Is There Any Difference Between a Spherical Marker and a Simple Coin for Hip Replacement Digital Planning? / Existe alguma diferença entre um marcador esférico e uma moeda simples para planejamento digital de substituição de quadril?

Abstract Objective To evaluate the accuracy and differences between 2 types of metallic markers, sphere, and coin, for radiographic calibration in the preoperative planning of hip arthroplasty. Methods Four spherical metallic markers and four coins, both 25 mm in diameter, were placed on the greater trochanter, pubic symphysis, between the thighs, and on the table of the exam, for radiographic examination of the hip in 33 patients with hip prosthesis. The prosthesis head was used for calibration and two examiners measured the markers' image diameters, and the results were analyzed statistically. Results In the greater trochanter, the sphere and the coin were not visualized in 19 radiographs (57.6%). Between the thighs, the coin marker was not visualized in 13 radiographs (39.4%). In the greater trochanter, the 25-mm accuracy of the coin and the sphere was, respectively, between 57.1 and 63.3% and between 64.3 and 92.9%. The coin between the thighs reached 25-mm accuracy in between 50 and 60% of cases. Over the exam table, the coin and sphere markers reached, respectively, the mean diameters of 22.91 mm and 23 mm, the lowest coefficient of variation, the lowest confidence interval, and the easiest positioning. There was statistical difference between the evaluations of the markers (coin vs. sphere) in all positions (p< 0.032), except for the exam table position (p= 0.083). Conclusions The coin between the thighs is the best marker for radiographic calibration in the preoperative planning of hip arthroplasty, and we suggest the use of another coin on the exam table for comparison, considering the 8% reduction in relation to its real size.

Resumo Objetivo Avaliar a precisão e as diferenças entre 2 tipos de marcadores metálicos, esfera e moeda, para calibração radiográfica no planejamento pré-operatório da artroplastia de quadril. Métodos Quatro marcadores metálicos esféricos e quatro moedas, ambas de 25 mm de diâmetro, foram colocadas em trocânter maior, sínfise púbica, entre as coxas e a mesa do exame, para exame radiográfico do quadril em 33 pacientes com prótese de quadril. A cabeça da prótese foi utilizada para calibração e dois examinadores mediram os diâmetros da imagem dos marcadores, e os resultados foram analisados estatisticamente. Resultados No trocânter maior, a esfera e a moeda não foram visualizadas em 19 radiografias (57,6%). Entre as coxas, o marcador de moeda não foi visualizado em 13 radiografias (39,4%). No trocânter maior, a precisão de 25 mm da moeda e da esfera foi, respectivamente, entre 57,1 e 63,3% e entre 64,3 e 92,9%. A moeda entre as coxas atingiu 25 mm de precisão entre 50 e 60%. Sobre a mesa de exame, os marcadores de moeda e esfera atingiram, respectivamente, diâmetros médios de 22,91 mm e 23 mm, o menor coeficiente de variação, o menor intervalo de confiança e o posicionamento mais fácil. Houve diferença estatística entre as avaliações dos marcadores (moeda vs. esfera) em todas as posições (p< 0,032), com exceção da posição na mesa de exame (p= 0,083). Conclusões A moeda entre as coxas é o melhor marcador para calibração radiográfica no planejamento pré-operatório da artroplastia de quadril, e sugerimos o uso de outra moeda na mesa de exame para comparação, considerando os 8% de redução em relação ao seu tamanho real.

Is it Important to Know Where to Place the Spherical Marker for Hip Replacement Digital Planning? / É importante saber onde posicionar o marcador esférico para o planejamento digital de artroplastia de quadril?

Abstract Objective The present paper aims to evaluate the influences of individual characteristics in radiographic magnification and to identify the most accurate method for radiographic calibration. Methods During radiographical exam of 50 patients with hip prosthesis, anthropometric data was collected and 4 spherical metal markers with 25 mm diameters were positioned: at the greater trochanter level and lateral to it, over the pubic symphysis, between the thighs at the greater trochanter level, and over the exam table. Since the prosthesis head is the best internal radiographic marker for hip arthroplasty, it was our calibration parameter. Two examiners measured the markers' image for further analysis. Results The sample consisted of 50 participants, 19 of whom were male. A difference in pubic symphysis magnification was found. Other individual characteristics (weight, height and body mass index) had weak correlation. The higher accuracy of the markers was at the greater trochanter, between 68.4 and 78.9%, visualized in only19 radiographs. The marker positioned between the thighs was visualized in all radiographs, with an accuracy ranging from 30 to 46%. Conclusions Of all individual characteristics, only gender influences magnification at the pubic symphysis. We suggest the use of two spherical markers: at the greater trochanter, due the best accuracy, and between the thighs, considered the best positioning for better visibility.

