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1.
J Comput Assist Tomogr ; 43(5): 718-720, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31609292

RESUMO

Recently, a novel 3-dimensional visualization methodology for volumetric computed tomography data has become available. This method, known as cinematic rendering, uses an advanced lighting model to create photorealistic images from standard computed tomography acquisition data composed of isotropic voxels. We have observed that cinematic rendering visualizations in which patients have been administered dense, positive oral contrast do not have any substantive visual artifacts and can be used to demonstrate bowel pathology to advantage (ie, "virtual fluoroscopy"). In this technical note, we describe our acquisition and visualization parameters, and we also include demonstrative examples.


Assuntos
Meios de Contraste/administração & dosagem , Enterite/diagnóstico por imagem , Imagem Tridimensional/métodos , Intussuscepção/diagnóstico por imagem , Iohexol/administração & dosagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Artefatos , Feminino , Fluoroscopia , Humanos , Interpretação de Imagem Radiográfica Assistida por Computador
2.
Am J Orthod Dentofacial Orthop ; 156(4): 493-501, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31582121

RESUMO

INTRODUCTION: The purpose of this research was to evaluate dental compensation in facial asymmetry and its correlation with skeletal variables using cone-beam computed tomography. METHODS: Sixty adult patients were retrospectively divided into asymmetry (mean age, 21.8 ± 5.4 years) and symmetry groups (mean age, 28.1 ± 4.1 years); both groups comprised 30 patients. Independent and paired t tests were used for comparisons between the asymmetry and symmetry groups and between deviated (Dv) and nondeviated (NDv) sides of the asymmetry group, respectively. Pearson correlation between dental and skeletal variables was performed. RESULTS: The mean value of menton deviation was 9.4 mm in the asymmetry group. Compared with the symmetry group, the direction and amount of dental compensation of the asymmetry group were as follows: 2.5-mm extrusion of the maxillary first molar (UM6) at NDv (P <0.05); 1.8-mm higher position of the mandibular canine (LC) from the mandibular horizontal plane using mental foramen (MHP_mf) at NDv (P <0.05); 6°-more buccoversion of UM6 at Dv; 3.7°-more linguoversion of UM6 at NDv; 4.8°-more buccoversion of the maxillary canine (UC) at Dv; 4.9°-more buccoversion of the mandibular molar (LM6) at NDv; and 2.6°-more linguoversion of LC at Dv. Dental compensation correlated or marginally correlated with skeletal variables of the deviated mandible. CONCLUSIONS: Dental compensations, extrusion of the maxillary molars on the NDv, and buccal tipping of the maxillary teeth and lingual tipping of the mandibular teeth on the Dv, were observed. The mandibular body length was associated with linguoversion of the mandibular molars on the Dv. The ramal inclination was related to the extrusion of the maxillary molars on the NDv.


Assuntos
Cefalometria/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Assimetria Facial/diagnóstico por imagem , Má Oclusão/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Adolescente , Adulto , Estética Dentária , Assimetria Facial/fisiopatologia , Feminino , Humanos , Imagem Tridimensional/métodos , Masculino , Má Oclusão/fisiopatologia , Pessoa de Meia-Idade , Dente Molar/fisiopatologia , Estudos Retrospectivos
3.
Am J Orthod Dentofacial Orthop ; 156(4): 566-573, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31582128

RESUMO

INTRODUCTION: Accurate root position is imperative for successful orthodontic treatment that is stable and functional. Current methods to monitor root position are either inaccurate or use relatively high levels of radiation. A method to generate an expected root position (ERP) setup has been reported to have the potential to accurately evaluate root position with minimal radiation. The purpose of this study was to determine the accuracy and reliability of the clinical decisions made on root position using the ERP setup. METHODS: This retrospective study included 10 subjects who had pretreatment and midtreatment cone-beam computed tomography (CBCT) scans and study models. An ERP setup was generated for all patients at midtreatment. Four examiners assessed both the CBCT scan and ERP setup and made clinical decisions regarding the root position with each method. Cohen's kappa was determined to assess intraoperator and intermethod reliability. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated to determine the accuracy of the ERP setup. RESULTS: The kappa values for intraoperator reliability for both the CBCT scan and ERP setup fell within the 0.61-0.80 range. The kappa values for intermethod reliability between the CBCT scan and ERP setup fell within the 0.61-0.80 range for all tooth groups. The sensitivity of the ERP setup ranged from 0.72 to 0.90, specificity ranged from 0.89 to 0.97, positive predictive value ranged from 0.57 to 0.85, and negative predictive value ranged from 0.93 to 0.99. CONCLUSIONS: This study demonstrated that the ERP setup, when compared with the gold standard CBCT scan, was accurate and reliable in making clinical decisions regarding root position at midtreatment.


