Patient and
population (P) 		Healthy patients older than 18 years with severe dental malocclusion combine with dentofacial deformities necessitating orthognathic surgery.
Intervention (I) Three-dimensional virtual surgical planning of orthognathic surgery.
Comparator or
control group (C) 		Two-dimensional surgical planning of orthognathic surgery using cephalometric analysis and model surgery.
Outcomes (O) Primary outcomes included surgical accuracy of hard and soft tissue. Secondary outcomes included required treatment planning time, time in the operating theatre, intraoperative blood loss, intra- and postoperative complications, financial expenses, and patient-reported outcome measures.
Study design (S) Randomized controlled trials.
Focused question Are there any differences in the predictability and accuracy of orthognathic surgical planning using three-dimensional virtual surgical planning techniques compared with two-dimensional surgical planning?