Comparación entre facoemulsificación asistida con femtoláser y facoemulsificación convencional: resultados visuales y complicaciones / Comparison between femtosecond laser-assisted phacoemulsification and conventional emulsification: visual results and complications

La aplicación del femtoláser en la cirugía de catarata podría ser una de las grandes revoluciones contemporáneas ocurridas en el campo del tratamiento de la catarata. Si el uso de esta tecnología provocara una eficacia y seguridad muy superiores sobre la facoemulsificación convencional, justificaría el alto costo que genera para la cirugía de catarata en la actualidad. En revisiones de estudios comparativos no se han encontrado diferencias significativas entre los resultados visuales de ambos procedimientos al final del período de seguimiento posoperatorio. Una mejor circularidad de la capsulorrexis, unido a disminución en la emisión de energía ultrasónica y del tiempo efectivo de faco, son atribuidos como las grandes ventajas del uso del femtoláser en la facoemulsificación. Sin embargo, en cuanto a la pérdida de células endoteliales, el edema corneal posoperatorio y el edema macular posquirúrgico no se han registrado grandes diferencias entre ambas técnicas quirúrgicas, mientras que el costo de la cirugía se incrementa considerablemente con la utilización del femtoláser. Por tanto, se necesitan estudios de gran tamaño de muestra bien diseñados que proporcionen evidencias más fiables respecto al uso del femtoláser en la cirugía de catarata actual(AU)

The application of femtoláser in cataract surgery could be one of the great contemporary revolutions occurred in the field of treatment of cataract. If the use of this technology would cause a very superior efficacy and safety over conventional phacoemulsification, it justifies the high cost it generates for cataract surgery today. In reviews of comparative studies we have not found significant differences between the visual results of both procedures at the end of the period of postoperative follow-up. Better circularity of the capsulorhexis, coupled with decrease in the emission of ultrasonic energy and effective phacoemulsification time, are attributed as the major advantages of using femtoláser in phacoemulsification. However in terms of endothelial cell loss, postoperative corneal edema and macular edema after surgery they have not been recorded big differences between the two surgical techniques, while the cost of surgery is considerably increased with the use of femtoláser. Therefore studies of large sample size, well-designed to provide more reliable evidence regarding the use of femtoláser in current cataract surgery are needed(AU)

Vantagens da frenectomia labial por laser de diodo de alta intensidade / Advantages of lip frenectomy with high-intensity diode laser ­ a case report

Existem condições clínicas em Periodontia na qual o freio labial está posicionado de forma penetrante nas papilas gengivais, ficando muito próximo à margem gengival, podendo predispor ao desenvolvimento de recessões gengivais. Também pode ocorrer dificuldade de higienização, infl amação persistente, restrição no movimento labial, interferência fonética e agravos estéticos, além de dificultar o fechamento de diastemas. Muitas vezes, é indicada a remoção cirúrgica de freios labiais utilizando lâminas de bisturi e, mais recentemente, o laser de alta intensidade. O laser, ao ser absorvido pelos tecidos, gera a vaporização e sublimação, resultando em corte e exérese, além de atuar como auxiliar na cicatrização, provavelmente através da bioestimulação. Seu meio ativo promove a vaporização completa e a coagulação nos tecidos, sem gerar propagação do aquecimento. Há maior controle da hemorragia transoperatória, resultando em um procedimento cirúrgico limpo, frequentemente dispensando suturas, facilitando a visibilidade, execução e remoção do freio labial. O objetivo deste trabalho foi demonstrar as vantagens do laser cirúrgico de alta intensidade (Nd:YAG; 808 nm; 1,2 W; 20 pps; 126 J) a partir de um relato de caso clínico de frenectomia realizada em uma paciente do sexo feminino, com 34 anos de idade, que apresenta freio labial persistente associado a diastema interincisal superior. O procedimento cirúrgico com laser de alta intensidade em tecidos moles apresentou algumas vantagens, como a redução do tempo cirúrgico, de morbidade e sintomatologia pós-operatórias.

