One of the challenges faced by modern dentistry is improving the biomechanics and biocompatibility of materials used for implant therapy. Metals, ceramics, and polymers stand out in the materials used to manufacture the superstructures and different attachments of dental implants. Recently, there has been a huge demand for non-metallic materials for oral environments due to their corrosion and ion release issues. Polymers are materials made up of macromolecules; they are composed of smaller molecules, monomers, which can form linear or racemic chains. According to this relationship, they will have certain properties or other properties.
Generally, compared to other types of biomaterials, polymers have a lower elastic modulus and greater elongation at break. Most polymers have a lower elastic modulus compared to bone, with an amplitude approaching that of soft tissue. When used in the form of high molecular weight, they are thermal and electrical insulators, contain no plasticizers, and are relatively biodegradable.
Among the most inert polymer biomaterials, noteworthy are polytetrafluoroethylene (PTFE), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), polyether ether ketone (PEEK), and ceramic-filled polyether ether ketone (BioHPP).
Polyetheretherketone is a partially crystalline polymer widely used in the industrial sector and gradually introduced into the biomedical field. It was patented as an implant material in 1981 and accepted by the FDA (Food and Drug Administration) in 1990, especially in the fields of orthopedics, traumatology, and neurosurgery.
In 1988, PEEK polymer material was approved for oral dental applications, and in 2011, it began to be used in the field of dental implantology. It was initially used very effectively for temporary and permanent implant abutments and healing screws. However, it is now increasingly used to cover dentures and hybrid dentures, as well as screw-fixed bridges in implant prostheses. Its versatility, biocompatibility, and biomechanical characteristics make this material a promising alternative to dental alloys.
Among all the characteristics of polyetheretherketone, its advantage for use in implant prostheses is its low elastic modulus, similar to that of bone, with a low hardness that does not cause wear on teeth. Compared to ceramics, its good polishing can reduce bacterial plaque adhesion. Lastly, its good adhesion to coating materials ensures better resistance to detachment or fracture. On the other hand, it has some inconvenient characteristics, such as the possibility of deformation under stress and a certain solubility and water absorption of coating resins in water and humid environments such as the oral cavity.