For the morphological analysis, a test setup based on Jewell et al. 2018 was constructed. The setup consists of a sliding table that holds the breast implant sample. The sliding table is moved so that the specimen touches the stationary plate stop. The movable plate stop is connected to a horizontal caliper to measure the width of the implant. A digital height gauge is mounted next to the setup to measure projection and pole depth. The setup also allows assisted vertical alignment of the specimen.

Measured parameters include width, height, lower pole depth, and upper pole depth for anatomically shaped implants, and height, overhang, and upper pole depth for round implants. Each parameter is measured three times per device, with the implant removed and repositioned between measurements. The maximum projection for anatomically shaped implants is defined as the depth of the lower pole in a horizontal position, and the maximum projection for round implants is defined as the apex in the center of the device. The upper pole depth is the thickness of the upper pole, defined as 17% of the average horizontal height measured from the top of an anatomically shaped implant, or 25% of the average horizontal height measured from the top of a round implant.

Reference: Jewell ML, Bengtson BP, Smither K, Nuti G, Perry T. Physical Properties of Silicone Gel Breast Implants. Aesthet Surg J. 2019 Feb 15;39(3):264-275

For the peel test, a universal testing machine with a 100 N load cell and a hydraulic clamp is used. The test setup also includes a flat base plate on which the test specimen is placed. For preparation, lines are drawn on the shell of each specimen at 1-inch intervals using a permanent marker, and the implant is cut along these lines with a razor blade.

The test specimen is placed on the base plate in the testing machine, and one inch of the elastomeric shell is peeled away from the gel. The now free end of the shell is clamped in the machine’s hydraulic clamp and adjusted so that the force is evenly distributed across the cross-section of the specimen. The force is zeroed, and the elastomeric shell is pulled at a speed of 20 inches per minute.

The maximum force required to separate the shell from the gel is measured. The number of measurements per specimen depends on the surface area of the sample but should be at least two. The recorded maximum force values are then averaged.

For the gel compression fracture test, a universal testing machine equipped with a 100 N load cell and a compression platen with a diameter of 15 mm is used. The test setup includes a flat plate on which the sample is placed. Compression is applied at a speed of 1 inch per minute. The compressive force exerted on the gel is measured until a drop in force indicates the point of gel fracture. A higher compressive force indicates greater resistance to gel fracture.

The testing of gel material properties is conducted using our proprietary BTC-2000 device. The suction unit, which holds the laser unit, is mounted on a microscope stand with a micrometer drive. A scale is positioned on the microscope stand. The basic principle of gel elasticity testing involves applying a vacuum to a portion of the implant gel inside the cylindrical chamber of the suction unit and measuring the gel deformation with a laser. A 1 cm circular area of the implant shell is removed from the apex of the implant, and the gel is dusted with laser toner to enhance laser tracking of the surface.

The implant sample is placed on the scale, which is then tared. The cylindrical BTC test chamber is lowered onto the gel surface using the micrometer drive until a force of 5 g is registered on the scale. A vacuum is applied in the suction unit at a rate of 1 millimeter of mercury (mm Hg) per second until reaching 15 mm Hg. Deformation (mm) and pressure (mm Hg) values are recorded.

The resulting value, called “elastic deformation,” is defined as the deformation measured at maximum vacuum, representing the elastic response to the applied pressure. Higher values indicate “softness,” while lower deformations indicate “firmness.”

Reference: Kinney BM, Jeffers LLC, Ratliff GE, Carlisle DA. Silicone gel breast implants: science and testing. Plast Reconstr Surg. 2014 Jul;134(1 Suppl):47S-56S.

ASTM F703 describes a test for silicone implants to assess gel bleeding. This test checks the implant for the migration of silicone gel through the elastomer shell. The implants are placed on platinum-cured silicone discs (70 durometer) with a diameter of 50 mm and stored for 8 weeks at 43.3°C. The weight of the silicone discs is measured weekly to determine any change in weight. Control discs, stored under the same conditions without implants, are used to account for variations due to environmental factors. ASTM requires a minimum of three samples of each implant type and three additional control discs.

ISO 14607 (2007 edition) describes in section E.3 the testing of the static rupture strength of breast implants. In addition to fatigue tests according to the 2018 edition and FDA guidelines, we also offer the static rupture test according to the 2007 edition.

Please feel free to contact us if you are interested in other methods for the mechanical testing of breast implants.

The testing of surface characteristics of breast implants according to ISO 14607:2024 is used to determine the surface roughness (Sa) as well as the surface complexity (Scx). Together with the type of surface texturing, this allows classification of the implant surface.

For roughness measurements, we use a confocal laser scanning microscope. The surface topography is scanned at magnifications of 10x or 20x. In addition to the arithmetic surface roughness (Sa), we also determine further parameters upon customer request, such as root mean square height (Sq), skewness (Ssk), kurtosis (Sku), maximum peak height (Sp), maximum pit height (Sv), maximum height (Sz), or density of peaks (Spd). The surface complexity (Scx) is determined using our digital microscope VHX-7000.

We use the proven punching technique according to ISO 37 to create as flat a cross-section as possible on the implant shell for the measurements. During evaluation, the complexity of the surface texture is determined in two-dimensional space.