. Each group was divided into two subgroups (n=10): Subgroup A ­ Absence of SPP; Subgroup P ­ Presence of SPP (15 cm H2 O). The samples were sequentially treated with: 37% phosphoric acid, adhesive system (Adper Single Bond 2), Nd:YAG laser irradiation (60 s, 1064 nm, 10 Hz) using 60 and 100 mJ/pulse energy parameters and photopolymerization (10 s). A composite resin block (Filtek Z350) was built up onto the irradiated area. After 30 days stored in water, the samples were sectioned and submitted to microtensile test (10 kgf load cell, 0.5mm/min). Data were analyzed by twoway ANOVA and Tukey tests. Results: Two-way ANOVA revealed no significant differences for SPP on bond strength. The laser energy parameters indicated that 100 mJ showed greater µTBS means compared to the group irradiated with 60 mJ. The presence of SPP reduced the mean µTBS values. Conclusions: Simulated pulpal pressure did not affect the µTBS using 60 mJ of laser energy parameter. At 100 mJ, the presence of SPP negatively influenced the bond strength, regardless of dentin thickness (AU)

Objetivo: O objetivo deste estudo foi avaliar a resistência adesiva (RA) em diferentes espessuras de dentina, associada à pressão pulpar simulada (PPS), quando submetidos à técnica adesiva por irradiação laser. Material e Métodos: Quarenta molares humanos hígidos foram seccionados e divididos aleatoriamente em dois grupos (n=20): Grupo 1 ­ 1 mm de espessura de dentina; Grupo 2 ­ 2 mm de espessura de dentina. As amostras foram divididas em 2 subgrupos (n=10): Subgrupo A ­ ausência de PPS; Subgrupo P ­ presença de PPS (15 cm de H2 O). As amostras foram tratadas seqüencialmente com: ácido fosfórico 37%, sistema adesivo (Adper Single Bond 2), irradiação com Nd:YAG laser (60 s, 1064 nm, 10 Hz) nos parâmetros de energia de 60 e 100 mJ/pulso e fotopolimerização (10 s). Um bloco de resina composta (Filtek Z350, 3M ESPE) foi confeccionado sobre a área irradiada. Após 30 dias armazenados em água, os espécimes foram seccionados e submetidos ao teste de microtração (carga de 10 kgf, 0.5mm/min). Os dados foram analisados pelos testes ANOVA sob 2 fatores e Tukey (p<0.05). Resultados: ANOVA mostrou que não houve diferenças significativas para PPS na RA. Para os parâmetros de energia do laser, 100 mJ apresentou maiores médias de RA quando comparado ao grupo irradiado à 60 mJ. A presença da PPS reduziu as médias de RA. Conclusão: Pressão pulpar simulada não afetou os valores de resistência adesiva para o grupo irradiado com 60 mJ. Para 100 mJ, a presença da pressão pulpar influenciou negativamente na resistência adesiva, independente das espessuras de dentina.(AU)

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Duplex stainless steels (DSSs), a particular category of stainless steels, are employed in all kinds of industrial applications where excellent corrosion resistance and high strength are necessary. These good properties are provided by their biphasic microstructure, consisting of ferrite and austenite in almost equal volume fractions of phases. In the present work, Nd: YAG pulsed laser dissimilar welding of UNS S32750 super duplex stainless steel (SDSS) with 316L austenitic stainless steel (ASS), with different heat inputs, was investigated. The results showed that the fusion zone microstructure observed consisted of a ferrite matrix with grain boundary austenite (GBA), Widmanstätten austenite (WA) and intragranular austenite (IA), with the same proportion of ferrite and austenite phases. Changes in the heat input (between 45, 90 and 120 J/mm) did not significantly affect the ferrite/austenite phase balance and the microhardness in the fusion zone.

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Massive hyphaema presentation after a laser iridotomy is very rare. We report a 63-year-old man with ischaemic heart disease on dual antiplatelet therapy (aspirin plus ticagrelor) who was diagnosed as a primary angle-closure suspect and was to undergo a neodymium-doped yttrium aluminium garnet laser iridotomy at Centro Oftalmológico Virgilio Galvis, Floridablanca, Colombia in 2016. While performing the iridotomy in the left eye, active bleeding occurred that finally filled approximately 75% of the anterior chamber. Intraocular pressure (IOP) increased to 62 mmHg. Mannitol and a topical dorzolamide/timolol were used to control the increase in IOP. The hyphaema slowly resolved over the following week without sequelae. This case revealed that massive hyphaema can complicate laser iridotomy in patients on dual antiplatelet therapy, although this is rare. Therefore, if patients are taking aspirin and ticagrelor, it would be advisable to stop the second medication if possible. In addition, sequential application of photocoagulation and photodisruption lasers might diminish the risk of significant bleeding.

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Objective: The aim of this article was to describe and discuss a clinical case in which the Nd:YAG laser and a desensitizing agent were associated in a protocol for dentin hypersensitivity (DH) in teeth with molar-incisor hypomineralization (MIH). Background data: DH is a common condition among the population, being one of the main reasons for patients to seek for a dental treatment. MIH can be considered a condition that induces DH. Methods: The patient was referred for evaluation, complaining of hypersensitivity during eating or drinking cold foods. Clinical evaluation revealed the presence of MIH on the first lower molars. Aiming to treat DH, two strategies for dentin desensitization were associated: the use of a high-power laser (Nd:YAG laser, 1.064 nm; Lares Research), with a 300 µm quartz optical fiber, 1 W of power, 100 mJ of energy, 10 Hz of repetition rate, and 85 J/cm2 of energy density, followed by the application of two layers of a desensitizing agent (Gluma Desensitizer). Results: DH was evaluated immediately, after 1 week and after 1 month of the treatment. Clinical outcomes were satisfactory, confirming the efficacy and considerable durability of the protocol used for the reduction of DH originated from MIH. Conclusions: The association of Nd:YAG laser and a desensitizing agent for controlling DH was effective, showing to be an interesting protocol.

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