Haptic bilateral teleoperation system for free-hand dental procedures
Authors: Lorenzo Pagliara, Vincenzo Petrone, Enrico Ferrentino, Andrea Chiacchio, Giovanni Russo
Organizations: Department of Information Engineering, Electrical Engineering and Applied Mathematics (DIEM), University of Salerno, 84084 Fisciano, Italy · Specialization School in Oral Surgery, University of Naples Federico II, 80138 Napoli, Italy
Free-hand dental procedures are typically repetitive, time-consuming and require high precision and manual dexterity. Robots can play a key role in improving procedural accuracy and safety, enhancing patient comfort, and reducing operator workload. However, robotic solutions for free-hand procedures remain limited or completely lacking. To address this gap, we develop a haptic bilateral teleoperation system (HBTS) for free-hand dental procedures (FH-HBTS). The system includes a mechanical end-effector, compatible with standard clinical tools, and equipped with an endoscopic camera for improved visibility of the intervention site. By ensuring motion and force correspondence between the operator's and the robot's actions, monitored through visual feedback, we enhance the operator's sensory awareness and motor accuracy. Furthermore, to ensure procedural safety, we limit interaction forces by scaling the motion references provided to the admittance controller based solely on measured contact forces. This ensures effective force limitation in all contact states without requiring prior knowledge of the environment. The proposed FH-HBTS is validated through a technical evaluation and an in-vitro pre-clinical study conducted on a dental model under clinically representative, yet simplified, conditions. The results show that the system improves the naturalness, safety, and accuracy of teleoperation, highlighting its potential to enhance free-hand dental procedures.
Algorithm 1 Eye-hand coordination mapping and scaling
Fig. 6: Integrated mechanical end-effector for free-hand procedures. Visible in the left side of the figure is also one of the dental models used in the experiments.
Fig. 7: Comparison between the conditional expectation of the interaction force in all three scenarios.
Fig. 8: Eye-hand coordination assessment.
Group 1
Group 2
Group 3
K–W test
Mean ± STD
Mean ± STD
Mean ± STD
χ2
p
NASA-TLX
Mental Demand
30.00±27.57
51.43±15.74
36.67±23.38
2.91
0.23
Physical Demand
26.67±24.22
20.00±11.55
16.67±19.66
0.70
0.70
Temporal Demand
36.67±23.38
42.86±13.80
36.67±15.06
0.52
0.77
Performance
43.33±8.17
37.14±13.80
33.33±10.33
2.42
0.30
TABLE I: Summary of the NASA-TLX and 5-point Likert scale questionnaire responses and SUS scores. NASA-TLX subscales are reported on their native 0–100 scale; the Overall row is the average of the six subscales. Likert-scale items are reported on a 1–5 scale. For the Ergonomics item, the scale was anchored relative to the participant’s experience of manual execution, so that 3 denotes the neutral midpoint (perceived parity with manual practice), while scores above/below 3 denote a perceived improvement/deterioration relative to manual practice.
Department of Automation, Tsinghua University, China · Department of Mechanical and Process Engineering, ETH Zürich, Switzerland · Tsingscribe Medical Ltd., China +1
Rochester Institute of Technology, Rochester, NY · TikTok Pico Lab, San Jose, CA · The Hong Kong University of Science and Technology, Guangzhou, China