Vector control in transportation osteogenesis.

PURPOSE

To evaluate the ability to control vectors in the technique of transportation osteogenesis using 4 principles.

PATIENTS AND METHODS

Sixteen defects measuring approximately 30-180 mm were retrospectively evaluated. Vector control was attempted using a single or combination of the following principles: multiple linear vectors, exaggerated linear distraction ("sausage effect"), braced guided distraction, and reorientation osteotomies. Observations were made regarding the ability to create the desired vectors. Angular deviation from desired vectors was determined and recorded numerically by evaluating either submental vertex or occlusal radiographs, stereolithographic models, or digital radiographs. Radiographic evaluation of symmetry alone was not used to determine the desired vector because a more laterally displaced segment was desirable to maintain favorable facial balance when soft tissue deficiency was pronounced. A subjective evaluation scale was developed to supplement the numerical values.

RESULTS

Vector control primarily required the use of 2 or more principles. The most common combination was that of exaggerated linear distraction and reorientation osteotomy.

CONCLUSION

The use of multiple linear vectors, exaggerated linear distraction ("sausage effect"), reorientation osteotomies, and braced guided distraction greatly assisted the operator in achieving the goal of symmetrical reconstruction. Transportation osteogenesis may be considered an effective tool in the box to reconstruct patients. In cases in which vector control is achieved, the advantages of diminishing the volume of bone graft required or achieving final bony reconstruction can outweigh the disadvantages of the technique.