AccScience Publishing / MSAM / Volume 5 / Issue 1 / DOI: 10.36922/MSAM025260054
ORIGINAL RESEARCH ARTICLE

Personalized antimicrobial and soundproof earplugs through embedded-suspension 3D printing of polydimethylsiloxane-Ag composites for the prevention of swimmers’ otitis externa

 

Lili Qin1* Xinran Qian1 Dengyun Xu1 Jianming Yang2 Junye Ren1 Jialu Lu2 Wenjia Zhang1 Tianfeng Lu1 Wenrui Wang3* Ai Du2*
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1 Sports and Health Research Center, Department of Physical Education, Tongji University, Shanghai, China
2 Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai, China
3 Anhui Provincial Key Laboratory of Tumor Evolution and Intelligent Diagnosis and Treatment, School of Life Sciences, Anhui Engineering Research Center for Neural Regeneration Technology and Medical New Materials, Bengbu Medical University, Bengbu, Anhui, China
MSAM 2026, 5(1), 025260054 https://doi.org/10.36922/MSAM025260054
Received: 27 June 2025 | Accepted: 25 July 2025 | Published online: 6 October 2025
© 2025 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )
Abstract

Aquatic activities, particularly swimming, have been demonstrated to enhance physical conditioning and psychological well-being. However, the risk of water-induced otitis externa—caused by microbial colonization in the external auditory canal—often deters sustained participation in aquatic sports. Traditional swimming earplugs are typically limited in terms of comfort, water resistance, and antimicrobial protection, which can lead to potential ear canal infections and reduced effectiveness in preventing water ingress. In this study, we proposed using 3D scanning and printing technology to produce personally customized swimming earplugs to address these challenges. Embedded-suspension 3D printing technology was applied to fabricate structures using non-self-supporting Polydimethylsiloxane (PDMS) ink, printing hydrophobic ink in a hydrophilic system. The 3D-printed PDMS/Ag-3% composites exhibited an excellent inhibition rate (99.89%), good sound insulation performance (>30 dB, 1000–6300 Hz, 8 mm thickness), elasticity (elongation at break of 62.93%), and low modulus (0.85 MPa). We then recruited 60 beginner swimmers for a wear trial to demonstrate the effectiveness of personalized earplugs in preventing otitis externa and reducing ear canal irritation. This approach not only highlights the potential of 3D printing technology in sports equipment but also offers new insights for developing customized wearables.

Graphical abstract
Keywords
3D printing
Swimming earplugs
Swimmer’s ear prevention
Sports equipment
Sports injury prevention
Funding
This work was supported in part by the Open Project of Anhui Engineering Research Center for Neural Regeneration Technology and Medical New Materials (AHNR2024Z002).
Conflict of interest
The authors declare that they have no competing interests.
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Materials Science in Additive Manufacturing, Electronic ISSN: 2810-9635 Published by AccScience Publishing