ORTHODONTIC CLEAR ALIGNERS AS A POTENTIAL SOURCE OF MICROPLASTIC EXPOSURE: IMPLICATIONS FOR HUMAN HEALTH AND ENVIRONMENTAL SUSTAINABILITY

Alicja Stępień; Karol Szkarłat; Maksymilian Szklarski; Szymon  Targosz; Michał Stachel; Ewa Maraszewska; Weronika Szymacha; Aleksandra Płecka; Karol Zimnicki; Jędrzej Sztajura

doi:10.31435/ijitss.2(50).2026.5334

Authors

Alicja Stępień Voivodship Dental Clinic, Consulting Dental Prosthetics Department, Batorego 3, 31-135 Cracow, Poland https://orcid.org/0009-0003-2717-6030
Karol Szkarłat Medical University of Silesia in Katowice, Faculty of Medical Sciences in Katowice, Medyków 18, 40-752 Katowice, Poland https://orcid.org/0009-0004-2889-8382
Maksymilian Szklarski Medical University of Silesia in Katowice, Faculty of Medical Sciences in Katowice, Medyków 18, 40-752 Katowice, Poland https://orcid.org/0009-0001-6977-0666
Szymon Targosz Medical University of Silesia in Katowice, Faculty of Medical Sciences in Katowice, Medyków 18, 40-752 Katowice, Poland https://orcid.org/0009-0005-2251-5229
Michał Stachel Medical University of Silesia in Katowice, Faculty of Medical Sciences in Katowice, Medyków 18, 40-752 Katowice, Poland https://orcid.org/0009-0008-3264-4747
Ewa Maraszewska Medical University of Silesia in Katowice, Faculty of Medical Sciences in Katowice, Medyków 18, 40-752 Katowice, Poland https://orcid.org/0009-0003-0992-7144
Weronika Szymacha Medical University of Silesia in Katowice, Faculty of Medical Sciences in Katowice, Medyków 18, 40-752 Katowice, Poland https://orcid.org/0009-0000-1592-5602
Aleksandra Płecka Medical University of Silesia in Katowice, Faculty of Medical Sciences in Katowice, Medyków 18, 40-752 Katowice, Poland https://orcid.org/0009-0007-0075-5234
Karol Zimnicki Medical University of Silesia in Katowice, Faculty of Medical Sciences in Katowice, Medyków 18, 40-752 Katowice, Poland https://orcid.org/0009-0001-9687-2641
Jędrzej Sztajura Students’ Scientific Club, Department of Neurosurgery, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Medyków 18, 40-752 Katowice, Poland https://orcid.org/0009-0009-8975-731X

DOI:

https://doi.org/10.31435/ijitss.2(50).2026.5334

Keywords:

Clear Aligners; Microplastics; Orthodontic Materials; Polymer Degradation; Oral Health; Environmental Sustainability

Abstract

The widespread adoption of clear aligners has transformed contemporary orthodontic practice by providing an aesthetic and comfortable alternative to conventional fixed appliances. These appliances are primarily manufactured from thermoplastic polymers such as polyethylene terephthalate glycol (PETG), polyurethane, and polycarbonate. Although aligner therapy offers numerous clinical advantages, increasing attention has been directed toward the potential release of microplastics resulting from the mechanical and chemical degradation of these materials in the oral environment. Microplastics, defined as plastic particles smaller than 5 mm, have recently been detected in various human tissues and environmental systems, raising concerns regarding their potential biological and ecological impact.

This narrative review aims to summarize current scientific evidence regarding microplastic release from orthodontic clear aligners and to discuss its potential implications for human health and environmental sustainability. A literature search was conducted using the PubMed database to identify English-language publications published between 2020 and 2026. Studies addressing aligner materials, polymer degradation mechanisms, experimental evidence of microplastic release, and the biological or environmental effects of microplastic exposure were included.

Available studies indicate that orthodontic aligners may release micro- and nanoplastic particles due to mechanical wear, cyclic loading, and chemical interactions with saliva. Additionally, the increasing global use and disposal of thermoplastic aligners may contribute to environmental plastic pollution. Further interdisciplinary research is required to clarify the clinical significance of these findings and to support the development of safer and more sustainable orthodontic materials.

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