LUCIANO BACHMANN
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Resumo IPEN-doc 09172 Effects of the diode laser irradiation on root surfaces2004 - HAYPEK, P.; THEODORO, L.H.; BACHMANN, L.; EDUARDO, C.P.; SAMPAIO, J.E.C.; ZEZELL, D.M.The purpose of this study was to evaluate the temperature rising inside the pulpar cavity during the diode laser irradiation on the root surface. Twelve single root teeth were used and their mesial and distal surfaces were irradiated (808 nm, 400 m, 30 s), in a continuous mode (CW) and in an switched mode (SW) (10 Hz). The temperature rise was evaluated deppending with the power used (0.4 W to 2.2 W). The temperature was monitorated with a termopar (T) fixed inside de pulpar cavity during the irradiation. In a second step two parameters was used in a SW (10 Hz). The safety temperature was keep using the power: Group A - 0.9 W (mesial ) and Group B - 1.08 W (distal). The results showed the termal pulpar events (T) during the irradiation, based in an specific relation with the power (P), like T= -0.4+3.7P in a CW and T= -0.2+2P in a SW. The temperature rising during the irradiation was 3.4±0.4ºC on Group A and 4.0±1.0ºC on Group B. The irradiation mode and the power are much important to temperature rise inside the pulpar cavity and the 0.9 W and 1.08 W radiation on the root surfaces were safety.Resumo IPEN-doc 08431 Chemical Modification of bovine dental enamel irradiated with holmiun laser2004 - EDUARDO, P.L.P.; BACHMANN, L.; SALVADOR, V.L.; ZEZELL, D.M.This study investigated Ho:YLF (2,065 mm) effects on dental enamel with regards to the thermal variations in the pulp chamber during irradiation and resistance to demineralization. Twenty samples of bovine enamel were divided: 1) control- acidulated phosphate fluoride (APF) topic application followed by demineralization treatment with lactic acid; 2) Ho:YLF irradiation (100J/cm2) followed by APF and demineralization; 3) Ho:YLF irradiation (350J/cm2) followed by APF and demineralization; 4) Ho:YLF irradiation (450J/cm2) followed by APF and demineralization. All samples were quantified according to their calcium and phosphorous atoms relative concentrations before and after the treatments. X-Ray fluorescence spectrochemical analysis showed an increase on the calcium and phosphorous atoms concentration ratio and therefore the enamel demineralization reduction as a result of the lactic acid treatment in the samples irradiated with the holmium laser followed by the APF (ANOVA, Tukey p<0,01). To evaluate the feasibility of this study for clinical purposes, surfaces morphology were analyzed. Modifications were characterized by melted and re-solidified regions of the enamel, which can changes its permeability and solubility. Temperature changes of ten human pre-molars teeth irradiated with 350 J/cm2 and 450 J/cm2 were also monitored in the pulp chamber in real time. Temperature increases were limited to 4,2° C.Resumo IPEN-doc 01816 Effect of Er:YAG and diode lasers in the adhesion of blood components and in the morphology of irradiated root surfaces2004 - THEODORO, L.H.; GARCIA, V.G.; ZEZELL, D.M.; HAYPEK, P.; BACHMANN, L.; SAMPAIO, J.E.C.The aim of this study was to evaluate in vitro the adhesion of blood components on root surfaces irradiated with Er:YAG (2.94??m) and GaAlAs Diode (808 nm) lasers and these effects on irradiated root surfaces. It was obtained 100 samples of human teeth. They were scaled and divided into five groups of 20 samples each: G1 (Control); G2 -Er:YAG laser (7.6 J/cm2); G3 - Er:YAG laser (12.9 J/cm2); G4 -Diode laser (90 J/cm2) and G5 - Diode laser (108 J/cm2). After these treatments were conducted, 10 samples of each group received a blood tissue, and the reminiscent 10 samples did not receive such treatment. After laboratorial treatments the samples were analysed by scanning electron microscopy. The results have shown that there were no significant differences between the Control Group and the groups treated with Er:YAG laser (p=0,9633 and 0,6229); G4 and G5 were less effective than the Control Group and the Er:YAG laser groups (p<0,01). No proposed treatment increased the adhesion of blood components in a significant way when compared to the Control Group; although the Er:YAG laser did not interfere in the adhesion of blood components it caused more changes on the root surface, while