3D imaging in dentistry plays an essential part in diagnostics and treatment planning. To transform digital images into a real object that can be experienced haptically may provide new opportunities to practitioners regarding patient communication, skills training, and treatment planning. Therefore, the aim of this article is to provide a practical guide from 3D imaging to 3D printing using low-cost printers and open source software; the authors used 3D Slicer software and a Meshmixer printer, including the printer's own software. The article presents step-by-step instructions on how to perform rapid prototyping via fused deposition modeling (FDM) and stereolithography (SLA). As an example, we printed the skull of a patient with Saethre-Chotzen syndrome who was undergoing maxillofacial surgery. The protocol explained here should enable the technically interested clinician to produce patient-specific 3D models in-house, prefabricate osteosynthesis plates, and take advantage of the benefits of 3D printing for dentist-patient communication. Keywords: 3D imaging, 3D printing, FDM printing, SLA printing, rapid prototyping, preoperative treatment planning