Frontal sinus mucoceles may present many years after traumatic injuries or surgical procedures involving the frontal bone, but have been rarely reported after fronto-orbital advancement. We describe a case of frontal sinus mucocele development in a 43-year-old patient with Apert syndrome who underwent fronto-orbital advancement as a child. This was treated with resection and free fibula osteomuscular flap reconstruction. Computer-aided design and manufacturing techniques were used to virtually plan the procedure and guide the osteotomies intraoperatively. Follow-up at 1 year postoperatively revealed no evidence of recurrence.