Resumo Objetivo Os objetivos desse artigo são avaliar as influências das características pessoais na magnificação radiográfica e identificar o método de maior acurácia e o mais adequado. Métodos Durante o exame radiográfico em 50 pacientes com prótese de quadril, foram coletados dados antropométricos e posicionados quatro marcadores metálicos esféricos: ao nível e lateral ao trocânter maior, na sínfise púbica, ao nível do trocânter maior entre as coxas, sobre a mesa do exame. A cabeça da prótese é o melhor marcador radiográfico interno e foi o nosso parâmetro de calibragem. Dois avaliadores mediram as imagens desses marcadores para análise de resultados. Resultados Foram selecionados 50 participantes, sendo 19 do sexo masculino. Houve diferença de magnificação entre os sexos na posição sínfise púbica. As outras características pessoais avaliadas (peso, altura e índice de massa corpórea) tiveram correlação fraca. A maior acurácia do marcador foi no trocânter maior, entre 68,4 e 78,9%, visualizado em apenas 19 radiografias. O marcador entre as coxas obteve acurácia entre 30 e 46% e foi visualizado em todas as radiografias. Conclusão Das características pessoais, apenas o sexo influencia a magnificação e somente na posição da sínfise púbica. Sugerimos padronizar o uso de duas esferas: no trocanter maior, pela maior acurácia, e entre as coxas, por ser o mais adequado e com melhor visibilidade em todas radiografias.

Comparison of Vertical Magnification Ratio among Various Areas in Panoramic Radiographs

PURPOSE: The objective of the present article is to determine whether there are differences in vertical enlargement ratio among various sites within both jaws in a panoramic radiograph. MATERIALS AND METHODS: Two hundred and seventy-threeimplant sites in panoramic radiographs were evaluated by two observers. Magnification ratios at various sites in both jaws were calculated and compared with each other. RESULT: The average vertical enlargement ratio in the panoramic radiograph was 1.264 and this value was larger than original ratio 1.250. Although vertical magnification ratio of maxillary molar area was higher than that of mandibular molar area, every group showed similar magnification ratio in clinical respect. CONCLUSION: Vertical magnification ratio of the maxillary molar area is statistically higher than that of the mandibular molar area in the panoramic radiograph, but it is clinically negligible.

Localización efectiva de un segundo conducto radicular en incisivos inferiores mediante magnificación, radiografía y diafanización / Effective location a second root canal in lower incisors by magnification radiography and diaphanization

Objetivo: Evaluar in vitro, la efectividad del método visual y radiográfico, comparándolos con la técnica de diafanización en la detección del segundo conducto radicular de incisivos inferiores tratados endodónticamente. Material y métodos: Fueron analizados 133 dientes incisivos inferiores permanentes, tratados endodónticamente, a través de métodos visuales (con y sin auxilio de magnificación), radiográficos y de diafanización. El análisis radiográfico fue realizado en negatoscopio utilizando una lupa estereoscópica (10X). Posteriormente, fue realizada la remoción completa de la obstrucción provisional para la exploración visual con y sin auxilio de microscopio clínico (MO) en un aumento de 12X. Finalmente los dientes fueron diafanizados y almacenados en salicilato de metila para posterior análisis. Dos evaluadores calibrados registraron los datos referentes a la presencia o no del segundo conducto radicular para cada uno de los métodos utilizados. Resultados: El análisis radiográfico mostró la presencia del segundo conducto en 24 dientes (18,05%. Visualmente, fue encontrado en 4 dientes (3,00%) sin magnificación y en 16 dientes (12,03%) con ayuda del MO. A través de la diafanización, 34 dientes (25,95%) presentaron segundo conducto. Conclusiones: La asociación de técnicas radiográficas y la magnificación visual obtenida con la utilización del MO se muestran como los aliados clínicos más efectivos para la localización del segundo conducto en incisivos inferiores.

Objective: To evaluate in vitro the effectiveness of the visual, radiographic and clearing technique on detection of two root canals in mandibular incisor teeth endodontically treated. Material and methods: One hundred thirty-three human permanent lower incisors were anlyzed through visual methods (with and without magnification), radiographic and clearing technique. Radiographic analysis was performed in light box using a stereomicroscope (10X). Then, the temporary filling of al specimens was removed for visual exploration with and without clinical microscope (OM) (12X). Finally the teeth were submitted to clearing technique and stored in methyl salicylate for subsequent analysis. Two calibrated reviewers recorded data about the presence or absence of the second root canal for each of the used methods. Results: Radiographic analysis showed the presence of the second root canal in 24 teeth (18.05%). Visually, it was found in 4 teeth (3.00%) and 16 teeth (12.03%) without and with the use of OM, respectively. Through clearing technique, in 334 teeth (25.95%) it was found the second root canal. Conclusion: The association of radiographic techniques and visual magnification with the use of MO has been shown as the most effective clinical partners to locate the second root canal in mandibular incisors.

