ABSTRACT
Because of over exposure or over development, occasionally radiographs will be darkened. For lightening and better diagnostic quality of radiographs, bleaching agents are used. One of the super proportional reducers is used in this research. The objective of this investigation was to determine the effect of reducing agent on diagnostic quality of extra oral darked radiograph. In this experiment, a human skull was used for radiographic examination. Two extraoral films were put in one casselle as double film. After exposure the two films were processed. One of the radiographs was used as control and the other film undergone bleaching procedure get light. The bleaching time was recorded, then films were washed in water. They were put in diluted developing solution [1/20 diluted]. The suitable color was selected by examiner. The time was recorded. Radiographs were washed in water, then they were put in diluted fixing solution [l/20 diluted]. They were washed and dried, and ready to interpret. 43 double film were used in this experiment. Radiologists and surgeon to evaluate diagnostic quality of definitive landmarks in sample and control films. They should give a grade from 1 to 5 for each chosen landmark on sample and control Radiographs. Grade 1 for the worst diagnostic quality. Grade 5 for the best diagnostic quality. The data were statistically studied to determine if there is a significant difference between the diagnostic quality of the control and sample film. According to wilcoxon test, there is meaningful different between the diagnostic quality of the controls and sample films. To improve diagnostic quality of extraoral darked radiographs we can use a super proportional reducing agent such as copper surface solution. This solution not only cause the reduction of density of darked radiographs but also it cause improvement of its diagnostic quality. The concentration of solution used for extraoral Radiograph is different from one that we use for intra oral radiograph