Diagnostic Performance of Digital Radiograph and Low-Dose Computed Tomography for the Diagnosis of Fishbone Retention in the Oropharynx

Abstract Introduction Fishbone foreign body retention is one of the most common problem with various clinical manifestations from asymptomatic, abscess formation, and perforation to mediastinitis with subsequence morbidity and mortality. Accurately identifying the location of the fishbone leads to precise removal, which, in turn, prevents serious consequences. Digital radiographs have been widely used for diagnosis, but many studies show poor sensitivity. Object The present study was designed to compare the diagnostic performances of digital radiograph and low-dose computed tomography (CT) for fishbone retention and to demonstrate the radiation dose of the two modalities. Methods We collected 2 pieces of fishbone from each of the 15 species commonly eaten in Southeast Asia. We embedded each fishbone in a fresh pig's neck, then subjected the pig's neck to lateral soft tissue neck digital radiograph. The locations to embed included tonsil, base of tongue, and upper esophagus. Then, we subjected the same specimen to a CT scan. Two experienced radiologists interpreted each image. Results Visibility in the digital radiograph group was 13%, and in CT images group, it was 87% regardless of the locations. The average radiation dose from digital radiographs was 0.4 mGy (radiation dose field), while from CT images it was 8.6 mGy (CT dose index). Conclusion Most of the common fishbones in Southeast Asia could not be visualized by digital radiograph when embedded in the neck. Computed tomography scans demonstrated better diagnostic performance of fishbone retention compared to digital radiographs, regardless of the embedded location.

Digital orthodontic radiographic set versus cone-beam computed tomography: an evaluation of the effective dose

ABSTRACT Objective: The aim of this study was to compare the equivalent and effective doses of different digital radiographic methods (panoramic, lateral cephalometric and periapical) with cone-beam computed tomography (CBCT). Methods: Precalibrated thermoluminescent dosimeters were placed at 24 locations in an anthropomorphic phantom (Alderson Rando Phantom, Alderson Research Laboratories, New York, NY, USA), representing a medium sized adult. The following devices were tested: Heliodent Plus (Sirona Dental Systems, Bernsheim, Germany), Orthophos XG 5 (Sirona Dental Systems, Bernsheim, Germany) and i-CAT (Imaging Sciences International, Hatfield, PA, USA). The equivalent doses and effective doses were calculated considering the recommendations of the International Commission of Radiological Protection (ICRP) issued in 1990 and 2007. Results: Although the effective dose of the radiographic set corresponded to 17.5% (ICRP 1990) and 47.2% (ICRP 2007) of the CBCT dose, the equivalent doses of skin, bone surface and muscle obtained by the radiographic set were higher when compared to CBCT. However, in some areas, the radiation produced by the orthodontic set was higher due to the complete periapical examination. Conclusion: Considering the optimization principle of radiation protection, i-CAT tomography should be used only in specific and justified circumstances. Additionally, following the ALARA principle, single periapical radiographies covering restricted areas are more suitable than the complete periapical examination.

RESUMO Objetivo: o objetivo deste estudo foi comparar as doses equivalentes e efetivas absorvidas pelo mesmo receptor, quando exposto a diferentes exames radiográficos digitais (panorâmica, telerradiografia lateral e periapicais) e à tomografia computadorizada de feixe cônico (TCFC). Métodos: dosímetros termoluminescentes pré-calibrados foram colocados em 24 locais em um phantom antropomórfico (Alderson Rando Phantom, Laboratórios de Pesquisas de Alderson, New York, NY, EUA), o que representa um adulto de tamanho médio. Os seguintes equipamentos foram avaliados: Heliodent Plus (Sirona Dental Systems, Bernsheim, Alemanha), Orthophos XG 5 (Sirona Dental Systems, Bernsheim, Alemanha) e i-CAT (Imaging Sciences International, Hatfield, PA, EUA). As doses equivalentes e as doses efetivas foram calculadas tendo-se em conta as recomendações da Comissão Internacional de Proteção Radiológica (International Commission on Radiological Protection, ICRP), publicadas em 1990 e 2007. Resultados: embora a dose eficaz do set radiográfico tenha correspondido a 17,5% (ICRP 1990) e 47,2% (ICRP 2007) da dose da TCFC, as doses equivalentes na pele e superfícies ósseas e musculares desse set foram maiores, quando comparadas às da TCFC. Em algumas áreas, a radiação produzida pelo set de radiografias foi maior, devido à radiação do exame periapical completo. Conclusão: considerando-se o princípio da otimização da proteção radiológica, a tomografia computadorizada adquirida no tomógrafo i-CAT deve ser usada apenas em circunstâncias específicas e justificadas. Além disso, seguindo o princípio ALARA, radiografias periapicais unitárias de áreas pré-selecionadas são mais apropriadas do que o exame periapical completo.