Diagnóstico de infección por Helicobacter pylori en cuerpo gástrico con magnificación endoscópica y "flexible spectral imaging colour enhancement" (FICE) / Diagnosis of Helicobacter pylori infection in gastric body with endoscopic magnification and flexible spectral imaging colour enhancement (FICE)

La endoscopia estándar no diagnostica infección por Helicobacter pylori. Con magnificación y "Flexible Spectral Imaging Colour Enhancement" (FICE) se observan patrones de mucosa gástrica que sugieren su presencia. Diagnosticar infección por Helicobacter pylori con magnificación endoscópica y "Flexible Spectral Imaging Colour Enhancement" (FICE). Previo consentimiento se incluyeron a los individuos con indicación electiva de endoscopia digestiva superior. Se realizó endoscopia digestiva superior con equipo Fujinon Inc. EG 590 ZW, y procesador EPX 4400. En ambas caras del cuerpo gástrico se realizó consecutivamente: a) alta resolución, b) magnificación, c) alta resolución, d)FICE, e)magnificación y f) biopsia en el antro y del patrón mas prevalente en cada cara del cuerpo evaluadas sin información del paciente. Todo el procedimiento se grabó, se fotografió y se guardó en JPEG en programa Power Point. Se evaluaron 60 áreas en 30 pacientes: 10 hombres y 20 mujeres con edades de 20-82 años y promedio 49,60 años. Solo magnificación y FICE identificaron los patrones de mucosa en cuerpo gástrico. En 37,03% se diagnosticó Helicobacter pylori con histología, 53,33% y 61,11% en patrón Z2 y Z3 respectivamente. La magnificación y FICE permiten identificar los patrones de mucosa gástrica que sugieren infección por Helicobacter pylori

Helicobacter pylori infection is not diagnosed with standard endoscopy. With high resolution and magnification patterns of gastric mucosa suggesting its presence are observed. Diagnose Helicobacter pylori infection with endoscopic magnification and "Flexible Spectral Imaging Colour Enhancement" (FICE). Individuals scheduled to undergo routine upper gastrointestinal endoscopy were enrolled. Upper gastrointestinal endoscopy was performed with Fujinon Inc. 590 EG ZW and EPX 4400 processor. Endoscopy was practiced on both sides of the gastric body consecutively with: a) high-resolution, b) magnification, c) high-resolution, d) FICE, e) magnification and g) biopsy of the antrum and the pattern more prevalent on each side of the body evaluated without patient information. The entire procedure was recorded, was photographed and was saved in JPEG in program Power Point. 60 Areas in 30 patients were evaluated: 10 men and 20 women with ages of 20-82 years and average 49.60. Only magnification and FICE identified patterns of mucosa in gastric body. Helicobacter pylori was diagnosed in 37.03% with histology and in pattern Z2 and Z3 in 53.33% and 61.11% respectively. The endoscopic magnification and Flexible Spectral Imaging Colour Enhancement (FICE) identify patterns of gastric mucosa suggesting Helicobacter pylori infection

Evaluation of vertical magnification of panoramic radiography by CT scan sections for dental implant

The Panoramic radiography is one of the routine techniques in implant imaging. Although there are some limitations with this technique, panoramic radiography is radiographic choice for basic evaluation for implant treatment. Many studies have been designed to determine magnification in panoramic images but most of them were performed on dry skulls or radiographic phantoms. In recent studies CT or CBCT are used as gold standard. The aim of this study was to determine vertical magnification of panoramic images using renovated CT sections in anterior and posterior regions of both jaws. 30 panoramic radiographs [Planmeca EC or CC Proline] were selected from patients of implant department and Particular anatomic landmarks were selected in those images. Vertical dimensions of these landmarks were measured in both panoramic and renovated cross sectional CT images by a digital caliper and vertical magnification was calculated as the ratio of image dimensions to the real dimensions. The mean vertical magnification of panoramic radiographs in anterior and posterior maxillae were 1.22 +/- 0.02 and 1.16 +/- 0.02, respectively. The mean vertical magnification of panoramic radiograph in anterior and posterior mandible were 1.20 +/- 0.02 and 1.13 +/- 0.02, respectively. The differences between magnification in mandible and maxillae were significant [P<0.001]. The differences between magnification in anterior and posterior regions of both jaws were not significant [P=0.11]. Vertical magnification of panoramic images [Planmeca EC or CC Proline] in different regions in both jaws were between 1.13 to 1.22

Los anti-TNF y la progresión radiográfica en espondilitis anquilosante / The anti-TNF and the radiological progression in ankylosing spondylitis

Los agentes biológicos inhibidores del factor de necrosis tumoral alfa (anti-TNF) se constituyen en un avance muy significativo en el tratamiento de los pacientes con espondilitis anquilosante (EA), demostrando una notable mejoría de sus síntomas, de su función y de su calidad de vida. Sumado a esta excelente respuesta clínica, se ha demostrado igualmente mejoría de la inflamación, demostrada mediante pruebas de laboratorio y estudios de resonancia nuclear magnética. A pesar de esta clara evidencia, la conexión entre actividad inflamatoria y progresión estructural no está tan claramente establecida como en artritis reumatoide (AR), y la evidencia de la eficacia de los anti-TNF en la prevención de la progresión del daño radiológico crónico en EA es deficiente. Se revisan las evidencias y las teorías actuales respecto a este crucial tema y se hace mención del importante papel de la proteína DKK-1, inhibidora de la vía Wnt. Esta proteína ha emergido recientemente como un regulador fundamental en la biología ósea y se constituye en una conexión clave entre inflamación, osteoporosis y remodelación articular.

