[Micro- and macrodistraction of the jaw. A sure method of adding new bone].

Vertical distraction osteogenesis (VDO) has been developed by our study group to move dentulous and edentulous segments of the alveolar process vertically with a device in microplate-design. Besides these techniques of vertical distraction of the atrophic alveolar crest some further modifications as Micro- and Macro-distraction are available. Micro-distraction can be used in localised small defects of the alveolar crest with microplates and screws of 1.0 mm in diameter. In a pilot study we could treat 6 patients especially after traumatic bone loss of the alveolus. The lengths of the segments were 12.6 mm, the vertical distraction rate was 9.2 mm in average. Macro-distraction we call the distraction of the severely resorbed mandible in order to rebuild the vertical dimension of the weakened mandible. Vertical distraction osteogenesis of 13.6 mm was completed successfully in five patients with large segments of 119 mm lengths in average in a sandwich-technique. With a solid 2.3 basic plate a secure stability of the weakened mandible could be achieved. In contrast to bone transplantation an earlier mineralisation in the vertically distracted area could be seen by radiological examination and biopsy. We could insert dental implants in both pilot groups 3 months after distraction procedure. Main advantages of vertical distraction osteogenesis are: 1. No bone harvesting, 2. decreased resorption, 3. lower morbidity compared with conventional techniques, 4. lower infection rate and 5. feasibility to insert dental implants 3 months after distraction procedure, 6. gain of soft tissue.