Image adjustments on digital panoramic radiographs using Adobe Photoshop CS3 software

Introduction: Favourable manipulation of images may be the greatest advantage of the digital radiographic compared to the conventional film. The current development of the cost-benefit of intra- and extraoral digital technology, besides the increase of computerized practices has turned the digital image into a superior alternative to conventional radiographs, in several aspects. Objective: To demonstrate image adjustments on digital panoramic radiographs using Adobe Photoshop CS3 ( Creative Suite 3) software in order to enhance digital images. Case reports: Digital treatment was conducted in two different cases using two filters available in Adobe Photoshop CS3: Smart Sharpen and Unsharp-Mask. Both filters improve overall image quality. In the second case, after brightness and contrast adjustments, it was possible to have a detailed visualization of radiopaque and radiolucent areas. Conclusion: The application of brightness and contrast adjustments and filters are feasible methods in order to achieve diagnostic precision.

Digital radiographic evaluation of the midpalatal suture in patients submitted to rapid maxillary expansion.

Aims: To analyze the density of the midpalatal suture by means of digital radiographs three months after retention to evaluate if this period of retention is really sufficient for bone repair. Materials and Methods: This prospective study consisted of 31 patients (11 girls and 20 boys) in the mixed or permanent dentition stage, treated using a tooth-tissue borne expanders (Haas). Occlusal digital radiographs were taken at three stages: prior to rapid maxillary expansion (Stage I); immediately after desired maxillary expansion (Stage II); and after three months of retention (Stage III). Radiographs were taken on a dental X-ray machine, set at 70 kVp and 7 mA with an exposure time of 0.04 s. A phosphor storage plate system, imaging plate size n. 2 (35 × 45 × 1.6 mm), was used. Three regions (A, B and C) measured 0.02 mm² were selected for optical density analysis. The difference between the measurements was evaluated with the paired t-test. Results: The optical density was reduced at Stages II and III compared with Stage I. Between-stage comparison showed statistically significant changes for all variables (P < 0.05), with the highest mean optical density at Stage I and the lowest at Stage II, in all groups. Actually, there was an increase in optical density between Stages II and III, but they are reduced compared with Stage I. Conclusion: The results strongly suggest that bone formation did not occur as expected, and that a longer retention period for bone repair may be necessary.

Digital radiograph of the middle phalanx of the third finger (MP3) region as a tool for skeletal maturity assessment.

Objective: To evaluate the reliability of the digital radiograph of the middle phalanx of the third finger (MP3) in skeletal maturity assessment Study Design: Fifty children (24 girls and 26 boys) belonging to the circumpubertal age-group were selected for the study. Two radiographs - lateral cephalogram and digital radiograph of the MP3 region - were taken in each child. Age assessment was based on the changes in shape of the cervical vertebrae and the epiphysis of the middle phalanx of the third finger of the left hand. The radiographs were assessed by three examiners. The inter- and intraexaminer variability were determined by the Wilcoxon rank sign test and the Kruskal-Wallis test and were found to be nonsignificant. Examiner 3 showed the best intraexaminer agreement and was selected to evaluate the radiographs for the entire study. Results: The correlation determined between the MP3 stages and cervical vertebrae maturity index (CVMI) stages, the peak-wise distribution of the MP3 stages, and the correlation between the MP3 stages and the chronological age were found to be highly significant. Conclusions: Digital radiograph of the MP3 region is definitely a simple, reliable, cost-effective, and time-saving technique for the assessment of skeletal maturity.

Reliability of the Radiologic Measurement Methods for Assessment of Osteoporosis Using the Digital Hip Radiograph

PURPOSE: We evaluated the usefulness of radiographic parameters for osteoporosis by analyzing the results of radiographic parameters determined by digital hip radiographs and bone mineral density T-scores, as assessed by Dual Energy X-ray Absorptiometry (DEXA). MATERIALS AND METHODS: The authors reviewed 100 subjects in the hip fracture group and 50 in the non-fracture control group. Digital hip radiographs were assessed to determine the values of Singh index, Canal-to-Calcar Ratio, and Cortical Thickness Index (CTI). Bone mineral density was assessed by DEXA. RESULTS: Intraclass Correlation Coefficient (ICC) results of the CTI were above 0.8 in the fracture group. Compared to the control group, the fracture group showed higher ICCs. Interobserver ICCs were especially lower in the control group. There were statistically significant correlations between CTI and DEXA (r=0.50~0.58, p<0.05). In the analysis of ROC curves, a mean threshold for CTI set a value of 0.54 (0.53~0.55), and mean sensitivity and specificity were 75.5% (69~79%) and 67.8% (65~78%), respectively. CONCLUSION: CTI showed reasonable reliability and correlation with DEXA results. CTI was a useful radiographic parameter to alert the surgeon to recommend referral for osteoporosis evaluation in elderly hip fracture patients.

