Present and Theoretical Applications of Poly-Ether-Ether-Ketone (PEEK) in Orthodontics: A Scoping Review

Abstract

Background: During the last decade, there has been an increased demand for non-metallic materials in orthodontics due to allergies, compatibility with medical imaging devices such as MRI, and aesthetic reasons. Monolithic poly-ether-ether-ketone material could address medical issues such as allergies and MRI compatibility. Moreover, nickel–titanium (NiTi) archwires covered in PEEK, either by a tube or electrophoretic deposition, could address esthetic concerns. This scoping review aims to summarize the available evidence in the literature to provide an overview of the applications and material properties of PEEK in orthodontics. Methods: This scoping review was conducted according to the Joanna Briggs Institute Manual for Evidence Synthesis for scoping reviews and the Preferred Reporting Items for Systematic Review and Meta-Analyses Protocols extension for Scoping Reviews (PRISMA-ScR). We searched for relevant publications in MEDLINE (via PubMed), Embase, Web of Science, Cochrane Library, CENTRAL, ProQuest, and SCOPUS. A gray literature search was conducted on Google Scholar. Results: Six studies were included. In three studies, the authors investigated the feasibility of developing a composite PEEK-NiTi wire, while in two other studies, the authors investigated the feasibility of monolithic PEEK wires. In the final study, the authors investigated the feasibility of PEEK as a bonded retainer. Conclusions: The included studies show promising results in developing monolithic and composite (PEEK-NiTi) materials. Further research on the robustness of PEEK composites in the oral cavity, the status of cytotoxicity and roughness values, and the (bio)-mechanical behavior of the composites is needed. A homogenously set up comparative study of clinically relevant, evenly sized, monolithic PEEK wires versus conventional orthodontic wires for their biomechanical, mechanical, and material properties would clarify the possibilities of developing monolithic PEEK wires. Missing data in the retainer study suggest more research on the mechanical properties and points of failure of PEEK-bonded retainers, and a comparative study comparing the failure and mechanical properties of PEEK-bonded retainers to flat braided metallic bonded retainers is needed.

Direct 3D-Printed Orthodontic Retainers. A Systematic Review

“…It is already known for its application in dentistry for implants or prosthetic restorations, but it also seems to be a promising material for orthodontic purposes due to its superior physical, mechanical and aesthetic properties, biocompatibility, low plaque affinity and flexural modulus close to enamel and dentin. However, more clinical research is necessary [ 31 , 79 ]. A case report also referred to an experimental resin (Genial Printing Resin, GC) from GC Orthodontics (GC America Inc., Alsip, IL, USA) for 3D printing of fixed retention [ 28 ].…”

“…PEEK material (poly-ether-ether-ketone) seems promising due to its biocompatibility, which could address issues such as allergies and MRI artifacts or nickel–titanium (NiTi) archwires covered in PEEK could also address esthetic concerns. However, more research is necessary to investigate other aspects such as the mechanical properties or the cytotoxicity of this polymer [ 31 ].…”

PEEK for Oral Applications: Recent Advances in Mechanical and Adhesive Properties

“…In a self-ligating system, PEEK has comparable mechanical properties in load deflection to that of Ni-Ti wires [ 128 ]. Additionally, orthodontic wires covered with a PEEK tube can reduce friction, demonstrating a good combination of aesthetic and functional properties [ 129 ]. When used in a retainer following orthodontic treatment, PEEK can also provide a comparable performance to conventional retainers in terms of debonding and pull-out forces [ 130 ].…”

“…When used in a retainer following orthodontic treatment, PEEK can also provide a comparable performance to conventional retainers in terms of debonding and pull-out forces [ 130 ]. However, more research is needed on the mechanical properties and failure points of PEEK-bonded retainers [ 129 ].…”

Graphene loaded into dental polymers as reinforcement of mechanical properties: A systematic review

“… [26] The PEEK family polyaryletherketone (PAEK), presents advantages over the polymers already studied, with future perspectives to improve the quality and satisfaction of dental treatments for being stable at low temperatures and above 300 °C, which makes it resistant to structural damage. [27] It was first applied in dentistry to make implants, [28] due to its high resistance to fatigue, wear and ability to withstand mechanical stress and is currently used for fixed partial dentures [29] and removable partial dentures, from the making of clasp [30] to infrastructure. [31] The material is also color-characterizable, which favors clinical esthetics.…”