A Comparative Study of Diagnostic Accuracy of Cone Beam Computed Tomography and Intra Oral Digital Radiography Phosphor Storage Plates in Detecting Strip Perforation in Endodontically-Treated Teeth

Perforation impairs the prognosis of endodontic treatments, so, timely and accurate diagnosis is important. For this purpose, various radiographic diagnostic tools have been studied to select the method that has the least complications and helps in making the most accurate diagnosis. This study aimed to compare the accuracy of cone beam computed tomography (CBCT) and intra oral digital radiography phosphor storage plates (PSP) in detection of strip perforation in endodontically treated teeth.

In this experimental study, 124 extracted mandibular molar teeth were selected. Standard access cavities were prepared, then cleaning and shaping in mesiolingual canal were performed by Protaper Gold rotary instruments to size F2. Next, the teeth were randomly divided into four groups (n=31 per group). Control group was left with no perforation while distal wall of mesiolingual canal in other three groups were perforated using Gates Glidden #2 and 3 in 1-3 mm below the furcation region in three ranges; 0-0.5, 0.5-1, and 1-1.5 mm. Electronic Digital Caliper was used to confirm the accuracy of the size of perforations. Obturation was performed in mesiolingual canals employing sealer and gutta-percha by lateral condensation technique. The teeth were then randomly placed in bovin ribs. PSP and CBCT images of all samples were examined by two oral radiologists and data were analyzed in SPSS.

The sensitivity, specificity, and accuracy of PSP were 90.8%, 88.7%, and 90% and those of CBCT were 95.7%, 72.6%, and 90%, respectively. Sensitivity of CBCT was found to be significantly higher than that of PSP (P<0.01), while specificity of PSP was significantly higher than that of CBCT (P<0.01).

CBCT is the most reliable technique when it is not possible to detect strip perforation in filled root canals by conventional periapical digital imaging systems.