Patient-Specific Augmentation Rhinoplasty Using a Three-Dimensional Simulation Program and Three-Dimensional Printing.Background
 The convergence of three-dimensional (3D) simulation, tissue engineering, and 3D printing technology is creating a paradigm shift in plastic surgery.  In augmentation rhinoplasty, determining the ideal material and design method has been a critical issue for many years.  Thus, these technologies are expected to make important contributions to augmentation rhinoplasty.


 Objectives
 We sought to validate the feasibility of the 3D carving simulation and patient-specific implant fabrication system (3D carving system) in a clinical trial using reproducibility tests.


 Patient-specific implants were designed using a program developed in-house with preoperative computed tomography (CT).  Negative molds of the implant were fabricated by a 3D printer and silicone was injected into these molds.  Ten actual silicone implants were fabricated and compared with virtually designed implants.  Seven patients underwent surgery and postoperative CT to confirm implant positioning.


 Virtually designed implants were produced into actual implants within 0.07 mm with a 0.17% ± 0.11% difference.  The percentage within the gap was the highest at the cephalic end of the implant and reduced from the cephalic to caudal end (most cephalic point: 100%; rightmost and leftmost point of the implant at the caudal end of the nasal bone: 57.1% and 71.4%, respectively; rightmost and leftmost point at the supratip break: 28.6% and 28.6%, respectively; and most caudal point: 0%).


 Conclusions
 The 3D carving system can facilitate rhinoplasty by enabling the more intuitive, rapid, and accurate fabrication of implants irrespective of surgeon experience level.


 Level of Evidence

C