The anti-TNF biological agents constitute a major advance in the treatment of patients with ankylosing spondylitis (AS) showing a remarkable improvement in symptoms of patients, their function and quality of life. In addition to this excellent clinical response, it has also been clearly demonstrated improvement of inflammation as evidenced by laboratory tests and MRI studies. Despite this clear evidence, the connection between inflammatory activity and structural progression is not as clearly established as in rheumatoid arthritis, and the evidence of anti-TNF therapy to prevent chronic EA radiological damage is poor. We review the evidence and current theories about this crucial issue and mention the important role of DKK-1 protein, an inhibitor of the Wnt pathway. This protein has recently emerged as a key regulator in bone biology and constitutes a key link between inflammation, osteoporosis and joint remodeling.

In vitro study on radiographic gray levels of biomaterials using two digital image methods / Estudo in vitro dos níveis radiográficos de cinza de biomateriais utilizando duas modalidades de imagem digital

PURPOSE: To compare the direct and indirect radiographic methods for assessing the gray levels of biomaterials employing the Digora for Windows and the Adobe Photoshop CS2 systems. METHODS: Specimens of biomaterials were made following manusfacturer's instructions and placed on phosphor storage plates (PSP) and on radiographic film for subsequent gray level assessment using the direct and indirect radiographic method, respectively. The radiographic density of each biomaterial was analyzed using Adobe Photoshop CS2 and Digora for Windows software. RESULTS: The distribution of gray levels found using the direct and indirect methods suggests that higher exposure times are correlated to lower reproducibility rates between groups. CONCLUSION: The indirect method is a feasible alternative to the direct method in assessing the radiographic gray levels of biomaterials, insofar as significant reproducibility was observed between groups for the exposure times of 0.2 to 0.5 seconds.

OBJETIVO: Comparar os métodos radiográficos direto e indireto para avaliar os níveis de cinza de biomateriais empregando os sistemas Digora for Windows e Adobe Photoshop CS2. MÉTODOS: corpos de prova confeccionados com biomateriais foram posicionados numa película radiográfica e numa placa de fósforo com protetor para a realização de exposições radiográficas e posterior avaliação dos níveis de cinza por meio dos métodos indireto e direto, respectivamente. A densidade radiográfica de cada biomaterial foi analisada usando-se os sistemas Adobe Photoshop CS2 e Digora for Windows. RESULTADOS: A distribuição de níveis de cinza observada por meio dos métodos direto e indireto sugeriu uma menor reprodutibilidade entre grupos quanto maior o tempo de exposição. CONCLUSÃO: O método indireto constitui uma alternativa viável ao método direto para avaliar os níveis radiográficos de cinza de biomateriais na medida em que foi observada uma reprodutibilidade significativa entre grupos nos tempos de exposição de 0,2 a 0,5 segundos.

Diagnóstico de las lesiones neoplásicas y no-neoplásicas y predicción de la invasión submucosa del cáncer colorrectal temprano durante la colonoscopia / Diagnosis of neoplastic and non-neoplastic lesions and prediction of submucosal invasion of early cancer during colonoscopy

La cromoendoscopia de magnificación es una nueva y atractiva herramienta que permite un análisis detallado de la arquitectura morfológica de los orificios de las criptas de la mucosa. En esta revisión describimos, principalmente, la eficacia de la cromoendoscopia de magnificación y de la colonoscopia de magnificación con NBI para el diagnóstico diferencial de las lesiones colorrectales, incluyendo una distinción entre lesiones neoplásicas y no-neoplásicas y también entre cáncer temprano tratable endoscópicamente o no, basados en una revisión de la literatura. Hemos conducido un estudio prospectivo mostrando que una combinación de la colonoscopia de magnificación y la cromoendoscopia es actualmente un método más confiable que la colonoscopia convencional y la cromoendoscopia para la distinción entre lesiones neoplásicas y no-neoplásicas del colon y del recto. La colonoscopia de magnificación con NBI es tan precisa como la cromoendoscopia de magnificación. Nosotros utilizamos colonoscopia de magnificación con NBI más que la cromoendoscopia para distinguir de rutina los pólipos neoplásicos de los no-neoplásicos. Los colonoscopistas pueden predecir la profundidad de la invasión del cáncer colorrectal por medio de la cromoendoscopia de magnificación, la colonoscopia de magnificación con NBI y a través del signo de no-levantamiento. Entre estos métodos, la cromoendocopia de magnificación es el más confiable, con una exactitud, sensibilidad y especificidad de 98,8%, 85,6% y 99,4%, respectivamente. Aunque su confiabilidad depende de la habilidad del que hace la observación, la difusión de las aplicaciones de la técnica de magnificación podría influir en las indicaciones de biopsias de muestreo durante la colonoscopia y en las de mucosectomía.