Assuntos
Tomada de Decisão Clínica , Tomografia Computadorizada de Feixe Cônico/métodos , Imagem Tridimensional/métodos , Técnicas de Movimentação Dentária , Raiz Dentária/anatomia & histologia , Raiz Dentária/diagnóstico por imagem , Modelos Dentários , Humanos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
4.
Am J Orthod Dentofacial Orthop ; 156(3): 326-336, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31474262

RESUMO

INTRODUCTION: Orthodontic mini-implants aid in the correction of distocclusions via direct anchorage (pull from mini-implant to teeth) and indirect anchorage (teeth pulled against other teeth anchored by the mini-implant). The aim of this study was to compare stress levels on the periodontal ligament (PDL) of maxillary buccal teeth in direct and indirect distalization against orthodontic mini-implants and accounting for individual variation in maxillary anatomy and biomechanical characteristics of the compact bone. METHODS: A 3D model of the maxilla containing the different components (teeth, PDL, trabecular and cortical bones) was generated from a computed tomographic scan. Cortical bone was divided into several areas according to previously defined zones. Bone stiffness and thickness data, obtained from 11 and 12 cadavers, respectively, were incorporated into the initial model to simulate the individual cortical bone variation at the different locations. Subsequently, a finite element analysis was used to simulate the distalization modalities. RESULTS: Stresses at the buccal, palatal, mesial, and distal surfaces were significantly different between adjacent teeth under stiffness but not thickness variation. In both distalization modalities, low or no significant correlations were found between stress values and corresponding cortical bone thicknesses. High significant and inverted correlations were observed at the first molar between stress amounts and cortical bone stiffness (direct modality: -0.68 < r < -0.72; indirect modality: -0.80 < r < -0.82; P <0.05). CONCLUSIONS: With the use of a novel finite element approach that integrated human data on variations in bone properties, findings suggested that cortical bone stiffness may influence tooth movement more than bone thickness. Significant clinical implications could be related to these findings.


Assuntos
Análise do Estresse Dentário/métodos , Análise de Elementos Finitos , Técnicas de Movimentação Dentária/métodos , Fenômenos Biomecânicos , Parafusos Ósseos , Simulação por Computador , Implantes Dentários , Humanos , Imagem Tridimensional/métodos , Maxila/anatomia & histologia , Maxila/diagnóstico por imagem , Modelos Anatômicos , Dente Molar , Procedimentos de Ancoragem Ortodôntica/instrumentação , Procedimentos de Ancoragem Ortodôntica/métodos , Desenho de Aparelho Ortodôntico , Ligamento Periodontal , Estresse Mecânico , Técnicas de Movimentação Dentária/instrumentação , Torção Mecânica
5.
Am J Orthod Dentofacial Orthop ; 156(3): 337-344, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31474263

RESUMO

INTRODUCTION: Clinical evaluation of the midface including the paranasal and upper lip regions is highly subjective and complex. Traditional and 3-dimensional cephalometrics were not developed with the clinical appearance of these midfacial areas in mind and are therefore inappropriate surrogates for the clinical appearance of the midface, making them unsuitable as aids in diagnosing dentofacial deformities. The aim of this study was to evaluate traditional as well as newly defined landmarks and measurements and their correlation with clinical appearance of the midface. METHODS: Fifty-two subjects who underwent full-field cone-beam computed tomography were recruited for this study. A single examiner assessed each subject's midfacial region (paranasal and upper lip), and a second examiner obtained traditional and newly defined cephalometric measurements for each subject. Both examiners were blinded to each other's data throughout the study. Statistical analysis was performed to assess the correlations of the traditional and novel cephalometric measurements with clinical midfacial findings. The impact of the soft tissue thickness in the paranasal region was also analyzed. The performance of any classification derived from statistically significant variables was analyzed with the use of micro-F scores and area under the receiver operating characteristic curve (AUC). RESULTS: Both traditional (SNA) and newly defined measurements (SNANS, SNPR, SNNP, SNh) had no statistically significant correlation with clinical paranasal diagnosis. However, in the absence of upper lip procumbency or protrusion, SNNP and SNh had statistically significant correlations with clinical paranasal diagnosis (P = 0.047 and P = 0.003, respectively). For upper lip analysis, both traditional (SNA) and newly defined measurements (SNCEJ) had strong correlations with clinical upper lip diagnosis (P < 0.001). All statistically significant cephalometric variables had good intra- and interobserver reliability (correlation coefficients ≥0.972 and ≥ 0.968, respectively) except SNA, which had a low interobserver reliability (correlation coefficient 0.739). Fitted models for paranasal and upper lip analyses showed low micro-F scores, indicating low precision and recall. However, AUC values of 0.7019 and 0.6362 for the paranasal and upper lip analysis, respectively, suggest improved performance of the model when properly trained with a larger sample size. CONCLUSIONS: Newly defined measurements SNh and SNNP correlated with clinical paranasal diagnosis only in the absence of upper lip procumbency and protrusion. SNA and SNCEJ were strongly correlated with clinical upper lip diagnosis. However, fitted models based on this study sample yielded low micro-F scores, making the fitted models currently unsuitable for anything besides correlation with clinical findings. A larger sample size will be necessary to further clarify the potential roles of these measurements, especially given the reasonable AUC values. The findings of this study demonstrate the highly subjective and relative nature of midfacial diagnosis and the importance of clinical judgment despite the potential utility of some traditional and new measurements.


