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1.
Oral Radiol ; 37(4): 591-599, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33386527

RESUMO

OBJECTIVE: The aim of this study was to correlate the absence of BB with skeletal patterns and incisor inclination using cone-beam computed tomography (CBCT). METHODS: The sample comprised CBCT images of 45 patients undergoing orthodontic treatment. BB was classified in each third of the anterior teeth as critical, slender, regular, and thick. The skeletal pattern was determined by the ANB (A point, nasion, B point) angle and the incisor inclination using the 1.NA and 1.NB measurements and the interincisal angle (1:1). RESULTS: In both analyses, the skeletal pattern of class II revealed better BB in the cervical and middle thirds than classes I and III. A higher proportion of critical BB was found in the middle thirds, and the apical third presented the best regular and thick BB conditions, mainly class I. Less BB was observed in middle and apical thirds in the upper incisors and in cervical thirds in lower incisors, mostly when they were more upright. CONCLUSIONS: Knowledge of alveolar bone height and thickness can alter the treatment plan in orthodontics. During orthodontic treatment, more attention should be paid to the lower incisors and vertical teeth because of poor BB conditions, especially in class III skeletal patterns.


Assuntos
Incisivo , Má Oclusão Classe III de Angle , Cefalometria , Tomografia Computadorizada de Feixe Cônico , Humanos , Incisivo/diagnóstico por imagem , Mandíbula/diagnóstico por imagem
2.
Anal Bioanal Chem ; 397(7): 2667-76, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20174784

RESUMO

A survey of gilts applied to stucco surfaces that specifically focuses on the compositions of their colored grounds is reported. Gilt samples of a common geographical (Lombardy in Italy) and temporal provenance (17th-18th century) were studied in the form of polished cross-sections by optical and electron microscopy (SEM-EDS), micro-Raman (microRaman) spectroscopy and Fourier-transform infrared microspectroscopy (microFTIR). Comparing samples with superimposed grounds and gilts enabled light to be shed on the choice of specific materials, their stratigraphic functions, decorative effects, and technological performances. Iron oxide pigments were found in the older grounds, sometimes in the presence of lead white (2PbCO(3).Pb(OH)(2)) or minium (Pb(3)O(4)). In more recent grounds, chrome yellow (PbCrO(4)), chrome orange (PbCrO(4).PbO), cinnabar (alpha-HgS) and barium white (BaSO(4)), invariably mixed with lead white, were encountered. Evidence for the use of organic mordants (colophony and wax, or siccative oil) was obtained by microFTIR. This combined microFTIR and microRaman spectroscopic and elemental (SEM-EDS) analytical approach enhances knowledge of the composition of gold grounds, their variability and their chronological evolution.

3.
Anal Bioanal Chem ; 397(2): 841-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20225056

RESUMO

One degradation phenomenon that occurs in artworks is the formation of metal oxalates on their surfaces. In order to gain insight into the inclination of pigments to produce oxalates, nine pigments including Na, Ca, Fe, Pb and Cu cations were selected to react with oxalic acid solutions at different concentrations (1 M, 0.1 M, 0.01 M and 0.005 M). Micro-Raman spectroscopy was used to detect the different reaction products. Pigments containing calcium (calcite, gypsum and Volterra gypsum) showed a high tendency to form weddellite as well as whewellite, especially at high acidic concentrations; among copper-based pigments (malachite, azurite, verdigris), the formation of moolooite was observed for high concentrations of acid and down to the lowest concentration (0.005 M) in the case of verdigris. Lead oxalate was detected on lead white. No iron oxalates were observed for hematite; the formation of calcium oxalate crystals was observed instead. Ultramarine blue reacted to produce elemental sulfur. According to the results obtained, calcite and verdigris showed the highest reactivity in oxalic acid environments, resulting in a high tendency to form calcium and copper oxalates, even at very low acidic concentrations; this behavior seems to arise from the high solubilities of these pigments in acidic environments.

4.
Anal Bioanal Chem ; 394(4): 1033-41, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19214480

RESUMO

A nanosecond pulsed laser setup has been optimized to perform laser-induced breakdown spectroscopy (LIBS) and pulsed Raman spectroscopy measurements in the field of cultural heritage. Three different samples of artistic/architectural interest with different typologies have been analyzed. The results from the two techniques allowed the identification of the materials used in their manufacture or contaminating them, probably coming from atmospheric pollution and biological activity. No sampling and sample preparation was required before the measurements, and no visual or structural damage was observed. Depth profiling using LIBS was performed in one of the samples, providing elemental information along the different layers composing the object and covering its surface. The quality of the results and the rather short time needed for the measurements and for switching between techniques confirmed the instrument's capabilities and specificity for dealing with objects of artistic or historical interest.


