The aim of this chapter is to review literature reporting on the use of internal distraction osteogenesis and rigid external distraction osteogenesis and to determine the biomechanical effects of internal distractors in the treatment of maxillary hypoplasia, especially in patients with cleft lip and palate (CLP), and compare the results with non-cleft patient. The standard osteotomy used for distraction osteogenesis of the hypoplastic maxilla is LeFort I. An advancement of more than 10 mm in patients with no cleft and 6 mm in patients with CLP is beyond the limit of LeFort I osteotomy, and in such cases distraction osteogenesis for advancement of the maxilla can be used. Distraction osteogenesis (DO) is a biological process involving the formation of new bone between viable bone segments that are gradually separated by incremental traction. The external and internal usage of distraction osteogenesis in the treatment of maxillary hypoplasia in patients with cleft lip and palate is a reliable, reproducible and stable alternative method to conventional one-step LeFort I advancement techniques. Biomechanical evaluation of internal maxillary distraction osteogenesis produces mathematical results to help the surgeon and the orthodontist to understand better the therapeutic effects on the maxillofacial bones and sutures of the craniofacial system.
Part of the book: Advanced Techniques in Bone Regeneration