Assuntos
Pontos de Referência Anatômicos/anatomia & histologia , Pontos de Referência Anatômicos/diagnóstico por imagem , Cefalometria/métodos , Imagem Tridimensional/métodos , Maxila/anatomia & histologia , Maxila/diagnóstico por imagem , Adolescente , Adulto , Criança , Tomografia Computadorizada de Feixe Cônico/métodos , Face/anatomia & histologia , Face/diagnóstico por imagem , Feminino , Humanos , Imagem Tridimensional/estatística & dados numéricos , Lábio/anatomia & histologia , Lábio/diagnóstico por imagem , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
6.
Am J Orthod Dentofacial Orthop ; 156(3): 365-374, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31474266

RESUMO

INTRODUCTION: We sought the 3-dimensional (3D) zone of the center of resistance (ZCR) of mandibular posterior teeth groups (group 1: first molar; group 2: both molars; group 3: both molars and second premolar; group 4: both molars and both premolars) with the use of 3D finite element analysis. METHODS: 3D finite element models comprised the mandibular posterior teeth, periodontal ligament, and alveolar bone. In the symmetric bilateral model, a 100-g midline force was applied on a median sagittal plane at 0.1-mm intervals to determine the anteroposterior and vertical positions of the ZCR (where the applied force induced translation). The most reliable buccolingual position of the ZCR was then determined in the unilateral model. The combination of the anteroposterior, vertical, and buccolingual positions was defined as the ZCR. RESULTS: The ZCRs of groups 1-4 were, respectively, 0.48, 0.46, 0.50, and 0.53 of the mandibular first molar root length from the alveolar crest level and located slightly distobuccally at anteroposterior ratios of 2:3.0, 2:2.3, 2:2.4, and 2:2.5 to each sectional arch length and at buccolingual ratios of 2:1.5, 2:1.1, 2:1.6, and 2:2.4 to the first molar's buccolingual width. CONCLUSIONS: The ZCR can be a useful reference for 3D movement planning of mandibular posterior teeth or segments.


Assuntos
Imagem Tridimensional/métodos , Mandíbula/anatomia & histologia , Mandíbula/diagnóstico por imagem , Dente/anatomia & histologia , Dente/diagnóstico por imagem , Processo Alveolar/anatomia & histologia , Processo Alveolar/diagnóstico por imagem , Dente Pré-Molar/anatomia & histologia , Dente Pré-Molar/diagnóstico por imagem , Arco Dental , Modelos Dentários , Análise de Elementos Finitos , Humanos , Dente Molar/anatomia & histologia , Dente Molar/diagnóstico por imagem , Ortodontia Corretiva , Ligamento Periodontal/anatomia & histologia , Ligamento Periodontal/diagnóstico por imagem , Técnicas de Movimentação Dentária
7.
Am J Orthod Dentofacial Orthop ; 156(3): 420-428, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31474272

RESUMO

INTRODUCTION: This study aimed to test the accuracy of the 3-dimensional (3D) digital dental models generated by the Dental Monitoring (DM) smartphone application in both photograph and video modes over successive DM examinations in comparison with 3D digital dental models generated by the iTero Element intraoral scanner. METHODS: Ten typodonts with setups of class I malocclusion and comparable severity of anterior crowding were used in the study. iTero Element scans along with DM examination in photograph and video modes were performed before tooth movement and after each set of 10 Invisalign aligners for each typodont. Stereolithography (STL) files generated from the DM examinations in photograph and video modes were superimposed with the STL files from the iTero scans using GOM Inspect software to determine the accuracy of both photograph and video modes of DM technology. RESULTS: No clinically significant differences, according to the American Board of Orthodontics-determined standards, were found. Mean global deviations for the maxillary arch ranged from 0.00149 to 0.02756 mm in photograph mode and from 0.0148 to 0.0256 mm in video mode. Mean global deviations for the mandibular arch ranged from 0.0164 to 0.0275 mm in photograph mode and from 0.0150 to 0.0264 mm in video mode. Statistically significant differences were found between the 3D models generated by the iTero and the DM application in photograph and video modes over successive DM examinations. CONCLUSIONS: 3D digital dental models generated by the DM smartphone application in photograph and video modes are accurate enough to be used for clinical applications.