There are clinical conditions in periodontics where the labia frenulum is deeply positioned into the gingival papillae getting very close to the gingival margins, predisposing the development of recessions, causing difficulties for cleaning, with persistent infl ammation, lip movement restrictions, phonetic interference, esthetic alteration, besides preventing diastema closure. Oftentimes, removal with a surgical blade or high-intensity lasers is recommended. The laser is absorbed by the tissues generating vaporization and sublimation which results in cutting and excision, and increased improved healing possibly due to its bio-stimulatory effect. Its active medium promotes complete tissue vaporization and coagulation, without heat propagation, control of the intraoperative bleeding and a clean surgery that often does not require sutures. This facilitates visibility, execution and removal of the labial frenulum. The aim of this paper was to demonstrate the surgical benefi ts of the high-intensity laser (Nd:YAG; 808 nm; 1.2 W; 20 pps; 126 J) in a case report of frenectomy for a 34 years-old female patient presenting persistent inter-incisal diastema associated with an atypical labial frenulum. The soft tissue laser therapy has the advantage of reduced clinical time and still not promoting edema, with minimal postoperative pain and side effects.

A influência do laser de baixa intensidade na osseointegração de implantes de titânio ­ revisão sistemática / The influence of low-level laser therapy (LLLT) on the osseointegration of titanium implants ­ a systematic review

Objetivo: fazer uma revisão da literatura sobre o laser de baixa intensidade (LLLT) e seus efeitos na osseointegração dos implantes de titânio. Material e métodos: uma busca eletrônica foi realizada nos bancos de dados PubMed/Medline e Cochrane Library, entre 1995 e 2015, limitando-se aos artigos em inglês e usando as seguintes palavras-chave: "LLLT", "dental implant" e "osseointegration", combinadas por operadores booleanos. Resultados: das 96 referências analisadas inicialmente, apenas 17 artigos foram incluídos (15 estudos em animais, dois estudos em humanos). Quinze artigos mostraram efeitos positivos da LLLT, enquanto dois foram neutros. Houve grande variabilidade no uso da LLLT, sobretudo no que se refere à dose utilizada, ao número de sessões, à energia de irradiação, e ao comprimento de onda. Conclusão: mais pesquisas sobre este tema são necessárias, utilizando doses padronizadas, assim como comprimento de onda e protocolos de aplicação pré-definidos.

Objective: to perform a systematic review on low-level laser therapy (LLLT) and its effects on the osseointegration of titanium implants. Material and methods: an electronic search was on the PubMed/Medline database and Cochrane Library between 1995 e 2015, restricted to the English literature and using the keywords: "LLLT", "dental implant", and "osseointegration" combined by Boolean operators. Results: from the 96 initially retrieved references, only 17 articles were included (15 animal studies, 2 human studies). Fifteen articles showed positive effects, while only two demonstrated neutral effects of LLLT. A great variability was found on LLLT regarding doses, number of sessions, energy, and wavelengths used. Conclusion: further research on this topic need to be made using standard doses, wavelengths, and pre-defi ned application protocols.

Dry eye syndrome after laser in situ keratomileusis [LASIK] for correction of myopia

To evaluate the incidence of dry eye syndrome after laser in situ keratomileusis [LASIK] and to determine the pattern of tears recovery. In a prospective, non comparative case study, 33 eyes [20] patients underwent laser in situ keratomileusis to correct myopia ranging from -0.75 to -14.00D. Each eye was followed for mean period of 12 months [10 - 14 months]. Patients were followed at 2 weeks and 2 days preoperatively and 1 day, 1 and 2 weeks, 1, 3, 6, 9 and 12 months postoperatively, measuring the Snellen visual acuity, corneal sensitivity, corneal fluorescein staining, tear break-up time, basic aqueous tear production by the Anaesthetized Schirmer test, and corneal Surface Regularity Index [SFU]. Patients were divided according to the depth of ablation into group A [ablation depth < 100 microm and group B [ablation depth >100 microm] dry eye syndrome after laser in situ keratomileusis was evident at the ablated zone during the first 3 months after surgery and only at the 6th months it returned to its preoperative values. Recovery was more rapid at the hinge than the other points. The degree of sensation loss appears to correlate with the ablation depth and degree of dry eye symptoms. The results suggest that lamellar cutting of the cornea during LASIK impairs corneal sensitivity and modifies tear production and the depth of the corneal ablation affects the extent of dryness and recovery

