Page 214 - Clinical relevance of current materials for cranial implants
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Chapter 11
Chapter 7 presents a patient with a squamous cell carcinoma with bony invasion into the scalp, a rarely described phenomenon in the literature. The craniectomy was performed using a resection template and a control mold. For the reconstruction, a cranioplasty of PEEK was inserted, including a latissimus dorsi flap with a split- thickness skin graft. Clinically and aesthetically, the reconstruction was satisfactory. However, the reconstruction was complicated by a wound dehiscence, which was stable after one year
Part V: Towards the ideal material
For the development of new materials for cranioplasty, the material properties are crucial. These must be stable, safe and strong. In chapters 8 and 9, in vitro studies were performed with different types of PMMA.
In chapter 8, the amount of released, non-polymerized, monomers (residual monomers) was analyzed in four different PMMA-based materials with different compositions and fabrication methods (Vertex Self-Curing, Palacos R+G, DePuy CMW- 3 and NextDent C&B MFH). The specimens were inserted in bottles filled with distilled water at 37.0° C. After several time intervals – ranging between 1 hour and 14 days - a sample was taken from the water. With the aid of high-pressure liquid chromatography (HPLC), the percentage of released residual monomers was determined. Different patterns of released residual monomers were found. NextDent C&B MFH showed the lowest percentage of released residual monomers (23.9 μg/g). After the first hour, this material showed the highest amount of released residual monomers. However, after one hour no more release of residual monomers was detected from this material. Hence, this composite of PMMA could be a good option for a new material for cranioplasties.
In chapter 9, three different types of PMMA-based materials (Vertex Self-Curing, Palacos R+G and NextDent C&B MFH) were sterilized with four different methods (ethylene oxide, hydrogen peroxide plasma gas, autoclavation, and gamma- irradiation).
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