Assuntos
Confiabilidade dos Dados , Técnica de Moldagem Odontológica , Modelos Dentários , Processamento de Imagem Assistida por Computador/métodos , Imagem Tridimensional/métodos , Projeto Auxiliado por Computador , Arco Dental , Humanos , Má Oclusão/diagnóstico por imagem , Aparelhos Ortodônticos/normas , Aparelhos Ortodônticos Removíveis , Ortodontia/normas , Fotografia Dentária , Smartphone , Software , Estereolitografia , Tecnologia Odontológica/métodos , Técnicas de Movimentação Dentária , Gravação em Vídeo
8.
Medicine (Baltimore) ; 98(37): e17142, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31517856

RESUMO

Morphological data of talus are important for the design of talar prostheses. The talar morphology of Chinese population has been rarely reported. This study adopted a three-dimensional (3D) measurement approach to provide accurate data for the anatomical morphology of talus in Northeast Chinese population and compared it with that of foreigners.One hundred forty-six healthy subjects form Northeast China underwent computed tomography (CT) arthrography. 3D digital talar model was reconstructed and thirteen morphological parameters were measured through Mimics and Magics software. Length and breadth indexes of total talus, trochlea, medial and lateral malleolus articular surface were mainly selected. Statistical analysis was conducted by independent-samples and paired-samples t test through SPSS software.All the indexes were normally distributed. No significant difference between left and right talus was identified in either males or females (P > .05). Most of the indexes showed significant sexual differences except the radian of lateral malleolus articular surface and the posterior breadth of trochlea (P < .05). The talar anatomy of Chinese subjects is different from the published data in other populations.The promising approach adopted in this study addresses some inconvenience with previous conventional methods on cadaver specimens. The geometric parameters of talus in Chinese population differ from those in other populations. The talar measurements and morphology analysis in this study suggest that population characteristics should be taken into account. This study will provide references for the design of talar prostheses in Chinese population.


Assuntos
Imagem Tridimensional , Ossos do Tarso/anatomia & histologia , Ossos do Tarso/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , China , Feminino , Humanos , Imagem Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Tamanho do Órgão , Reprodutibilidade dos Testes , Caracteres Sexuais , Software , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
9.
Am J Orthod Dentofacial Orthop ; 156(2): 210-219, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31375231

RESUMO

INTRODUCTION: More patients are choosing customized orthodontic appliances because of their excellent esthetics. It is essential that clinicians understand the biomechanics of the tooth movement tendency in customized lingual orthodontics. This study aimed to evaluate the tooth movement tendency during space closure in maxillary anterior teeth with the use of miniscrew anchorage in customized lingual orthodontics with various power arm locations. METHODS: Three-dimensional finite element models of the maxilla were created with miniscrews and power arms; the positions were varied to change the force directions. A retraction force (1.5 N) was applied from the top of the miniscrews to the selected points on the power arm, and the initial displacements of the reference nodes of the maxillary teeth were analyzed. RESULTS: After applying force in different directions, power arms located at the distal side of the canines led to larger initial lingual crown tipping and occlusal crown extrusion of the maxillary incisors compared with power arms located at the midpoint between the lateral incisors and canines, and caused a decreasing trend of the intercanine width. CONCLUSIONS: In customized lingual orthodontic treatment, power arms located at the distal side of the canines are unfavorable for anterior teeth torque control and intercanine width control. Power arms located at the midpoint between the lateral incisors and canines can get better torque control, but still cannot achieve excepted torque without extra torque control methods, no matter whether its force application point is higher than, lower than, or equal to the level of the top of the miniscrews.


Assuntos
Parafusos Ósseos , Análise de Elementos Finitos , Procedimentos de Ancoragem Ortodôntica/instrumentação , Procedimentos de Ancoragem Ortodôntica/métodos , Fechamento de Espaço Ortodôntico , Técnicas de Movimentação Dentária/instrumentação , Técnicas de Movimentação Dentária/métodos , Adulto , Fenômenos Biomecânicos , Simulação por Computador , Dente Canino/patologia , Humanos , Imagem Tridimensional/métodos , Incisivo/patologia , Maxila , Modelos Biológicos , Desenho de Aparelho Ortodôntico , Aparelhos Ortodônticos , Braquetes Ortodônticos , Fechamento de Espaço Ortodôntico/instrumentação , Fechamento de Espaço Ortodôntico/métodos , Fios Ortodônticos , Planejamento de Assistência ao Paciente , Estresse Mecânico , Coroa do Dente , Torque , Resultado do Tratamento
10.
Am J Orthod Dentofacial Orthop ; 156(2): 257-265, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31375236

RESUMO

INTRODUCTION: Children with unilateral cleft lip and palate (UCLP) exhibit snoring and mouth breathing. They are also reported to show obstructive sleep apnea syndrome. However, their upper airway ventilation condition is not clearly understood. Therefore, this study was performed to evaluate upper airway ventilation condition in children with UCLP with the use of computational fluid dynamics. METHODS: Twenty-one children (12 boys, 9 girls; mean age 9.1 years) with UCLP and 25 children (13 boys, 12 girls; mean age 9.2 years) without UCLP who required orthodontic treatment underwent cone-beam computed tomography (CBCT). Nasal resistance and upper airway ventilation condition were evaluated with the use of computational fluid dynamics from CBCT data. The groups were compared with the use of Mann-Whitney U tests and Student t tests. RESULTS: Nasal resistance of the UCLP group (0.97 Pa/cm3/s) was significantly higher than that of the control group (0.26 Pa/cm3/s; P < 0.001). Maximal pressure of the upper airway (335.02 Pa) was significantly higher in the UCLP group than in the control group (67.57 Pa; P < 0.001). Pharyngeal airway (from choanae to base of epiglottis) pressure in the UCLP group (140.46 Pa) was significantly higher than in the control group (15.92 Pa; P < 0.02). CONCLUSIONS: Upper airway obstruction in children with UCLP resulted from both nasal and pharyngeal airway effects.