Assuntos
Arte , Lasers , Análise Espectral/métodos , Análise Espectral Raman/métodos
5.
J Phys Chem A ; 113(52): 14343-51, 2009 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-19813719

RESUMO

The gas phase structures of anisole dimer in the ground and first singlet electronic excited states have been characterized by a combined experimental and computational study. The dimer, formed in a molecular beam, has been studied by resonance-enhanced multiphoton ionization and high-resolution laser-induced fluorescence techniques. The assignment of the rotational fine structure of the S(1) <-- S(0) electronic transition origin has provided important structural information on the parallel orientation of aromatic rings of anisole moieties. By comparison with the DFT/TD-DFT computational results, it has been possible to infer the detailed equilibrium structure of the complex. The analysis of the equilibrium structure and interaction energy confirms that the anisole dimer is stabilized by dispersive interaction in the gas phase. This is, to the best of our knowledge, the first detailed work (reporting both theoretical and high-resolution experimental data) on an isolated cluster in the pi-stacking configuration.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 137: 677-84, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25247839

RESUMO

The analysis of ground state structural and vibrational properties of Safranin-O is presented. The experimental results, obtained by FTIR, Raman and SERS spectroscopy, are discussed in comparison to the results of DFT calculations carried out at the B3LYP/6-311+G(d,p) level of theory. The calculated spectra reproduce quite satisfactorily the experimental data. The calculated Safranin-O equilibrium structure and the assignment of the vibrational spectra are reported as well. From the changes between Raman and SERS spectra a model is presented for the interaction of Safranin-O with silver nanoparticles.


Assuntos
Corantes/química , Fenazinas/química , Espalhamento a Baixo Ângulo , Prata/química , Espectrofotometria Infravermelho , Análise Espectral Raman , Adsorção , Elétrons , Nanopartículas Metálicas/química , Conformação Molecular , Nanotecnologia , Software , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Vibração , Água/química
7.
Ann N Y Acad Sci ; 784: 496-508, 1996 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-8651605

RESUMO

Monoclonal antibodies specific for protein markers of smooth muscle and nonmuscle cell differentiation were applied to cryosections of normal, hyperplastic, and neoplastic human prostate specimens in order to determine whether differences in the distribution of target antigens could be detected among the various tissues. Immunofluorescence assays showed that vimentin, desmin, smooth-muscle-type alpha-actin, and both smooth muscle and nonmuscle myosin heavy chains do not change their patterns of labeling in the stromas of normal, BPH, and carcinomatous prostates. By contrast, cytokeratin 18, a differentiation marker of simple epithelia, and to a lesser extent cytokeratin 8, was consistently found in stromal tissue of the "transition zone", but only scarcely in the stroma of the "peripheral zone" from normal prostate, and was completely unexpressed in benign hyperplasia. Prostatic carcinoma from the "peripheral zone" expressed this cytoskeletal component only in trace amounts. Moreover, in prostate showing coexistence of hyperplasia and neoplasia (in the "peripheral zone"), the stroma of BPH closely resembled the stroma surrounding the carcinoma; that is, it was completely unreactive with the anti-cytokeratin 18 antibody. Expression of cytokeratins in extraepithelial tissues has been previously correlated with the achievement of a proliferative state, notably in embryogenesis, in tissue regeneration, and in various pathological forms of proliferation and growth, including some tumors of mesenchymal origin. Our results indicate the following: (1) cells in the stromal tissue of normal prostate are of smooth muscle type and are heterogeneous as concerns cytokeratin distribution; (2) we show, for the first time, the existence of a marker that is differentially distributed in the "transition" versus "peripheral" zone; (3) the expression of cytokeratins in the stroma is lost with the development of hyperplasia and only partially recovers with neoplasia; (4) the pattern of stromal tissue, concerning cytokeratin 18 expression, does not change with different BPH locations ("transition" versus "peripheral" zone); and (5) contrary to expectations, cytokeratin 18 expression disappears in conditions presumably involving stromal cell proliferation.


Assuntos
Proteínas Contráteis/análise , Proteínas do Citoesqueleto/análise , Próstata/química , Hiperplasia Prostática/metabolismo , Neoplasias da Próstata/química , Adulto , Idoso , Anticorpos Monoclonais , Imunofluorescência , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Próstata/citologia , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia , Células Estromais/química
8.
Urology ; 55(5): 710-5, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10792086

