Preliminary application of 3D printing technique in resection and reconstruction of mandibular ameloblastoma / 医疗卫生装备

Objective To investigate the primary application of 3D printing technique in vascularized fibula resection and grafting for mandible ameloblastoma. Methods The data of 3 cases of unilateral mandibular ameloblastoma were retrospectively collected.The thin slice CT scan of mandible was performed before operation.The scanned original data were imported into mimics 17.0 software for 3D reconstruction.Mirror image of the healthy side mandible was generated by the mirror image tool of the software.Preoperative planning,designing transplantation of vascularized fibula bone,pre-bending and pre-shaping titanium plate,surgical simulation were done by the mirror model.Results All operations were performed successfully,and were in agreement with the preoperative planning.The facial appearance and mandible function were both satisfactory.Conclusion 3D printing technology assisting mandibular ameloblastoma resection and bone graft reconstruction is able to optimize preoperative planning,provide individualized treatment and achieve postoperative satisfaction.

Biomechanical Comparison of an Intramedullary and Extramedullary Free-Tissue Graft Reconstruction of the Acromioclavicular Joint Complex

BACKGROUND: Several different surgical techniques have been described to address the coracoclavicular (CC) ligaments in acromioclavicular (AC) joint injuries. However, very few techniques focus on reconstructing the AC ligaments, despite its importance in providing stability. The purpose of our study was to compare the biomechanical properties of two free-tissue graft techniques that reconstruct both the AC and CC ligaments in cadaveric shoulders, one with an extramedullary AC reconstruction and the other with an intramedullary AC reconstruction. We hypothesized intramedullary AC reconstruction will provide greater anteroposterior translational stability and improved load to failure characteristics than an extramedullary technique. METHODS: Six matched cadaveric shoulders underwent translational testing at 10 N and 15 N in the anteroposterior and superoinferior directions, under AC joint compression loads of 10 N, 20 N, and 30 N. After the AC and CC ligaments were transected, one of the specimens was randomly assigned the intramedullary free-tissue graft reconstruction while its matched pair received the extramedullary graft reconstruction. Both reconstructed specimens then underwent repeat translational testing, followed by load to failure testing, via superior clavicle distraction, at a rate of 50 mm/min. RESULTS: Intramedullary reconstruction provided significantly greater translational stability in the anteroposterior direction than the extramedullary technique for four of six loading conditions (p < 0.05). There were no significant differences in translational stability in the superoinferior direction for any loading condition. The intramedullary reconstructed specimens demonstrated improved load to failure characteristics with the intramedullary reconstruction having a lower deformation at yield and a higher ultimate load than the extramedullary reconstruction (p < 0.05). CONCLUSIONS: Intramedullary reconstruction of the AC joint provides greater stability in the anteroposterior direction and improved load to failure characteristics than an extramedullary technique. Reconstruction of the injured AC joint with an intramedullary free tissue graft may provide greater strength and stability than other currently used techniques, allowing patients to have improved clinical outcomes.