Tomographic evaluation of buccal bone in different skeletal patterns and incisors inclination.

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.

Biomecânica ortodôntica no tratamento reabilitador bucal / Orthodontic biomechanics in oral rehabilitation treatment

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.

Safranin-O dye in the ground state. A study by density functional theory, Raman, SERS and infrared spectroscopy.

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.

Effect of 0.12% chlorhexidine in reducing microorganisms found in aerosol used for dental prophylaxis of patients submitted to fixed orthodontic treatment.

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.

Effect of 0.12% chlorhexidine in reducing microorganisms found in aerosol used for dental prophylaxis of patients submitted to fixed orthodontic treatment

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. .

Evaluation of the susceptibility to pigmentation of orthodontic esthetic elastomeric ligatures.

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.

Evaluation of the susceptibility to pigmentation of orthodontic esthetic elastomeric ligatures

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.

Conservative treatment of a Class I malocclusion with 12 mm overjet, overbite and severe mandibular crowding

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.

Avaliação da proporção facial vertical: relação entre as alturas tegumentar e esquelética / Evaluation of facial proportions in the vertical plane to investigate the relationship between skeletal and soft tissue dimensions

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.

Avaliação da atividade antimicrobiana de adesivo ortodôntico associado a verniz de clorexidina e timol na colagem de braquetes / Evaluation of antimicrobial activity of orthodontic adhesive associated with chlorhexidine-thymol varnish in bracket bonding

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.

Metal oxalates in paints: a Raman investigation on the relative reactivities of different pigments to oxalic acid solutions.

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.

Colored grounds of gilt stucco surfaces as analyzed by a combined microscopic, spectroscopic and elemental analytical approach.

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.

The gas phase anisole dimer: a combined high-resolution spectroscopy and computational study of a stacked molecular system.

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.

A new compact instrument for Raman, laser-induced breakdown, and laser-induced fluorescence spectroscopy of works of art and their constituent materials.

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.

Avaliação da radiografia cefalométrica lateral como meio de diagnóstico da hipertrofia de adenoide / Evaluation of lateral cephalometric radiography as a mean of diagnosing adenoids hypertrophy

INTRODUÇÃO: a hipertrofia de adenoide é uma das principais causas da respiração bucal. Entre os métodos utilizados para o diagnóstico dessa condição, os mais precisos são a endoscopia nasal e a ressonância magnética. No entanto, o método mais utilizado, em Odontologia, é a radiografia cefalométrica lateral. OBJETIVO: determinar a eficácia dessa radiografia no diagnóstico da hipertrofia de adenoide, pela sua comparação com a endoscopia nasal. MÉTODOS: foram avaliados 30 indivíduos (7 a 12 anos). Todos fizeram exame de endoscopia nasal e radiografia cefalométrica lateral. Nas endoscopias, foi registrada a porcentagem de obstrução da nasofaringe e, nas radiografias, a menor dimensão anteroposterior livre da nasofaringe. RESULTADOS: os exames se mostraram fortemente correlacionados (r = - 0,793, p-valor < 0,01). Considerou-se portadores de hipertrofia severa de adenoide os pacientes que apresentaram, na endoscopia, obstrução da nasofaringe igual ou superior a 75 por cento e, nas radiografias, o menor diâmetro anteroposterior da nasofaringe igual ou inferior a 5mm; o exame radiográfico teve uma sensibilidade de 75 por cento, especificidade de 86,3 por cento, valor preditivo positivo de 66,7 por cento, valor preditivo negativo de 90,4 por cento e exatidão de 83,3 por cento. CONCLUSÃO: a radiografia cefalométrica lateral se mostrou um exame eficiente para o diagnóstico da hipertrofia de adenoide.

INTRODUCTION: One of the most usual causes of mouth breathing is adenoids hypertrophy with reduction of the nasopharyngeal space. The most precise diagnostic methods are magnetic resonance and nasal endoscopy, because they make possible a three dimension image of the nasopharynx. However, in Dentistry, cephalometric radiography is the method used in the majority of cases. That is why it is so important the evaluation of the efficacy of this diagnostic method. AIM: The aim of this paper is to determine the efficacy of the lateral cephalometric radiography in diagnosing adenoids hypertrophy, comparing this method to the nasal endoscopy. METHODS: Thirty patients (7 to 12 years), with no history of otolaryngological surgery, were evaluated. All of them were submitted to a nasal endoscopy and a lateral cephalometric radiography. In the endoscopic exams it was registered the percentage of nasopharyngeal obstruction and in the radiographic exams it was registered the minor nasopharyngeal dimension. RESULTS: The results of the exams showed a strong correlation with each other (r = - 0.793, p-value < 0.01). After that, reliability tests to the radiographic diagnose were performed, assuming that 75 percent (endoscopic exams) and 5mm (radiographic exams) were the limit values to the determination of the diagnose of severe adenoids hypertrophy. The radiographic exam showed a sensibility of 75 percent, specificity of 86.3 percent, positive predictive value of 66.7 percent, negative predictive value of 90.4 percent and an exactness of 83.3 percent. Therefore, lateral cephalometric radiography is an efficient method of adenoids hypertrophy diagnose. It was proved by the strong correlation of its results with the results of the nasal endoscopy, that is considered a method of excellence for diagnosing this condition.

Spectroscopic analysis of works of art using a single LIBS and pulsed Raman setup.

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.

Analysis of natural and artificial ultramarine blue pigments using laser induced breakdown and pulsed Raman spectroscopy, statistical analysis and light microscopy.

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.

A study on the anisole-water complex by molecular beam-electronic spectroscopy and molecular mechanics calculations.

An experimental and theoretical study is made on the anisole-water complex. It is the first van der Waals complex studied by high resolution electronic spectroscopy in which the water is seen acting as an acid. Vibronically and rotationally resolved electronic spectroscopy experiments and molecular mechanics calculations are used to elucidate the structure of the complex in the ground and first electronic excited state. Some internal dynamics in the system is revealed by high resolution spectroscopy.

Characterisation of pigments and corrosion patinas by means of micro-Raman spectroscopy.

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.