RESUMO

OBJECTIVES: To ascertain when the serum determination of the free prostate-specific antigen (PSA)/total PSA (fPSA/tPSA) ratio is clinically useful, and whether the identification of PSA or prostate-specific membrane antigen (PSM) mRNA in circulating cells has diagnostic advantages over the determination of their protein product. METHODS: fPSA, tPSA, and the fPSA/tPSA ratio were determined in the sera of 50 men with benign nonprostatic urologic diseases (EPD), 112 patients with prostate cancer (PCa), and 218 with benign prostatic hyperplasia (BPH). mRNA was extracted from the circulating mononuclear cells of 13 EPD samples, 25 PCa samples, and 38 BPH samples. PSA and PSM mRNA signals were identified in these samples by means of reverse transcriptase-polymerase chain reaction. RESULTS: Overall, at a fixed specificity of 95%, the sensitivity of tPSA was 19% and that of the fPSA/tPSA ratio was 40% in distinguishing PCa from BPH. The fPSA/tPSA ratio allowed the discrimination of PCa from BPH with satisfactory sensitivity and specificity when considering patients less than 60 years of age (100% and 95%, respectively). PSA and PSM mRNA were positive in 1 and 7 of 13 EPD samples, 6 and 13 of 25 PCa samples, and 6 and 17 of 38 BPH samples. The Gleason score did not correlate with tPSA, the fPSA/tPSA ratio, PSA mRNA, or PSM mRNA. CONCLUSIONS: The serum determination of the fPSA/tPSA ratio is an excellent index of PCa for subjects younger than 60 years of age; the clinical utility of PSA mRNA identification in circulating cells needs to be validated by large follow-up studies, and the analysis of PSM mRNA seems to be of no clinical interest.


Assuntos
Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/genética , Hiperplasia Prostática/sangue , RNA Mensageiro/sangue , Sensibilidade e Especificidade
9.
Ann Chim ; 91(11-12): 833-41, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11836961

RESUMO

New applications of micro-Raman spectroscopy are presented here for the investigation of colouring agents in a wax model of plant and of corrosion products on metal artworks. A late 1700 wax model of Camellia japonica L. was studied in order to characterise the nature of white, red and green colours of petals and leaves. White and red colours of petals were identified as pigments of baryte and a mixture of cinnabar and carmine lake, respectively. Fragments taken from leaves with different green hues were also studied; only yellow grains were isolated in this case which were identified as orpiment and yellow chrome. The applicability of micro-Raman spectroscopy to the study of corrosion products on metal objects is presented here for iron archaeological artefacts and for lead samples taken from the cupolas of the Consolata Sancturay in Turin. Analysis of blackish and reddish corrosion patinas entirely covering the archaeological iron objects led to the identification of magnetite and maghemite, goethite and lepidocrocite, respectively. As to lead fragments, the main corrosion product was lead sulphate, and minor amounts of lead carbonate, nitrate and oxide (litharge) were also found.


Assuntos
Ferro/química , Chumbo/química , Pigmentos Biológicos/química , Escultura/história , Corrosão , História do Século XVII , História do Século XVIII , Itália , Pigmentos Biológicos/história , Análise Espectral Raman , Ceras/análise
10.
Dental Press J Orthod ; 19(3): 95-101, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25162572

RESUMO

OBJECTIVE: This study aimed at assessing, in vivo, whether the prior use of 0.12% chlorhexidine as mouthwash would decrease air contamination caused by aerosolized sodium bicarbonate during dental prophylaxis. The study was conducted with 23 patients aged between 10 and 40 years old who were randomly selected and undergoing fixed orthodontic treatment. METHODS: The study was divided into two phases (T1 and T2) with a 30-day interval in between. In both phases, dental prophylaxis was performed with aerosolized sodium bicarbonate jetted to the upper and lower arches for 4 minutes. In T1, 10 minutes before the prophylaxis procedure, the participants used distilled water as mouthwash for one minute; whereas in T2, mouthwash was performed with 0.12% chlorhexidine. Microbial samples were collected in BHI agar plates for microbiological analysis. Two dishes were positioned on the clinician (10 cm from the mouth) and a third one at 15 cm from the patient's mouth. The samples were incubated for 48 hours at 37°C. Results were expressed in colony-forming units (CFU). RESULTS: Statistical analysis carried out by means of Student's t test, as well as Wilcoxon and Kruskal-Wallis tests revealed that the prior use of 0.12% chlorhexidine as mouthwash significantly reduced CFU in the three positions studied (P < 0.001). CONCLUSION: The prior use of 0.12% chlorhexidine as mouthwash significantly reduced contamination caused by aerosolized sodium bicarbonate during dental prophylaxis in the orthodontic clinic.


Assuntos
Microbiologia do Ar , Poluição do Ar em Ambientes Fechados/prevenção & controle , Anti-Infecciosos Locais/uso terapêutico , Clorexidina/uso terapêutico , Profilaxia Dentária/métodos , Antissépticos Bucais/uso terapêutico , Ortodontia Corretiva , Bicarbonato de Sódio/uso terapêutico , Adolescente , Adulto , Aerossóis , Bactérias/isolamento & purificação , Carga Bacteriana , Criança , Profilaxia Dentária/instrumentação , Feminino , Humanos , Estudos Longitudinais , Masculino , Aparelhos Ortodônticos , Bicarbonato de Sódio/administração & dosagem , Adulto Jovem
11.
Dental Press J Orthod ; 18(2): 20.e1-8, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23916448

