Page 16 - Clinical relevance of current materials for cranial implants

14
Chapter 1
The reconstruction of calvarial defects is called a cranioplasty. In some cases the autologous bone may not be available because of multiple fractures, infection, resorption, depletion, or even discontinuation of an institutional bone bank due to increasing storage costs and (inter)national regulations12,13. Therefore, artificial, alloplastic materials, for example titanium, poly (methyl methacrylate) (PMMA), hydroxyapatite (HA), and poly(ether ether ketone) (PEEK) are alternative materials to cover the remaining cranial defects13,14 (Figure 1C). The aim of the cranioplasty is to protect the brain, achieve a good cosmetic outcome, decrease neurologic problems and increase social performance12.
It has been estimated that cranioplasties are performed at a rate of 25 patients per 1 million people. This – relatively- straightforward procedure remains challenging for surgeons because of the anatomy, aesthetics and functional contouring of the skull. A large number of short- and long-term complications after cranioplasties have been reported, including infection, hematoma and resorption. These complications results in medical, social and economic disadvantages and illustrate that there is no ideal reconstruction method or reconstruction material yet for cranioplasty.
The ideal material for cranioplasties should have specific requirements: good biocompatibility, easy to use, a satisfactory esthetic outcome, inexpensive, mechanical properties similar to human bone, ability to be sterilized, a low-infection rate, and the capacity to integrate with the surrounding bone.