We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Cytotoxicity of Aligners – A Comprehensive Review
AI summary Read the abstract
This review examines the material composition and biocompatibility of orthodontic clear aligners made from polyurethane, PET-G, and polypropylene, finding that while the materials generally have low cytotoxicity, oral conditions cause microplastic and additive release that warrants long-term safety monitoring.
Orthodontic clear aligners have gained widespread popularity due to their esthetic appeal and functional advantages over traditional braces. This review explores the material composition, biocompatibility, and potential health implications associated with long-term intraoral use of clear aligners. Most aligners are fabricated from thermoplastic polymers such as polyurethane, polyethylene terephthalate glycol, and polypropylene, which generally exhibit low cytotoxicity. However, exposure to oral conditions–including saliva, temperature fluctuations, and mechanical stress–can lead to material degradation and the release of residual monomers or additives, potentially causing mild to moderate cytotoxic effects. The postpolymerization process significantly influences material stability and clinical performance, with advanced protocols improving polymerization efficiency and reducing toxic potential. In addition, mechanical wear of aligners can result in the release of microplastics into the oral cavity, raising concerns about their systemic and local biological effects. These microplastics may interact with gut microbiota, contribute to inflammation, and potentially translocate to systemic circulation. This review also highlights the importance of standardized testing methods, including MTT assays and microscopic analysis, for evaluating cytotoxicity and material integrity. To ensure patient safety, continued development of biocompatible materials and adherence to regulatory standards are essential. Clinicians should remain informed about material properties and recommend proper usage and maintenance to minimize potential risks associated with aligner therapy.
More Papers Like This
Biocompatibility and Safety of Orthodontic Clear Aligners and Thermoplastic Retainers: A Systematic In Vitro Review (2015–2025)
AI summary Read the abstract
This systematic review examined whether orthodontic clear aligners and retainers release harmful chemicals or microplastics in the mouth. While most products met safety standards, some materials did release detectable levels of bisphenol A and other chemicals, especially during initial wear and after aging, raising questions about long-term oral exposure.
Chemical leaching and microplastics from clear aligner materials: Current evidence and future perspectives
AI summary Read the abstract
This review found that orthodontic clear aligners can release microplastics and chemicals like BPA into the mouth during normal use. While most products meet current safety standards, the combination of mechanical wear, saliva, and temperature changes in the mouth accelerates material breakdown, making dental appliances an underrecognized source of daily microplastic exposure.
The Biosafety or Biocompability of Clear Aligner
AI summary Read the abstract
This review examined the biosafety of clear aligner orthodontic appliances, finding that prolonged intraoral wear can cause release of chemical leachates (including bisphenol A and residual monomers) and microplastic particulates, with potential biological effects that remain inconsistently characterized in the literature.
Release of Microplastics and Chemical Compounds from Clear Orthodontic Aligners: A Narrative Review of the Current Evidence
AI summary Read the abstract
This review summarizes existing research on clear plastic orthodontic aligners, worn in the mouth, and whether they release chemicals and tiny plastic particles as they wear down. Lab studies found that aligner surfaces can develop roughness and tiny cracks, sometimes releasing chemicals and microplastics, but most evidence comes from lab models rather than real-world use in people.
Can Clear Aligners Release Microplastics That Impact the Patient’s Overall Health? A Systematic Review
AI summary Read the abstract
This systematic review investigates whether clear orthodontic aligners release microplastics during use in the mouth. The findings raise concerns about a previously overlooked source of direct microplastic exposure, since millions of people wear these plastic devices against their teeth and gums for months or years at a time.
Research digests by email
When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.