Cranial defect repair using e-PTFE: Part I. Evaluation of bone stiffness

Autologous bone grafts are the preferred material for craniofacial reconstr uction, but such procedures lead to increased operative time and bleeding, donor site morbidity, and graft resorption. The efficacy of expanded-polyte trafluoroethylene (e-PTFE) sheets to increase bone regeneration and remodel ing in cranial defects using a rabbit model was evaluated by mechanical tes ting, New Zealand white rabbits were divided into 3 groups and sacrificed 6 months after surgery. In the Split Table group, (n = 16), a bilateral bone defect was created on the outer table of the parietal bones. In the Full T able group, (n = 16), a bilateral defect was created through both the inner and outer table of the cranium, The control group, (n = 10) was subjected to a sham operation. Indentation testing was performed to determine the sti ffness of newly formed bone in and around the defect, Near the center of th e defect, Split Table defects repaired with e-PTFE resulted in significantl y stiffer bone than regenerated control bone. The Full Table defects repair ed with e-PTFE also resulted in hone significantly stiffer than control reg enerated bone around the central region of the defect. The data supports th e hypothesis that e-PTFE improves the repair of cranial defects in a rabbit model, It is surmised that the porosity of the e-PTFE provides a stable sc affold for migration of tissue regenerating cells, which may be preferentia lly localized near the cranial suture lines. This porosity may also provide a harrier to fibrous tissue regenerating cells. (C) 2000 John Wiley & Sons , Inc.