Comparing Accuracy of Cylindrical and Tapered Implants Using Autonomous Robotic System: A Randomized Controlled Trial

OBJECTIVES: This study aimed to systematically evaluate the effect of implant shape (cylindrical versus tapered implant) on the accuracy of placement using an autonomous robotic system in patients with single-tooth loss. MATERIALS AND METHODS: Forty individuals with a single missing tooth were randomly assigned to receive either a cylindrical implant (CI) or a tapered implant (TI). All implants were digitally planned and placed with an autonomous robotic system. The primary outcomes were coronal, apical, and angular deviations. Secondary outcomes included surgery time and insertion torque value (ITV). RESULTS: A significantly smaller apical deviation was observed in the TI group (0.70 ± 0.23 mm) compared to the CI group (0.91 ± 0.38 mm; p < 0.05), and there was statistically smaller angular deviation in the TI group (1.18° ± 0.46°) than the CI group (1.76° ± 1.02°; p < 0.05). Furthermore, the implantation time was also significantly shorter in the TI group (5.88 ± 2.34 min) than the CI group (9.84 ± 5.45 min; p < 0.01), and the TI group (24.33 ± 11.47 N cm) was statistically lower than the CI group (31.75 ± 10.17 N cm; p < 0.05) in ITV. No statistically significant differences were observed regarding coronal deviation and osteotomy duration between the two groups. CONCLUSIONS: Considering the study's limitations, both implant shapes were automatically placed with clinically acceptable accuracy. Tapered implants, however, demonstrated statistically superior apical and angular positioning accuracy and a more efficient insertion process without compromising primary stability. These findings warrant further investigation to confirm their clinical relevance. TRAIL REGISTRATION: ChiCTR2500105588.