RESUMO

OBJECTIVE: The purpose of this laboratory study was to evaluate changes in the pigmentation of esthetic elastomeric ligatures after immersion in a staining solution. METHODS: Sixty ligatures were selected and divided into 12 groups according to their brand and also considering their condition, i.e., unstretched or stretched. The groups were divided into: Morelli (clear), TP Orthodontics (clear), American Orthodontics (clear), 3M/Unitek (clear), American Orthodontics (pearl color) and 3M/Unitek (pearl color), separated in groups of 5 unstretched and 5 stretched ligatures. Assessment of their color changes was performed by means of digital photograph and computer analysis using Adobe Photoshop. Standardized digital photographs were taken at T0 (before the staining process, with unstretched ligatures) and at T1 (following the 5-days staining process). The staining solution was composed of artificial saliva and foods with staining potential. At T1 the ligatures were either stretched or unstretched. RESULTS: The results of this study showed that esthetic elastomeric ligatures are prone to staining. Among the evaluated brands, TP Orthodontics and American Orthodontics clear ligatures were the most stable. Moreover, 3M/Unitek pearl ligatures demonstrated statistically significant changes in all variables. CONCLUSIONS: Esthetic elastomeric ligatures are susceptible to staining and no statistically significant difference was found between unstretched or stretched ligatures, with the sole exception of the TP Orthodontics brand. The 3M/Unitek's pearl color ligatures displayed the greatest staining potential.


Assuntos
Cor/normas , Elastômeros/química , Aparelhos Ortodônticos , Pigmentos Biológicos , Análise de Variância , Teste de Materiais , Fotografação/instrumentação , Fotografação/métodos , Saliva Artificial , Software
12.
Artigo em Inglês | MEDLINE | ID: mdl-19129003

RESUMO

Pulsed laser induced breakdown spectroscopy (LIBS) and Raman spectroscopy were performed using a novel laboratory setup employing the same Nd:YAG laser emission at 532 nm for the analysis of five commercially available pigments collectively known as "ultramarine blue", a sodium silicate material of either mineral origin or an artificially produced glass. LIBS and Raman spectroscopy have provided information regarding the elemental and molecular composition of the samples; additionally, an analytical protocol for the differentiation between natural (lapis lazuli) and artificial ultramarine blue pigments is proposed. In particular LIBS analysis has allowed the discrimination between pigments on the basis of peaks ascribed to calcium. The presence of calcite in the natural blue pigments has been confirmed following Raman spectroscopy in specific areas of the samples, and micro-Raman and optical microscopy have further corroborated the presence of calcite inclusions in the samples of natural origin. Finally multivariate analysis of Laser induced breakdown spectra using principal component analysis (PCA) further enhanced the differentiation between natural and artificial ultramarine blue pigments.


Assuntos
Silicatos de Alumínio/análise , Corantes/análise , Lasers , Análise Espectral Raman/instrumentação , Análise Espectral Raman/métodos , Desenho de Equipamento , Microscopia de Polarização , Análise de Componente Principal
13.
Rev Sci Instrum ; 80(7): 076109, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19655994

RESUMO

A small, potentially transportable prototype instrument capable of carrying out Raman, laser-induced breakdown (LIB), and laser-induced fluorescence (LIF) spectroscopy using a single pulsed laser source was developed for the analysis of cultural heritage objects. The purpose of this instrumentation is to perform fast and reliable analysis of surfaces with minimum damage to an object. For this purpose, a compact (51 x 203 x 76 mm) nanosecond Q-switched neodymium doped yttrium aluminum garnet laser (8 ns, 20 Hz, 0.01-115 mJ/pulse) was used as an irradiation source. The use of a nanosecond-gated detector sensitive between 180 and 900 nm allows the acquisition of elemental emissions in LIB spectroscopy and can also be employed for both LIF and time-resolved Raman spectroscopy. In this work, attention is focused on the description of the instrument and its optical components, and two examples of applications for the analysis of pigments and binding media used in works of art are presented.

14.
Dental press j. orthod. (Impr.) ; 19(3): 95-101, May-Jun/2014. graf
Artigo em Inglês | LILACS | ID: lil-723146

RESUMO

OBJECTIVE: This study aimed at assessing, in vivo, whether the prior use of 0.12% chlorhexidine as mouthwash would decrease air contamination caused by aerosolized sodium bicarbonate during dental prophylaxis. The study was conducted with 23 patients aged between 10 and 40 years old who were randomly selected and undergoing fixed orthodontic treatment. METHODS: The study was divided into two phases (T1 and T2) with a 30-day interval in between. In both phases, dental prophylaxis was performed with aerosolized sodium bicarbonate jetted to the upper and lower arches for 4 minutes. In T1, 10 minutes before the prophylaxis procedure, the participants used distilled water as mouthwash for one minute; whereas in T2, mouthwash was performed with 0.12% chlorhexidine. Microbial samples were collected in BHI agar plates for microbiological analysis. Two dishes were positioned on the clinician (10 cm from the mouth) and a third one at 15 cm from the patient's mouth. The samples were incubated for 48 hours at 37°C. Results were expressed in colony-forming units (CFU). RESULTS: Statistical analysis carried out by means of Student's t test, as well as Wilconxon and Kruskal-Wallis tests revealed that the prior use of 0.12% chlorhexidine as mouthwash significantly reduced CFU in the three positions studied (P < 0.001). CONCLUSION: The prior use of 0.12% chlorhexidine as mouthwash significantly reduced contamination caused by aerosolized sodium bicarbonate during dental prophylaxis in the orthodontic clinic. .