the Diode laser inhibited the adhesion.Resumo IPEN-doc 01531 Changes in chemical composition and collagen structure of dentin tissue after erbium laser irradiation2004 - BACHMANN, L.; DIEBOLDER, R.; HIBST, R.; ZEZELL, D.M.The erbium laser light has a great affinity to the water molecule, which is present in great quantity in biological hard tissues. The objective of this work is to identify chemical changes by infrared spectroscopy of irradiated dentin by an Er:YAG - 2.94μm laser. The irradiation was performed with fluences between 0.365 J/cm2 and 1.94 J/cm2. For the infrared analysis a Fourier transform infrared spectrometer was used. After the irradiation were observed: loss of water, alteration of the structure and composition of the collagen and increase of the OH- radical. These alterations can be identified by a decrease of the water and OH- band between 3800-2800 cm-1, bands ascribed to collagen structure between 1400-1100 cm-1. The results show that the erbium laser changes the structure and composition of the organic matrix, OHradical and the water composition in the irradiated dentin.Livro IPEN-doc 11291 Estrutura e composição do esmalte e da dentina: Irradiação laser e tratamento térmico2005 - BACHMANN, LUCIANO; ZEZELL, DENISE M.Resumo IPEN-doc 09219 Efeito da irradiacao de superficies radiculares com laser de Er:YAG e diodo - analise termica e morfologica2002 - THEODORO, L.H.; HAYPEK, P.; BACHMANN, L.; GARCIA, V.G.; ZEZELL, D.M.; SAMPAIO, J.E.C.Resumo IPEN-doc 09197 Analise do comportamento termico do laser de diodo no esmalte, dentina e cemento dental - estudo in vitro2002 - PELINO, J.E.P.; HAYPEK, P.; SOARES, S.C.G.; BACHMANN, L.; ZEZELL, D.M.; EDUARDO, C.P.Resumo IPEN-doc 17465 Mechanisms of high intensity lasers for caries prevention and erosion2011 - ANA, P.A.; BACHMANN, L.; BENETTI, C.; GOULART, V.P.; ZEZELL, D.M.Resumo IPEN-doc 10365 Formação de centros paramagnéticos em esmalte e dentina aquecidos2004 - BACHMANN, L.; ZEZELL, D.M.; OSWALDO, BAFRAAlém de radiações ionizantes outros agentes podem produzir centros paramagnéticos em esmalte e dentina: aquecimento, moagem, radiação solar e ultravioleta. Estes radicais apresentam sinais paramagnéticos com propriedades similares aos sinais dosimétricos e por esta razio podem introduzir erros nos espectros dos tecidos mineralizados irradiados. O objetivo deste trabalho é estudar o comportamento dos centros paramagnéticos formados em esmalte e dentina aquecidos entre 100 °C e 1000 °C. Utilizaram-se amostras de esmalte e dentina bovinos em forma de pé. Os experimentos de ressonância paramagnética eletrônica foram conduzidos num espectrômetro Varian E-4, com cavidade retangular TE-102 e operando na banda X (9 GHz). Os tratamentos térmicos foram conduzidos em fornos em atmosfera de ar, com temperaturas entre 100 °C e 1000 °C com tempo de aquecimento de 30 minutos. As amostras utilizadas não apresentaram sinal antes do aquecimento. O esmalte apresentou sinais paramagnéticos quando aquecido entre 300 °C e 1000 °C e a dentina entre 100 °C e 1000 °C. Os sinais observados na dentina aquecida entre 100 °C e 200 °C são reversíveis após seis meses de estocagem, enquanto que as demais amostras aquecidas acima de 200 °C e as amostras de esmalte não apresentaram variações na amplitude entre as medidas realizadas logo após o aquecimento com a amplitude determinada após seis meses de estocagem. Com a evolução do tratamento térmico ocorre a diminuição do valor de g e da largura dos sinais em ambos os tecidos. No esmalte aquecido estes valores apresentam uma repentina diminuição em torno de 500 ©C: o valor de g decresce de 2,0066 (300-500 °C) para 2,0057 (500-900 °C) e a largura decresce de 0,7 mT para 0,3 mT. Na dentina o valor de g decresce de 2,0074 (225 °C) para 2,0057 (950 °C) e a largura decresce de 1,2 mT (150 °C) para 0,35 mT (950 °C). Apesar da determinação da origem dos radicais paramagnéticos observados ainda não estar bem estabelecida, os processos responsáveis por estes sinais possivelmente são: eliminação da água adsorvida, alteração da estrutura do colágeno, degradação da matriz orgânica, formação de cianato, eliminação de água estrutural e formação de defeitos cristalinos.Resumo IPEN-doc 10360 Lasers in caries diagnosis and prevention2005 - ZEZELL, D.M.; ANA, P.A.; RIBEIRO, A.C.; FREITAS, A.Z.; ROCHA, R.M.; OLIVEIRA, M.E.; BACHMANN, L.