Table 2.
Home-care oral products and clinical dental materials known to release MNPs (Di Spirito et al. 2025; Wang et al. 2025; Saiyed et al. 2025)
| Product Type | Microplastic Type Released | Particle Size Range | Context of Use | Estimated Quantity Released | Exposure Route | Evidence grade (A–D) |
|---|---|---|---|---|---|---|
| Toothbrush bristles | Polypropylene (PP), nylon (PA), PET (depends on bristle material); fragments from bristle wear | Mostly < 100 µm; many 0–50 µm (PP bristles) | Daily brushing abrasion | ≥ 23.3 × 105 particles/year/person (model/simulation; varies by material and method) | Ingestion (swallowed with saliva); minimal inhalation | C |
| Toothpaste (dentifrice) | Polyethylene (PE) microbeads or fragments (where present); PEVA/EVA, PET, PP, PTFE, PMMA reported as additives (product-dependent) | Typically ~ 10–200 µm (irregular fragments; few spherical microbeads) | Brushing (ingredient in paste) | Up to 11.83 × 105 particles/year/person (brand-dependent); one study reported PE ~ 22% and PEVA ~ 78% | Ingestion (partial swallowing during brushing) | C |
| Dental floss | PTFE (Teflon) filaments, UHMW-polyethylene, or waxed nylon strands (product-dependent) | Fibres/fragments (nano- to ~ 100 µm range) | Flossing (friction against teeth/restorations) | Not quantified (limited direct particle-count data; microscopy suggests shedding) | Ingestion (fragment swallowed with saliva) | D |
| Mouthrinse microcapsules | Polymeric microcapsules/microbeads in some specialty formulations (many phased out; formulation-dependent) | Tens to few hundred µm (if present; may dissolve or disintegrate) | Rinsing (flavor/active microcapsules in select products) | Not quantified; likely minor in current formulations (market-dependent) | Ingestion (if residual rinse swallowed) | D |
| Composite resin (filling) | Methacrylate-based resin matrix (e.g., Bis-GMA/UDMA/TEGDMA systems) with inorganic filler; wear debris from finishing/polishing | Ultrafine aerosol peak ~ 40–70 nm during high-speed polishing; larger debris < 100 µm also generated | Finishing/polishing of restorations (drilling, grinding) | > 106 particles/cm3 (breathing-zone aerosol number concentration during polishing; includes resin/filler particles; polymer confirmation varies by study) | Inhalation (aerosol by dentist & patient); ingestion (particles mix with saliva) | C |
| Denture base (PMMA) | Polymethyl methacrylate acrylic (PMMA) | Mostly microparticles < 50 µm | Trimming and polishing of dentures/prostheses | Not quantified; visible acrylic dust generated per adjustment; fine particles settle on surfaces | Inhalation (technician/dentist during grinding); ingestion (settled particles in oral cavity) | C |
| Polishing paste (prophy) | Polymer microbeads/capsules in some polishing formulations (where used); fragments during use | ~ 10–100 µm (if polymer abrasives are present) | Professional tooth polishing (during dental cleaning) | Not quantified; polymer residues may be captured in suction filters/traps (study-dependent) | Ingestion (swallowed with saliva/rinse); inhalation (splatter aerosol) | D |
| Polishing cup (prophy cup) | Synthetic elastomer (rubber/silicone-based; product-dependent) | ~ 10–500 µm (abrasive wear debris) | Professional tooth polishing (rotating cup on teeth with paste) | Not quantified; minor polymer wear per use may contribute to aerosol/trap debris | Ingestion (via saliva); inhalation (rubber dust aerosol) | D |
| Clear aligner (orthodontic) | Thermoplastic polymer (PET-G, polyurethane; product-dependent) | ~ 5–20 µm (majority of particles); occasional < 5 µm | Continuous intraoral wear (plus trimming of aligners) | ~ 1.1 × 103–5.8 × 103 particles per aligner over usage period (in vitro aging/wear studies) | Ingestion (fragments in saliva swallowed); inhalation (during trimming/polishing of aligner) | C |
| Disposable suction tip | Polyethylene or polypropylene (often with other polymers; product-dependent) | Not quantified during use; secondary MPs formed via environmental fragmentation; fine particles possible with thermal degradation | Saliva ejector/high-volume suction (single-use device; plastic waste) | No direct shedding quantified during use; contributes to secondary MPs via waste stream (disposal-dependent) | Environmental pathway (secondary exposure via waste handling/disposal) | D |