OBJETIVO: avaliar, in vivo, se a utilização prévia do bochecho com clorexidina a 0,12% diminui a contaminação do ar gerada pelo jato de bicarbonato de sódio durante a profilaxia dentária. O estudo foi realizado com 23 pacientes, na faixa etária entre 10 e 40 anos, escolhidos aleatoriamente, que faziam uso de aparelho ortodôntico fixo. MÉTODOS: o estudo foi dividido em duas fases (T1 e T2), com intervalo de 30 dias entre elas. Em ambas, foi realizada profilaxia dentária com jato de bicarbonato de sódio na arcada superior e inferior, durante quatro minutos. Em T1, 10 minutos antes do procedimento, os participantes realizaram bochecho com água destilada durante um minuto, e, em T2, o bochecho foi realizado com clorexidina a 0,12%. Amostras dos microrganismos foram coletadas em placas de ágar BHI para análise microbiológica, sendo duas placas posicionadas no profissional (a 10cm da boca) e uma terceira a 15cm da boca do paciente. Após a coleta, as placas foram incubadas por 48 horas a 37°C. O resultado foi expresso em número de unidades formadoras de colônias (UFC). RESULTADOS: após análise estatística utilizando teste t de Student, teste de Wilconxon e teste de Kruskal-Wallis, observou-se que o bochecho prévio com clorexidina a 0,12% reduziu significativamente a média de UFC nas três posições estudadas (p < 0,001). CONCLUSÃO: os resultados permitem concluir que o bochecho prévio com clorexidina a 0,12% proporcionou uma redução estatisticamente significativa na contaminação gerada por meio do jato de bicarbonato de sódio durante a profilaxia dentária na clínica ortodôntica. .


Assuntos
Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Adulto Jovem , Microbiologia do Ar , Poluição do Ar em Ambientes Fechados/prevenção & controle , Anti-Infecciosos Locais/uso terapêutico , Clorexidina/uso terapêutico , Profilaxia Dentária/métodos , Antissépticos Bucais/uso terapêutico , Ortodontia Corretiva , Bicarbonato de Sódio/uso terapêutico , Aerossóis , Carga Bacteriana , Bactérias/isolamento & purificação , Profilaxia Dentária/instrumentação , Estudos Longitudinais , Aparelhos Ortodônticos , Bicarbonato de Sódio/administração & dosagem
15.
Dental press j. orthod. (Impr.) ; 18(2): 20e1-20e8, Mar.-Apr. 2013. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-683178

RESUMO

OBJECTIVE: The purpose of this laboratory study was to evaluate changes in the pigmentation of esthetic elastomeric ligatures after immersion in a staining solution. METHODS: Sixty ligatures were selected and divided into 12 groups according to their brand and also considering their condition, i.e., unstretched or stretched. The groups were divided into: Morelli (clear), TP Orthodontics (clear), American Orthodontics (clear), 3M/Unitek (clear), American Orthodontics (pearl color) and 3M/Unitek (pearl color), separated into groups of 5 unstretched and five stretched ligatures. Assessment of their color changes was performed by means of digital photograph and computer analysis using Adobe Photoshop. Standardized digital photographs were taken at T0 (before the staining process, with unstretched ligatures) and at T1 (following the 5-days staining process). The staining solution was composed of artificial saliva and foods with staining potential. At T1 the ligatures were either stretched or unstretched. RESULTS: The results of this study showed that esthetic elastomeric ligatures are prone to staining. Among the evaluated brands, TP Orthodontics and American Orthodontics clear ligatures were the most stable. Moreover, 3M/Unitek pearl ligatures demonstrated statistically significant changes in all variables. CONCLUSIONS: Esthetic elastomeric ligatures are susceptible to staining and no statistically significant difference was found between unstretched or stretched ligatures, with the sole exception of the TP Orthodontics brand. The 3M/Unitek's pearl color ligatures displayed the greatest staining potential.


