YY/T 1860.1-2024 Non-active surgical implants - Implant coating - Part 1: General requirements
1 Scope
This document specifies general requirements for implant coatings, comprising both surface coatings and surface modifications, applied to non-active surgical implants. This document specifies requirements concerned with generic coating properties including chemical and phase compositions, surface texture, coating coverage integrity, dissolvability, coating thickness, adhesion strength, abrasion resistance, porosity and pore size, and surface wettability.
This document is applicable to surface coatings, which are defined as layers of material with any different property than the natural surface of the substrate which are intentionally added to the substrate.
This document is applicable to surface modifications, which are defined as intentional conversion or reconstruction of the surface of the original substrate to form a new surface material consisting of components of the substrate’s own material and possibly foreign material and forming a surface layer with different properties.
Since the pertinent properties of a coating and their needed level of characterization are highly dependent on the intended application of the implant, the generic nature of the general requirements in this document is not intended to either override or replace the provisions of application-specific performance standards.
This document is not applicable to surfaces modified by texturing with the exclusive intention to change the roughness of the surface or the strength of the raw material.
This document is not applicable to natively passivated metal surfaces. While this document is applicable to intentionally passivated metal surfaces, well-established materials passivated by conventional techniques, such as nitric acid immersion, are usually non-hazardous and can be described in a very basic manner.
This document is not applicable to implant coatings utilizing viable tissue.
This document is not applicable to laminates, i.e. composite materials made of multiple layers, e.g. vascular prosthesis constructed of different expanded polytetrafluoroethylene layers, except the exposed surface of the laminate, which can be an implant coating (see 3.1, note 2).
This document is not applicable to coverings, e.g. covered stents.
Note 1: This document does not contain requirements on biocompatibility. Nevertheless, this is a critical property of the device and coating and needs to be addressed during risk assessment.
Note 2: This document supplements applicable non-active surgical implant standards and YY/T 0640.
Note 3: This document does not require that manufacturers have a quality management system in place. However, the application of a quality management system, such as that described in ISO 13485, could be appropriate to help ensure that the implant achieves its intended performance.
Note 4: Although fully porous implants are not coatings, some of the considerations in this document can also be applied to them.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
YY/T 0640 Non-active surgical implants - General requirements (YY/T 0640-2016, ISO 14630: 2012, IDT)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in YY/T 0640 as well as the followings apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
——IEC Electropedia: available at http://www.electropedia.org/
——ISO Online browsing platform: available at http://www.iso.org/obp
3.1
implant coating
surface coating (3.2) or surface modification (3.3)
Note 1: Implant coating is considered a constituent of an implant.
Note 2: A laminate, i.e. a composite material made of multiple layers of the same or different materials with the same or different internal structures assembled sandwich-like and bonded by heat, pressure, welding, soldering or adhesives, is not in itself considered an implant coating. But the exposed surface of the laminate can be an implant coating.
Note 3: A covering, for example additional material (e.g. a graft) added to a structure (e.g. a stent) specifically to bridge elements of the structure for the sole purpose of reducing the permeability of the structure, is not considered an implant coating.
3.2
surface coating
layer of material with any different property than the natural surface of the substrate that is intentionally added to the substrate
Note 1: The coating can partially or fully cover the substrate surface.
Note 2: The term includes surface coatings created as a result of additive manufacturing.
3.3
surface modification
intentional conversion or reconstruction of the surface of the original substrate to form a new surface material consisting of components of the substrate's own material and possibly foreign material and forming a surface layer with different properties
3.4
coating property
measurable characteristic of a coating
Note 1: A coating property can for example be mechanical, physical, chemical or morphological / microstructural in nature.
Note 2: In multi-layered coatings, one or more characteristics are designed to change along the coating depth with one or more corresponding interfaces. These characteristics are also considered coating properties.
Note 3: In gradient coatings, one or more characteristics are designed to change (increase or decrease in magnitude of a particular property) along the coating depth without interfaces. These characteristics are also considered coating properties.
Foreword i
Introduction ii
1 Scope
2 Normative references
3 Terms and definitions
4 General requirements
Annex A (Informative) Coating technology examples
Annex B (Informative) Examples of intended functions of implant coatings
Annex C (Informative) Standards with information related to coatings
Bibliography
