Effects of scan body exposure and operator on the accuracy of image matching of implant impressions with scan bodies

Statement of problem: Accurate image matching of the scan with the design of the scan body is essential to replicate the actual implant position in the software program. In situations where the scan part of the scan body is partially embedded in the gingival tissue, the influence of the scan image deficiency on the accuracy of image matching has not been clarified. Purpose: The purpose of this in vitro study was to examine the effects of scan body exposure and different operators on the accuracy of image matching of the scan body. Material and methods: Six groups with different scan body exposures (fully exposed, 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, and 2.5 mm less exposed) were digitized, and the scan images were transferred to a CAD software program, where the design of the scan body was matched to the scan image of each group. Based on the position of the scan body design, a virtual implant was created. The image matching process was performed 7 times for each group by 2 operators (N=84). The linear and angular deviations of the virtual implants were analyzed 3-dimensionally. Two-way ANOVA, equivalence, and concordance correlation coefficient statistics were used to verify the effects of scan body exposure and operator on the image matching. Results: As the exposure of the scan body was reduced, the deviations in implant positioning were significantly increased (P<.001). The concordance correlation coefficient indicated strong agreement between the 2 operators. Conclusions: Reduced exposure of the scan body significantly influenced the accuracy of implant positioning in the software program. Operator differences may not affect the accuracy of scan body image matching.