Polymer Biomaterials for Orthopedic and Dental Implants

Polymeric biomaterials have emerged as versatile alternatives to traditional metallic implants in both orthopaedic and dental applications. Materials such as polyetheretherketone (PEEK) and its derivatives offer mechanical properties closer to that of human bone, reducing stress shielding and promoting more uniform load transfer. Their chemical stability, radiolucency and resistance to corrosion are complemented by lower weight and the potential for patient-specific design via additive manufacturing. However, the inherent biological inertness of many high-performance polymers necessitates surface or composite modifications to enhance bioactivity and osseointegration. Recent advances encompass nano-scaled coatings, incorporation of bioactive fillers and ambient-temperature chemical treatments, all aimed at improving cellular adhesion, proliferation and long-term implant stability. These developments hold promise for longer-lasting, better-integrated implants in diverse clinical settings.

Research from Nature Portfolio

Recent finite element analyses have focussed on removable partial denture frameworks manufactured from PEEK. Computational models simulating masticatory loads reveal that PEEK frameworks exert lower stress on periodontal ligaments than conventional cobalt-chromium or titanium designs, suggesting protective effects for compromised dentitions. However, increased displacement at free-end saddles and higher mucosal stresses indicate that PEEK may require additional support or hybrid designs in cases of extensive posterior edentulism. These insights into stress distribution and deformation under functional load provide a quantitative basis for optimising framework geometry and selecting polymer-metal combinations for individual patient needs.

Polymer Biomaterials for Orthopedic and Dental Implants publication trend

The graph below shows the total number of articles in polymer biomaterials for orthopedic and dental implants across all publications each year (not limited to Nature Index journals).

Technical terms

Polyetheretherketone (PEEK): A high-performance thermoplastic polymer with mechanical properties similar to cortical bone, used as a biomaterial for implants.

Osseointegration: The direct structural and functional connection between living bone and the surface of an implant.

Elastic modulus: A measure of a material’s stiffness, defined as stress divided by strain in the elastic deformation region.

Hydroxyapatite (HA): A calcium phosphate ceramic that mimics the mineral phase of bone and promotes bone ingrowth when incorporated into composites or coatings.

Finite element analysis (FEA): A computational technique that divides a complex structure into discrete elements to predict stress, strain and deformation under applied loads.

References

1. Poly-Ether-Ether-Ketone (PEEK) Biomaterials and Composites: Challenges, Progress, and Opportunities. Polymer Reviews (2024).
2. A three-dimensional finite element analysis of mechanical function for 4 removable partial denture designs with 3 framework materials: CoCr, Ti-6Al-4V alloy and PEEK. Scientific Reports (2019).
3. Evaluating the bioactivity of a hydroxyapatite-incorporated polyetheretherketone biocomposite. Journal of Orthopaedic Surgery and Research (2019).
4. PEEK surface modification by fast ambient-temperature sulfonation for bone implant applications. Journal of The Royal Society Interface (2019).