prEN ISO 21606

• Abstract:

  This document specifies the requirements and their test methods applicable to all elastomeric auxiliaries used for orthodontics both inside and outside the mouth, in conjunction with fixed and removable appliances.

• Status: Not Published
• Publication Date: 19-Dec-2027
• ICS: 11.060.10 - Dental materials
• Technical Committee: CEN/TC 55 - Dentistry
• Current Stage: 4060 - Closure of enquiry - Enquiry
• Start Date: 14-Aug-2026
• Completion Date: 14-Aug-2026
• Ref Project: oSIST prEN ISO 21606:2026 - Dentistry - Elastomeric auxiliaries for use in orthodontics (ISO/DIS 21606:2026)

• Revises: EN ISO 21606:2022 - Dentistry - Elastomeric auxiliaries for use in orthodontics (ISO 21606:2022)
• Effective Date: 12-Nov-2025

Overview

prEN ISO 21606:2026 - Dentistry - Elastomeric auxiliaries for use in orthodontics (ISO/DIS 21606:2026), developed under the auspices of CEN and ISO, sets the requirements and test methods for all elastomeric auxiliaries used in orthodontics, both intraorally and extraorally. This standard applies to auxiliaries used in conjunction with fixed and removable orthodontic appliances, and supports dental professionals, manufacturers, and suppliers by standardizing terminology, performance, and labelling for products such as elastomeric ligatures, elastomeric chains, orthodontic elastics, elastomeric threads, and separators.

Key Topics

• Scope of Products:

  • Covers elastomeric auxiliaries like orthodontic elastics, elastomeric chains, threads, ligatures, and separators.
  • Applies to auxiliaries utilized within or outside the mouth, in fixed or removable appliances.

• Performance Requirements:

  • Specifies testing for dimensions and mechanical properties (initial extension force, 24-hour residual force, and ultimate extension).
  • Ensures product characteristics align with manufacturer specifications for safety, reliability, and effectiveness.
  • Mechanical property requirements are assessed through standardized type tests under controlled conditions.

• Test Methods:

  • Detailed procedures for sampling, handling, and mechanical testing of specimens.
  • Use of calibrated equipment to verify compliance with product specifications.
  • Ensures consistent assessment across different batches and manufacturers.

• Marking, Labelling, and Packaging:

  • Mandates clear labelling with product name, dimensions, lot number, intended use, expiry date (ISO 8601-1 format), storage conditions, and manufacturer or distributor information.
  • Requires packaging to prevent contamination and maintain product integrity during transit and storage.
  • Highlights the need for warnings if products contain hazardous elements.

• Terminology:

  • Standardizes definitions for terms such as elastic, chain, thread, ligature, separator, and associated dimensional characteristics.
  • Provides a basis for consistent communication and understanding among dental professionals and manufacturers.

Applications

• Orthodontic Treatment:

  • Ensures elastomeric auxiliaries used in teeth movement are safe and perform as intended in both fixed and removable orthodontic appliances.
  • Supports clinical effectiveness by requiring clear information on product properties and performance.
  • Enables orthodontists to make informed choices and compare products based on standardized information.

• Product Manufacturing and Quality Assurance:

  • Guides manufacturers in developing and testing products to internationally recognized benchmarks for dental materials.
  • Facilitates type testing to confirm that products remain within specified dimensional and mechanical ranges.

• Regulatory Compliance:

  • Assists regulatory bodies in evaluating orthodontic auxiliaries for safety, efficacy, and labelling, supporting public health and patient safety.
  • Provides a framework for referencing in national or regional regulations regarding dental materials.

Related Standards

• ISO 10993-1: Biological evaluation of medical devices - Fundamental requirements for risk management pertaining to biocompatibility.
• ISO 7405: Dentistry - Evaluation of biocompatibility for dental-specific medical devices.
• ISO 1942: Dentistry – Vocabulary - Authoritative reference for terminology used throughout dental standardization.
• ISO 3696: Water for analytical laboratory use - Specification for water quality needed during product testing.
• ISO 8601-1: Representation of date and time information, ensuring unambiguous expiry dates on packaging.

prEN ISO 21606:2026 contributes directly to the safety, traceability, and standardized performance of elastomeric auxiliaries in orthodontics, enabling global dental professionals and manufacturers to meet high standards of patient care and regulatory compliance.