Fractal analysis of mandibular trabecular bone: optimal tile sizes for the tile counting method

PURPOSE: This study was performed to determine the optimal tile size for the fractal dimension of the mandibular trabecular bone using a tile counting method. MATERIALS AND METHODS: Digital intraoral radiographic images were obtained at the mandibular angle, molar, premolar, and incisor regions of 29 human dry mandibles. After preprocessing, the parameters representing morphometric characteristics of the trabecular bone were calculated. The fractal dimensions of the processed images were analyzed in various tile sizes by the tile counting method. RESULTS: The optimal range of tile size was 0.132 mm to 0.396 mm for the fractal dimension using the tile counting method. The sizes were closely related to the morphometric parameters. CONCLUSION: The fractal dimension of mandibular trabecular bone, as calculated with the tile counting method, can be best characterized with a range of tile sizes from 0.132 to 0.396 mm.

Dentifrício de baixa concentração de fluoreto: efeito em esmalte e dentina de dentes decíduos / Low-fluoride dentifrice: deciduos enamel and dentin effect

Esta tese constituiu-se de três artigos que tiveram como objetivo: identificar a evidência científica disponível quanto à eficácia dos dentifrícios de concentração reduzida de fluoreto (500µgF/g) comparados ao dentifrício convencional (1100µgF/g) no controle de cárie dentaria na infância; avaliar a desmineralização do esmalte e da dentina decídua frente ao desafio cariogênico na presença de dentifrício 500 F comparado ao 1100; avaliar a subtração radiográfica digital, comparada a microdureza transversa, como método de detecção de perda mineral em esmalte e dentina decíduos. Após a revisão sistemática da literatura (artigo 1), 177 publicações comparando dentifrícios de diferentes concentrações de flúor (F) foram identificadas e destas, apenas 10 foram selecionadas (4 experimentos in vitro; 1 in situ; 3 ensaios populacionais e 2 ensaios clínicos randomizados). Os estudos laboratoriais indicaram a superioridade do dentifrício 1100 em relação ao 500. Os estudos clínicos apontam para a equivalência de efeito entre 500 e 1100, exceto em crianças de diferentes perfis de atividade de cárie. Concluiu-se que não há evidência de superioridade de efeito do dentifrício 1100 em relação ao 500, exceto para crianças de alto risco ou com atividade cariosa. O artigo 2 constituiu-se de um experimento in situ cruzado randomizado no qual 15 voluntários utilizaram, em 3 fases de 14 dias, dispositivos palatinos contendo blocos de esmalte e dentina coronária decíduos. O desafio cariogênico (sacarose 20% 8x/dia) foi estabelecido concomitantemente ao uso de dentifrícios 500, 1100 e sem F. Após cada fase experimental, o biofilme foi analisado e os blocos seccionados para aferir a microdureza transversa. Para a análise dos dados, ANOVA e teste de Tuckey foram utilizados. A concentração de F no biofilme do grupo sem F foi significativamente inferior aos grupos 500 e 1100, tanto em esmalte quanto em dentina. Em esmalte, a perda mineral foi...

This thesis consisted of three articles that aimed to: identify the available scientific evidence regarding the efficacy of low fluoride (F) concentration dentifrice (500µgF/g) compared to conventional F-dentifrice (1100µgF/g) in infant caries; evaluate the demineralization of deciduous enamel and dentine during a cariogenic challenge in the presence of low-F dentifrice compared to conventional dentifrice; evaluate digital subtraction radiography compared to transversal microhardness as a method of mineral loss detection in deciduous enamel and dentine. A systematic review (article 1) identified 177 publications of which only 10 (4 in vitro and 1 in situ experiments, 3 field trials and 2 randomized clinical trials) compared different F-dentifrices concentrations were then selected. Laboratory studies indicated a superiority of the 1100 compared to the 500 F-dentifrices. Clinical studies pointed out for an equivalence effect between 500 and 1100 F-dentifrices, except in children with different profiles of caries activity. It was concluded that there is no evidence of superiority of the 1100 compared to the 500 F-dentifrices except for high-risk children. Article 2 was a randomized crossover in situ experiment, including 15 volunteers that used palatal devices containing deciduous enamel and coronal slabs for periods of 14-days. A cariogenic challenge (20% sucrose 8x/day) was established concomitantly to the use of 500, 1100 and non-F dentifrices slurries. After each phase, the dental biofilm formed was analyzed and the slabs were prepared for cross-sectional microhardness measurements. Tuckey's test was used for post-ANOVA comparisons. The effect of F-dentifrices in enamel was observed only at 10µm from the surface, but no significant difference was observed between 500 and 1100 F-dentifrices. In dentin, the effect of 1100-F dentifrice was observed deeper, presenting significantly less mineral loss than 500 and non-F...

