p w 1 c 2 fl a t t m d t s m u m ecent numerous clinical reports described well the enefit of distraction osteogenesis for facial bone deormities. For cases of severe midfacial retrusion, it ay be said that distraction osteogenesis in combinaion with Le Fort osteotomy is now one of the stanard procedures. Distraction osteogenesis for the axilla can be divided into 2 groups according to its nchorage: the external distractor, such as the RED ystem (Rigid External Distraction system: KLS-Martin P, Tuttlingen, Germany), and the intraoral distracor. In the latter group, many intraoral devices are nvolved, and the cylindrical distractor, such as Zurich ediatric Maxillary Distractor (KLS-Martin LP) is one f the well-known intraoral distractors for maxillary dvancement. Indeed, although these distractors have ome benefit, quite a smaller number of cases using nternal distractors has been reported in comparson with cases treated by the RED system. One of