Page 135 - Clinical relevance of current materials for cranial implants

Resection templates with 3D virtual planning
A one-stage approach, with the use of saw templates, is used in other surgical, for instance in secondary orbitozygomatic complex reconstruction after trauma21,22,23,24,25. Fixation of the resection template is planned on the existing screw hole positions to ensure accurate resection and enable subsequent reconstruction. The saw template technique is also used to combine resection and reconstruction in head and neck oncologic resection with bony mandibular reconstruction with vascularized fibula grafts 24,5. Three surgical guides can be designed for different intra-operative steps in this comprehensive procedure: a resection template for the resection of the mandibular tumor, a resection template for the execution of the fibular osteotomy, and a reconstruction template for the final reconstruction22.
Evaluation of the accuracy of templates is describes in several studies21,25,26. Weijs et
al. calculated the difference in angulation of the screws and actual resection plane
compared to the planned resection in oromandibular reconstructions25. Mascha
et al. evaluated the accuracy of oromandibular reconstructions by measuring 6 distances between corresponding landmarks on the mandibular rami on the pre-
and postoperative CT-scans26. Here, the accuracy was calculated with the use of a continuous distance map of the PSI compared with its planned location.
Conclusion
One-stage craniectomy and reconstruction using a prefabricated resection template, control template, and PEEK PSI seems to be a viable and safe technique. Resection templates enable the use of a PSI for secondary cranial reconstruction in a one-stage surgical procedure. It can reduce operation time and number of surgical procedures, and may reduce cost. A major advantage for the patient is absence of a lidless and risky period, with an immediate aesthetically satisfying result.
Acknowledgment
Special thanks goes to R.D. Vreeken, 3D specialist in oral and maxillofacial surgery˛and Dr. A.R. Wittkampf, oral and maxillofacial surgeon, for sharing their experience in this field.
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