Cranioplasty and Craniofacial Reconstruction: A Review of Implant Material, Manufacturing Method and Infection Risk

Background: Analysis of current literature highlights a wide variation in reported infection risk for different materials in cranial repair. The purpose of these composite materials are to mimic natural bone and assist in restoring function (structurally and aesthetically) to the human skull. This review aims to examine the meta-data in order to provide an amalgamated overview of potential trends between implant material, manufacturing method and infection risk, in order to provide a core reference point for future studies surrounding emerging biomedical materials in the fields of cranioplasty by providing base point for understanding the capabilities and limitations of current technologies. Methods: A search for articles was conducted, with the following criteria seen as fundamental in providing an accurate picture of the current landscape: publication in the last decade, provision of a numerical value for both number of implants and infection cases, patient sample of 10+, adult patients, and cranioplasty/cranial repair. Results: A total of 41 articles were seen to meet the author's inclusion criteria. Average infection rates per material ranged between 2.04% and 10.98%. The results indicate that there is variation between materials in regards to total infection risk, however, depending on the materials compared, this value may be insignificant. Alternative risk factors associated with infection, including surgical time, revisions and previous infection, have a greater impact on infection potential than material variation. Comparison of fabrication methods did highlight a notable effect on average infection rate. Trends can be observed showing that materials with greater levels of surface interaction and active support of tissue ingrowth presented greater infection resistance. Such characteristics are due to the physical structures of the implants. Conclusions: It can be said that the manufacturing methods can influence biomedical materials to assist in minimizing implant infection risk.