Abstract

FERREIRA COSTA, André Luis; MONTEBELLO-FILHO, Agenor; AMBROSANO BOVI, Glaucia  and  ORTEGA VILLALOBOS, Ana Isabel. Evaluation of the performance of portable radiographic processing boxes in light filtration. Acta odontol. venez [online]. 2006, vol.44, n.2, pp.159-164. ISSN 0001-6365.

The aim of this study was to evaluate the performance of portable radiographic processing boxes in the light filtration by the acrylic used in its construction, through the base-fog density of intraoral radiographic films. Films were exposed with a 4mm lead foil to obtain an unexposed area in the final radiograph, for base-fog density determination. Later they were exposed to the filtered light by three portable boxes during controlled time intervals and incident light, except a control group, which was not placed into the boxes. Also, a spectrophotometric analysis was performed on the acrylics of the boxes and a GBX-2 filter (Kodak) used in the safelight of conventional darkrooms. There was a statistically significant difference (p<0,05) between the mean base-fog density obtained from the films placed in the boxes and the control group, as well as a progressive increase of density related to the time that the films were exposed to the filtered the light. In comparison with the GBX-2 filter, the acrylic of the processing boxes has a greater transmittance. The filtered light by the radiographic processing boxes causes an increase of the base-fog density, related to the type of acrylic, the area that it covered in the box and the intensity of the incident light.

Keywords : processing box; base-fog density; radiographic film; radiographic processing.