Osteoconductivity of porous polyethylene in human skull

Recently, biomaterials have been generally used in reconstruction of a bony defect or augmentation of the facial skeleton. Medpor implants in vivo in animal models showed both soft tissue and bony ingrowth into its pores and have been widely accepted to have an osteoconduction activity. However, in an in vivo study in humans, there was no definite evidence of bony ingrowth into the pores of Medpor. This study examined the osteoconductivity of Medpor in human vivo.

We gained a total of 24 Medpor blocks when removing a distraction device in 11 patients with craniosynostosis. The Medpor blocks were used for secure placement of the distraction device. The blocks were taken out after distraction and consolidation periods. The surface of Medpor in contact with the bone was histologically examined to confirm the osteogenic activity.

There was no evidence of osteoconduction in all 24 specimens. The mean total duration of implantation was 2.5 months.

In human vivo, implantation of a porous polyethylene implant is thought to have no osteogenetic effect through osteoconductive activity even in young children.