بررسي ميزان دقت راديو گرافي ديجيتال تفريقي در تشخيص تحليل خارجي مصنوعي ريشه در شرايط آزمايشگاهي

Accuracy of digital subtraction radiography in detection of artificial external root resorption (in vitro)

Introduction; External root resorption refers to the loss of cementum and/or dentin from the root of the teeth. 40% mineral loss occur in conventional radiographics but digital subtraction radiography is capable of localizing a lesion with only 1-5% mineral loss. This in vitro study aimed to determine the accuracy of digital subtraction radiography in diagnosis of simulated external root resorption.Methods and Materials: Ten premolar teeth with clinically intact roots were used were fixed in suitable place between the X-ray tube and CCD sensor. Direct digital radiographs were obtained before and after each lesion was created by 1/2, 1, 2, 4 and 6 round dental burs at facial and proximal surfaces; then digital subtraction images were obtained and observers evaluated all of the images and sensitivity and specificity and accuracy were calculated. Results were compared by % test (a = 0.05).Results: The sensitivity of digital subtraction and direct digital methods in detecting proximal defects were 97.34%) and 93.92% respectively (p value = 0.16). The sensitivity of digital subtraction and direct digital radiography in facial surfaces were 98% and 92.6%) respectively (p value = 0.03). The specificity of direct digital and subtraction methods in proximal surfaces were 91.92%o and 96.52% (p value = 0.08) and in facial surfaces were 91.92%) and 99.26%o respectively (p value = 0.002). The accuracy of digital subtraction radiography in detecting facial lesion was significantly superior to direct digital radiography.Conclusion: Digital subtraction radiography was superior to direct digital radiography in detecting small external root resorptive defects.