Micro and nanoplastics in dentistry: emerging sources, health implications, and mitigation pathways: a narrative review

Micro and nanoplastics (MNPs) released from dental materials and oral-care products are an emerging concern at the intersection of dentistry and environmental health. This narrative review synthesizes evidence on dentistry-related sources of MNPs, exposure pathways, biological interactions, detection approaches, and environmental dissemination, with emphasis on practical mitigation. Resin-based composites and acrylic prosthetics, as well as routine consumer products such as toothbrushes, toothpastes, floss, and clear aligners, are identified as potential sources of microscopic polymer debris. Exposure may occur during everyday use, predominantly via ingestion with saliva and, in some contexts, inhalation of fine procedure-generated aerosols. Experimental in vitro and in vivo studies indicate that MNPs can be internalized by oral cells and may trigger oxidative stress and inflammatory responses, although direct human clinical evidence linking dental-origin exposure to disease remains limited. Proposed associations with periodontal inflammation, oral carcinogenesis, or systemic outcomes are biologically plausible but unconfirmed. Environmental studies have reported polymer-containing particulate in oral-care rinse water and dental wastewater, suggesting dentistry may represent a small but potentially addressable point source of microplastic release. We summarize mitigation options including effective chairside evacuation, upstream filtration and trap maintenance, dust control for laboratory processes, and patient guidance toward lower-shedding products, and we note the relevance of evolving regulation, including the EU REACH 2023/2055 restriction on intentionally added microplastics.