Accuracy of Minimally Invasive Laminate Veneer Preparations Using an Automated Dental Robotic System and Manual...

To evaluate the trueness and precision of minimally invasive laminate veneer preparations performed using a supervised automated robotic system compared with conventional freehand preparations.

Sixty identical 3D-printed maxillary models were randomly assigned to robotic preparation (RP) and manual preparation (MP) groups (n=30 each). A predefined CAD/CAM veneer preparation design for teeth 13-23 served as reference. In the RP group, preparations were performed using the Lupin robotic system under the supervision of six operators. In the MP group, six dental residents performed freehand preparations using silicone indices and depth-cutting burs. Preparations were digitized and compared with the virtual design by surface superimposition. Trueness was calculated as root mean square (RMS) deviation. Precision was quantified as between-operator variance. Group differences were estimated using a linear mixed model.

The MP group showed a mean RMS deviation of 0.266 ± 0.115 mm, whereas the RP group demonstrated substantially lower deviations of 0.060 ± 0.016 mm. Linear mixed model analysis estimated geometric mean RMS values of 0.242 mm (95% CI: 0.190 to 0.308) for MP and 0.058 mm (95% CI: 0.045 to 0.074) for RP, corresponding to a 76% reduction (ratio 0.24; 95% CI: 0.18 to 0.32; p < 0.0001). Between-operator variance was substantial in the manual group yet negligible in the robotic group, supporting independence of preparation outcomes from the supervising operator.

Robotic veneer preparation demonstrated significantly higher trueness and precision compared with manual techniques, resulting in highly standardized preparation outcomes and high preparation predictability.