[Complex reconstructions in the facial and cranial regions]

Comparison of Titanium and PEEK Medical Plastic Implant Materials for Their Bacterial Biofilm Formation Properties

This study investigated two of the most commonly used CAD–CAM materials for patient-specific reconstruction in craniomaxillofacial surgery. The aim of this study was to access the biofilm formation of Staphylococcus aureus, Streptococcus mutans, Enterococcus faecalis, and Escherichia coli on titanium and PEEK medical implant materials. Two titanium specimens (titanium grade 2 tooled with a Planmeca CAD–CAM milling device and titanium grade 5 tooled with a computer-aided design direct metal laser sintering device (CAD-DMLS)) and one PEEK specimen tooled with a Planmeca CAD–CAM milling device were studied. Bacterial adhesion on implants was evaluated in two groups (saliva-treated group and non-saliva-treated group) to imitate intraoral and extraoral surgical routes for implant placement. The PEEK medical implant material showed higher bacterial adhesion by S. aureus, S. mutans, and E. coli than titanium grade 2 and titanium grade 5, whereas E. faecalis showed higher adhesion to titanium as compared to PEEK. Saliva contamination of implants also effected bacterial attachment. Salivary coating enhanced biofilm formation by S. aureus, S. mutans, and E. faecalis. In conclusion, our findings imply that regardless of the implant material type or tooling techniques used, salivary coating plays a vital role in bacterial adhesion. In addition, the majority of the bacterial strains showed higher adhesion to PEEK than titanium.

[Current developments in primary and secondary surgical treatment of midface and periorbital trauma]

Fractures of the periorbita and the midface are among the most common bony facial injuries. Aesthetic and functional reconstruction is a challenge in clinical routine. This article illustrates recent developments in the primary and secondary surgical treatment of midface and periorbital trauma. Resorbable patches and films increase the anatomic reconstructive capacity and enable treatment of extensive orbital fractures. Orbital fractures with involvement of supporting key structures are advantageously reconstructed using patient-specific implants (PSI), which are fabricated by computer-assisted manufacturing techniques and positioned by intraoperative navigation. If late complications such as bulbar malposition and enophthalmos have occurred after the initial procedure, they can be addressed by overcorrective restoration of orbital volume. The use of PSI for initial fracture restoration of the midface is not yet established but may be useful in re-osteotomies of misconsolidated fragments. Extensive midface defects with significant soft tissue involvement can be reconstructed using microvascular grafts. Consecutive reconstructive procedures may include orthognathic surgery and local flap reconstruction. In summary, the integration and advancement of computer-assisted techniques now offers individualized reconstruction procedures, which may be a viable alternative to conventional implants and compression miniplates. Future developments may focus on the search for innovative biomaterials, which can be integrated into computer-aided design and manufacturing processes.

Outcome and Quality of Life after Individual Computer-AssistedReconstruction of the Midface

Often, midfacial defects are not only relevant regarding functional aspects but also esthetics of such congenital or acquired deformities impair significantly the patients' quality of life. Reconstructions of the midface do not only include replacing lost or non-developed tissue but moreover to achieve predictable results with regard to esthetics as well as function for the individual patient. Digital planning modalities including different surface and volume data in combination with modern additive manufacturing techniques for biomodel and implant production and intraoperative support by using real and virtual 3D volume data for navigation and intraoperative imaging, but also securing the outcome based on postoperative analysis have been implemented in modern midface reconstruction and represent new standards for medical care. The objective of this paper is to describe modern options of patient-specific midfacial reconstruction with integration of computer-assisted planning and production techniques.