Objective: to know how much open access/open knowledge reference figures were available on motion artifacts in CBCT dentomaxillofacial imaging, and to describe and to categorize clinical variation of motion artifacts related to diverse types of head motion retrospectively observed during CBCT scanning time.
Material and methods: a search equation was performed on Pubmed database. We found 56 articles. The 45 articles were out of scope, and 7 articles were excluded after applying exclusion and inclusion criteria. Only 4 articles were finally freely accessible and selected for this review. Moreover, we retrospectively used our department CBCT database to search examinations with motion artifacts. We also checked retrospectively for radiological protocols as the type of motion artifact was described when occurred during the CBCT scanning time by the main observer. We had obtained the approval from the Ethical committee for this study.
Results: The accessibility of free figures on motion artifact in dentomaxillofacial CBCT is limited to 13 figures not annotated, and to one annotated figure presenting a double contour around cortex of bony orbits. We proposed to categorize the motion artifacts into three levels: low, intermediary, and major. Each level was related to: 1) progressive image quality degradation, 2) distortion of anatomy, and 3) potential possibility of performing clinical diagnosis. All 45 figures were annotated.
Conclusions: There exists a scarce open access literature on motion artifacts in CBCT. In our pictorial review we found that low level motion artifacts were more related to head rotation in axial plane (rolling). Rolling and lateral translation were responsible of intermediary level motion artifacts. Major level motion artifacts were created by complex motion with multiple rotation axes, multiple translation directions, and by anteroposterior translation. The main limitation of this study is related to retrospectively report empirical observation of patient motion during CBCT scanning and to compare these observations with motion artifacts found on clinical images. More robust methodology should be further developed using a virtual simulation of various types of head movements and associated parameters to consolidate the open knowledge on motion artifacts in dentomaxillofacial CBCT.