Evaluation of the mechanical properties and fit of 3D-printed polyetheretherketone removable partial dentures

Abstract

Compared with CAD/CAM, fused deposition modeling (FDM) 3D printing technology is simple and safe to operate and has a low cost and high material utilization rate; thus, it is widely used. The present investigation aimed to evaluate the mechanical properties and fit of polyetheretherketone (PEEK) removable partial dentures (RPDs) constructed by FDM. We analyzed mechanical properties of PEEK samples prepared by FDM, milling, or injection molding. RPDs were designed and finite element analysis models was constructed to evaluate maximum stress and strain in the RPDs, cortical bone and mucosa. Geomagic Qualify software was used to analyze gaps between the model and the tissue surface of the framework. The results showed that the compressive strength of the 3D-printed PRDs was greater than that of the injection-molded samples. Finite element analysis demonstrated that the maximum stress on the PRDs was less than the yield strength of the material. Overall, the mechanical properties and fit of the PEEK RPD fabricated by FDM technology essentially fulfilled clinical requirements.

Mechanical Properties of Fused Deposition Modeling of Polyetheretherketone (PEEK) and Interest for Dental Restorations: A Systematic Review

“…Several parameters influence the printing of PEEK via FDM technology and, thus, its mechanical properties: the layer thickness [ 21 , 22 , 23 , 24 , 25 , 26 ], the nozzle diameter [ 27 ], the printing speed [ 23 , 27 ], the printing temperature [ 22 , 23 , 24 , 27 , 28 , 29 ], the chamber temperature [ 28 , 30 , 31 ], the raster angle [ 21 , 24 , 25 , 26 , 32 , 33 ], the build plate orientation [ 16 , 24 , 34 , 35 ], the infill rate [ 35 ], the PEEK modifications [ 34 , 36 , 37 ] and the possible post-treatment [ 25 , 31 , 36 , 38 ].…”

“…Among the 18 studies included, 4 exhibited a low risk of bias [ 35 , 39 , 40 , 41 ], 14 showed a moderate risk [ 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 33 , 34 , 35 ] and none exhibited a high risk of bias ( Table 2 , Figure 2 ). Studies were badly scored in relation to the blinding of the tests and the calculation of sample size or allocation, whereas all studies [ 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 36 , 37 , 38 ] except one [ 35 ] were found to be adequate in regard to the presence of a control group.…”

“…After 2 h of heat post-treatment at 300 °C, the compressive strength of the FDM 3D-printed PEEK elements was comparable to that of milled elements and 20% higher than that of injection-molded PEEK elements [ 38 ]. There were no significant differences in tensile properties and the flexural strength of FDM 3D-printed PEEK elements was 11% lower than that of the milled elements.…”

“…There were no significant differences in tensile properties and the flexural strength of FDM 3D-printed PEEK elements was 11% lower than that of the milled elements. The posttreatment increased the toughness of the 3D PEEK elements, which was higher than that of the milled and molded PEEK elements [ 38 ].…”

Clinical Applications of Polyetheretherketone in Removable Dental Prostheses: Accuracy, Characteristics, and Performance

“…The suitability and accuracy of removable prostheses are important and key points that can be used to evaluate their clinical performance. Good suitability facilitates maximum support, retention, and stability in removable prostheses [ 11 ], and it helps avoid adverse mechanical stimulation and the negative effects caused by biological factors during masticatory force [ 12 ]. An inadequate fit may accelerate abutment movement and lower masticatory efficiency, with poor retention being the chief problem during functional movement [ 13 ].…”