Degradação do revelador kodak por meio da análise da densidade óptica / Kodak developer degradation by optical density analysis

O propósito neste trabalho foi de analisar a degradação do revelador convencional Kodak por meio da análise da densidade óptica de radiografias digitalizadas. Foram utilizados 57 filmes periapicais Ektaspeed da marca Kodak obtendo-se radiografias da região de molares inferiores de uma mandíbula seca em um aparelho de raios X Gendex 765DC. As películas foram processadas em câmara escura portátil em um número de três ao dia perfazendo um total de 27 dias de experimento. As radiografias foram escaneadas em um escaner HPScanjet 6100C e com o auxílio do software Image Tool 1,27 foi realizada a leitura média das densidades ópticas das películas obtendo-se a curva da degradação. Observamos que o início da degradação se dá com a densidade óptica ≥ 80, após 21 dias do início do experimento.

The aim in this study was to analyse the degradation of Kodak conventional developer by analysis of optical density in digitalised radiographs. Fifty seven Kodak Estaspeed periapicals films were used achieving radiographs of molars region of a dry mandible, in a Gendex 765DC machine. The films were processed in a red box three times a day during a period of 27 days. The radiographs were digitalized in a HPSanjet 6100C scanner. Using the Image Tool 1,27 software the mean of optical densities and a degradation curve were acquired. We observed the begining of degradation after 21 days from the first radiograph, when the optical density was ≥ 80.

Clinical Application for Radiographic Body in Patients with Osteoarthritis of the Knee / 医学研究杂志

Objective To explore the clinical application for various radiographic body in patients with osteoarthritis of the knee.Methods The exact data of various image body for the joint cavity of knee and patella-femur was got by making use of radiographic body for double knee joint weight-bear AP & LAT and flexuosity weight-bear PA,flexuosity weight-bear axial position for double patella and weight-bear double total length lower extremities.Results Data of the knee joint exterior angle for 75 patients with osteoarthritis of the knee weight-bear AP and keep down AP was measure.Software of statistics for partnership t test was employed and that P

Reprodutibilidade diagnóstica das imagens radiográficas panorâmicas convencional e digitalizada invertida na detecção do teto do canal da mandíbula e do forame mentual / Diagnostic reproducibility of the conventional and negative digitized panoramic images of mandibular canal's superior wall and mentual foramen

Com o advento do implantes, a precisa localização de estruturas anatômicas, dentre elas o canal da mandíbula e o forame mentual, tornou-se uma necessidade primordial para os implantodontistas. O objetivo deste trabalho foi avaliar a reprodutibilidade diagnóstica da imagem panorâmica convencional e digitalizada invertida na detecção do teto do canal da mandíbula e do forame mentual. Foi utilizada uma amostra de setenta e sete radiografias panorâmicas de edentados totais. Estas foram digitalizadas por meio de um escaner, tendo o brilho e o contraste ajustado, bem como a transformação em negativo. A área posterior ao forame mentual foi dividida em três regiões e a presença do teto do canal foi classificada em uma escala de confiança de cinco pontos. O forame mentual foi classificado segundo os critérios propostos por Yosue et al.74 (1989). Tanto a panorâmica convencional, como a digitalizada invertida foram avaliadas por três implantodontistas, previamente calibrados, em duas ocasiões distintas com intervalo mínimo de dez dias. A reprodutibilidade intra-examinador foi avaliada empregando-se a estatística Kappa (k), segundo Light (kL). A concordância intra- examinador, segundo Landis & Kock31, variou em sofrível, regular e boa; entretanto, não houve diferença estatísticamente significante na maioria das situações. Concluímos que os valores foram de baixa concordância por ponto e por intervalo de confiança, quando os três examinadores avaliaram a presença do teto do canal da mandíbula e do forame mentual

The knowledge of precise location of mandibular canal and mentual foramen are very important in mandibular implant surgery. The aim of this study was to evaluate the diagnostic reproducibility of conventional and negative digitized conventional panoramic images of superior wall of mandibular canal and mentual foramen. A sample of 77 edentulous patient's panoramic radiographs was used. These radiographs were digitized by a scanner with adjusted bright and contrast and it showed in a negative mode. The posterior segment behind mentual foramen was divided into three parts and the presence of the superior wall of mandibular canal was classified according to five points scale. The mental foramen was classified according to criteria of Yosue et al,77 (1989). The conventional panoramic and digitized radiographies were evaluated twice by three previously calibrated implantodontits. The intra-observer reproducibility was found using Kappa's statistic, according Ligth. The intra-observer agreement varied between bearable and good according to Landis & Kock. However, there was no significant difference. We observed low agreement in the Kappa's values