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Multifunctional bioresorbable biocompatible coatings with biofilm inhibition and optimal implant fixation IP-SME MEDDELCOAT 2006-2010 Background Most common reasons for revision surgery of implants are loosening (65%), dislocation (9%) and infection (7%). The revision rate of orthopaedic implants is between 10-20% after 15-20 years. For dental implants it is 15% over a 5-year period. Biofilm formation is the major pathogenic factor. Objectives The project aims at gaining the scientific and processing knowledge to develop the next generation of multifunctional, bioactive, biocompatible coatings for orthopaedic and dental implants with biofilm inhibition and optimal implant fixation. The envisaged radical innovations and major breakthroughs are: Shoulder prostheses Dental implant • New substrates and coatings with enhanced biocompatibility • Radically new or improvement of existing coating techniques for processing bioresorbable and biocompatible coatings with a graded interface and tailored porosity • In-depth understanding of implant substrate/coating/bone interface structure, design and engineering of optimal implant fixation Acetabular cups Hip implant • Knowledge on biofilm formation and inhibition • Formulation and evaluation of biofilm inhibitors incorporated into the coating Porous bioactive coating processing techniques Amongst the techniques to realise the porous bioactive coating are: • Vacuum plasma spraying • Sol-gel processing • Electrophoretic deposition • Selective laser sintering • Dip coating • Plasma Enhanced Chemical Vapour Deposition (PE-CVD) • Laser assisted microwave processing Vacuum plasma spraying CO2-laser Laser Thermal Insulation Conventional heating system Microwave source 2.45 GHz Laser supported MW plasma Substrate Electrophoretic deposition and dip-coating PE-CVD Laser assisted microwave processing Materials Ti6Al4V and CoCrMo alloys are most commonly used for orthopaedic applications, whereas pure Ti is used for dental implants. In the project, new nanostructered titanium-based alloy implant substrates will be developed and evaluated. To promote osteointegration the substrate is coated with a bioactive top layer based on calcium phosphate, bioactive glass or titania. Hydroxyapatite infiltrated vacuum plasma sprayed porous Ti coatings are used as reference material. Biofilm inhibiting coating Staphylococcal biofilms Drug delivery platform Model micro-organism systems will be used to investigate and select the most suitable antimicrobial substances active during a reasonable and optimal period to reduce infection and biofilm formation to a minimum. A suitable drug delivery platform will be designed and the controlled release of the selected anti-infectives from the new substrate-coating biomaterial systems will be studied in vitro. Expectations Reducing the need for implant revision due to loosening and infection by designing and engineering an implant surface to optimise fixation, promoting osteointegration by applying a bioactive coating and incorporating a biofilm formation inhibiting function. LEMI www.meddelcoat.eu