The accuracy of surgical automatic robotic assisted implants placement in edentulous maxilla – an in vitro study

Abstract

<p><strong>Background</strong></p><p>The real-time surgical navigation system for improving the accuracy of implants placement has been tested and validated in various clinical cases. Most kinds of errors have been profoundly investigated to evaluate the accuracy. However, the application error associated with the surgeon is hard to eliminate and usually is negligible in the current studies. In order to avoid human error maximally, surgical automatic robot system can be introduced to eliminate it with successful outcome.</p><p><strong>Aim/Hypothesis</strong></p><p>To evaluate the accuracy of real time surgical navigation-robot system in placement of dental implants in the severely atrophic edentulous maxilla. In this model study, zygomatic implant (ZI), which is with a length of 50 mm was introduced to verify the reliability of this automatic robot system.</p><p><strong>Material and Methods</strong></p><p>To simulate the edentulous maxilla, six phantoms were fabricated according to rapid prototype with fused deposition modeling technology. Bone-anchored fixed titanium mini-screws (diameter 1.0 mm, length 9.0 mm, square cavity 1.0 mm) (CIBEI, Shanghai, China) were served as fiducial markers, and the phantoms then underwent CBCT scanning (i-CAT, Imaging Sciences International, Hatfield, PA+ 0.39 mm pixel+ 0.5 mm slice thickness). The DICOM data were transferred to a planning software (DentalHelper, Shanghai, China). Each phantom received two ZIs. The intraoral coronal entry points of implants were at or near the top of the alveolar crest at the level of the second premolar first molar region. Pre-operation planning was set up in surgical navigation system (OralImplantPlanningV1.0, Shanghai, China) and guided robot arm (Universal Robot UR6, Odense, Denmark) to perform automatically trajectory drilling procedure.</p><p><strong>Results</strong></p><p>The entry deviations, exit deviations and angle deviations of twelve 50 mm ZIs between preoperatively planned and postoperatively placed implants were measured in this study. The mean deviations of entry points was 2.34 ± 0.79 mm (range from 1.25 to 3.25 mm). The mean deviations of exit points was 2.57 ± 1.73 mm (range from 0.21 to 4.23 mm). The mean deviations of angle was 2.76 ± 1.39 degrees (range from 1.10 to 5.01 degrees).</p><p><strong>Conclusions and Clinical Implications</strong></p><p>Despite the limitations of the present study, the automatic robotic system could achieve accept planned-placed accuracy in ZIs placement.</p>