1.3mm Pediatric Curvilinear Distractor

Carl-Peter Cornelius

The 1.3 mm Pediatric Curvilinear Distractor (Fig 1) was developed to address an unmet clinical need for distraction devices in pediatric patients less than 1 year old. The 2.0mm system is indicated only for adults or pediatric patients over one year of age.

The new 1.3 mm Pediatric Curvilinear Distractor system (Fig 2) is an internal distraction osteogenesis device that gradually advances the mandible along a curved trajectory of distraction. As with the previously developed 2.0 mm Curvilinear Distractor, the 1.3 mm is indicated for correction of congenital deficiencies or posttraumatic defects on the mandibular body and ramus, where gradual bone distraction is required. This 1.3 mm pediatric version is intended for patients four years of age and younger.

The aim of curvilinear distraction is twofold: to lengthen the mandible in both vertical and horizontal planes, and to close, or avoid creating, an open bite.

In order to adapt the existing distractor's design to the smaller anatomy of pediatric patients, it was necessary to reduce the overall size of the device both in terms of profile (from 7.5 mm to 5.5 mm) and track width (from 4.25 mm to 3 mm). The device was named 2.0mm Curvilinear Distractor (Fig 3). Other modifications include the footplate design, which changed to a mesh pattern to allow for the insertion of more screws in a smaller area of bone, and the distractor acceptance of 1.3 mm diameter bone screws.

The device allows advancement of up to 35 mm, leaving the surgeon the option of cutting and crimping the track if less advancement is required. Existing tools, such as cutters and crimpers, were slightly modified to be able to work with both sized distractors: 2.0 mm and 1.3 mm (Fig 4).

A functional stop is created by a track crimp to avoid undesired device disassembling (Fig 5). The distractor is made of titanium molybdenum, is for single use only, and has left and right assemblies available in different radii of curvature (30 mm, 40 mm, 50 mm, 70 mm, and 100 mm), as well as a straight version.

All distractors accept removable extension arms (Fig 6), which move the point of activation to a location that is easily accessible with the activation instrument.

One full rotation of the activation instrument (Fig 7) equals 1.0 mm of distraction per day (one half turn twice daily), and is recommended to prevent premature consolidation. In young patients a distraction rate of 1.5 to 2.0 mm per day could be considered.

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