Final Report Summary - NEWTRESI (New treatments for surgical implants)
The ultimate aim of the NEWTRESI project was to work towards improved coatings for a specialised range of implants which would improve European healthcare. The main objectives of the project were to:
- set-up a new thin film treatment for dental and orthopaedic titanium surgical implant able to reduce of at least 50 % the time necessary to obtain a complete integration into the bone and able to protect the titanium implants against the erosion of the body fluids;
- develop a new sealing structure for electronic endocochlear surgical implant able to replace the actual alumina case but reducing the thickness and the cost;
- develop a new biocompatible sealing structure for electronic pressure sensors, for intrauterine and intraocular measurements.
Regarding the first objective, the deposition process utilised to obtain the best results was the Ion plating plasma assisted (IPPA) along with the reactive magnetron sputtering source but good preliminary results were also obtained using reactive arc source deposition. The target of this activity was completely reached with a more than 50 % reduction in the osseointegration time, evaluated both with in vitro and in vivo tests. The treatment was very adherent dense and stable. The deposition process was highly controllable and repeatable. The forecast production cost for dental implant treatment seemed to be definitely low.
In the second objective, the sealing structure was based on the following elements (including the electronic microcircuit): the electronic circuit, the planarising-sticking high-vacuum resin, a glass frame (with small holes for connecting wires, if necessary) of about the same total thickness of electronic microcircuit, two glass microsheets (around 0.1 mm thick) as top and bottom of the case. The high-vacuum resin would act both as a planarising element, as well as a bonding and sealing element (a very thin layer of resin must be also distributed on the surfaces between the glass frame and the microsheets), giving robustness to the microsheets glasses and to the whole structure. The target of this activity was completely reached but using a solution partially different from that originally planned. In fact, the multilayer barrier structure, that seemed to be too difficult and expensive to realise, was replaced by a glass (or quartz) micro sheet ( around 0.1 mm thick) closely bonded with the planarising high-vacuum resin layer and laterally closed by a simple glass frame. The total structure (that can be only 0.2 mm thicker than the electronic microcircuit) was robust (up to be mechanically reworkable) stable and biocompatible. The sealing fulfilled the specifications and the expected production cost seemed to be considerably lower than the actual solution.
Furthermore, regarding the third objective of the project, the barrier structure was composed by a multilayer inorganic-organic-inorganic SiNy/SiOC/SiNy deposited by High-density plasma enhanced chemical vapour deposition ((HDPECVD) was first optimised by treating plastic substrates to evaluate the adherence and the barrier effect. The target of this activity was reached but just for the intrauterine pressure sensors. The sensitivity of the coated sensors remained unchanged. The research activity for intraocular sensors gave not satisfactory results because strong of the difficulties faced in depositing barrier layers on the silicone resin of the surface of the sensor and also because only very few samples to treat were available.
- set-up a new thin film treatment for dental and orthopaedic titanium surgical implant able to reduce of at least 50 % the time necessary to obtain a complete integration into the bone and able to protect the titanium implants against the erosion of the body fluids;
- develop a new sealing structure for electronic endocochlear surgical implant able to replace the actual alumina case but reducing the thickness and the cost;
- develop a new biocompatible sealing structure for electronic pressure sensors, for intrauterine and intraocular measurements.
Regarding the first objective, the deposition process utilised to obtain the best results was the Ion plating plasma assisted (IPPA) along with the reactive magnetron sputtering source but good preliminary results were also obtained using reactive arc source deposition. The target of this activity was completely reached with a more than 50 % reduction in the osseointegration time, evaluated both with in vitro and in vivo tests. The treatment was very adherent dense and stable. The deposition process was highly controllable and repeatable. The forecast production cost for dental implant treatment seemed to be definitely low.
In the second objective, the sealing structure was based on the following elements (including the electronic microcircuit): the electronic circuit, the planarising-sticking high-vacuum resin, a glass frame (with small holes for connecting wires, if necessary) of about the same total thickness of electronic microcircuit, two glass microsheets (around 0.1 mm thick) as top and bottom of the case. The high-vacuum resin would act both as a planarising element, as well as a bonding and sealing element (a very thin layer of resin must be also distributed on the surfaces between the glass frame and the microsheets), giving robustness to the microsheets glasses and to the whole structure. The target of this activity was completely reached but using a solution partially different from that originally planned. In fact, the multilayer barrier structure, that seemed to be too difficult and expensive to realise, was replaced by a glass (or quartz) micro sheet ( around 0.1 mm thick) closely bonded with the planarising high-vacuum resin layer and laterally closed by a simple glass frame. The total structure (that can be only 0.2 mm thicker than the electronic microcircuit) was robust (up to be mechanically reworkable) stable and biocompatible. The sealing fulfilled the specifications and the expected production cost seemed to be considerably lower than the actual solution.
Furthermore, regarding the third objective of the project, the barrier structure was composed by a multilayer inorganic-organic-inorganic SiNy/SiOC/SiNy deposited by High-density plasma enhanced chemical vapour deposition ((HDPECVD) was first optimised by treating plastic substrates to evaluate the adherence and the barrier effect. The target of this activity was reached but just for the intrauterine pressure sensors. The sensitivity of the coated sensors remained unchanged. The research activity for intraocular sensors gave not satisfactory results because strong of the difficulties faced in depositing barrier layers on the silicone resin of the surface of the sensor and also because only very few samples to treat were available.