Investigation of Mechanical Properties of Denture Base Materials Using PEEK

Objectives: Aim of this study was to investigate mechanical properties of denture base materials using PEEK.
Methods: PEEK (VEATAKEEP, Daicel Evonik), a polyester injection-molded thermoplastic resin (EstheShot Bright, i-Cast Co. Ltd.) and two conventional PMMA (Palapress Vario, Heraeus Kulzer and Acron GC Corp.) were selected for this study. Processing methods were PEEK and EstheShot Bright were using Injection molding technique, Palapress Vario was pour polymer system and Acron was heat-polymerized, compression molding technique. The three-point bending test specimens were fabricated according to the ISO 20795-1 (65x10x3.3mm). The impact strength test was applied a Charpy impact strength test (size 50x6x4mm). All of the specimens were immersed in distilled water at 37 degrees for 48±2 h before testing. The flexural strength at the proportional limit (MPa), the elastic modulus (GPa) and the impact strength (kJ/m²) were measured. Statistical analysis were carried with ANOVA and Newman-Keuls post hoc test.
Results: Summary of results are shown in the table below:
Same superscript letter shows no statistical differences (p<0.05).

The descending order of the flexural strength at the proportional limit was: PEEK > Palapress Vario = Acron > EstheShot Bright. The descending order of elastic modulus was: PEEK > Acron > Palapress Vario >EstheShot Bright. The descending order of the impact strength was: EstheShot Bright > PEEK > Palapress Vario = Acron.
Conclusions: The results of this study suggest that, PEEK could be consider a denture base resin due to have higher flexural properties than PMMA and a polyester injection-molded thermoplastic resin and higher the impact strength than PMMA.