OBJETIVO: avaliar alterações da pigmentação de ligaduras elásticas estéticas após imersão em solução de pigmentação. MÉTODOS: Sessenta ligaduras foram selecionadas e divididas em doze grupos de acordo com a marca comercial utilizada e nas condições normal e distendida. Os grupos foram divididos em: Morelli transparente, TP Orthodontics transparente, American Orthodontics transparente, Unitek/3M transparente, American Orthodontics pérola e Unitek/3M pérola, separados quanto à condição normal e distendida, totalizando 5 ligaduras em cada condição. A avaliação das mudanças de coloração foi realizada por meio de fotografia digital e análise computadorizada usando o programa Adobe Photoshop. Foram realizadas fotografias digitais padronizadas nos tempos T0 - antes do processo de pigmentação, com as ligaduras em estado normal; e T1 - após o processo de pigmentação, que durou cinco dias. A solução de pigmentação utilizada foi composta por saliva artificial e por alimentos que possuem potencial de coloração. No tempo T1, as ligaduras se encontravam em estado distendido e em estado normal (sem distensão). RESULTADO: os resultados do presente estudo demonstraram que ligaduras elásticas estéticas são suscetíveis à pigmentação. Dentre as marcas comerciais avaliadas a TP Orthodontics e American Orthodontics transparente foram as mais estáveis. Já a Unitek/3M pérola demonstrou alterações estatisticamente significativas em todas as variáveis avaliadas. CONCLUSÃO: ligaduras elásticas estéticas são suscetíveis à pigmentação, não havendo diferença estatisticamente significativa entre o estado normal e o estado distendido, com exceção na marca TP Orthodontics. A marca Unitek/3M pérola demonstrou ser a que apresenta maior potencial para pigmentação.


Assuntos
Cor/normas , Elastômeros/química , Aparelhos Ortodônticos , Pigmentos Biológicos , Análise de Variância , Teste de Materiais , Fotografação/instrumentação , Fotografação/métodos , Saliva Artificial , Software
16.
Dental press j. orthod. (Impr.) ; 17(5): 43-52, Sept.-Oct. 2012. ilus
Artigo em Inglês | LILACS | ID: lil-656738

RESUMO

INTRODUCTION: A female patient aged 12 years and 2 months had molars and canines in Class II relationship, severe overjet (12 mm), deep overbite (100%), excessive retroclination and extrusion of the lower incisors, upper incisor proclination, with mild midline diastema. Both dental arches appeared constricted and a lower arch discrepancy of less than -6.5 mm. Facially, she had a significant upper incisors display at rest, interposition and eversion of the lower lip, acute nasolabial angle and convex profile. OBJECTIVE: To report a clinical case consisting of Angle Class I malocclusion with deep overbite and overjet in addition to severe crowding treated with a conservative approach. METHODS: Treatment consisted of slight retraction of the upper incisors and intrusion and protrusion of the lower incisors until all crowding was eliminated. RESULTS: Adequate overbite and overjet were achieved while maintaining the Angle Class I canine and molar relationships and coincident midlines. The facial features were improved, with the emergence of a slightly convex profile and lip competence, achieved through a slight retraction of the upper lip and protrusion of the lower lip, while improving the nasolabial and mentolabial sulcus. CONCLUSIONS: This conservative approach with no extractions proved effective and resulted in a significant improvement of the occlusal relationship as well as in the patient's dental and facial aesthetics.


INTRODUÇÃO: paciente do sexo feminino, 12 anos e 2 meses de idade, apresentava molares em relação de chave de oclusão e caninos em relação de Classe II de Angle, sobressaliência acentuada (12mm), sobremordida profunda (100%), excessiva retroinclinação e extrusão dos incisivos inferiores e projeção dos superiores, com leves diastemas interincisais. Ambas as arcadas apresentavam-se constritas e a discrepância dentária inferior era de -6,5mm. Do ponto de vista facial, apresentava grande exposição dos incisivos superiores em repouso, interposição e eversão do lábio inferior, ângulo nasolabial agudo e perfil convexo. OBJETIVO: apresentar um caso clínico de má oclusão de Classe I com sobremordida e sobressaliência acentuadas, além de apinhamento severo, tratado com método conservador. MÉTODOS: o tratamento foi constituído de leve retração e intrusão dos incisivos superiores, e projeção dos incisivos inferiores até que todo o apinhamento fosse eliminado. RESULTADOS: obteve-se sobremordida e sobressaliência satisfatórias, manutenção da relação de chave de oclusão nos molares e obtenção dessa relação nos caninos e linhas médias coincidentes. As características faciais obtidas foram positivas, originando um perfil bastante agradável, com selamento labial passivo, promovido pela leve retração do lábio superior e projeção do lábio inferior, melhorando o ângulo nasolabial e o mentolabial. CONCLUSÃO: a abordagem conservadora, sem exodontias, mostrou-se efetiva e resultou em sensível melhora do relacionamento oclusal e da estética dentária e facial da paciente.

