Overview
EN ISO 15841:2014 (ISO 15841:2014) - "Dentistry - Wires for use in orthodontics" - specifies requirements and test methods for wires used in fixed and removable orthodontic appliances. The standard covers preformed orthodontic archwires but explicitly excludes springs and other preformed components. It defines how manufacturers must present physical and mechanical properties, required test methods, and packaging and labelling information for orthodontic wires.
Key topics and technical requirements
- Scope and classification
- Applies to wires for fixed and removable orthodontic appliances; excludes springs/other preformed parts.
- Wires are classified by elastic behaviour: Type 1 (linear elastic on unloading up to 50 °C) and Type 2 (nonlinear elastic on unloading up to 50 °C).
- Dimensions
- Cross-sectional dimensions (diameter, width, height, diagonal) stated to the nearest 0.01 mm; multistrand wires reported as internal tube dimensions.
- Measurement devices must have accuracy of 0.005 mm (callipers, micrometers, optical comparators).
- Mechanical properties
- Manufacturers must declare properties verified by testing. For Type 1 wires: modulus of elasticity (GPa), 0.2% proof strength (MPa), elongation at fracture (%), force-deflection rate (N/mm), and 0.1 mm offset bending force (N).
- For Type 2 wires: unloading force magnitudes at deflections of 3.0, 2.0, 1.0 and 0.5 mm and permanent deflection after unloading.
- Different wire segments with different properties must be tested and reported separately.
- Austenite-finish temperature (Taf)
- For Type 2 (shape‑memory) wires, Taf shall be reported to the nearest 1 °C, determined by differential scanning calorimetry (DSC) or by bend-and-free-recovery per ASTM F2082.
- Chemical hazards
- Manufacturer must state mass-fraction concentrations for designated hazardous elements: cadmium, beryllium, lead, and nickel.
- Testing and sampling
- Sampling requires six specimens from a single batch; manufacturer-recommended heat treatment (if any) is applied before testing.
- Packaging and labelling
- Standard defines required user information on packaging and labelling to ensure traceability and safe clinical use.
Applications and users
- Intended for orthodontic wire manufacturers, quality control and testing laboratories, regulatory authorities, procurement specialists, and clinicians/orthodontists who need consistent, comparable product data.
- Useful for product specification, compliance testing, clinical selection of archwires, and supplier benchmarking.
Related standards
- ISO 1942 (dental vocabulary)
- ISO 6892-1 (tensile testing)
- ASTM F2082 (bend and free recovery for NiTi transformation temperature)
- ISO 10993 and ISO 7405 (biological hazard assessment guidance referenced in the ISO 15841 introduction)
Keywords: EN ISO 15841:2014, ISO 15841:2014, orthodontic wires, archwires, austenite finish temperature, wire testing, orthodontics, mechanical properties, packaging and labelling.