Navegando por Palavras-chave "Radiografia dentária digital"

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    Estudo comparativo in vitro dos níveis radiográficos de cinza de biomateriais utilizando duas modalidades de imagem digital
    (Universidade Federal de São Paulo (UNIFESP), 2009-06-24) Nobrega, Newton Fernando Sobreira [UNIFESP]; Ajzen, Sergio Aron [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Purpose: To compare direct and indirect methods using the Digora for Windows System and the Adobe Photoshop CS2 System. Methods: Samples were made of dental materials, using a matrix of metallic aluminum structure composed of two blocks coupled by a precision connection. The samples were disposed on a radiographic film and on a protected phosphor plate to be radiographed using the indirect and direct methods. The radiographic images were analyzed by the Digora for Windows system and the Adobe Photoshop system which have 256 shades of gray, followed by the delimitation of the standard area for measuring of the shades of gray. Results: The distribution of the shades of gray, analyzed by the direct and indirect methods, suggested that the greater the distance, the longer the time of exposure. Conclusion: The indirect method was a feasible alternative in the evaluation of radiographical shades of gray in dental materials since it presents significant reproductiveness in 0,2s to 0,5s exposure.
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    Acesso aberto (Open Access)
    In vitro study on radiographic gray levels of biomaterials using two digital image methods
    (Pontifícia Universidade Católica do Rio Grande do Sul, 2012-01-01) Nobrega, Newton Fernando Sobreira [UNIFESP]; Puchnick, Andrea [UNIFESP]; Cerqueira, Leandro Kfouri Martins [UNIFESP]; Costa, Claudio; Ajzen, Sergio Aron [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)
    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.