Taking Simulation to the Next Level: 3D Printing 101

Ann W. Plum, MD, on behalf of the Simulation Education Committee

How Does 3D Printing for Simulation Work?

The process begins with the design. Most often, the design is based on a CT scan or MRI, but it does not have to be. ^{1, 2} The design is created and processed in a computer-aided design program. ^{1, 2} This software is what specifically allows the design to be rendered as a 3D structure. After the 3D structure is completed, it must be broken down into individual 2D slices that can be printed.^{1, 2} The operator must decide on the parameters for each slice, most notably the thickness of the slice. ^{1, 2} The thickness of each slice directly impacts the level of detail of the ultimate product.¹ After the parameters are chosen, the 3D image is broken down into multiple 2D images using a slicing software program.^{1, 2} The coded sequence of 2D images is then transferred to the 3D printer. ^{1, 2} Each 2D image is printed and stacked upon the prior one based on the coded sequence of 2D images, creating the 3D structure. ^{1, 2}  Once the 3D structure is created, the postprocessing step occurs, where the structure is fine-tuned as needed. ^{1, 2} The postprocessing can vary quite a bit depending on whether the 3D-printed object is being used as a mold for the creation of the final model or as the model itself. ^1-3

What Do I Need to Start 3D Printing?

• An idea
• Computer-aided design program
• An image-slicing program
• A substance used for printing (such as polylactic acid filament)^{1, 4-6}
• A 3D printer

What Are the Benefits of Incorporating 3D Printing in Simulation?

Ultimately, the goal of simulation is to provide education on certain tasks or skills in a safe space where the learners can learn and make mistakes without imposing risks as they gain skills and knowledge that will increase their competence. 3D printing has been used to create models that learners can perform numerous different tasks on that mimic real patient anatomy. These models have only increased in realistic appearance and tactile feel, enhancing the experiences of each learner.

How Has 3D Printing Been Embraced in Simulation Within Otolaryngology?

3D printing has been utilized to simulate surgery in all facets of otolaryngology. It has been used in numerous otology simulation models to mimic the middle ear space as well as the entire temporal bone.^{1, 2, 4, 6-10} In facial plastics, 3D printing has been used in models to help teach microtia repair, cleft lip repair, palatoplasty, facial flaps, and fillers as well as in nasal models to practice septoplasties and rhinoplasties.^{1, 3, 5, 11- 14}   In pediatric otolaryngology and laryngology, 3D printing has been used to create models of normal larynges, as well as larynges that are affected with different pathologies (for instance subglottic stenosis, laryngeal cleft, laryngomalacia, and subglottic cysts) to help teach an array of open and endoscopic airway procedures.^{1, 11, 15-17} In rhinology and skull base surgery, 3D printing has been used to make models of the anterior skull base and sinonasal anatomy for simulations of skull base surgery and endoscopic sinus surgery.^{1, 18-20} In the head and neck, 3D printing has been used to create models for teaching parotidectomy and facial nerve dissections.²¹ These are only a few examples of applications within otolaryngology. In all of our subspecialties, 3D printed models have gained popularity as the capabilities to create models that not only accurately portray anatomic relationships but also mimic the tactile feedback between different types of tissues.^{1-3, 5}

Taking Simulation to the Next Level

Using 3D printing has provided an additional tool that is taking simulation in otolaryngology to the next level by enhancing the educational experience of both the learners and teachers. It allows us to embrace our creativity and innovative spirit. For those interested in learning more, I encourage you to apply to join the Simulation Education Committee and attend the Simulation Showcase and Sim Tank at the next AAO-HNSF Annual Meeting & OTO EXPO.

