In vitro carious lesion detection on D, E, and F-speed radiographic films

Radiography is considered as conventional method for caries diagnosis along with clinical examinations nowadays. Serious attempts have been made to increase diagnostic value of radiography and decrease x-ray radiation by developing different film types. The aim of present study was to assess diagnostic accuracy on detection of interproximal caries by three film types of D, E and F in in vitro conditions. In this diagnostic-invitro study, 75 human molars and premolars meeting study criteria were selected and assign in 25 blocks each having 3 teeth. The teeth were radiographed using three films of D, E and F in similar conditions using the same unit and processed similarly. Three blind and experienced radiologists assessed the radiographies and diagnosed caries. Then, the teeth were sectioned mesio-distally and examined by stereomicroscope by the magnification of ×10. The data were analyzed by diagnostic indices and analysis of variance. The sensitivity, specificity, accuracy, positive and negative predictive value of D film was 69.65%, 100%, 73.85%, 100% and 34.72% respectively. These criteria was respectively 71.30%, 94.44%, 74.43%, 98.14% and 33.94% in E film and 64.85%, 94.44%, 68.89%, 98.67% and 29.88% respectively. Analysis of variance test showed no significant differences to be found in caries depth considering film types and observers. The caries depth as determined by histopathological assessments did not show significant differences with the values determined by each observer in any film type as shown by paired t test. It seems that diagnostic criteria of three D, E and F films to be similar in the diagnosis of interproximal caries. Due to less radiation exposure, the use of F films are suggested for interproximal caries.