17.
Dental press j. orthod. (Impr.) ; 16(1): 99-106, jan.-fev. 2011. ilus, graf
Artigo em Português | LILACS | ID: lil-580320

RESUMO

OBJETIVO: determinar a relação entre as alturas faciais obtidas na avaliação do tegumento e do esqueleto subjacente, na análise da proporção facial vertical, na região anterior. MÉTODOS: foram utilizadas 24 radiografias cefalométricas de perfil e 48 fotografias da face, sendo 24 de perfil e 24 frontais, pertencentes a 24 indivíduos brasileiros, 7 do sexo masculino e 17 do feminino, na faixa etária de 19 a 38 anos. Foram realizados traçados cefalométricos e, sobre esses, obtidas medidas lineares, segundo as análises preconizadas por Schudy, Wylie e Johnson e Thompson e Brodie. Sobre as fotografias faciais, foram demarcados os pontos glabela, subnasal e mento, o que permitiu a medição das distâncias lineares entre os mesmos. Os dados obtidos foram, então, tratados estatisticamente. RESULTADOS E CONCLUSÕES: encontrou-se correlação positiva entre as avaliações do tegumento e do esqueleto subjacente, com base nas análises de Schudy (r=0,619, p<0,001), Wylie e Johnson (r=0,595, p<0,002) e Thompson e Brodie (r=0,630, p<0,001), embora, individualmente, algumas discordâncias tenham sido identificadas, devido à variabilidade em espessura nos tecidos moles.


OBJECTIVE: To determine the relationship between facial heights by evaluating the soft tissues and underlying skeleton and by analyzing vertical facial proportions in the anterior region. METHODS: The study used 24 lateral cephalometric x-rays and 48 photographs of the face, 24 in profile view and 24 in front view, belonging to 24 Brazilian individuals, 7 men and 17 women whose ages ranged from 19 to 38 years. Cephalometric tracings were performed and linear measurements obtained according to the analyses suggested by Schudy, Wylie & Johnson, and Thompson & Brodie. The anatomical landmarks glabella, subnasal and menton were identified on the photographs, which allowed the measurement of linear distances between these points. The data were then statistically analyzed. RESULTS AND CONCLUSIONS: A positive correlation was found between evaluations of the soft tissues and underlying skeleton based on the analyses advanced by Schudy (r=0.619, p<0.001), Wylie & Johnson (r=0.595, p<0.002) and Thompson & Brodie (r=0.630, p<0.001), although, individually, some discrepancies were identified due to variability in soft tissue thickness.


Assuntos
Humanos , Masculino , Feminino , Adulto , Cefalometria , Face , Ortodontia
18.
Ortho Sci., Orthod. sci. pract ; 9(34): 53-64, 2016.
Artigo em Português | LILACS, BBO | ID: biblio-831171

RESUMO

Com o aumento da demanda por reabilitações através de implantes dentários, tornou-se mais frequente a movimentação ortodôntica dos dentes remanescentes, muitas vezes inclinados na direção da perda dentária e/ou associados a perdas periodontais. Nestes casos, é importante o conhecimento da biomecânica ortodôntica apropriada para esse tipo de paciente. O objetivo desse trabalho foi apresentar o tratamento de três pacientes adultos com indicação de preparo ortodôntico para posterior reabilitação oral, com especial enfoque à biomecânica utilizada. No primeiro e segundo pacientes, havia perda dentária inferior, com inclinação para mesial dos dentes distais ao espaço edêntulo. Nos dois casos, foi utilizada uma alça de verticalização de molares de forma quadrangular, confeccionada com fio 0,018” x 0,025” TMA, inserida por distal na entrada auxiliar do tubo dos molares inferiores. Este movimento de verticalização viabilizou a instalação de próteses nestes pacientes, em um tempo de 5 a 6 meses, e com poucos efeitos adversos nos incisivos inferiores. Na segunda paciente, os mini-implantes permitiram uma ancoragem ideal para distalização do canino superior direito e correção da linha média superior. No terceiro caso, a paciente apresentava extrusão dos molares e pré-molar superior direito. Foram utilizados mini-implantes para a intrusão desses dentes. Nos três casos, essas movimentações permitiram o correto planejamento das próteses e restabelecimento da função mastigatória. Portanto, quando os princípios de biomecânica ortodôntica são corretamente empregados, mesmo em casos considerados complexos, é possível obter uma boa oclusão, saúde periodontal, estética, função, além da melhora da qualidade de vida e autoestima do paciente.


The increasing demand for rehabilitation through dental implants made more frequent the need for orthodontic movement of remaining teeth often inclined towards tooth loss area and/or associated with periodontal loss. In these cases, it is important to know which orthodontic biomechanics is specifically suitable for this type of patient. The aim of this study was to present the treatment of three adult patients with orthodontic preparation indication for further oral rehabilitation, focusing on biomechanics. The first and second patients, presented loss of lower teeth, with mesial inclination of distal teeth to the edentulous space. In both cases, it was used an auxiliary vertical handle made with 0.018” x 0.025 “TMA wire, inserted by the distal end of the lower molars tubes. This uprighting movement allowed the installation of prostheses in these patients, in a period of 5 to 6 months, with few adverse effects on the lower incisors. Mini-implants were also used in the second patient, allowing anchorage for distalization of the upper right canine and upper midline correction. In the third reported case, the patient presented extrusion of molars and right upper bicuspid. Mini-implants were used to intrude these teeth. In all three cases, these movements enabled the correct planning of the prosthetic and restoration of masticatory function. Therefore, when the principles of orthodontic biomechanics are properly used, even in complex cases, one can get a good occlusion, restore periodontal health, aesthetics and function, thus improving patients’ quality of life and self-esteem.


