Methods
Ten novices (fourth-year dental students), and ten experts in prosthodontics performed a crown preparation task with a haptic VR that provided force feedback to the operating tool while interacting with the virtual tissue/organ. For each step of the crown preparation, the system automatically recorded data associated with performance process including time to task completion (T), force used (F), and angulations (A) of the bur. The preparation outcome (O) scores were graded by an expert in the field. An independent t-test was conducted on all dependent variables (F in x-, y-, z-axes; A in zy, zx, xy planes; T and O) between experts and novices.
Results
Experts performed significantly better than novices (p < 0.05) as shown by greater O. Expert T was significantly less than that of novices (p < 0.05). Instrument A as well as F used were significantly different in almost all preparation steps in both groups (p < 0.05).
Conclusion
This study clearly demonstrated the ability of outcome and process measures to distinguish between novice and expert performance in crown preparation using a haptic VR system.