References

1. VanKoevering KK, Malloy KM. Emerging Role of Three-Dimensional Printing in Simulation in Otolaryngology. Otolaryngol Clin North Am. 2017;50(5):947-958.
2. Ang AJY, Chee SP, Tang JZE, et al. Developing a production workflow for 3D-printed temporal bone surgical simulators. 3D Print Med. 2024;10(1):16.
3. Berens AM, Newman S, Bhrany AD, Murakami C, Sie KC, Zopf DA. Computer-Aided Design and 3D Printing to Produce a Costal Cartilage Model for Simulation of Auricular Reconstruction. Otolaryngol Head Neck Surg. 2016;155(2):356-359. 
4. Gadaleta DJ, Huang D, Rankin N, et al. 3D printed temporal bone as a tool for otologic surgery simulation. Am J Otolaryngol. 2020;41(3):102273.
5. Ho M, Goldfarb J, Moayer R, et al. Design and Printing of a Low-Cost 3D-Printed Nasal Osteotomy Training Model: Development and Feasibility Study. JMIR Med Educ. 2020;6(2):e19792.
6. McMillan A, Kocharyan A, Dekker SE, et al. Comparison of Materials Used for 3D-Printing Temporal Bone Models to Simulate Surgical Dissection. Ann Otol Rhinol Laryngol. 2020;129(12):1168-1173. 
7. Lähde S, Hirsi Y, Salmi M, Mäkitie A, Sinkkonen ST. Integration of 3D-printed middle ear models and middle ear prostheses in otosurgical training. BMC Med Educ. 2024;24(1):451.
8. Stramiello JA, Wong SJ, Good R, Tor A, Ryan J, Carvalho D. Validation of a three-dimensional printed pediatric middle ear model for endoscopic surgery training. Laryngoscope Investig Otolaryngol. 2022;7(6):2133-2138.
9. Jenks CM, Patel V, Bennett B, Dunham B, Devine CM. Development of a 3-Dimensional Middle Ear Model to Teach Anatomy and Endoscopic Ear Surgical Skills. OTO Open. 2021;5(4):2473974X211046598. 
10. Takahashi K, Morita Y, Ohshima S, et al. Creating an Optimal 3D Printed Model for Temporal Bone Dissection Training. Ann Otol Rhinol Laryngol. 2017;126(7):530-536. 
11. Chang B, Powell A, Ellsperman S, et al. Multicenter Advanced Pediatric Otolaryngology Fellowship Prep Surgical Simulation Course with 3D Printed High-Fidelity Models. Otolaryngol Head Neck Surg. 2020;162(5):658-665. 
12. Yang SF, Powell A, Srinivasan S, et al. Addressing the Pandemic Training Deficiency: Filling the Void with Simulation in Facial Reconstruction. Laryngoscope. 2021;131(8):E2444-E2448.
13. Tabaru A, Kapusuz Gencer Z, Öğreden Ş, Akyel S, Özum Ö, Bayram İ. Enhancing Facial Filler Training with 3D-Printed Models: A Prospective Observational Study on Medical Student Competence. Med Sci Monit. 2024;30:e945074. 
14. Reighard CL, Green K, Rooney DM, Zopf DA. Development of a Novel, Low-Cost, High-fidelity Cleft Lip Repair Surgical Simulator Using Computer-Aided Design and 3-Dimensional Printing. JAMA Facial Plast Surg. 2019;21(1):77-79. 
15. Falls M, Vincze J, Brown J, et al. Simulation of laryngotracheal reconstruction with 3D-printed models and porcine cadaveric models. Laryngoscope Investig Otolaryngol. 2022;7(5):1603-1610.
16. Kavanagh KR, Cote V, Tsui Y, Kudernatsch S, Peterson DR, Valdez TA. Pediatric laryngeal simulator using 3D printed models: A novel technique. Laryngoscope. 2017;127(4):E132-E137. 
17. Chandna M, Siddiqui S, Bertoni D, et al. Comparing cadaveric and 3D-printed laryngeal models in transcutaneous injection laryngoplasty. Laryngoscope Investig Otolaryngol. 2024;9(4):e1305. 
18. Low CM, Morris JM, Price DL, et al. Three-Dimensional Printing: Current Use in Rhinology and Endoscopic Skull Base Surgery. Am J Rhinol Allergy. 2019;33(6):770-781. 
19. Alrasheed AS, Nguyen LHP, Mongeau L, Funnell WRJ, Tewfik MA. Development and validation of a 3D-printed model of the ostiomeatal complex and frontal sinus for endoscopic sinus surgery training. Int Forum Allergy Rhinol. 2017;7(8):837-841. 
20. Chang DR, Lin RP, Bowe S, et al. Fabrication and validation of a low-cost, medium-fidelity silicone injection molded endoscopic sinus surgery simulation model. Laryngoscope. 2017;127(4):781-786. 
21. Reighard CL, Green K, Rooney DM, Zopf DA. Development of a Novel, Low-Cost, High-fidelity Cleft Lip Repair Surgical Simulator Using Computer-Aided Design and 3-Dimensional Printing. JAMA Facial Plast Surg. 2019;21(1):77-79.