2000 Volume 63 Issue 1 Pages 33-37
We compared the perceived quality of panoramic dental images obtained using both digital charge-coupled devices(CCD)and analog radiographic film to determine the ideal clinical exposure conditions.Images were exposed on an averaged man phantom using same machine at 60, 70 and 80kV and 2, 4, 6, 8 and 10mA.Many clinicians have noted that the visual characteristics of images made using digital radiography are different from those of film based images.We selected 15 digital radiographs and made a computer program that allowed the observers to manipulate the contrast and brightness of the image.The diagnostic image quality was evaluated by six observers, five of whom were oral radiologists, and the other a postgraduate student.The observers were asked to evaluate 20 points on both the digital and analog images.We found that the best digital radiographic images were exposed at 70kV / 8mA, and the best analog images were at 70kV / 6mA.However, the digital images deteriorated at tube currents above 8mA for all tube voltages.The observers found no difference between the two methods for the 20 anatomical points evaluated.These results indicate that the digital system is a useful diagnostic tool that also reduces radiation exposure.We concluded that digital images are clinically equivalent to conventional film images for panoramic dental radiography.
