Barile Claudia, Cianci Claudia, Paramsamy Kannan Vimalathithan, Pappalettera Giovanni, Pappalettere Carmine, Casavola Caterina, Laurenziello Michele, Ciavarella Domenico
Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, Bari, Italy.
Dipartimento di Medicina Sperimentale e Clinica, Università di Foggia, Foggia, Italy.
PLoS One. 2025 Feb 5;20(2):e0318207. doi: 10.1371/journal.pone.0318207. eCollection 2025.
The widespread adoption of clear aligners in orthodontic treatments in recent years has necessitated a more precise examination of the mechanical properties of the devices currently available in orthodontics. Recent studies indicate that aligners, when exposed to the forces exerted during swallowing, undergo fatigue-like phenomena, leading to chip formation and cracks. The cumulative damage results in a compromised fit between the tooth and aligner, which is crucial for the effective execution of orthodontic treatment. Additionally, the formation of chips poses a potential risk to patients, as there is a possibility of inadvertently ingesting microplastics that become detached from the aligner over time. This study attempts to assess the release of microplastics from the aligners subjected to cyclic compressive loading. Three different aligners (Essix Ace, Ghost Aligner and Invisalign) are tested to simulate swallowing conditions over the aligner usage period. The mechanical performance is studied in terms of the energy absorbed by the aligner, which shows that the Essix Ace has a stable energy absorption behaviour, while the energy absorbed by the Invisalign is significantly higher than their counterparts. Ghost Aligner did not perform well in the cyclic compression tests. The microplastics (MPs) released by the aligners are examined under an optical microscope. A dimensional analysis based on k-means image segmentation and edge detection algorithm is developed to analyse the MPs. The dimensional analysis of the MPs revealed that the ingestion of the MPs released by all the three aligners does not pose a health risk.
近年来，透明矫治器在正畸治疗中的广泛应用使得有必要对正畸领域现有矫治器的力学性能进行更精确的研究。近期研究表明，矫治器在吞咽过程中受到外力作用时会出现类似疲劳的现象，导致碎片形成和裂纹。累积损伤会导致牙齿与矫治器之间的贴合度受损，而这对于正畸治疗的有效实施至关重要。此外，碎片的形成对患者构成潜在风险，因为随着时间推移，有可能会无意间摄入从矫治器上脱落的微塑料。本研究旨在评估经受循环压缩载荷的矫治器中微塑料的释放情况。测试了三种不同的矫治器（Essix Ace、Ghost Aligner和隐适美），以模拟矫治器使用期间的吞咽条件。从矫治器吸收的能量方面研究力学性能，结果表明Essix Ace具有稳定的能量吸收行为，而隐适美吸收的能量明显高于其他同类产品。Ghost Aligner在循环压缩测试中表现不佳。在光学显微镜下检查矫治器释放的微塑料。开发了一种基于k均值图像分割和边缘检测算法的尺寸分析方法来分析微塑料。微塑料的尺寸分析表明，所有三种矫治器释放的微塑料被摄入不会对健康构成风险。
