Roughness analysis of breast prostheses by PO3D

Distinguish the type of breast prosthesis (smooth, textured...) thanks to 3D profilometry


 

In recent years, several scandals concerning medical prostheses have highlighted the failure of certain health authorities in controlling implants. One of the most widely known cases in France involved a company manufacturing breast prostheses made from fraudulent industrial silicone.

This case revealed the lack of medical devices oversight in the public health. It also reminded us of the importance of the various physicochemical tests on these implants.

As a result, a temporary specialised scientific committee was set up in 2015 within the ANSM. They founded a connection between the roughness of the external surface of breast implants and the increase in cases of certain lymphomas in people who wear or have worn prostheses with a textured external surface. Different types of breast implants exist, four of which are distinguished by manufacturers according to their surface texturing: "smooth", "micro textured", "macro textured" and "textured". The roughness allows for a better grip of the prosthesis which thus has an increased adhesion with the tissues, thus avoiding its displacement or rotation.

ISO 25178 is a set of international standards defining the analysis of 3D surface conditions. 

This standard is used to characterise the "Geometrical Product Specification (GPS)" and roughness parameters of breast forms. It also lists the different measurement techniques that can be used, including confocal and interferometric microscopy. Optical profilometry is a non-contact imaging method for observing and characterising surface topography over measurement ranges from a few tens of µm² to a few mm², with a lateral resolution of 200 nm and depth resolutions from nm to several mm. A standard analysis provides 2D and 3D images of the surface with the dimensions of the observed features, as well as all the roughness parameters defined by the standard.

Optical profilometry provides a characterisation of the topography of surfaces (a few tens of µm² to a few mm²) whatever the sample, regardless of the material analysed, its shape or its colour.

Several modes can be used to access different degrees of information. Confocal microscopy can image all types of samples (flat or very rough, slopes up to 70%). On smooth surfaces, interferometry allows to reach nanometric vertical resolutions.

TESCAN ANALYTICS has a recognized expertise in the use of PO3D on all types of materials. Our team of experts works with all industrial sectors.


 

Objective of the analysis


Measurement of the roughness of the external surface of a breast prosthesis and its surface parameters.
 

Sample preparation


The breast prosthesis shell is cut into a 1 cm square and placed directly under the PO3D microscope without further manipulation.

Results


Figure1-(1).png

Figure 1: 3D view of the surface roughness of the outer surface of a breast prosthesis

Tableau-1VF.png

Figure 2: Summary table of surface roughness parameters of the external surface of a breast prosthesis

 

3D optical profilometry allows non-destructive (non-contact) measurement of the surface relief of the sample in order to evaluate its roughness parameters.

Image1-(1).png

In figure 1, the PO3D allows the visualisation of the 3D topography of the outer surface of the prosthesis. In this image, the arithmetic mean height is 66.4 µm. It is also possible to visualise the morphology of the relief. 

Figure 2 shows the surface roughness parameters calculated over the entire surface analysed and not by an average calculated over several base lengths as in 2D. Here, the parameters of interest to distinguish smooth, macrotextured, textured and microtextured prostheses are mainly Sa, Sq and Sv.

Summary


In this example, it was demonstrated that PO3D is a suitable microscopy tool for the measurement of surface roughness parameters of interest, necessary for the identification of the class of breast prosthesis.

PO3D allows the classification of breast prostheses according to their surface texturing.

For more applications of PO3D analysis or our other techniques, please ask us for information.

Other complementary techniques can be used to study roughness and surface parameters such as 3D SEM.