Three-dimensional (3D) printing has been used in medical education to create models and simulation opportunities. Audiology students could practice hearing aid fitting skills on an ear simulator. The purpose of this project is to pilot the process of using 3D printing to create an ear simulator. Photogrammetry was used to scan an ear impression. Resultant files were converted to STL for 3D printing. FDM and SLA 3D printers created final models, which were compared for print time, quality, and materials.

ABSTRACT

INTRODUCTION• 3D printing is an innovative technology used in health

professions education1.• Audiology students must master hearing aid fitting skills,

such as making ear impressions and conducting probe-microphone measures2.

• Use of an ear simulator allows students to practice skills on a realistic model – without potential harm to patients3.

• An ear/head simulator is available4, but may not be affordable to some. The purpose of this project is to pilot the process of using 3D printing to create an ear simulator.

METHODS

Five steps are needed to create a 3D printed object5. Methods are shown in figure 1 below.

Pilot Project: Feasibility of Using 3D Printing to Create an Ear SimulatorJ James, BS1, K Boyce, PhD2, K Wyatt3, B Reed3, M Hudson, PhD, F-AAA1

Department of Communication Sciences & Disorders1, Department of Medical Imaging & Radiation Sciences2

University of Oklahoma Health Sciences Center, Oklahoma City, OKBizzell Memorial Library, University of Oklahoma, Norman, OK3

RESULTS

CONCLUSIONS

IMPLICATIONS TO ALLIED HEALTH

Capture the area of interest

• We used an ear impression for the ear canal and concha.

Create a 3D rendering with an image set of an object & convert it to an OBJ file

• Photogrammetry converted the rendering to an OBJ file. An online pinna dataset was used to complete this step.

Transform the 3D object to a standard triangle language (STL) file to be printed.

• Requires expertise in computer aided design (CAD) software to prepare STL files for printing

Choose a printer

• We used two different printers

• a stereolithography (SLA) 3D printer in OKC, OK (figure 2)

• a fused deposition modeling (FDM) 3D printer in Norman, OK (figure 3)

Choose materials

• We used three materials

• durable resin with the SLA printer

• tough material with the SLA printer

• thermoplastic polyurethane (TPU) with the FDM printer

Figure 2 SLA printer using durable resin and tough (blue) materials.

Figure 3 FDM printer using thermoplastic polyurethane material.

• We used three materials: 1) durable resin, 2) tough (blue) material, and 3) thermoplastic polyurethane (TPU).

• Print quality was the best for the TPU material. However, TPU was judged to be more rigid than we expected.

• Print time for each material is shown in figure 4 below. Print time is shortest for the TPU (best quality) material.

• Figures 5-7 show printed objects. Figure 8 shows the ear simulator with the TPU ear.

• It is feasible to create an ear simulator using 3D printing.• Printing was completed over night, and print time was

acceptable. The overall process was time intensive. The cost for materials was reasonably low.

• Print quality was judged to be acceptable for the TPU material, but not the tough material or durable resin.

Figure 5 Durable Resin Figure 6 Tough Material

Figure 8 Simulator with TPU MaterialFigure 7 TPU Material

7

7

6.5

0 1 2 3 4 5 6 7 8

DURABLE RESIN

TOUGH (BLUE)

TPU

Print Time (in hours)

Material Type

Print Time for Three Materials

AKNOWLEDGMENTS

MIRS 3D Printing LabDept of Medical Imaging & Radiation SciencesCollege of Allied Health1200 Stonewall AvenueOUHSC, OKC, OK 73117https://alliedhealth.ouhsc.edu/Centers-Labs/MIRS-3D-Printing-Lab

• Interprofessional teaming with the MIRS 3D Printing Lab, Emerging Technologies Lab, and audiology was crucial to the success of this project.

• Expertise, materials, and equipment were provided by:

Emerging TechnologiesBizzell Memorial Library University of Oklahoma410 W. Brooks StreetNorman, OK 73019https://libraries.ou.edu/content/emerging-technologies