Thesis (M.Sc.) - Cairo University - Faculty of Oral and Dental Medicine - Department of Oral ( Radiology and Diagnosis )

Thirty six human teeth were selected and a mesio-occluso-distal cavity (MOD) was prepared in each tooth and a round depression was prepared in the gingival floor of only one proximal box to simulate recurrent caries. The prepared teeth were divided equally and randomly into three groups according to final restorative material placed in the prepared cavity (12 teeth per group). The first group was restored with amalgam filling material ,the second with composite filling material ,and the third with ionomer filling material . Every tooth in the three groups was imaged by digital periapical radiography and CBCT. The resultant images were assessed for detection of simulated recurrent caries and radio-density of different restorations in relation to tooth structure Results: DDR was more accurate than CBCT in detection of caries under amalgam restoration. For composite restoration we found that DDR and axial CBCT images had higher accuracy than cross section CBCT images. While for glassionomer restored teeth, the axial and cross section CBCT images were more accurate than DDR. Using kappa to show inter observer agreement, there was statistically significant agreement range (0.39-1.00) between the two observers in detection of simulated recurrent caries under different restoration by using digital periapical radiograph, CBCT axial and CBCT cross sectional images. The difference in density between tooth structure and dental restorative materials in CBCT was very close regarding composite and amalgam restorations while for glass ionomer it was lower than them. In digital periapical radiography, the difference in density was highest in amalgam restorations followed by the composite restored teeth, while the lowest was in glassionomer restoration

Issued also as CD