Maple Coating of Zirconia with Peg-pcl Embedded Cyprinol for Ear Implant Applications

Hearing accompanies us everywhere and it is our relationship with the environment. Without it we cannot understand the beauty of music, the voice vibrations of loved ones and especially the dangers which lurk us everywhere in this industrialized world. For the deaf people hearing aid represents their best friend and hearing implants that become part of their own body, even more. Since 1952, when an orthopaedic surgeon, Per-Ingvar Brånemark, discovered the miraculous properties of titanium to osseointegrate, this material had been used for dental implants, orthopedic prostheses and Bone Anchored Hearing Aid (BAHA) implants. As opposed to titanium, zirconium oxide (Zirconia, ZrO2) is a ceramic material from hightech category, highly resistant, with a multitude of applications, in industry (cutting tools, brakes of sport cars and aircraft components, anti-overhead shields for cosmic ships, fuel cells), medicine and even as a substitute for diamond jewellery. Our work investigates the potential of Zirconia and polymer coated Zirconia to osseointegrate and its biocompatibility with human bone tissue. For this, we coated Zirconia substrates with poly(ethylene glycol)-poly(caprolactone) (PEG-PCL) biodegradable copolymer by using a laser based technique – Matrix Assisted Pulsed Laser Deposition (MAPLE). To prevent potential bacterial infections that may occur during surgery, we propose the introduction of cyprinol into this scaffold. We investigated the interaction of the designed biomaterials with human SaOs2 osteosarcoma cells which were cultivated onto their surface. Inverted microscope images showed that Zirconia coated or not with polymer layers and/or antibiotic do not produce cytotoxic effects. Assessment of cell adhesion showed that MAPLEdeposited films support cell attachment and growth. Actin filaments are stretched and cross the cytoplasm, with the evidence of smaller and less spread cells, with many short actin bundles in the case of copolymer films. This study will help to expand the use of Zirconia for BAHA implants.