Monobloc and facial bipartition distraction with internal devices.

Abstract

Distraction osteogenesis (DO) permits gradual lengthening of the craniofacial skeleton. With the advent of new internal devices, monobloc (M) and facial bipartition (FB) DO are feasible. The rationale behind M and FB distraction is (1) gradual advancement of the M segment is not associated with a substantial retrofrontal dead space; (2) because 5 to 7 days elapse prior to distraction, the nasofrontal opening, in theory, is allowed to remucosalize; (3) gradual expansion of the soft tissues takes advantage of skin creep, potentially limiting relapse; (4) the procedure appears to be less invasive with decreased blood loss and operative time, enabling its use in infants; (5) overdistraction may eliminate or reduce the frequency of subsequent procedures; and (6) the procedure may be combined with FB and skull vault remodeling to provide excellent results in more complex craniofacial dysostosis problems. Five children underwent M advancement (N = 3) and M with FB (N = 2) at 9 months to 5 years of age to correct functional abnormalities such as corneal exposure, increased intracranial pressure, and apnea, as well as severe craniofacial disfigurement. Each patient underwent from 22 to 30 mm of distraction with the Modular Internal Distraction (MID) system, developed by the first author (SRC). There was one infection late in the series along the DO cable track. There were no cases of epidural abscess. In conclusion, MDO, with and without FB, appears to be a safe and effective technique for transcranial frontofacial advancement. The morbidity of the procedure appears to be less than that of conventional M advancement.