Modern Applications of 3D Printing: The Case of an Artificial Ear Splint Model

Three-dimensional (3D) printing is a leading manufacturing technique in the medical field. The constantly improving quality of 3D printers has revolutionized the approach to new challenges in medicine for a wide range of applications including otoplasty, medical devices, and tissue engineering. The aim of this study is to provide a comprehensive overview of an artificial ear splint model applied to the human auricle for the treatment of stick-out protruding ears. The deformity of stick-out protruding ears remains a significant challenge, where the complex and distinctive shape preservation are key factors. To address this challenge, we have developed a protocol that involves photogrammetry techniques, reverse engineering technologies, a smart prototype design, and 3D printing processes. Specifically, we fabricated a 3D printed ear splint model via fused deposition modelling (FDM) technology by testing two materials, a thermoplastic polyester elastomer material (Z-Flex) and polycaprolactone (PCL 100). Our strategy affords a custom-made and patient-specific artificial ear aligner with mechanical properties that ensures sufficient preservation of the auricular shape by applying a force on the helix and antihelix and enables the ears to pin back to the head.

Development of a High-Fidelity, 3D Printed Otoplasty Surgical Simulator

Background and Hypothesis: Protruding ears, also known as prominauris, are prevalent worldwide at an occurrence rate of about 5%. Children with prominauris report lower self-esteem and experience increased teasing and social isolation at school. From a functional standpoint, protruding ears can make wearing prescription glasses difficult. This increased stress and anxiety and impaired functionality lead children and families to seek treatment. One of the most effective treatments for protruding ears is otoplasty. This procedure involves an incision in the back of the ear and the placement of non-resorbable sutures to reform the ear. Alternatively, the procedure can be performed using an incisionless technique. As this is an elective procedure done commonly in children, adequate education of medical trainees is critical to ensure the proper level of skill is attained and patient satisfaction is maximized. Currently, teaching otoplasty is done with cadavers and supervised procedures with an attending. Surgical simulators are employed in the instruction of a variety of surgical procedures and allow residents to practice in a zero-risk environment. In addition, 3D printing has facilitated the development of surgical simulators allowing for a more cost-effective, consistent, and anatomically correct simulator. We developed an ear model made from silicone for trainees to practice traditional and incisionless otoplasty. Project Methods: The otoplasty surgical simulator was developed by isolating an ear from a computed-tomography scan in the Materialise software to create a 3D model. This model was then altered to create a negative mold. The mold was printed using fusion deposition printing with 1.75 MM polylactic acid filament. After printing, the mold was filled with Dragon Skin Silicone Shore 20 to simulate ear cartilage. The model was then coated in a layer of Dragon Skin Silicone Shore 10 to simulate a layer of skin. Conclusion and Potential Impact: This otoplasty simulator will next be validated by expert surgeons and then used in a surgical simulation workshop for surgical trainees. Because of the low-cost of the surgical simulator and the ease of manufacturing, this simulator can also be used to train surgeons abroad where access to surgical training may not be readily available.

Otoplasty and Auricular Reconstruction

Due to the variety of abnormalities, surgery of the auricle is one of the most complex challenges in facial plastic surgery. They reach from mild protruding ears or isolated abnormalities of the supporting structures, mainly the helical rim and antihelix, over cup ear deformities and miniears all the way to severe microtia and anotia. In this article, the authors present a short overview of auricular abnormalities and malformations and their treatment options based on their experiences gained over three decades of special service for patients with auricular malformations.

Otoplasty for Protruding Ears, Cryptotia, or Stahl’s Ear

If the neonate with protruding ears, mildly constricted ears, a Stahl’s ear, or even cryptotia is seen by the plastic surgeon during the child’s first days of life, the timing is auspicious. By initiating immediate steps to mold the ear with tapes and splints, complete correction of the problem without surgery is a realistic expectation. The urgency and the effectiveness of early nonsurgical treatment of such ears is not yet widely appreciated by those responsible for primary medical care of neonates. It is the plastic surgeon’s task to heighten awareness of such treatment.

The Protruding Ear: Cosmetic and Reconstruction

Ear prominence is a relatively common cosmetic deformity with no associated functional deficits, but with profound psychosocial impact, especially in young patients. Protruding ears in children have propagated surgical advances that incorporate reconstructive techniques. Here we outline a systematic framework to evaluate the protruding ear and present various reconstructive surgical options for correction. Both cosmetic and reconstructive perspectives should be entertained when addressing this anatomical deformity.