SLOVENSKI STANDARD
01-julij-2026
Zobozdravstvo - Elastomerni pripomočki za uporabo v ortodontiji (ISO/DIS
21606:2026)
Dentistry - Elastomeric auxiliaries for use in orthodontics (ISO/DIS 21606:2026)
Zahnheilkunde - Elastomeres Zubehör für die Kieferorthopädie (ISO/DIS 21606:2026)
Médecine bucco-dentaire - Auxiliaires élastomériques utilisés en orthodontie (ISO/DIS
21606:2026)
Ta slovenski standard je istoveten z: prEN ISO 21606
ICS:
11.060.10 Zobotehnični materiali Dental materials
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
International
Standard
ISO/DIS 21606
ISO/TC 106/SC 1
Dentistry — Elastomeric auxiliaries
Secretariat: AFNOR
for use in orthodontics
Voting begins on:
Médecine bucco-dentaire — Auxiliaires élastomériques utilisés en
2026-05-22
orthodontie
Voting terminates on:
ICS: 11.060.10 2026-08-14
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS.
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Reference number
ISO/DIS 21606:2026(en)
DRAFT
ISO/DIS 21606:2026(en)
International
Standard
ISO/DIS 21606
ISO/TC 106/SC 1
Dentistry — Elastomeric auxiliaries
Secretariat: AFNOR
for use in orthodontics
Voting begins on:
Médecine bucco-dentaire — Auxiliaires élastomériques utilisés en
orthodontie
Voting terminates on:
ICS: 11.060.10
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2026
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
BE CONSIDERED IN THE LIGHT OF THEIR
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
or ISO’s member body in the country of the requester.
NATIONAL REGULATIONS.
ISO copyright office
RECIPIENTS OF THIS DRAFT ARE INVITED
CP 401 • Ch. de Blandonnet 8
TO SUBMIT, WITH THEIR COMMENTS,
CH-1214 Vernier, Geneva
NOTIFICATION OF ANY RELEVANT PATENT
Phone: [phone]
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Email: [e-mail]
Website: www.iso.org
Published in Switzerland Reference number
ISO/DIS 21606:2026(en)
ii
ISO/DIS 21606:2026(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Requirements . 3
4.1 General .3
4.2 Dimensions .3
4.3 Mechanical properties .3
4.3.1 Initial extension force .3
4.3.2 24 h residual force.3
4.3.3 Ultimate extension .3
5 Test methods . 4
6 Marking, labelling and packaging . 7
6.1 General requirements .7
6.2 Packaging and labelling .7
Bibliography . 8

iii
ISO/DIS 21606:2026(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent
rights identified during the development of the document will be in the Introduction and/or on the ISO list of
patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 106, Dentistry, Subcommittee SC 1, Filling and
restorative materials, in collaboration with the European Committee for Standardization (CEN) Technical
Committee CEN/TC 55, Dentistry, in accordance with the Agreement on technical cooperation between ISO
and CEN (Vienna Agreement).
This third edition cancels and replaces the second edition (ISO 21606:2022), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— Change in test apparatus in 5.4.1.2 from two half-rods or rods to two shepherd’s hooks.
— Change in Figure 2 to reflect the change from two half-rods or rods to two shepherd’s hooks.
— Change in procedure of 5.5.2 to reflect that the shepherd’s hooks will be held in place by a locking
collar during transfer to the constant temperature bath rather than moving the extended elastomeric
auxiliaries without any relaxation to the support plate for storage in the constant temperature bath.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
ISO/DIS 21606:2026(en)
Introduction
This document has been developed as a result of the difficulty often encountered by clinicians in making
meaningful comparisons between elastomeric auxiliaries using the information currently available from
manufacturers and suppliers.
NOTE Auxiliaries include orthodontic elastics, orthodontic elastomeric chains, orthodontic thread, orthodontic
elastomeric ligatures and orthodontic elastomeric separators.
Specifi
...