Accuracy of two-dimensional pharyngeal airway space prediction for bimaxillary orthognathic surgery

Purpose: The aim of this retrospective study was to evaluate the accuracy of two-dimensional (2D) virtual surgical planning (VSP) of pharyngeal airway space (PAS) in patients submitted to bimaxillary orthognathic surgery. Methods: This study was conducted with lateral cephalograms acquired through cone-beam computed tomography records of 33 patients, divided into group 1—patients submitted to maxillary advancement and mandibular setback (n = 17) and group 2—patients submitted to maxillomandibular advancement (n = 16). Records were taken 1 to 2 months prior to surgery, which was used to perform the 2D VSP (Tp), and 6 to 8 months after surgery (T1). In Dolphin Imaging software, the anteroposterior size of the PAS was calculated at the level of four craniometric points: A, occlusal plane (Mx), B, and pogonion (Pog). Two previously calibrated examiners performed these measurements. Statistical analyses were conducted using Kendall and t tests at a 5% level of significance. Results: There was a concordance between the two examiners at all points and times. In group 1, points A and B have statistically significant differences between the PAS measurements performed in Tp and T1, while in group 2, none of the PAS points showed statistically significant differences when comparing Tp to T1. Conclusions: 2D computer-based cephalometric prediction in Dolphin Imaging software offers a good orientation to professionals during the surgical procedure of bimaxillary surgeries since its use is considered clinically relevant in daily practice. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.