Preoperative virtual surgical planning and the use of 3D-printed patient-specific models and cutting guides are increasingly being used in the reconstruction of mandibular defects with a free bone flap. This technology offers several advantages over conventional surgery, such as reduced operating time, reduced bone flap ischaemia time, and the ability to perform more complex and precise reconstructions. This review presents the evidence supporting 3D-assisted surgery for mandibular defect reconstruction and discusses the utilisation of commercial vendors versus in-house 3D-printing solutions.