In-House 3D Printed Positioning and Cutting Guide System for Mandibular Reconstruction. Protocol and case report.

Maxillofacial surgery planning has been improved by technological advances in 3D printing. The use of customized cutting and positioning guides allows intraoperative reproduction of pre-planned osteotomy cuts, resulting in increased surgical accuracy, reduced surgical time and improved esthetic and functional outcomes. Our paper presents a new method for creating and printing in-house cutting and positioning guides. A computer program (Brainlab iPlan) was used to segment the mandible for three-dimensional planning from imported conventional computed tomography (CT) scans. The virtual model of the mandible was printed on a stereolithography (SLA) 3D printer and a reconstruction plate was adapted to the printed model. The surface of the model and the screw-retained plate was scanned using a structured light surface 3D scanner (Artec Eva). The obtained scan of the jaw and plate in position was processed and transformed into an STL file. Free software (Autodesk Meshmixer) superimposes the initial jaw on the scanned jaw with the plate, designing a customized hybrid cutting guide that allows accurate intraoperative positioning, knowing the exact position of the reconstruction plate screws in the jaw. The total design, fabrication and 3D printing time for the in-house hybrid guide was 595 min. The average total printing cost was EUR 16. We found the technique to be simple and repeatable. We present and describe here a novel and simple technique for in-house 3D printed positioning and cutting guide system which can be applied to overall maxillofacial area. In cases of mandibular reconstruction, this protocol guarantees an adequate esthetic and functional result. Oral cancer, 3D surgery, CAD/CAM, personalized medicine, surgical guides, in house.