Noise reduction effect on evaluation of apical root resorption in digital radiography: An in vitro study

The purpose of the current study was to evaluate noise reduction effect on apical root resorption evaluation in digital radiography. In the present experimental study, 60 extracted lower premolars with sound roots were used. The teeth were fixed in a dry human mandible for radiographic evaluation. Digital radiographs were taken before and after artificial external root resorption on the mesial side of the apical third by a #1⁄4 round bur and transferred to SCANORA software. Then all the radiographs were examined by one radiologist twice, with and without the option of noise reduction, with a one-week interval between the readings. The radiographs were scored in two groups: 0 and 1, without and with root resorption, respectively. Resorptions were measured by Williams probe and considered as the gold standard. Data collected from the digital radiographs were processed and the gold standard values were analyzed by SPSS 23 using McNemar and Cochran tests (α = 0.05). There were significant differences in frequencies of detection of root resorption between the three groups (standard, processed with the noise reduction option and processed without the noise reduction option) (p value < 0.001). There were no significant differences between the group processed with the noise reduction option and the group processed without the noise reduction option (p value = 0.774).Based on the results of this study application of noise reduction option in SCANORA software has no effect on the diagnosis of periapical lesions.