The accuracy of orthodontic imaging management software in virtual simulating orthognathic surgery

Objective To evaluate the accuracy of surgical simulation in orthognathic surgery and find a reliable method for surgical simulation. Methods 12 patients undergoing combined orthodontic-orthognathic surgical treatment were selected. The CBCT data, scanned dental data and 3D facial photo were collected before surgery. The orthodontic-orthognathic surgery was simulated using orthodontic imaging management software (constructing 3D model, setting up coordinate system, defining osteotomy line, defining landmarks, 3D analysis and designing, 3D printing and et al.) The digital occlusal splint was completed and applied to orthognathic surgery. The skull base area was selected as the reference for superimposition of CBCT to verify the changes of the main landmarks in three dimensions. The preoperative and postoperative error of the main landmarks was calculated. Paired samples t test was used to verify the consistency between the simulation aided by the software and the result of actual surgery. Results The 3D printed Occlusal splint designed using the software was stable and accurate for occlusion and jaw location. The main landmarks (ANS, A, U1, PNS, L1, B, Pog, Me) showed no statistical difference between the preoperative predicted movements and actual operative movements after three dimensional superimposition (P>0.072). The errors on three dimensions were between 0.57 mm-1.53 mm. Conclusions Surgical simulation in orthognathic surgery designed using the orthodontic imaging management software was applicable and the 3D printed occlusalsplint was accurate enough for orthognathic surgery Key words: Orthodontic imaging management software; Orthodontics-orthognathic treatment; Occlusal splint