Assuntos
Fenda Labial/patologia , Fissura Palatina/patologia , Tomografia Computadorizada de Feixe Cônico/métodos , Hidrodinâmica , Laringe/anatomia & histologia , Nariz/anatomia & histologia , Tonsila Faríngea/anatomia & histologia , Pontos de Referência Anatômicos , Criança , Fenda Labial/diagnóstico por imagem , Fissura Palatina/diagnóstico por imagem , Epiglote/anatomia & histologia , Epiglote/diagnóstico por imagem , Feminino , Humanos , Osso Hioide/anatomia & histologia , Imagem Tridimensional/métodos , Laringe/diagnóstico por imagem , Má Oclusão de Angle Classe I , Nasofaringe/anatomia & histologia , Nasofaringe/diagnóstico por imagem , Nariz/diagnóstico por imagem , Respiração , Apneia Obstrutiva do Sono
11.
J Craniofac Surg ; 30(5): 1435-1440, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31299738

RESUMO

PURPOSE: The aim of this study was to establish a new method of facial soft tissue analysis based on 3dMDface system and to find the different esthetic preferences of Chinese beauties from the Chinese and Indian evaluators perspective. METHODS: Three-dimensional facial images of 242 females and 168 males were evaluated and ranked by 8 Chinese and nine Indians using a 10-point visual analog scale (VAS). Total 120 subjects in 2 panels (from Chinese perspective and Indian perspective) including 30 male and 30 female faces with top 30 scores were analyzed with the "average face" method respectively. Then 17 linear measurements, 13 curve measurements and 14 ratios of 4 average faces were calculated and compared with the divine proportion. RESULTS: Distinct differences were founded based on the average face analysis. Similar total facial types were preferred by both Chinese and Indian evaluators, while Indian evaluators preferred a wider male face with a protrusive lower lip. Delicate noses with lower nose ridge but protrusive lower lips in females were more acceptable by Indian evaluators. The differences of linear measurements were limited in 2.0 mm except the facial width, lower facial width, upper facial height and forehead height while curve measurements differ distinctly as the table shows. No ratios equal to the divine proportion were founded. CONCLUSION: The 3D Average face based on stereophotogrammetry is a feasible method to analyze the facial characters and discrepancy of esthetic preferences. Chinese and Indian evaluators have some certain differences when judging beauties. Attractive faces have some certain ratios but not the divine proportion.


Assuntos
Face/anatomia & histologia , Adolescente , Adulto , Grupo com Ancestrais do Continente Asiático , Beleza , Feminino , Humanos , Imagem Tridimensional/métodos , Masculino , Fotogrametria/métodos , Escala Visual Analógica , Adulto Jovem
12.
Nat Commun ; 10(1): 2781, 2019 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-31273194

RESUMO

Recent advances in optical clearing and light-sheet microscopy have provided unprecedented access to structural and molecular information from intact tissues. However, current light-sheet microscopes have imposed constraints on the size, shape, number of specimens, and compatibility with various clearing protocols. Here we present a multi-immersion open-top light-sheet microscope that enables simple mounting of multiple specimens processed with a variety of clearing protocols, which will facilitate wide adoption by preclinical researchers and clinical laboratories. In particular, the open-top geometry provides unsurpassed versatility to interface with a wide range of accessory technologies in the future.


Assuntos
Microscopia de Fluorescência/métodos , Animais , Encéfalo/diagnóstico por imagem , Desenho de Equipamento , Humanos , Imagem Tridimensional/instrumentação , Imagem Tridimensional/métodos , Pulmão/diagnóstico por imagem , Linfonodos/diagnóstico por imagem , Masculino , Camundongos , Microscopia de Fluorescência/instrumentação , Próstata/diagnóstico por imagem
13.
J Comput Assist Tomogr ; 43(5): 708-712, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31356523

RESUMO

OBJECTIVE: Meningioma-related skull magnetic resonance imaging findings other than hyperostosis are not widely recognized. We evaluated the novel findings of the skull adjacent to meningiomas. METHODS: Records from patients with meningiomas located adjacent to the skull on magnetic resonance imaging (n = 32) were included. Three skull findings (intramedullary prominent vessel, intramedullary enhancement, intramedullary T2-hyperintensity) and the widely known hyperostosis were retrospectively visually assessed. The frequency of these 3 findings and the relevance to each other, and their relationships with hyperostosis, size, length adjacent to the skull, and relative signal intensity of the meningioma were examined. RESULTS: The incidence of the three findings was 46.88%, 53.13%, and 62.5%, respectively, and that of hyperostosis was 46.88%. Each association involving the findings was strong, and they were significantly related to the size and length. CONCLUSIONS: Intramedullary prominent vessel, intramedullary enhancement, and intramedullary T2-hyperintensity may be novel characteristic skull findings associated with meningioma.


