Mandibular midline distraction osteogenesis.

In orthodontics, bone structure, its density and dimensions play an essential role by explaining limitations in magnitude, size and extent of tooth movement. Severe anterior crowding is one of the most frequently encountered dental malocclusions. Its therapy is mostly limited by lack of basal and alveolar bone and it often involves tooth extractions. Mandibular midline distraction osteogenesis is a method of natural bone generation and also a treatment option to achieve space regaining in a much-reduced lower jaw with distinctive frontal place deficit and severe anterior crowding, without sacrificing permanent teeth. McCarthy and Guerrero were of the first researchers reporting on this method applied on human lower jaws and they increased clinical interest in this approach. Although this method has been clinically used ever since, many questions concerning effects on bone regeneration speed, bone quality, tooth movement into regenerated area, periodontal health and long-time stability of treatment outcomes have not been sufficiently investigated. This overview should present the current clinical and biological state of knowledge about bone gain and tooth movement through regenerate bone. Furthermore it should encourage interest in further research on this topic.