The purpose was to assess the accuracy and clinical validation of virtual planning and surgical template in mandible distraction osteogenesis. Patients with hemifacial microsomia were enrolled. Virtual planning and simulation were performed on three-dimensional models. Distraction was simulated on virtual model and the new morphology of the mandible was predicted. The position and direction of the distractor was determined to achieve the optimal morphology. The templates were designed based on virtual planning and manufactured using three-dimensional printing technique. The template is designed to assist the surgeon to perform the osteotomy and predrill the screw holes to guide the distractor position. The outcome evaluation was completed by comparing planned outcomes with postoperative outcomes. Linear and angular differences for the distractor was measured.

Inclusion Criteria:

• Patients who were scheduled to undergo mandibular DO via intraoral approach
• Patients who were scheduled to undergo CT scan as a part of their diagnosis and treatment
• Patients who agreed to participate in this study

Exclusion Criteria:

• Patients requiring more than one distractor of the mandible
• Patients with mandible defect
• Patients with previous mandibular trauma