Interaction model of laser radiation and structures of the eye-fundus

For some time past lasers have been used in ophthalmology more and more wide, i.e. for microsurgical interventions to structures of eye-fundus. Concurrently with application of lasers there develop theories aimed at explanation of what is the mechanism of action of the laser radi-ation on eye-fundus. Thermal mechanism of visual organ damage by a light beam is the most universal one for visible and infra-red subspectrum [15]. Vos J.J. was the first who tried to create a theory of retinal burns on the basis of experimental data of Ham W.T. It was suggested that the radiation absorbs uniformly in a parallelepiped with thickness 10 ¥um and radiation spot 130 urn with radiation time over 20 ms. Distribution of temperature studied by VOS J.J. with the help of heat-transfer equation showed that thermal effects shall occur at extremely high temperature [over 100° C], though the data did not confirm existence of boiling and steam production in eye tissue under the corresponding conditions[16,8]. One of the first studies concerning temperature measurement in the course of laser coagulation were experiments of Campbell C.J. There was measured the temperature at different distances from the radiation point of retina irradiated by a milli second pulso of a ruby laser. It was defined that in the area of coagulation the temperature increased at 30° C, however at the distance of 1 mm from the coagulation point the temperature increase was not higher than 1° C [5]. A more perfect model of the heating of eye-fundus tissues was developed by Ham W.T. and Clark A.M. It was suggested in the model that pigment epithelium and choroids are uniform absorbers with different absorption factors. Thermal performance has been accepted equal to thermal performance of water. On examination of these models it was defined that in some time after beginning of radiation there establishes a stable temperature, and the speed of its stabilization and its value depend on diameter of a radiation spot[6,7,8]. Subsequently there have been offered some more models of thermal damage of eye tissues taking into account spectral dependence of temperature effects of eye-fundus tissues ra-diation heating, granularity of light-absorbing layers and duration of exposure[4,10,12,14,18]. A number of authors calculate the increase of temperature inside of radiated retinal vessels taking into account their cooling due to blood flow [3]. The most exact temperature prediction 1% inside retina was provided by Wheeler [17]. The model developed by Wheeler suggests exponential absorption within two layers: melanin layer in pigment epithelium with thickness of 4 microm and vascular layer 30 urn thick. Distance between layers' centers is 30 microm, It is assumed that both layers have equal heat and temperature transfer. For forecast of eye-fundus tissues damage by light radiation there have been developed models taking into account character of distribution of light energy in a beam formed by this optical system and absorption characteristics of radiated biological tissue [1,2,3,13].However there is no model of selective action of laser energy on eye-fundus structures. Purpose of our study was development of interaction model of laser radiation and retina tissues. Commencing development of interaction model of laser radiation and eye-fundus structures we suggest that as diameter of laser ray is much lower than eye-fundus flexion it may be deemed flat. One can neglect absorption of laser radiation in cornea!, lens and sclera since it is relatively small comparing to absorption in pig-ment-epithelial layer [PEL] and chorioid. Let us examine effects of biological impact in case of single and series of pulses separately. Laser emits a single pulse with energy EO. At the same time it is not important how this pulse has been obtained: by overlap of continuous radiation or by periodical generation

Laser em dermatologia: princípios físicos, tipos e indicaçöes / Laser in dermatology: phisycal principles, types and indications

O uso de laser em dermatologia tem se expandido muito nos últimos anos. O avanço tecnológico, em mais de 30 anos, permite que a eficácia e as respostas terapêuticas sejam cada vez melhores. Porém, mais complexos tornam-se a compreensäo do seu uso e suas indicaçöes em dermatologia

Aplicación de la nefelometría laser en inmunología y microbiología / Laser nefelometry immunology and microbiology

Objetivo: evaluar la utilidad de la nefelometría láser en los estudios inmunológicos y microbiológicos. Material y métodos: se realizaron cuantificaciones de diversas proteínas plasmáticas: IgG, IgA, IgM, C3 y C4 por nefelometría laser utilizando como controles los estándares proporcionados por una casa comercial. Para su análisis los datos se transformaron a escalas logarítmicas y se calcularon ecuaciones de regresión lineal. Para la evaluación microbiológica se realizaron concentraciones bacterianas decimales hasta 10 a la 6 de E. coli en caldo de Hinto-Muller. Todas las concentraciones se leyeron cada 5 o 10 minuto durante 70 minutos para determinar la cinética de crecimiento. También se midió inhibición de amikacina sobre E. coli. Resultados: las ecuaciones calculadas empíricamente mostraron una buena reproducibilidad y una vigencia aproximada de seis meses para las proteínas plasmáticas. Así mismo la nefelometría mostró que permite realizar un cálculo rápido de la concentración mínima inhibitoria de crecimiento bacteriano

Tratamiento de la patología vascular superficial con el laser SPTL-1A / Treatment of superficial cutaneous vascular lesions with SPTL-1 laser

