Resorbable bone distraction: current status and future directions

The pioneering work of Dr. Ilizarov defined the theory and practice of clinical bone distraction [ 1 Ilizarov G.A The tension- stress effect on the genesis and growth of tissues. I: The influence of stability of fixation and soft tissue preservation. Clin Orthop. 1989; 238: 249-254 PubMed Google Scholar , 2 Ilizarov G.A The tension-stress effect on the genesis and growth of tissues. II: The influence of the rate and frequency of distraction. Clin Orthop. 1989; 239: 263-269 PubMed Google Scholar ]. He laid the foundation for the future application of the principles of bone distraction to craniofacial surgery. In 1992, McCarthy et al began applying the principles of long bone distraction used in orthopedics to the craniofacial skeleton [ 3 McCarthy J.G Schreiber J Karp N et al. Lengthening the human mandible by gradual distraction. Plast Reconstr Surg. 1992; 89: 1-8 Crossref PubMed Scopus (1636) Google Scholar , 4 McCarthy J.G Distraction of the craniofacial skeleton. Springer-Verlag, New York1999 Crossref Google Scholar , 5 McCarthy J.G Distraction of the mandible: a ten-year experience. Semin Orthod. 1999; 5: 3-8 Abstract Full Text PDF PubMed Scopus (101) Google Scholar ]. He and his colleagues were able to demonstrate experimentally and clinically that distraction osteogenesis of membranous-derived bone was feasible, defining the scientific basis for craniofacial distraction and guiding early clinical applications. Distraction of the craniofacial skeleton offers many advantages over conventional advancement techniques, including gradual stretching of skin, muscle, and nerves, which minimizes the opposition to bone distraction and decreases the tendency for bony relapse of the advanced bony segments. Important neurovascular structures are slowly elongated, preserving continuity and function. In addition, distraction osteogenesis eliminates the need for bone grafting the osteotomy gaps, saving time and decreasing morbidity. Once the potential of this powerful new technique for “stretching bone” was fully realized, a frenzy of clinical and experimental work was unleashed. The early devices were adaptations of orthopedic instrumentation, used mostly in surgery of the hand, and had to be applied externally. Although these early external devices showed the feasibility of mandibular bone distraction, they had several drawbacks in clinical practice. The external pins that connected the devices to the underlying bone often became loosened, required constant pin site care, and were cumbersome for the patient. In addition, as the distraction proceeded, the pins tended to tract through the skin, leaving unacceptable scars. Multidirectional external devices gave a greater degree of directional control but had the many of the same disadvantages as uniplanar models [ [6] Molina F Mandibular distraction. Ann Chir Plast Esthet. 2001; 46: 505-511 Crossref Scopus (7) Google Scholar ]. These early devices were not applicable to maxillary distraction because of the early design constraints.