Assuntos
Reabilitação Bucal , Técnicas de Movimentação Dentária , Ortodontia
19.
Dental press j. orthod. (Impr.) ; 15(4): 62-68, jul.-ago. 2010. ilus, graf, tab
Artigo em Português | LILACS | ID: lil-555735

RESUMO

OBJETIVO: avaliar a atividade antimicrobiana da associação de um adesivo ortodôntico com um verniz de clorexidina e timol. MÉTODOS: foram utilizados 32 pré-molares humanos divididos em 4 grupos. O grupo 1 consistiu do grupo controle, no qual o adesivo utilizado para a colagem do braquete não estava associado a nenhum agente antimicrobiano. Os grupos 2, 3 e 4 foram colados com um sistema adesivo associado a um verniz de clorexidina e timol. Os grupos 3 e 4 foram armazenados em água por 7 dias e 30 dias, respectivamente, enquanto os corpos de prova do grupo 2 foram, logo depois da colagem, colocados em ágar semeado com Streptococcus mutans por 48h a 37ºC. RESULTADOS: os grupos experimentais, com exceção do grupo controle, apresentaram atividade antimicrobiana com tendência de redução do seu potencial de ação com maior tempo de imersão em água. CONCLUSÃO: a associação do verniz de clorexidina a um sistema adesivo utilizado em Ortodontia apresenta-se vantajosa pela sua atividade antimicrobiana.


OBJECTIVE: To assess the antimicrobial activity resulting from the association of an orthodontic adhesive with chlorhexidine-thymol varnish. METHODS: Thirty-two extracted human premolars were used, divided into four groups. In Group 1, the control group, the adhesive used to bond the bracket was not associated with any antimicrobial agent. Groups 2, 3 and 4 were bonded with an adhesive system associated with chlorhexidine-thymol varnish. Groups 3 and 4 were stored in water for 7 days and 30 days, respectively, while the specimens from group 2 were, soon after bonding, placed on agar seeded with Streptococcus mutans for 48 hours, at 37º C. RESULTS: The experimental groups, with the exception of the control group, showed antimicrobial activity whose action tended to decline commensurately with the amount of time that they remained immersed in water. CONCLUSIONS: The association of chlorhexidine-thymol varnish with an adhesive system used in orthodontics proved to be advantageous due to its antimicrobial activity.


Assuntos
Humanos , Antibacterianos , Clorexidina/administração & dosagem , Clorexidina/uso terapêutico , Adesivos Dentinários , Dente Pré-Molar , Crescimento Bacteriano/prevenção & controle , Higiene Bucal
20.
J Urol ; 157(2): 677-82, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8996397

RESUMO

PURPOSE: We asked whether a urethral constriction gradually developed during growth would give rise to a structural remodeling of the bladder wall distinct from that of the mature rabbits in terms of cellular response. MATERIALS AND METHODS: We examined the serosa and detrusor muscle in immature rabbits whose urethra was obstructed at 30 days postnatal and studied 7 to 30 days after partial outlet obstruction. Morphometry, bromo-deoxyuridine (BrdU) incorporation, Western blotting and immunocytochemical staining with a panel of monoclonal antibodies specific to selected cytoskeletal, cytocontractile and membrane-related proteins unique to non-muscle and smooth muscle cells (SMC) were used to analyze the effects of obstruction on the differentiation pattern. RESULTS: In comparison with results in adult obstructed bladders, we have found that in growing rabbits: (1) the cell conversion from fibroblasts to SMC, occurring within the 'extrinsic' region of serosal thickening, takes place earlier; (2) newly formed SMC are localized exclusively to the thickened serosa, and can group in bundles depending on the density of the regional innervation; (3) the peak level of BrdU incorporation is more elevated than in the adult bladder wall; and (4) change in the phenotypic profile of SMC of detrusor muscle is delayed. CONCLUSION: These data indicate that the basic features of structural remodeling in the two models are similar, though partial outlet obstruction produced in growing animals accelerates the fibroblast conversion to SMC and their spatial, differentiation-specific arrangement in the serosa. The late phenotypic changes in obstructed detrusor muscle correlate with the decline of the DNA synthesis level after an initial burst and strongly suggest that newly formed SMC in the serosa do not derive from pre-existing SMC.


Assuntos
Obstrução do Colo da Bexiga Urinária/patologia , Bexiga Urinária/crescimento & desenvolvimento , Bexiga Urinária/patologia , Animais , Divisão Celular , Masculino , Músculo Liso/patologia , Coelhos , Fatores de Tempo
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