Comparison of the postoperative and follow-up accuracy of articulator model surgery and virtual surgical planning in skeletal class III patients.

The aim of this study was to evaluate the postoperative and follow-up accuracy of using an intermediate occlusal splint between articulator model surgery (AMS) and virtual surgical planning (VSP) in double-jaw operations. Thirty skeletal class III patients were randomly allocated to have AMS or VSP. In the AMS group surgical planning was done through conventional articulator model surgery, and an intermediate occlusal splint made of acrylic resin was used. In the VSP group the surgical simulation was done virtually, and the same intermediate splint was used in the software and then fabricated using rapid prototyping technology. Preoperatively, one week postoperatively, and 1∼2-years later we obtained follow-up cone-beam computed tomographic (CT) images of each patient. Absolute linear differences between planned and actual outcomes, as well as planned and follow-up outcomes, were evaluated. There was no significant difference in either postoperative accuracy or follow-up accuracy between the methods, and there was no significant difference in the rate of skeletal relapse. Planning transfer by intermediate splint might therefore be the dominant factor in the final inaccuracies. The potentially greater accuracy of VSP may be realised with the help of new positioning devices instead of an intermediate splint.