All patients underwent cone-beam-computed tomography (CBCT) (3D Accuitomo F17, MORITA, Kyoto, Japan) preoperatively, including the mandibular condyle and maxilla. The first step consisted of obtaining Digital Imaging and Communications in Medicine (DICOM) files from CT data. The 2D CT images were reconstructed into 3D CT images using the Volume Extractor® software (Volume Extractor 3.0, i-Plants Systems, Iwate, Japan) [32 (link),33 (link)] (Figure 1 A). Using this software, images were processed to remove artifacts and unwanted structures. After this process, the software was transformed into a digital 3D object file (Standard Tesselation Language, or STL). The STL file was imported into Geomagic Freeform Software (3D Systems, Rock Hill, SC, USA), where it became “digital clay”. A Geomagic Touch haptic device (3D Systems) was used to modify the peripheral artifacts and subtract several unwanted objects. With this preparation, a computer simulation was performed by virtual reconstructive surgeons (K.O., I.H., and S.K.) (Figure 1 B). Additionally, virtual simulations of occlusal rehabilitation were performed to establish occlusion on the computer. After virtual bone augmentation, dental implant placement simulation or virtual conventional prosthetic treatments were continued with consideration of the opposing dentition. In some cases, after the computer simulation, these data were used to confirm the occlusal relationship on a 3D-printed model or a conventional individual dental cast model. The cases included a variety of prosthetic conditions with conventional dentures, dental implant prostheses or no prostheses. In some cases, the patient’s requirements changed as the mandibular and alveolar reconstruction progressed with increasing patient motivation for occlusal reconstruction. As the present research aimed to evaluate the PCBM graft with TiMesh using virtual reconstruction surgery, the following research will clarify the establishment of occlusal reconstruction. Implant installation simulations may also be performed if dental implant treatment is a prerequisite. Digital data were imported into the implant planning software (CoDiagnostiX, Straumann, Basel, Switzerland) by prosthodontists (H.K., N.S.) (Figure 1 C).
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