STUDY OF EFFECTIVE TIME OF UNDILUTED FIXINGSOLUTIONS INLIGHTENING OF THE HIGH DENSITY PERIAPICAL RADIOGRAPHS
Abstract
Introduction: Dental radiographs are occationally too dark because of different reasons such as over exposure, high concen-tration of developing solution and over development.
Different chemicals are used to lighten these radiographs. In this research the undiluted fixed solution for the first time are tested and efficiency time of this solution in reducing the density of dark radiographs were evaluated.
Method: Use of a dry mandible containing some teeth and 98 E speed periapical radiographs were prepared as foolow: A film wasexposed with 0.4 S... as positive control (ideal). 97 films were exposed with 1.8 S (dark and unreadable). Out of 97, one radiograph kept as positive control and remaining films prepared for study. All of radiographs developed and fixed with automatic processor in the same conditio. Out of 96 dark radiograph, 3 was used for pilot study and inserted in the undiluted fixing solution in different time. (2.5, 3 and 3.5 hrs). The result of pilot study showed that aii3 radiographs showed reductionin density and radiographs with her reduction time was closest to positive control for density and diognostic quality and radiograph with 2.5 hrs reduction time and 3.5 hre became darker and lighter as compared to positive control. The remaining 93 high density radiographs were divided into 3 groups, 31 in each group (group 1,2 and 3) first group 2.5 hrs, second 3 hrs and the third group 3.5 hrs were kept in undiluted fixed solution. for this, disposable glasses were used and in each glass a radiograph were inserted. The research time was spring and the temperature was about 2609 (without coolant).
Evaluation of radiographs: For evaluation of radiographs 2 methods were used: First method used was: Densitometry: By this method the density of total lightened radiographs, positive control and negative control were determined. Another method was determined diagnostic quality of radiographs visually by radiologists, throng this way: Special application form were prepared and requested their opinion about the result of radiographs by observation and comparing them with positive and negative radiographsand give them score from Ito5.
Result: The result of densitometry showed that the density of all radiographs after inserting in undiluted fixing solution were decreased. All dentists who compared the lightened radiographs with positive control and negative control has the same opinion that: The radiographs have desirable diagnostic quality.
Discussion: Totally the undiuted fixed solution is a suitable solution for decreasing the density and giving the diagnostic quality to dark radiographs and prevents reexposure of patients and decreases the extra costs.
Different chemicals are used to lighten these radiographs. In this research the undiluted fixed solution for the first time are tested and efficiency time of this solution in reducing the density of dark radiographs were evaluated.
Method: Use of a dry mandible containing some teeth and 98 E speed periapical radiographs were prepared as foolow: A film wasexposed with 0.4 S... as positive control (ideal). 97 films were exposed with 1.8 S (dark and unreadable). Out of 97, one radiograph kept as positive control and remaining films prepared for study. All of radiographs developed and fixed with automatic processor in the same conditio. Out of 96 dark radiograph, 3 was used for pilot study and inserted in the undiluted fixing solution in different time. (2.5, 3 and 3.5 hrs). The result of pilot study showed that aii3 radiographs showed reductionin density and radiographs with her reduction time was closest to positive control for density and diognostic quality and radiograph with 2.5 hrs reduction time and 3.5 hre became darker and lighter as compared to positive control. The remaining 93 high density radiographs were divided into 3 groups, 31 in each group (group 1,2 and 3) first group 2.5 hrs, second 3 hrs and the third group 3.5 hrs were kept in undiluted fixed solution. for this, disposable glasses were used and in each glass a radiograph were inserted. The research time was spring and the temperature was about 2609 (without coolant).
Evaluation of radiographs: For evaluation of radiographs 2 methods were used: First method used was: Densitometry: By this method the density of total lightened radiographs, positive control and negative control were determined. Another method was determined diagnostic quality of radiographs visually by radiologists, throng this way: Special application form were prepared and requested their opinion about the result of radiographs by observation and comparing them with positive and negative radiographsand give them score from Ito5.
Result: The result of densitometry showed that the density of all radiographs after inserting in undiluted fixing solution were decreased. All dentists who compared the lightened radiographs with positive control and negative control has the same opinion that: The radiographs have desirable diagnostic quality.
Discussion: Totally the undiuted fixed solution is a suitable solution for decreasing the density and giving the diagnostic quality to dark radiographs and prevents reexposure of patients and decreases the extra costs.