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

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.

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 (T_p), 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.

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 T_p and T₁, while in group 2, none of the PAS points showed statistically significant differences when comparing T_p to T₁.

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.