Overview
EN ISO 17254:2016 (ISO 17254:2016) - "Dentistry - Coiled springs for use in orthodontics" - specifies how to characterize, test, package and label coiled springs used in orthodontic appliances. Adopted by CEN as a European Standard, it provides standardized test methods and declaration requirements so clinicians and manufacturers can compare physical and mechanical properties of orthodontic springs reliably.
Key topics and requirements
- Scope: Applies to coiled springs for orthodontic use and sets methods to compare physical and mechanical properties, plus packaging and labelling requirements.
- Declared properties: Manufacturers must declare dimensions, chemical composition and mechanical behaviour; declared values must match test results.
- Critical dimensions: inner diameter (di), outer diameter (do), unloaded spring length (luc / lue) and total length (lt). Dimensions are reported to 0.01 mm.
- Sampling and measurement: Six specimens per batch; measurements with calipers, micrometers or optical comparators accurate to 0.005 mm; record to 0.01 mm.
- Mechanical properties: Measure elastic behaviour during unloading:
- maximum extension (εmax)
- maximum compression (cmax)
- spring loads at 80%, 60%, 40% and 20% of maximum extension/compression
- Test equipment & conditions: Mechanical testing machine calibrated for force and displacement; crosshead rate 0.5–10.0 mm/min; tests at (23 ± 2) °C (or (36 ± 1) °C for temperature-sensitive springs); specimen length (20 ± 0.2) mm or unloaded spring length if less.
- Hazardous elements: Manufacturers must state mass fractions (%) of cadmium, beryllium, lead and nickel. All alloy elements ≥0.1% by mass must be declared.
- Packaging & labelling: Packaging must protect against contamination; labelling/catalogue/insert must include composition, dimension ranges, spring design (compression/extension) and mechanical property ranges.
Practical applications and users
- Who uses it: Spring manufacturers, dental product suppliers, orthodontic laboratories, clinicians, procurement teams, conformity assessors and regulatory authorities.
- Why it’s useful: Enables consistent specification and comparison of orthodontic springs, supports quality control and regulatory compliance, and helps clinicians select springs with predictable mechanical behaviour for treatment planning.
- Benefits: Improves product interoperability, reduces variability in clinical performance, and provides clear labelling and packaging guidance for safe handling and storage.
Related standards
- ISO 1942 - Dentistry - Vocabulary (terms/definitions referenced)
- ISO 10993-1 and ISO 7405 - for biological/toxicological hazard assessment (referenced guidance)
Keywords: EN ISO 17254:2016, ISO 17254, coiled springs, orthodontics, orthodontic springs, test methods, mechanical properties, dental materials, packaging and labelling.