Magnifying chromoendoscopy is an exciting new tool that allows detailed analysis of the morphological architecture of mucosal crypt orifices. In this review, we principally describe the efficacy of magnifying chromoendoscopy and magnifying colonoscopy with narrow band imaging (NBI) for differential diagnosis of colorectal lesions, including distinction between non-neoplastic and neoplastic lesions, and also between endoscopically treatable early invasive cancers and untreatable cancers, based on a review of the literature. We have conducted a prospective study showing that a combination of magnifying colonoscopy and chromoendoscopy is currently a more reliable method than conventional endoscopy and chromoendoscopy for separating non-neoplastic from neoplastic lesions of the colon and rectum. Magnifying colonoscopy with NBI is convenient and as accurate as chromoendoscopy with magnification. We principally use only magnifying colonoscopy with NBI, rather than chromoendoscopy, to routinely distinguish neoplastic from non-neoplastic polyps. Colonoscopists can predict the depth of invasion of early colorectal cancer by magnifying chromoendoscopy, magnifying colonoscopy with NBI and the non-lifting sign. Among these approaches, magnifying chromoendoscopy is diagnostically the most reliable, with an accuracy, sensitivity, and specificitiy of 98.8%, 85.6%, and 99.4%, respectively. Although its reliability depends on the skill of magnifying observation, widespread applications of the magnification technique could influence the indications for biopsy sampling during colonoscopy and the indications for mucosectomy.

Predicting the actual length of premolar teeth on the basis of panoramic radiology.

Background: Panoramic radiography is one of the most common techniques for evaluating the jaw bones and associated structures. Aim: The aim of the study was to predict the actual length of the premolar teeth, based on measurements taken on a panoramic radiograph. Materials and Methods: This study was done in two stages. In the first stage, the actual and panoramic lengths of 102 teeth of orthodontic patients were measured and compared. In the next stage, the actual and radiographic vertical lengths of four metal balls placed in the molar and first premolar areas of 27 patients, referred to radiography clinic were also analyzed. Comparison of the mean magnification between the two methods was performed by one-sample T-test and P<0.05 was considered as statistically significant. Results: The total magnification of the premolar region in the vertical plane in the tooth length measurement method was 17.39%, while the same in the metal markers method was 27.39%. The upper teeth showed larger magnification than the lower teeth in the vertical plane. Similarly, the magnification and distortion of the metal markers in the horizontal plane were significantly more than this in the vertical plane and also their magnification and distortion in the molar region were more than this in the premolar region. The actual length of the premolar teeth can be estimated by using a suitable regression formula. Conclusion: Panoramic radiography can be used for calculating the actual length of premolar teeth.

Evaluation of the panoramic image formation in different anatomic positions

The aim of this study was to determine size, shape and position of the image layer by evaluation of the radiographic image formation in different anatomic positions. A customized phantom was made of a rectangular acrylic plate measuring 14 cm² and 0.3 cm thick, with holes spaced 0.5 cm away and arranged in rows and columns. Each column was separately filled with 0.315 cm diameter metal spheres to acquire panoramic radiographs using the Orthopantomograph OP 100 unit. The customized phantom was placed on the mental support of the device, with its top surface kept parallel to the horizontal plane, and was radiographed at three different heights from the horizontal plane, i.e., the orbital, occlusal and mandibular symphysis levels. The images of the spheres were measured using a digital caliper to locate the image layer. The recorded data were analyzed statistically by the Student'-t test, ANOVA and Tukey' test (?=0.05). When the image size of spheres in horizontal and vertical axes were compared, statistically significant differences (p<0.05) were observed in all areas, portions of the image layer and heights of horizontal plane evaluated. In the middle portion of the image layer, differences in the image size of spheres were observed only along the horizontal axis (p<0.05), whereas no differences were observed along the vertical axis (p>0.05). The methodology used in this determined the precise size, shape and position of the image layer and differences in magnification were observed in both the horizontal and vertical axes.

