Mandibular Lengthening: Frankfurt System
3 of 45

Cornelius M. Klein, MD, DMD, PhD

The Bi-Directional Distractor  

The "Frankfurt Craniofacial Distraction System" for mandibular lengthening was developed in cooperation with the medical instrument manufacturer Normed (Tuttlingen, Germany). The Bi-Directional Distractor consists of two limbs connected to an angulation joint. The half pins are mounted to a mobile slide on each limb. A third pin holder is mounted to the angulation piece. The slides are driven on a geared rod, which is calibrated in millimeters. The angulation piece allows controlled rotation of the two limbs from 180° to 90° positions. Radial grooves on the inner surface of the angulation joint apply slight friction, thereby avoiding uncontrolled angular changes between the two limbs.

Fig. 6.1.3.1. Diagram demonstrating structure of the Bi-Directional Distractor.