El laser SPTL-1 es un laser colorante pulsado creado específicamente para el tratamiento por fototermolisis selectiva de lesiones vasculares superficiales, como angiomas planos y telangioectasias faciales. Con este laser es posible el tratamiento en edades tempranas, al eliminar el riesgo de quemaduras y cicatrices hipertróficas, relativamente frecuentes con los láseres de argón y CO2

Irradiaçäo da medula espinhal com laser de arseneto de galio em ratos: aspectos anatomopatologico / Spinal cord irradiation with GaAs laser in rats: anatomopathologic study

Foram estudados os efeitos do laser sobre a medula espinhal de ratos.Os animais do G-1(10)constitiiram o grupo-controle;os do G-ll(10)receberam 9,15 j/cm por 30 seg em seis pontos durante dez dias,sendo sacrificados logo apos a ultima sessao;os do G-lll(10),9,15 j/cm por 30 seg em seis pontos durante dez dias e sacrificados apos 20 dias;os do G-lV(10),18,30 j/cm por 60 seg em seis pontos durante dez dias e sacrificados logo apos a ultima sessao;os do G-V(10)18,30 J//cm por 60 seg em seis pontos durante dez dias e sacrificados apos 20 dias.Nao houve alteracoes anatomopatologicas a microscopia optica.

El laser de CO2 en dermatología / CO2 laser in dermatology

Presentamos 74 pacientes con diferentes patologías que fueron tratadas con laser de CO2. Describimos la técnica usada en cada patología. los resultados y evolución

new method for location of a difficult-to-find root canal orifices: an in-vitro study

In this study, Nd: YAG laser was used as an aid to facilitate the detection of the difficult-to-find orifices of the main and extra root canals. Eighty human extracted teeth were used. The teeth were divided into two groups, forty teeth each. In group I, access cavities according to Black's principles were prepared. In group II, cervical cross-sections were performed. Using Nd: YAG laser at power 15 pps/1.5 w for 1/2-1 minute, applying it to the access cavities and the prepared cervical cross-sections, resulted in black dicoloration and accentuation of the most of the existing main and extra orifices of the root canals. The dark black discoloration might result from carbonization of the organic contents of the canals. This laser effect facilitated the detection of the difficult-to-find orifices and the identification of most of the orifices of the extra canals

Effects of ND: YAG laser on the apical seal of three different retrograde filling materials

Sixty human single rooted m and ibular premolars with single apical foramen were used in this study. The crowns of the selected teeth were capitated. The root canals were obturated with single cone gutta percha technique and the apical cavities were performed to approximately 2 mm deep. The prepared roots were divided into two main groups, the apical cavities of the first group were exposed to Nd: YAG laser [1.06 wave length, 1.6 w, 15 pps] for 1.5 minutes, while the second group left without laser exposure. Each main group was subdivided into three subgroups according to the retrofilling material used. The roots were retrofilled with amalgam in subgroup A [control group], glass ionomer [Ketac Endo] in subgroup B and ultrafil in subgroup C. After coating the root surface with nail polish except the apical cavity, the roots were placed in Indian ink for 7 days. Longitudinal sections were prepared and the amount of dye penetration was measured. When laser was used, amalgam had significant lowest mean leakage [1.88] versus glass ionomer and ultrafil. Also, there was statistically significant reduction of the mean leakage of lased amalgam versus unlased

Comparison of dentinal wall adaptation of Ultrafill versus lateral and vertical condensation techniques after pre-treatment ND-YAG laser A scanning electron microscopic study

Sixty extracted single rooted m and ibular premolars were decapitated and biomechanically instrumented 1 mm shorter to the apex to the size 40 K-file. Step back instrumentation technique was done up to size 70 k-file. The coronal portion of each root canal was further flared with Gate Glidden bur 1 and 2. The prepared roots were divided into two main groups. The root canal walls in the first group were exposed to Nd-YAG laser [1.06 wave length] at energy of 15 pps and 1.5 w for 1.5 minutes; while in the second group, they were left without laser exposure. According to root canal filling technique, each group was subdivided into three subgroups, each contained ten root canals. The root canals were obturated using lateral condensation technique in the first subgroup, vertical condensation technique in the second subgroup, while the low temperature injected thermoplasticized gutta percha was used in the third subgroup. By scanning electron microscope, it was observed that the laterally condensed and injected thermoplasticized gutta percha had poor adaptation to the unlased dentin wall, while insignificant versus vertical condensation technique. In the dentin lased group, although there was no significant difference among the three filling techniques, the laterally condensed and injected thermoplasticized gutta percha were significantly better in adaptation to the lased dentin versus unlased dentin