DOUBLE ACIDIFIED SURFACE - DAS®

1) Reduced risk of contamination with foreign microparticles
2) Excellent osseointegration capabilities

The DAS surface (found on the bodies of all Leader Medica implants) is a double-acid-etched surface. This surface is produced using a chemical method that employs acid mixtures to roughen the titanium surface through material removal. The first phase involves surface activation (creating slight macro-roughness) using hydrofluoric acid. Following a series of cascade rinses with demineralized water, the actual etching process—responsible for micro-roughness—is carried out using a mixture of sulfuric and hydrochloric acids. After a further rinse, the passivation process takes place: a deep cleaning of the surface to restore the material's passive layer through the controlled introduction of oxygen, which promotes the formation of titanium oxide.

This type of surface achieves an arithmetic mean roughness (Ra) of 1.35 μm. These roughness values ​​are comparable to those of SLA (Sandblasted, Large-grit, Acid-etched) surfaces, in full agreement with the scientific literature. Indeed, as demonstrated by A. Wennerberg, long-term results for these two moderately rough surfaces are comparable. The advantage of the DAS surface (which is more costly to produce than the SLA type) is that it avoids the deposition of blasting media—often potentially harmful aluminum oxide—on the implant surface.

In the image: macro- and micro-roughness of the surface.

Decontamination
Industrial processes (turning, surface treatment, packaging) inevitably generate manufacturing residues that settle on the surface. Although the production process includes decontamination stages—such as washing and ultrasonic baths—microscopic analysis often reveals carbon or acid residues. These contaminants undoubtedly impair osteoblast cell adhesion while simultaneously triggering an inflammatory response.

The most efficient removal strategy involves a biophysical process known as plasma treatment. This technology employs ionized gases or gas mixtures to eliminate all surface contaminants from the implants. By utilizing specific settings and an argon-oxygen gas mixture, the plasma treatment applied to Leader Medica implants effectively removes organic and inorganic contaminants, rendering the surface fully prepared for interaction with bone cells.

Pictured: a contaminated system prior to treatment.

We certify surface roughness and cleanliness in-house using scanning electron microscopy (SEM) and X-ray analysis.
The protocol applied to each batch of implants was established with the contribution of Prof. Luigi Canullo, a renowned expert in the field of implant surfaces and their associated manufacturing and cleaning processes.