Forces charging the orbital floor after orbital trauma.
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) mm(2) for globe impact and 221.8 (SD, 53.1) mm(2) 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.
Institute of Anatomy, Department of Prosthodontics, Christian-Albrechts University Kiel, Kiel, Germany. f.birkenfeld@anat.uni-kiel.de
Falk
F
Birkenfeld
Martin
M
Steiner
Merlind Erika
ME
Becker
Matthias
M
Kern
Jörg
J
Wiltfang
Ralph
R
Lucius
Stephan Thomas
ST
Becker
D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D003094:Collagen; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009917:Orbital Fractures / Q000503:physiopathology* / Q000601:surgery*; D019340:Osteotomy, Le Fort; D016687:Polydioxanone; D019651:Plastic Surgery Procedures / Q000379:methods*; D013314:Stress, Mechanical
D016687:Polydioxanone; D003094:Collagen