Additional distraction osteogenesis after conventional fronto-orbital advancement.

In the conventional fronto-orbital advancement method, there is a limit to advancement because of scalp skin tension and an absence of a supraorbital bar fixating point. In a case of insufficient advancement after the primary operation, a secondary re-advancement must be performed. In such a condition, additional fronto-orbital advancement by distraction osteogenesis has proved to be very useful. The authors used additional distraction osteogenesis in three infant cases: two of nonsyndromic craniosynostosis and one of Apert's syndrome. They were able to perform these operations safely using their original internal devices. Distraction was started 3 days after the operation. The rate of advancement was 0.5 to 1.0 mm per day. The distraction distances ranged from 16 to 22 mm. They were able to gain enough advancement in all three cases. A reoperation of a fronto-orbital advancement is more difficult than the primary operation because of possible infection, much loss of blood, low blood supply to advanced bones, a tendency of advanced bones to relapse, increased scalp skin tension, and the existence of bone defects. In these poor conditions, distraction osteogenesis has many advantages: good vascularization, no relapsing, a low infection rate, and no need for bony fixating points in the bone defects. Although it is necessary to have a secondary operation to remove the devices and prolonged hospitalization is required, the disadvantages are far outweighed by the many advantages when performing additional fronto-orbital advancement.