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Published on: February 23, 2024
Accuracy of autonomous robotic buccal alveolar bone reduction for anterior crown lengthening: An in vitro study
Yalin Zhan1, Huidan Shen1, Ye Han1
1First Clinical Division, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, PR China; Peking University Hospital of Stomatology Sanya Division (Sanya Stomatology Center).
Objectives:
To evaluate the planned-to-actual accuracy of autonomous robotic buccal alveolar bone reduction for anterior crown-lengthening surgery in vitro.
Methods:
Six standardised maxillary anterior typodont models were digitised using intraoral scanning and cone-beam computed tomography. Buccal reduction volumes were planned for teeth 13-23 (36 tooth-level reduction volumes) and executed by an autonomous robotic system. The planned and actual datasets were compared for apical midpoint deviation (AMD), coronal mesial point deviation (CMD), coronal distal point deviation (CDD), directional components, buccal surface deviation, lingual depth deviation, root surface clearance, and reduction volume deviation. Subgroup and correlation analyses were exploratory.
Results:
AMD was 0.391 ± 0.243 mm, CMD was 0.598 ± 0.372 mm, and CDD was 0.506 ± 0.292 mm. Planned area coverage was 92.765 ± 4.908%, actual area agreement was 85.974 ± 7.145%, and relative area difference was 8.627 ± 10.891%. The relative volume difference was -5.773 ± 22.531%. Directional deviations differed significantly among the three point locations along the X and Y axes (both P < 0.001), but not along the Z-axis (P = 0.841). The root mean positive distance was 0.558 ± 0.177 mm. Negative root-distance values occurred in 4 of 36 tooth-level reduction volumes from three models, with maximum negative root distances ranging from -0.0106 to -0.6470 mm.
Conclusions:
Autonomous robotic buccal alveolar bone reduction reproduced the planned crown-lengthening geometry with submillimetre point deviations in this in vitro model, demonstrating the potential of this approach to enhance surgical precision. Further clinical studies are needed to validate its accuracy.
Clinical Significance:
In this in vitro study, autonomous robotic buccal alveolar bone reduction for anterior crown lengthening achieved submillimetre accuracy. These findings suggest the potential of this approach to enhance surgical precision.