Overview
EN ISO 23401-1:2023 - "Dentistry - Chairside denture base relining materials - Part 1: Hard type materials" is a CEN-endorsed international standard that specifies requirements and test methods for acrylic hard type chairside denture relining materials. It covers material composition (acrylic and methacrylic monomers and polymers), sampling, testing, packaging, marking and manufacturer instructions. The standard applies only to acrylic dentures relined chairside and is not applicable to laboratory-use relining materials or soft lining materials.
Key topics and requirements
- Scope and classification
- Defines the hard-type classification and limits application to acrylic denture bases.
- Material composition
- Notes that hard-type materials contain acrylic/methacrylic monomers (e.g., (meth)acrylic esters) and their polymers.
- Performance requirements
- Visual appearance, consistency for intra-oral handling, peak exothermic temperature during polymerization, porosity and defects, surface finish.
- Physical properties testing: water sorption, water solubility, and Knoop hardness.
- Test methods and specimen preparation
- Detailed procedures for sampling, specimen preparation, conditioning and testing (consistency, peak temperature, sorption/solubility, hardness).
- Packaging, marking and instructions for use
- Requirements for labeling, user instructions and safe handling information to be supplied by the manufacturer.
- Safety and biological considerations
- While specific toxicological limits are not provided, the standard recommends referencing ISO 10993-1 and ISO 7405 for biological evaluation.
Practical applications
- Manufacturers: Use EN ISO 23401-1:2023 to design, test and certify chairside hard relining products to meet harmonized European and international quality requirements.
- Regulators and conformity assessors: Adopt this standard for product approval, market surveillance and regulatory compliance checks.
- Dental clinicians and prosthodontists: Understand material performance expectations (handling, intra-oral polymerization temperature, durability) when selecting chairside acrylic relining systems.
- Purchasing and procurement: Specify compliant materials in tenders and procurement to ensure safety and consistent clinical performance.
Related standards
- ISO 10139-1 / ISO 10139-2 - standards for soft lining materials (distinct from this hard-type document).
- ISO 20795-1 / ISO 20795-2 - denture base material standards with different polymerization and property requirements.
- ISO 10993-1 and ISO 7405 - guidance for biological and toxicological evaluation of dental materials.
Keywords: EN ISO 23401-1:2023, chairside denture base relining materials, hard type materials, acrylic relining, dentistry standards, test methods, water sorption, Knoop hardness.