O objetivo na presente pesquisa foi determinar o tamanho, forma e posição da camada de imagem por meio da avaliação da formação da imagem radiográfica em diferentes posições anatômicas. Foi construído um phantom constituído por uma placa acrílica de 14 cm² e 0,3 cm de espessura, com sua superfície contendo perfurações a cada 0,5 cm dispostas em linhas e colunas. O phantom foi posicionado no local do apoio de mento do aparelho panorâmico, com sua superfície paralela ao plano horizontal. Esferas metálicas de 0,315 cm foram inseridas nas perfurações, e executadas radiografias panorâmicas. Cada coluna de cada quadrante foi individualmente preenchida pelas esferas para a execução das radiografias, em três planos horizontais diferentes: alturas orbital, oclusal e mentual. As imagens das esferas foram medidas com o uso de um paquímetro digital e a camada de imagem localizada. Os dados foram analisados estatisticamente utilizando-se o teste T Student, ANOVA e teste de Tukey (?=0,05). Quando o tamanho das esferas nos eixos horizontal e vertical foi comparado, diferenças estatisticamente significativas (p<0,05) foram observadas em todas as áreas da camada de imagem, porções e alturas do plano horizontal avaliado. Na porção central da camada de imagem diferenças no tamanho das esferas foram observadas somente no eixo horizontal (p<0,05), enquanto que no eixo vertical nenhuma diferença foi observada (p>0,05). A metodologia utilizada determinou com precisão o tamanho, forma e posição da camada de imagem, e diferenças de ampliação foram observadas tanto no eixo horizontal quanto vertical.

A medição da grandeza practical peak voltage na prática radiológica / Measurement of the quantity practical peak voltage in the radiology practice

OBJETIVO: O objetivo deste trabalho foi estudar a grandeza practical peak voltage (PPV), determinada a partir da forma de onda de tensão aplicada a tubos radiológicos, e compará-la com algumas definições de kVp para diferentes tipos de geradores: monofásico (onda completa, clínico), trifásico (seis pulsos, clínico) e potencial constante (industrial). MATERIAIS E MÉTODOS: O trabalho envolveu a comparação do PPV medido invasivamente (utilizando um divisor de tensão) com a resposta de dois medidores comerciais não invasivos, além dos valores de outras grandezas usadas para medição da tensão de pico aplicada ao tubo de raios X, e a análise da variação do PPV com a ondulação percentual da tensão (ripple). RESULTADOS: Verificou-se que a diferença entre o PPV e as definições mais comuns de tensão de pico aumenta com o ripple. Os valores de PPV variaram em até 3 por cento e 5 por cento, respectivamente, na comparação entre medições invasivas e não invasivas feitas com os equipamentos trifásico e monofásico. CONCLUSÃO: Os resultados demonstraram que a principal grandeza de influência que afeta o PPV é o ripple da tensão. Adicionalmente, valores de PPV obtidos com medidores não invasivos devem ser avaliados considerando que eles dependem da taxa de aquisição e da forma de onda adquirida pelo instrumento.

OBJECTIVE: The present study was aimed at evaluating the practical peak voltage (PPV) determined from the voltage waveform applied to x-ray tubes and comparing it with some kVp definitions for different types of x-ray equipment: single-phase (full-wave) and three-phase (six-pulse) clinical x-ray generators, and an industrial constant potential apparatus. MATERIALS AND METHODS: The study involved the comparison between invasively measured PPV (with voltage dividers) and values obtained with two commercial noninvasive meters, besides values of other quantities utilized for measuring the x-ray tube peak voltage. The PPV variation with the voltage ripple was also analyzed in the present study. RESULTS: The authors observed that the difference between PPV and the most common peak voltage definitions increases with the ripple. PPV values varied up to 3 percent and 5 percent, respectively, in the comparison between invasive and non-invasive measurements with single-phase and three-phase devices. CONCLUSION: The results demonstrated that voltage ripple is the main quantity influencing the invasive or non-invasive PPV determination. Additionally, non-invasively measured PPV values should be evaluated taking into consideration their dependence on the data sample rate and waveform obtained by the device.

Comparación de la endoscopia de alta resolución con magnificación y fice y la endoscopia de alta resolución en el diagnóstico de enfermedad de reflujo erosiva / Comparison of high resolution endoscopy and magnification endoscopy fice and high resolution in the diagnosis of erosive reflux disease

La enfermedad por reflujo gastroesofágico es una enfermedad crónica del esófago, su diagnóstico clínico está basado en sus síntomas, pero la endoscopia determina dos entidades clínicas. El 50 por ciento de los pacientes con enfermedad por reflujo gastroesofágico tienen enfermedad por reflujo gastroesofágico y esofagitis. El objetivo de este trabajo es demostrar que la endoscopia de alta resolución con magnificación y Fuji intelligent color enhancement, tienen un mayor porcentaje diagnóstico de enfermedad por reflujo gastroesofágico, tienen enfermedad por reflujo gastroesofágico y esofagitis cuando se compara con la endoscopia de alta resolución. Materiales y métodos: Se realizó endoscopia de alta resolución y endoscopia de alta resolución con magnificación y Fuji intelligent color enhancement a 50 pacientes con el diagnóstico clínico de enfermedad por reflujo gastroesofágico. Se comparó con un grupo control de 50 pacientes. Resultados: La endoscopia de alta resolución dio un 70 por ciento de diagnóstico de enfermedad por reflujo gastroesofágico tienen enfermedad por reflujo gastroesofágico y esofagitis y la endoscopia de alta resolución con magnificación y fuji intelligent color enhancement dio un 98 por ciento de diagnóstico de enfermedad por reflujo gastroesofágico tienen enfermedad por reflujo gastroesofágico y esofagitis (P=0,0002), estadísticamente significativa. Conclusión: La endoscopia de alta resolución con magnificación y fuji intelligent color enhancement, es el método endoscópico de elección, para diagnosticar la existencia de enfermedad por reflujo gastroesofágico tienen enfermedad por reflujo gastroesofágico y esofagitis, en los pacientes con diagnóstico clínico de enfermedad por reflujo gastroesofágico

