title: Assessment of simulated internal resorption cavities using digital and digital subtraction radiography: a comparative study.
abstract: OBJECTIVE
  To compare the diagnostic accuracy of digital radiography with that of digital subtraction radiography in the detection of simulated internal resorption cavities.
  
  
  METHODS
  Simulated internal resorption cavities of varying sizes were created using round burs in 18 single-rooted teeth with visible pulp chamber, which had been extracted from dentate dry mandibles and split into two halves in a mesio-distal direction. Resorption cavities were created in the buccal half of the root in the cervical, middle, and apical third. Digital radiographs were taken from three different horizontal view angles before and after the creation of the cavities. This process was followed by digital subtraction radiography to evaluate their detection. Seven experienced observers and all specialists in endodontics were asked to examine the digital and digital subtraction images for the presence of the cavities. The data were analyzed using SPSS 14.
  
  
  RESULTS
  The overall sensitivity of digital subtraction radiography was superior to digital radiography and with statistically better results for all cavities regardless of their location (cervical, middle, apical third) (P < 0.05). The detection of the cavities was affected by the root third in which they were located. Cavities in the apical third were more easily detected compared with those in the middle or cervical third of the root. Small-sized lesions (0.5 mm, 0.6 mm) in the middle and apical third were more frequent and more easily detected using subtraction imaging.
  
  
  CONCLUSIONS
  Digital subtraction radiography is superior to digital radiography for the detection and monitoring of the progress of internal root resorption.
authors.affiliation: Department of Endodontology, School of Dentistry, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Georgios
authors.initials: G
authors.lastname: Stephanopoulos
authors.forename: Georgios
authors.initials: G
authors.lastname: Mikrogeorgis
authors.forename: Kleoniki
authors.initials: K
authors.lastname: Lyroudia
mesh_terms: D002102:Cadaver; D006801:Humans; D008334:Mandible; D019252:Radiography, Dental, Digital; D012391:Root Resorption / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D013382:Subtraction Technique