Assuntos
Imagem Tridimensional/métodos , Imagem por Ressonância Magnética/métodos , Neoplasias Meníngeas/diagnóstico por imagem , Meningioma/diagnóstico por imagem , Crânio/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Hiperostose/diagnóstico por imagem , Hiperostose/cirurgia , Interpretação de Imagem Assistida por Computador , Masculino , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Pessoa de Meia-Idade , Estudos Retrospectivos , Crânio/cirurgia
14.
Br J Radiol ; 92(1101): 20190155, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31276426

RESUMO

OBJECTIVE: To develop and validate clinical-radiomics nomograms based on three-dimensional CT and multiparametric MRI (mpMRI) for pre-operative differentiation of sacral chordoma (SC) and sacral giant cell tumor (SGCT). METHODS: A total of 83 SC and 54 SGCT patients diagnosed through surgical pathology were retrospectively analyzed. We built six models based on CT, CT enhancement (CTE), T1 weighted, T2 weighted, diffusion-weighted imaging (DWI), and contrast-enhanced T1 weighted features, two radiomics nomograms and two clinical-radiomics nomograms combined radiomics mixed features with clinical data. The area under the receiver operating characteristic curve (AUC) and accuracy (ACC) analysis were used to assess the performance of the models. RESULTS: SC and SGCT presented significant differences in terms of age, sex, and tumor location (tage = 9.00, χ2sex = 10.86, χ2location = 26.20; p < 0.01). For individual scan, the radiomics model based on diffusion-weighted imaging features yielded the highest AUC of 0.889 and ACC of 0.885, followed by CT (AUC = 0.857; ACC = 0.846) and CT enhancement (AUC = 0.833; ACC = 0.769). For the combined features, the radiomics model based on mixed CT features exhibited a better AUC of 0.942 and ACC of 0.880, whereas mixed MRI features achieved a lower performance than the individual scan. The clinical-radiomics nomogram based on combined CT features achieved the highest AUC of 0.948 and ACC of 0.920. CONCLUSIONS: The radiomics model based on CT and multiparametricMRI present a certain predictive value in distinguishing SC and SGCT, which can be used for auxiliary diagnosis before operation. The clinical-radiomics nomograms performed better than radiomics nomograms. ADVANCES IN KNOWLEDGE: Clinical-radiomics nomograms based on CT and mpMRI features can be used for preoperative differentiation of SC and SGCT.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Cordoma/diagnóstico por imagem , Tumor de Células Gigantes do Osso/diagnóstico por imagem , Imagem Tridimensional/métodos , Cuidados Pré-Operatórios/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nomogramas , Estudos Retrospectivos , Sacro/diagnóstico por imagem
15.
Rev. Ciênc. Plur ; 5(1): 113-123, jun. 2019. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-1007364

RESUMO

Introdução:lentes de contato dentais podem ser uma excelente opção para correção de cor, forma, tamanho e posicionamento dental. Entretanto é umtratamentoque requer várias etapas laboratoriais com riscos de distorções nas etapas de moldagem e vazamento do modelo. Desta forma, desadaptações dos laminados em boca podem ser frequentes.Objetivo:relatar um caso clínico de nove laminados cerâmicos em que foi empregado o escaneamento digital, troquelização virtual e prototipagem do modelo em 3D.Método:paciente do gênero feminino, 59 anos, buscou atendimento odontológico queixando-se de desproporcionalidade dentária ao sorrir. Ao exame clínico foi observada uma inclinação maxilar que causava aquela desarmonia. Foi proposta a confecção de laminados cerâmicos para compensar a discrepância óssea bem como melhorar forma, contorno e cromia dentária. Após planejamento digital, confecção do enceramento diagnóstico, mock up, e aceita do planejamento por parte da paciente, iniciaram-se os preparos dentários. Finalizada esta etapa, os dentes foram escaneados (Trios 3Shape), troquelizados e prototipados em impressora 3D. O modelo foi encaminhado ao laboratório que confeccionou as peças protéticas em dissilicato de lítio de forma injetada e maquiada. Por fim, foram realizadas as provas secas, úmidas, ajustes necessários e cimentação dos laminados com cimento resinoso fotopolimerizável.Conclusão:a tecnologia empregada se mostrou eficiente na resolução do caso, sendo uma técnica rápida, que causou pouco desconforto à paciente e oportunizou uma boa adaptação dos laminados cerâmicos (AU).


