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Mian, S.H.; Moiduddin, K.; Elseufy, S.M.; Alkhalefah, H. Adaptive Mechanism for Designing a Personalized Cranial Implant and Its 3D Printing Using PEEK. Polymers 2022, 14, 1266. [ Google Scholar] [ CrossRef] Gilardino MS, Karunanayake M, Al-Humsi T, Izadpanah A, Al-Ajmi H, Marcoux J, et al. A comparison and cost analysis of cranioplasty techniques: autologous bone versus custom computer-generated implants. Journal of Craniofacial Surgery 2015; 1: 113–117.Jegadeesan, J.T.; Baldia, M.; Basu, B. Next-Generation Personalized Cranioplasty Treatment. Acta Biomater. 2022, 154, 63–82. [ Google Scholar] [ CrossRef] [ PubMed] Winkler, P.A.; Stummer, W.; Linke, R.; Krishnan, K.G.; Tatsch, K. The influence of cranioplasty on postural blood flow regulation, cerebrovascular reserve capacity, and cerebral glucose metabolism. Neurosurg. Focus 2000, 8, 1–9. [ Google Scholar] [ CrossRef] Among all alloplastic materials, titanium continues to be the mainstream material used in cranioplasty due to its excellent biocompatibility, resistance to infection, high strength to weight ratio, corrosion resistance, non-magnetic properties, and toughness ( Niinomi, 1998; Zhang and Chen, 2019). Titanium plates for cranial defect reconstructions were first described in 1974 ( Gordon and Blair, 1974). Since then, cranial reconstructions have witnessed tremendous progress in using computer-aided design (CAD) methods ( Cabraja et al., 2009; Wiggins et al., 2013; Bonda et al., 2015). Additive manufacturing (AM) or three-dimensional (3D) printing of titanium patient-specific implants (PSIs) made its way into cranioplasty, improving the clinical outcomes in complex surgical procedures ( Cho et al., 2015; Park et al., 2016; Moiduddin et al., 2019; Sharma et al., 2020). Furthermore, there has been a significant interest within the medical community in redesigning implants based on natural analogies ( Tejero et al., 2014; Brett et al., 2017).