The objectives of this study were (i) to evaluate different fracture mechanisms for orbital floor fractures and (ii) to measure forces and displacement of intraorbital tissue after orbital traumata to predict the necessity of strength for reconstruction materials. Six fresh frozen human heads were used, and orbital floor defects in the right and left orbit were created by a direct impact of 3.0 J onto the globe and infraorbital rim, respectively. Orbital floor defect sizes and displacement were evaluated after a Le Fort I osteotomy. In addition, after reposition of the intraorbital tissue, forces and displacement were measured. The orbital floor defect sizes were 208.3 (SD, 33.4) mm2 for globe impact and 221.8 (SD, 53.1) mm2 for infraorbital impact. The intraorbital tissue displacement after the impact and before reposition was 5.6 (SD, 1.0) mm for globe impact and 2.8 (SD, 0.7) mm for infraorbital impact. After reposition, the displacement was 0.8 (SD, 0.5) mm and 1.1 (SD, 0.7) mm, respectively. The measured applied forces were 0.061 (SD, 0.014) N for globe impact and 0.066 (SD, 0.022) N for infraorbital impact. Different fracture-inductive mechanisms are not reflected by the pattern of the fracture. The forces needed after reposition are minimal (∼0.07 N), which may explain the success of PDS foils [poly-(p-dioxanone)] and collagen membranes as reconstruction materials.
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From the *Institute of Anatomy, †Dental School, Department of Prosthodontics, Propaedeutics and Dental Materials, and ‡Department of Oral and Maxillofacial Surgery, Christian-Albrechts University Kiel, Kiel, Germany.
Received October 17, 2011.
Accepted for publication January 2, 2012.
Address correspondence and reprint requests to Falk Birkenfeld, DMD, Institute of Anatomy, Christian-Albrechts University Kiel, Otto-Hahn-Platz 8, 24118 Kiel, Germany; E-mail: firstname.lastname@example.org
The authors report no conflicts of interest.