The gastroesophageal reflux disease (GERD) is a chronic illness of the esophagus, where the clinical diagnosis is based on their symptoms, but the Endoscopy determines two clinical entities. 50 percent of the patients with gastroesophageal reflux disease has esophagitis. The Objective of this trial was demonstrate that the High Resolution Endoscopy with Magnification and Fuji Intelligent Color Enhancement (FICE) had a major percentage diagnosis of ERGEE, when it was compared with the High Resolution Endoscopy. Materials and Methods: It was performed High Resolution Endoscopy and High Resolution Endoscopy with Magnification and Fuji intelligent color enhancement to 50 patients with the clinical diagnosis of gastroesophageal reflux disease, and it was compared with a control group of 50 patients. Results: The high resolution endoscopy demonstrated 70 percent of diagnosis of gastroesophageal reflux disease has esophagitis and the high resolution endoscopy with magnification and Fuji intelligent color enhancement reported 98 percent of diagnosis of gastroesophageal reflux disease has esophagitis (P=0.0002), statistically significant. There was not significant statistical difference in the control group. Conclusion: The high resolution endoscopy with magnification and Fuji intelligent color enhancement was the method of choice to evaluate the existence of gastroesophageal reflux disease has esophagitis, in patients with clinical diagnosis of gastroesophageal reflux disease

Image quality in partially erased DenOptix® storage phosphor plates

This study aimed at investigating the effect of the partial erasing of DenOptix® system storage phosphor plates on the image quality of digital radiographs. Standardized digital radiographs were acquired of a phantom mandible, using size 2 intraoral DenOptix® storage phosphor plates (n = 10). Subsequently, the active areas of the plates were placed in a viewing box with a constant light intensity of 1,700 lux for 130 seconds to achieve complete erasing (control plate), as well as for 0, 5, 10, 15, 20, 25, 34, 66, and 98 seconds, to compose the experimental group of partially erased plates. The same exposure settings were repeated using the control and experimental plates, which were scanned at a resolution of 300 dpi. Five radiologists independently examined the pairs of digital radiographs obtained with the control and partially erased plates, in random order, and indicated the best image for oral diagnosis. Cochran-Mantel-Haenszel’s chi-square test, at a significance level of 5 percent, was used to compare the percentages of superior quality images in each combination of control and partially erased plates, subjectively assessed. No significant differences were found between radiographic images acquired with control and partially erased plates, except for the combination of 0 second (30 percent) versus 130 seconds (70 percent), p = 0.0047. It can be concluded that, under adequate light intensity conditions, erasing intraoral DenOptix® storage phosphor plates may require time intervals of as little as 5 seconds.

Avaliação da ampliação da imagem obtida em quatro aparelhos panorâmicos / Evaluation of image magnification of four panoramic machines

Este estudo avaliou a ampliação de imagens obtidas em quatro aparelhos panorâmicos. Foram radiografados crânios secos, desdentados, com marcadores metálicos na crista óssea nas regiões correspondentes ao incisivo central, canino, pré-molar e molar, superiores e inferiores. Nas imagens, obteve-se a dimensão vertical das esferas com paquímetro, com o qual se calculou as ampliações das regiões, que foram comparadas com a fornecida pelo fabricante, por análise estatística. Na maioria dos aparelhos, houve ampliações diferentes das fornecidas pelos fabricantes, que variaram de acordo com a região.