Introduction:laminates veneers can be an excellent choice for color correction, shape, size and dental positioning. However, it is a technique that requires several laboratory steps with risks of distortion in the molding and casting steps of the model. Thus, maladjustments of laminatesin the mouth may be frequent.Objective:to report a clinical case of nine ceramic laminates through the digital scanning, virtual punching and 3D prototyping of the model.Methods:A 59 years old woman showed up to dental clinic searched dental care complaining of dental disproportionality when smiling. At the clinical examination, a maxillary inclination was observed that caused disharmony. It was proposed the making of ceramic laminates to compensate the bone discrepancy as well as improve shape, contour and dental color. After the digital planning, preparation diagnostic wax-up, mock up, and acceptance of patient planning, the dental preparations were started. After this step, the teeth were scanned (Trios 3Shape), punched and prototyped in a 3D printer. The model was sent to the laboratory to do the prosthetic parts in lithium disilicate in an injected and makeup manner. At last, it were made the tests dry, wet, required adjustments finally cementation of the ceramic laminates with photopolymerizable resin cement. Conclusions:the technology employed was efficient in solving this case, being a fast technique, which caused little discomfort to the patient and provided a good adaptation of the ceramic laminates (AU).


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Tecnologia Odontológica/métodos , Imagem Tridimensional/métodos , Porcelana Dentária , Facetas Dentárias , Estética Dentária , Brasil
16.
Am J Orthod Dentofacial Orthop ; 156(1): 53-60, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31256838

RESUMO

INTRODUCTION: Pharyngeal airway space (PAS) assessment has been used in the past for a better understanding of orthodontic and surgical outcomes; however, this analysis could be unreliable. Our objective was to evaluate possible changes in the PAS reading in the same patient from their consecutive cone-beam computed tomography (CBCT) scans. METHODS: We evaluated a total of 27 patients' CBCT scans obtained at 2 time points with the use of a standardized acquisition protocol. The mean age at T0 was 31 years (range 17-62 years) and the follow-up records (T1) were taken after 4-6 months. Dolphin Imaging software was used to measure the volumes of the nasopharynx, oropharynx, and hypopharynx. We also evaluated the craniocervical position with the use of a lateral cephalogram. RESULTS: The variables exhibited high intraclass correlation coefficients (ICCs) when measuring the same CBCT scan twice (T0 and T0). However, The ICC between the measurements performed on the first and second CBCT scans (T0 and T1) showed that the only variable with high reproducibility between the 2 scans was cranial base, with an ICC >0.97. Average differences of 682.1 mm3, 2255.3 mm3, and 517.4 mm3 were found for the nasopharynx, oropharynx, and hypopharynx, respectively. Regarding the cephalometric angles, average differences between T0 and T1 scans were 0.6°, 2.7°, and 0.4° for OPT.CVT, OPT.SN, and cranial base, respectively. CONCLUSIONS: Different CBCT exams with equal scanning and patient positioning protocols can result in different 3D PAS readings. A more careful interpretation of CBCT volumetric data to achieve adequate conclusions of the clinical outcomes is necessary.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Tomografia Computadorizada de Feixe Cônico/normas , Posicionamento do Paciente/métodos , Posicionamento do Paciente/normas , Faringe/anatomia & histologia , Faringe/diagnóstico por imagem , Adolescente , Adulto , Cefalometria/métodos , Feminino , Seguimentos , Humanos , Hipofaringe/anatomia & histologia , Hipofaringe/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imagem Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Nasofaringe/anatomia & histologia , Nasofaringe/diagnóstico por imagem , Variações Dependentes do Observador , Orofaringe/anatomia & histologia , Orofaringe/diagnóstico por imagem , Procedimentos Cirúrgicos Ortognáticos , Valores de Referência , Reprodutibilidade dos Testes , Software , Adulto Jovem
17.
Am J Orthod Dentofacial Orthop ; 156(1): 94-103, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31256848

RESUMO

INTRODUCTION: Self-ligating appliances are purposed to expand the arches, but evidence on stability of the result is lacking. We measured the width of maxillary and mandibular arches and torque changes after treatment with the use of passive self-ligating appliances and assessed stability at the 2-year follow-up. METHODS: Maxillary and mandibular 3-dimensional (3D) models from 32 subjects (mean initial age 14.9 ± 0.9 years), consecutively treated with the use of self-ligating appliances, were obtained before, immediately after, and 2 years after treatment. Dental arches were examined with the use of 3D software to evaluate differences in transverse arch dimensions and torque values. RESULTS: An incremental increase of arch widths was recorded, especially regarding maxillary and mandibular premolars. The increase in the transverse diameters was associated with a significant positive torque gain. No significant changes in arch perimeter and depth were recorded. In the retention period, slight significant changes in transverse diameters were recorded, and a transverse diameter constriction detected. Torque values remained almost unchanged in the follow-up period. CONCLUSIONS: Transverse arch dimensions, along with torque values, increased significantly after treatment with the use of a passive self-ligating appliance. In the 2 years following treatment, a tendency to transverse diameter restriction, especially for the maxillary and mandibular premolars, was observed.


