An evaluation of the support provided by common internal orbital reconstruction materials.
OBJECTIVE
The objectives of this investigation were to assess the weight of the combined internal orbital contents, to evaluate the ability of common internal orbital reconstruction materials to resist loads, and to determine whether these materials provide enough load resistance to support the orbital contents.


METHODS
The combined exonerated internal orbital contents (globe, fat, extraocular musculature, neurovascular structures, lacrimal apparatus, and musculocutaneous lids) from 16 human orbits were weighed. Five each of 13 different internal orbital reconstruction materials (titanium mesh, bioresorbables, Marlex [CR Bard, Cranston, RI], Medpore [Porex Medical, College Park, GA], Silastic [Dow Coming, Midland, MI], dried calvarium) were evaluated for their ability to resist loads applied by Instron 85.11 mechanical testing device (Canton, MA) when used to reconstruct uniform orbital floor defects in synthetic skulls (Sawbones, Vashon Island, WA). Yield load, yield displacement, maximum load, and displacement at maximum load were measured. A comparison was then made between orbital content weight and the load-resisting capabilities of the various materials.


RESULTS
The weight of the combined internal orbital contents was 42.97+/-4.05 g (range, 37.80 to 51.03 g). All of the materials tested except Marlex mesh met or exceeded the requirements for support of the combined internal orbital contents.


CONCLUSIONS
Except in the instance of complete loss of the orbital floor, all of the materials tested should provide adequate orbital support.
D020341:Absorbable Implants; D000273:Adipose Tissue / Q000033:anatomy & histology; D001672:Biocompatible Materials / Q000737:chemistry*; D002102:Cadaver; D005069:Evaluation Studies as Topic; D005123:Eye / Q000033:anatomy & histology / Q000098:blood supply / Q000294:innervation; D005143:Eyelids / Q000033:anatomy & histology; D006801:Humans; D007765:Lacrimal Apparatus / Q000033:anatomy & histology; D008422:Materials Testing; D009801:Oculomotor Muscles / Q000033:anatomy & histology; D009915:Orbit / Q000098:blood supply / Q000294:innervation / Q000601:surgery*; D009929:Organ Size; D011095:Polyethylenes / Q000737:chemistry; D011126:Polypropylenes / Q000737:chemistry; D019736:Prostheses and Implants; D019651:Plastic Surgery Procedures / Q000295:instrumentation*; D012826:Silicone Elastomers / Q000737:chemistry; D013314:Stress, Mechanical; D013526:Surgical Mesh; D014025:Titanium / Q000737:chemistry; D016474:Weight-Bearing