The effect of manufacturing techniques on custom-made titanium cranioplasty plates: A pilot study

This study investigated the effect of varying techniques on the surface characteristics of pressed titanium cranioplasty plates, commonly manufactured in laboratory practice. The aim was to highlight the variety of techniques currently used, assess these methods of manufacture and produce manufacturing recommendations.

A questionnaire identified manufacturing methods commonly used by maxillofacial prosthetists. The plate surfaces were examined using scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectrometry. The surface differences and titanium compositions were statistically analysed.

Bead blasting with aluminium oxide (Al₂O₃) showed a significant decrease (p < 0.001) in titanium surface composition, replaced by a large aluminium content. Trimming tool choice had a significant impact (p = 0.001) on surface contamination by smoothing wheel material deposition; however passivation and anodising techniques had no significant effect (p = 0.293 and p = 0.257, respectively) on the surface composition or roughness of titanium samples.

A large range of manufacturing techniques of titanium cranioplasty plates was confirmed and significant differences were found. Amongst other recommendations, bead blasting with Al₂O₃ is not recommended for commercially pure titanium implant surface finishing due to aluminium contamination. The recommendations outlined will minimise manufacturing time, reduce risk of complication (thus costs) and unify methods to enable a safe, reliable treatment.