Abstract
This article aims to determine the absolute accuracy of maxillary repositioning during
orthognathic surgery according to simulation-guided navigation, that is, the combination
of navigation and three-dimensional (3D) virtual surgery. We retrospectively studied
15 patients treated for asymmetric dentofacial deformities at the Oral and Maxillofacial
Surgery Unit of the S.Orsola-Malpighi University Hospital in Bologna, Italy, from
January 2010 to January 2012. Patients were scanned with a cone-beam computed tomography
before and after surgery. The virtual surgical simulation was realized with a dedicated
software and loaded on a navigation system to improve intraoperative reproducibility
of the preoperative planning. We analyzed the outcome following two protocols: (1)
planning versus postoperative 3D surface analysis; (2) planning versus postoperative
point-based analysis. For 3D surface comparison, the mean Hausdorff distance was measured,
and median among cases was 0.99 mm. Median reproducibility < 1 mm was 61.88% and median
reproducibility < 2 mm was 85.46%. For the point-based analysis, with sign, the median
distance was 0.75 mm in the frontal axis, −0.05 mm in the caudal–cranial axis, −0.35 mm
in the lateral axis. In absolute value, the median distance was 1.19 mm in the frontal
axis, 0.59 mm in the caudal–cranial axis, and 1.02 mm in the lateral axis. We suggest
that simulation-guided navigation makes accurate postoperative outcomes possible for
maxillary repositioning in orthognathic surgery, if compared with the surgical computer-designed
project realized with a dedicated software, particularly for the vertical dimension,
which is the most challenging to manage.
Keywords
computer-aided surgery - image-guided surgery - simulation-guided surgery - maxillofacial
orthognathic surgery - maxillofacial abnormalities
