Clinical Application of Three-Dimensional-Printed Magnetic Connection Digital Guides for Precise Segmental Maxillary Osteotomy

This study introduces the design and clinical application of a novel magnetic-connection digital osteotomy guide to enhance the precision and efficiency of segmental maxillary osteotomy. Segmental Le Fort I osteotomy is an essential technique for correcting complex transverse and vertical dental-maxillofacial deformities, yet traditional methods involving manual plaster model surgery are prone to significant errors. To address these challenges, this protocol integrates virtual surgical planning (VSP) using CT scans and specialized modeling software to create a patient-specific, 3D-printed two-part guide system. The primary component is designed to guide the horizontal Le Fort I osteotomy and bilateral premolar extraction lines. Once the maxilla is down-fractured, a secondary segmental guide is connected to the primary component via four embedded neodymium magnets, each measuring 3 mm in diameter and 1.5 mm in thickness. This magnetic connection provides a stable, rapid, and interference-free attachment that allows for precise guidance of palatal and midline osteotomy lines. This protocol demonstrates the clinical application of a modular magnetic guide system for transferring the virtual osteotomy plan in patients with maxillary protrusion and arch width discrepancies. Postoperative color-map analysis showed local surface deviations of approximately 0.5-0.9 mm around the visible osteotomy margins, supporting the preliminary accuracy of osteotomy-region transfer. The modular magnetic design provides staged osteotomy guidance and may reduce the need for repeated adjustments, unnecessary bone removal, and soft-tissue manipulation, which is consistent with vascular-preserving principles, although segment perfusion was not directly assessed. Neodymium magnets are biocompatible, maintain stability after sterilization, and are cost-effective due to their reusability. Despite the potential fragility of current three-dimensional (3D)-printed resin materials, the magnetic connection digital osteotomy guide offers significant clinical value by bridging the gap between virtual planning and surgical execution. This method ensures highly accurate bone removal and positioning, representing a promising advancement for complex orthognathic surgical procedures.