Overview
EN ISO 21606:2022 / ISO 21606:2022 - Dentistry - Elastomeric auxiliaries for use in orthodontics - is a European adoption of the international standard specifying requirements and test methods for elastomeric orthodontic products. It applies to elastomeric auxiliaries used both intra‑oral and extra‑oral, in conjunction with fixed and removable appliances. This second edition (2022) supersedes earlier versions and was approved by CEN as EN ISO 21606:2022.
Key topics and technical requirements
The standard defines terminology, dimensional criteria, mechanical properties and standardized test procedures for elastomeric orthodontic devices, including:
- Device types covered: orthodontic elastics, elastomeric chains, elastomeric thread, ligatures and separators (collectively “elastomeric auxiliaries”).
- Dimensions and test length: definitions such as link length, inner/outer diameters and the specified test length for each device type.
- Mechanical properties:
- Initial extension force (F0) - force at three times the test length after initial extension to four times the test length.
- 24 h residual force (F24) - force at three times the test length measured at 24 hours after initial extension, expressed as a percentage of F0.
- Ultimate extension (A) - extension at break expressed as a percentage.
- Test methods: sampling, ambient conditions, apparatus and step‑by‑step procedures for measuring dimensions, initial force, 24 h residual force and ultimate extension, plus treatment of results.
- Marking, labelling and packaging: general requirements for product information and labelling to support traceability and safe use.
- Normative references: e.g., ISO 3696, ISO 1942, ISO 8601‑1. The standard recommends referring to ISO 10993‑1 and ISO 7405 for biological hazard assessment (biocompatibility not specified in detail here).
Practical applications
EN ISO 21606:2022 is used to:
- Establish product specifications during design and development of elastomeric orthodontic devices.
- Perform type testing and quality control in manufacturing and laboratory settings.
- Provide consistent, comparable data for clinical decision‑making and supplier/product comparisons (force decay, elongation at break).
- Support regulatory compliance, technical dossiers and CE marking in the EU market.
Who should use this standard
- Manufacturers of orthodontic elastomeric products
- Quality managers and test laboratories in dental materials
- Regulatory affairs professionals and conformity assessors
- Orthodontists and dental procurement teams evaluating product performance
Related standards
EN ISO 21606:2022 provides a consistent, reproducible framework for measuring and reporting performance of elastomeric orthodontic auxiliaries, enabling reliable product comparison, quality assurance and safer clinical use.