With the recent advances in three-dimensional (3D) imaging, computer-assisted surgical planning and simulation are now regularly used for analysis of craniofacial structures and improved prediction of surgical outcomes in orthognathic surgery. A variety of patient-specific surgical guides and devices have been designed and manufactured using 3D printing technology, which rapidly gained widespread popularity to improve the outcomes. The article presents an overview of 3D printing technology for state-of-the-art application in orthognathic surgery and discusses the impacts on treatment feasibility and patient outcome. The current available literature regarding the use of 3D printing methods in orthognathic surgery including 3D computer-aided design/computer-aided manufacturing, rapid prototyping, additive manufacturing, 3D printing, 3D printed models, surgical occlusal splints, custom-made guides, templates and fixation plates is reviewed. A Medline, PubMed, ProQuest and ScienceDirect search was performed to find relevant articles over the past 10 years. A total of 318 articles were found, out of which 69 were publications addressing the topic of this study. An additional 9 hand-searched articles were added. From the review, we can conclude that the use of 3D printing methods in orthognathic surgery provide the benefit of optimal functional and aesthetic results, patient satisfaction, and precise translation of the treatment plan.

BackgroundAlthough conventional two-dimensional (2D) methods for orthognathic surgery planning are still popular, the use of three-dimensional (3D) simulation is steadily increasing. In facial asymmetry cases such as in cleft lip/palate patients, the additional information can dramatically improve planning accuracy and outcome. The purpose of this study is to investigate which parameters are changed most frequently in transferring a traditional 2D plan to 3D simulation, and what planning parameters can be better adjusted by this method.Patients and MethodsThis prospective study enrolled 30 consecutive patients with cleft lip and/or cleft palate (mean age 18.6±2.9 years, range 15 to 32 years). All patients received two-jaw single-splint orthognathic surgery. 2D orthodontic surgery plans were transferred into a 3D setting. Severe bony collisions in the ramus area after 2D plan transfer were noted. The position of the maxillo-mandibular complex was evaluated and eventually adjusted. Position changes of roll, midline, pitch, yaw, genioplasty and their frequency within the patient group were recorded as an alternation of the initial 2D plan. Patients were divided in groups of no change from the original 2D plan and changes in one, two, three and four of the aforementioned parameters as well as subgroups of unilateral, bilateral cleft lip/palate and isolated cleft palate cases. Postoperative OQLQ scores were obtained for 20 patients who finished orthodontic treatment.Results83.3% of 2D plans were modified, mostly concerning yaw (63.3%) and midline (36.7%) adjustments. Yaw adjustments had the highest mean values in total and in all subgroups. Severe bony collisions as a result of 2D planning were seen in 46.7% of patients. Possible asymmetry was regularly foreseen and corrected in the 3D simulation.ConclusionBased on our findings, 3D simulation renders important information for accurate planning in complex cleft lip/palate cases involving facial asymmetry that is regularly missed in conventional 2D planning.

Therapeutic, IV.