[ comparison of accuracy of determining the root canal working length by different magnifications of digital radiography]

Successful root canal therapy is related to cleaning, shaping and obturation of the root canal system with a proper limited working length. Therefore, these are achieved by knowledge of root canal anatomy and radiograph images. Current radiographic techniques are elementory methods. With the advancement of computer technology, and due to limitations that exist, in this recent decade significant attention has been given to digital radiography. Software programs for digital radiographic systems, such as magnification of different images is a tool assistant for digital systems in increasing precision. The purpose of this study was to compare different magnifications of digital radiography to determining canal length. In this experimental in vitro study, 30 human anterior teeth were selected and cleaned in detergent. The actual working length was measured with a N.15 file. Then the teeth were casted and the files were inserted in canals in 3 different positions, proper, under and over. Ninety images of the teeth in three magnifications were made and working length was evaluated by three endodontists randomly. Then the Friedman test was used for statistical analysis. After statistical analysis, the results showed that there was no significant differences between the groups. But there is significant difference in 2X magnificantion of under working length to real working length. In conclusion, it can be stated that magnification of digital radiography can not be helpful in determination of working length especially in under position

Avaliação da precisão da imagem radiográfica obtida com o uso de diferentes posicionadores / Evaluation of the radiographyc image precision using different film holders

O objetivo neste estudo foi comparar a precisão das imagens radiográficas realizadas com posicionadores de três diferentes marcas: Rinn XCP utilizando localizador curto e longo, Hanshin e lndusbello com localizador curto. As médias das medidas radiográficas foram calculadas e comparadas com o tamanho original dos dentes. Os resultados foram submetidos à análise de variância e ao teste de Tukey com a=0,05. Todos os posicionadores analisados ampliaram o tamanho da imagem sendo que o da Rinn XCP com localizador longo promoveu a menor ampliação. Não houve diferença estatisticamente significativa entre Rinn XCP com localizador longo e Hanshin. Os posicionadores da técnica da bissetriz e do paralelismo, quando utilizados com as distâncias recomendadas, possibilitaram a obtenção de mensurações dentárias próximas ao tamanho real.

The objective with this work was to compare the radiographic images precision of the dental elements accomplished with film holders of three different brand: RINN XCP used short and long beam-indicating devices, HANSHIN and INDUSBELLO used short beam-indicating devices. The mean measurements of radiographic image were calculated and compared with the teeth length size. All the film holders analyzed promoted the magnified radiographic and the RINN XCP's film holders with long beam indicating device promoted the minor magnified. No significant differences were found among RINN XCP's film holders with long beam-indicating device and HANSHIN. The film holders for the parallel and bisecting-the-angle technique when used with the recommended distances make possible to obtain radiographic image measurements close tooth length size.

Tomografía espiral convencional para implantes dentales: grado de magnificación / Conventional spiral tomohraphy for dental impants. Magnification degree

El propósito fue evaluar el grado de magnificación de la imagen obtenida en la tomografía espiral convencional en relación con las dimensiones óseas mandibulares reales. Se seleccionaron diez mandíbulas, las cuales fueron evaluadas mediante tomografía espiral convencional (Cranex TOME multifuncional unit). Seis observadores calificados realizaron mediciones en tres momentos diferentes de las mandíbulas y tomografías. Se utilizó el test de Levene para evaluar la homogeneidad de varianza entre las muestras. El grado de magnificación se evaluó con ANOVA (p=0.05). El test de Levene demostró que los valores de la muestra eran homogéneos y estadísticamente significativos (p>0.05). El rango de magnificación encontrado fue de 54.85 por ciento a 57.92 por ciento. En conclusión, el sistema de tomografía espiral convencional es adecuado para la evaluación y planificación de las estructuras óseas que van a recibir implantes dentales, considerando el porcentaje de magnificación encontrado.

Alteraciones del esmalte dental después de repetidos procesos de cementación de brackets ortodónticos: estudio in vitro / Enamel surface alterations after repeated processes of bonding orthodontic brackets: an in vitro study

Antecedentes: el estudio de las alteraciones en el esmalte dental de pacientes sometidos a tratamientos de ortodoncia, es de gran interés en el ámbito odontológico por la fijación de aparatología al esmalte; ello incluye las técnicas de cementación y la descementación, lo que puede resultar agresivo para la estructura de este tejido. Objetivo: el objetivo de este estudio descriptivo in vitro fue examinar la estructura superficial del esmalte dental después de haberse sometido a repetidos procesos de cementación de brackets ortodónticos, y evaluar los cambios que se producen, por medio de microscopía electrónica de barrido. Métodos: se tomaron 40 premolares sanos y sin tratamiento ortodóntico previo, que requerían extracción terapéutica, los cuales se mantuvieron en saliva artificial. La estructura superficial del esmalte se sometió a magnificación para descartar posibles daños durante el proceso de exodoncia. Se realizó profilaxis previa y se procedió a dividir los dientes en 4 grupos de 10 cada uno: grupo I o grupo control, y grupos II, III y IV con uno, dos y tres procesos de cementación y descementación, respectivamente. La evaluación se hizo analizando las fotografías obtenidas por MEB; se observó la presencia o ausencia de alteraciones de la superficie del esmalte, tales como rasgaduras, grietas y fracturas. Los datos fueron analizados con estadísticas descriptivas y la prueva del Chi2. Resultados: se obtuvo que a mayor cantidad de procesos de cementacion de brackets, mayor fue el deterioro de la superficie del esmalte dental. Conclusiones: se sugiere que el deterioro de la superficie del esmalte dentario se incrementa con el número de procesos de cementación