Impact of motion artefacts and motion‐artefact correction on diagnostic accuracy of apical periodontitis in CBCT images: an ex vivo study in human cadavers. (11th June 2020) - Spin‐Neto, R.
Abstract: Aim: To assess the impact of motion artefacts and motion‐artefact correction on diagnostic accuracy of apical periodontitis (AP) in CBCT images. Methodology: Based on clinical and radiographic inspection of 40 formalin‐fixated human jaw specimens, 77 roots in 45 teeth (molars and premolars), with various disease and treatment state, were selected. The specimens were mounted on a robot simulating 3‐mm movement types (nodding, lateral rotation and tremor). CBCT images with and without (controls) movements were acquired in four CBCT units: without motion‐artefact correction in Cranex 3Dx, Orthophos SL 3D, and Promax 3D Mid, and with motion‐artefact correction in Promax 3D Mid and X1. Three observers blindly assessed (i) whether the images were interpretable and (ii) if AP was present (5‐step probability index). Histopathology provided the reference standard for presence of AP. Weighted Kappa statistics described inter‐observer agreement. Estimates of diagnostic accuracy were assessed by means of receiver operator characteristic (ROC) curve analysis. Area under the curve (AUC) provided a measure of accuracy, and paired‐sample AUC difference tests compared differences amongst the CBCT units and movement types. Results: Observer agreement was substantial for control images, moderate for motion‐artefact corrected images and fair for images without motion‐artefact correction. When movement was present, motion‐artefact correction reduced the percentage of images scored as noninterpretable or with uncertain disease state (score 3 in the 5‐step probability index). Control images were not perfectly accurate (both false‐positive and false‐negative results were present; AUC 0.750–0.799). Images acquired with movement and without motion‐artefact correction (AUC 0.541–0.709) were associated with significantly lower accuracy than control images ( P < 0.05). With motion‐artefact correction, accuracy was comparable to that observed in control images (AUC 0.732–0.790). Conclusions: Diagnostic accuracy of apical periodontitis in CBCT images was dependent on the presence of motion artefacts (i.e. lower accuracy associated with the presence of movement). Motion‐artefact correction systems positively influenced image interpretability and diagnostic accuracy.