Resorbable synthetics (PDS foils) for bridging extensive orbital wall defects in an animal experiment comparison

: In a long term animal study (min 2 weeks; max 48 weeks) on 6 minipigs, clinical related defects of the medial orbital wall extending in the orbital roof (2.5 cm x 3.5 cm) were created. The defects were bridged by slowly resorbable polydioxanon implants (so called PDS-foils, Ethicon) of different thickness (0.25/0.50 mm) and compared to control defects of identical size. The histological findings reveal: 1. After 29 weeks the resorption of both PDS-implants had been completely finished. Only the morphological intact implants had osteoconductive capabilities. 2. The osseous regeneration of the orbital defects started from the osteotomized margins of the orbital wall. The regenerates were covered by unaffected mucosa. 3. The bony regeneration was supported by the activated periosteal membrane. 4. The resorbed PDS-implants were being replaced by a tight scar tissue, which did not had any adjection to the orbital content. 5. The control defects showed a prolapse of the soft tissue with resulting enophthalmos. 6. According to the material specific characteristics, PDS-foils allow a sufficient bridging of even great and anatomically demanding orbital defects. 7. Notice: The hydrolytical broken down implant material may produce an irritation of the surrounding tissue causing a foreign body granuloma.