Assuntos
Arco Dental/anatomia & histologia , Má Oclusão/terapia , Aparelhos Ortodônticos , Técnica de Expansão Palatina , Técnicas de Movimentação Dentária/métodos , Torque , Adolescente , Adulto , Análise de Variância , Dente Pré-Molar , Projeto Auxiliado por Computador , Técnica de Fundição Odontológica , Modelos Dentários , Feminino , Seguimentos , Humanos , Imagem Tridimensional/métodos , Masculino , Má Oclusão/patologia , Mandíbula , Maxila , Níquel , Desenho de Aparelho Ortodôntico , Técnica de Expansão Palatina/instrumentação , Software , Titânio , Coroa do Dente/anatomia & histologia , Técnicas de Movimentação Dentária/instrumentação , Resultado do Tratamento , Adulto Jovem
18.
Ceska Gynekol ; 84(3): 222-228, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31324114

RESUMO

OBJECTIVE: An overview of current knowledge about the use of 3D ultrasound examinations for the examination of fetal CNS. DESIGN: A review article. SETTING: Department of Gynecology and Obstetrics, Faculty of Medicine and Dentistry, Palacký University and Faculty Hospital Olomouc. METHODS: Literary sources related to the subject were used, especially articles indexed by Pubmed-Medline. CONCLUSION: 3D ultrasound is currently used for examination of fetal CNS structures that can be only very difficult displayed by conventional 2D ultrasound. The best for technique for visualisation of midline fetal CNS structures, respectively corpus callosum cerebellar vermis, appears to be 3D volume acquisition in a sagittal plane through the sagittal suture or large fontanel with further post-processing in multiplanar mode, OVIX (Samsung), TUI (GE Healthcare) etc.


Assuntos
Sistema Nervoso Central/diagnóstico por imagem , Feto/diagnóstico por imagem , Imagem Tridimensional/métodos , Ultrassonografia Pré-Natal/métodos , Feminino , Humanos , Gravidez , Segundo Trimestre da Gravidez
19.
Adv Exp Med Biol ; 1156: 49-65, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31338777

RESUMO

Technology for developing three-dimensional (3D) virtual models in anatomical sciences education has seen a great improvement in recent years. Various data used for creating stereoscopic virtual models have also been constantly improving. This paper focuses specifically on the methodologies of creating stereoscopic virtual models and the techniques and materials used in developing stereoscopic virtual models from both our previous studies and other published literature. The presentation and visualization of stereoscopic models are highlighted, and the benefits and limitations of stereoscopic models are discussed. The practice of making 3D measurements on the lengths, angles, and volumes of models can potentially be used to help predict typical measurement parameters of anatomical structures and for the placement of surgical instruments. Once stereoscopic virtual models have been constructed, their visualization and presentation can be implemented in anatomy education and clinical surgical trainings.


Assuntos
Anatomia , Percepção de Profundidade , Cirurgia Geral , Imagem Tridimensional , Modelos Anatômicos , Anatomia/educação , Anatomia/métodos , Cirurgia Geral/educação , Humanos , Imagem Tridimensional/métodos
20.
BMC Ophthalmol ; 19(1): 155, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31324172

RESUMO

BACKGROUND: The object of this study is to investigate the effect of early bleb parameters measured by three-dimensional anterior-segment optical coherence tomography on the surgical success of trabeculectomy. METHODS: This retrospective study included 45 patients with 19 of exfoliation glaucoma, 17 of primary open angle glaucoma, 4 of neovascular glaucoma, 4 of uveitic glaucoma and 1 of glaucoma caused from familial amyloid polyneuropathy who underwent trabeculectomy. Bleb parameters, such as total bleb height, the position and the width of filtration openings on the scleral flap, bleb wall thickness, fluid-filled cavity height, and bleb wall intensity were assessed by three-dimensional anterior-segment optical coherence tomography 0.5 months after trabeculectomy, and were subjected to a Cox proportional hazard model as potential prognostic factors. Surgical success was defined as: IOP < 21 mmHg (A), < 18 mmHg (B), < 15 mmHg (C) with (qualified success) or without medication (complete success). Complete failure was defined as hypotony and additional glaucoma surgeries required. RESULTS: The width of filtration openings was identified as a prognostic factor for all criteria. By multivariable analysis, the width of the filtration openings was a prognostic factor in all criteria tested, and the preoperative IOP were significant prognostic factors for surgical success in qualified success in criteria B and C. Separate from the median widths of filtration openings, wide filtration opening showed significant survival ratio for qualified success in criteria A and B and for complete success in all criteria, respectively. CONCLUSIONS: The width of filtration opening at an early stage is a prognostic factor for surgical success of trabeculectomy.


Assuntos
Segmento Anterior do Olho/diagnóstico por imagem , Cirurgia Filtrante/métodos , Glaucoma/cirurgia , Imagem Tridimensional/métodos , Tomografia de Coerência Óptica/métodos , Trabeculectomia/métodos , Adulto , Idoso , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Estudos Retrospectivos
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