strumenti chirugici per impianti dentali realizzazione soprastrutture viti impianto kit chirurgico Implant Surface

 Implant surface

Surface processing of the fixtures calls for two separate stages:

• Roughening of the surface: during which the screw is given a controlled degree of roughness
• Cleaning of the surface: during which all contaminants and foreign elements are removed. Both stages use advanced technology enabling state-of-the-art specifications to be met. 

Surface roughening

The morphology of the surface of Primer S.R. implants is controlled by means of a roughing process with acids followed by treatment with bases. The resulting surface presents a high concentration of oxydrilic surface groups, the importance of which in mineralisation processes is recognised in several recent theories.

• The surface roughness is of the order of microns, with a peak-to-peak distance smaller than the size of a cell. The data in literature at our disposal [4-6-10-11-12] indicate that, regardless of the manner in which it is obtained, this is the best surface currently available for obtaining osteointegration.
• Modification of the surface is carried out by means of a removal process in which no material is added and therefore no potential problems of detachment are generated. Furthermore, there is no sanding, which often causes the presence of residues on the implant surface. Complete removal of process contaminants is ensured by a very thorough cleaning protocol calling for washing in apyrogenous water and decontamination by means of plasma treatment.

Chemical composition

Control of the chemical composition of the surface, in particular in the fundamental stage of the decontamination process, has reached high levels of effectiveness and reproducibility thanks to the introduction of advanced specific processes.

Surface cleaning

Cleaning of the surfaces of titanium implants is an important and complex operation.

The processes for manufacturing fixtures [turning, surface finishing] may leave traces of dirt or foreign substances, that can interfere with the healing process of the bone. Conventional cleaning operations with solvents do not guarantee complete cleaning. This is because even very pure solvents can leave traces on the underlying surface. The few impurities present or the molecules of the solvent itself could combine with the substances making up the surface, especially in the case of materials as reactive as titanium.

The ideal cleaning method should be incapable of reacting chemically with the implant and, at the same time, be very effective in removing any contaminants present on it. With plasma cleaning it is possible to apply this ideal principle. This technology originated in the world of microelectronics and had been successfully transferred to the field of medical devices.

Plasma cleaning has now been adopted by the leading manufacturers in this field.

Plasma cleaning is carried out in special reactors at a pressure lower than atmospheric pressure, using electrical fields that cause the acceleration of charged particles and partial ionisation of the gas introduced into the reactor. Argon is the gas most commonly used for these cleaning operations, although it is also possible to use air or oxygen.

The devices to be cleaned are placed in a reactor and the plasma is ignited. The material is thus surrounded by an inert gas atmosphere that contains ions, electrons and a whole range of chemical species. Accelerated by the electrical field present in the plasma, these strike the surface subjecting it to genuine bombardment. The cleaning action is generated by the physical effect of the bombardment, which causes organic contaminants to become detached from the surface and be removed, and enables clearing to a degree that cannot be equalled by other techniques. The process parameters can be closely controlled and adapted to the specific material or device to be cleaned, ensuring reproducibility of the effect and very constant quality.