Assessment of Virtual Digital Articulation Versus Hand-Articulation Accuracy for Occlusal Registration in Orthognathic Surgery (A Randomized Clinical Trial).

PURPOSE: To compare the accuracy of digital occlusal articulation versus hand occlusal articulation for orthognathic surgical planning. METHODS: This prospective, randomized clinical trial included 18 patients requiring orthognathic surgery, randomly assigned to a digital articulation group (n=9) or a hand articulation group (n=9). Linear displacements (X, Y, Z axes) at 5 maxillary and 5 mandibular landmarks and rotational errors (roll, pitch, and yaw) were measured postoperatively. Three blinded observers performed triplicate measurements. Interobserver reliability was assessed using intraclass correlation coefficients (ICC). Paired t tests were used for comparisons. Clinical tolerance was defined as <2 mm linear and <2 degrees rotational error. RESULTS: Interobserver reliability was excellent for both methods (ICC ≥0.98, P<0.001). In the maxilla, overall mean error was similar between digital (0.378±0.201 mm) and hand (0.353±0.155 mm) groups (P=0.367). In the mandible, the digital method showed significantly larger mean error (0.720±0.281 mm) than hand (0.430±0.268 mm) (P<0.001). Axis-specific differences in the mandible were significant for X (P=0.03), Y (P=0.006), and Z (P=0.005). Rotational errors were <0.5 degrees for all axes except mandibular pitch (0.47 degrees, P=0.04). The largest mean linear error was 1.03 mm (digital mandibular left molar), well below the 2 mm clinical tolerance. CONCLUSION: Digital occlusal articulation is as accurate as hand articulation in the maxilla and produces statistically larger but clinically acceptable errors in the mandible. Both methods are reliable and suitable for orthognathic surgical planning.