Comparação da acurácia da tomografia computadorizada de feixe cônico e radiografia periapical digital na detecção de instrumentos endodônticos fraturados em molares mandibulares: um estudo ex vivo

Abstract

The main objective of this study was to compare cone-beam computed tomography (CBCT) and digital periapical radiography in the detection of separated endodontic instruments (SI) in fully filled root canals of mandibular molars. The second objective was to evaluate the impact of different milliamperages (mA) on the detection of SI in CBCT. Forty-two teeth were obturated, and 2 and 3 mm SI of three types of endodontic instruments (WaveOne® Gold; Reciproc® Blue; Protaper® Next) were inserted into the mesiobuccal canals of 30 of the test teeth. The KAVO OP 3D PRO scanner was used to acquire CBCT examinations. Images were acquired using fixed parameters of a field of view of 5 cm × 5 cm, 90 kVp, 85 µm voxel, and an exposure time of 8.7 s, and varying the mA from 6.3 mA to 9.0 mA. To acquire the digital periapical radiography images, the Focus Xray device was used, adjusted to 70 kVp, 7 mA and exposure time of 0.06 seconds, and the RVG 5200 sensor, size 2. RPD images were acquired in three different horizontal planes (orthoradial; mesioradial and distoradial, both with a 30° angle). All images were evaluated by three experts for the presence or absence of a SI, on a five-point scale. For CBCT, the multi-way ANOVA test with Tukey post-hoc tests was used, while for digital periapical radiography, the two-way ANOVA was used. To compare the performance of the imaging methods, a one-way ANOVA with Tukey post-hoc tests was used. The significance level was set at 5% (p= 0.05). In article 1, regarding the comparison of the performance of digital periapical radiography and CBCT, a statistically significant difference was observed for the Protaper® Next instrument (p< 0.05), with a worse area under the ROC curve (Az) value for CBCT. In article 2, in the CBCT evaluation, the Az in the detection of the WaveOne® Gold SI 3 mm size, was significantly higher than the other instruments evaluated, in all mA evaluated (p< 0.05). It was concluded that the most indicated diagnostic method for detecting fractured endodontic instruments is digital periapical radiography. Regarding CBCT, the variation in the tube current did not impact the visualization of the SI.