[Osteosynthesis in the mid-face and forehead area]

In the beginning of the development of facial osteosynthetic techniques only relatively thick plates were available. Since then various mini- and micro-plating systems were developed for the midfacial and forehead regions. As so many different systems with different sizes are available, it is important to know which systems are appropriate for which indications. Therefore, the aim of this study was to add knowledge to some aspects of the differential indications of different systems for the middle and upper facial regions.

1. The pull-out forces of seven different mini- and microscrews were measured. 2. The thicknesses of the facial bone were measured at 11 different points in 10 skulls. 3. The clinical experiences of midfacial and upper facial osteosynthesis in 45 patients were summarised.

The pull-out forces increase with increasing bone- and screw-thickness and also substantially depend on the design of the screws. Although the bone thicknesses in the mid and upper facial region vary considerably, all investigated regions are suitable for osteosynthesis. In none of our patients any complication occurred that was related to the osteosynthesis.

Microsystems with screw diameters of 0.8 mm (Howmedica) are suited for fractures of the nasoethmoidal complex. Providing the same thickness as the microplates the Panfixsystem (Howmedica) offers a better holding strength especially when using the 1.3 mm screws, and is easier to handle. For stabilising fractures of the zygoma, which might dislocate postoperatively due to the pulling force of the masseteric muscle, we still feel that the miniplating technique with compression is the method of choice.