Abstract: Objective　 To verify the feasibility and reliability of digital wafers in bimaxillary surgery for skeletal Class III malocclusion patients and compare the accuracy of digital wafers with traditional wafers. Method Forty patients with skeletal Class III malocclusion who performed bimaxillary surgery were divided into traditional wafer group and digital wafer group, 20 in each group. In ProPlan CMF 3.0 software, the linear distance from 14 hard tissue measurement points to three reference planes was measured and the angles between the three selected measurement planes and the three reference planes were measured. Simulative and real difference between traditional wafer group and digital wafer group was compared. Result The difference between simulative and real linear measurement indexes of digital wafer group was less than 2 mm, and the difference of angle measurement indexes was less than 4°. L1-Y, GoL-X, GoL-Y, GoR-X, GoR-Y, CoL-Y and CoR-Y in digital wafer group had statistical differences between simulation and reality (P≤0.042). There were statistical differences between the traditional wafer group and the digital wafer group in L6L-X, GoR-X, LOP-X, MP-X, GoL-Y and MP-Z (P≤0.046). Conclusion The application of digital wafers in bilateral surgery is safe and reliable, and is more accurate and effective than traditional wafers.

Key words: Skeletal class III malocclusion, Bilateral surgery, Three-dimensional cephalometric measurement, Digital wafers