Evaluation of dynamic computer-assisted implant placement accuracy by means of a novel digital method: a feasibility clinical study

To present a novel digital method to evaluate dynamic computer-assisted implant surgery (dCAIS) accuracy comparing digital implant planning to real implant position. Twenty patients in need of implant supported single unit-crowns (SUC), were consequently treated following a standardized digital protocol encompassing (1) a diagnostic digital intra-oral scan (IOS), (2) a cone beam computed tomography (CBCT), (3) 3D digital implant planning, (4) dynamic navigated implant placement (X-Guide, X-Nav Technologies, LLC, Lansdale, PA, USA) and (5) a post-operative IOS with the scan body in situ. Implant position accuracy was evaluated by superimposing the post-operative IOS with the pre-operative digital planning and calculating the resulting angular deviation (o), global head deviation (mm) and global tip deviation (mm). From the original 30 installed implants, 29 could be analyzed. All surgical procedures were successfully completed without any complication. The calculated mean angular deviation was 4.50° ± 2.59°, while the mean deviation at the implant head was 1.18 ± 0.52 mm. Finally, the global tip deviation was 1.43 ± 0.78 mm. Flapless implant placement was significantly associated with a reduction in both head and tip linear deviations (p = 0.026; p = 0.007), as well as with a significant reduction in angular deviation (p < 0.001). Implants placed in the anterior region showed a mean statistically significantly higher deviation at the implant head compared to those in posterior sites (difference: 0.39 mm; p = 0.043). Despite its limitations, the proposed digital method does represent a promising and patient friendly approach to evaluate dCAIS accuracy. The proposed digital method represents a promising workflow for the evaluation of dCAIS implant placement avoiding the need of post-operative radiations.