Comparison of fit of poly (etheretherketone) and cobalt-chromium removable partial denture frames: an in-vitro study.


  • Ary Yaqoub Putros Department of Prosthodontics, College of Dentistry, Hawler Medical University, Erbil, Iraq.
  • Jawad Mohammed Mikaeel Department of Prosthodontics, College of Dentistry, Hawler Medical University, Erbil, Iraq.



fit accuracy, laboratory research, removable partial denture framework


Background and objective: the adaptation of the Removable partial denture (RPD) is a key factor in the success of the treatment outcome. This study aims to compare the fit of Poly(etheretherketone)(PEEK) and cobalt-chromium (Co-Cr) frames through the rest seat adaptation

Methods: Ideal typodont model of the maxillary partially edentulous case (Kennedy Class III), four rest seats were prepared on abutment teeth afterwards, and the cast was turned into a metal master cast to serve as a reference cast. Twenty RPD samples were made, ten samples for the Co-Cr group and ten for the PEEK group. A Vinyl Polysiloxane(VPS) is used to paint the intaglio surface of the rest, and the frame samples are held in place with finger pressure on the master cast. Eighty VPS samples were made to present the gap between rest and rest seats; these samples were measured using a digital micrometre under a microscope with a magnification of 40x. The data were analysed using SPSS programs with an independent T-test.

Results: comparison between the two groups revealed that the PEEK groups had a better fit in one tooth #17 with a mean of (147.2 µm) than the Co-Cr group (252.6 µm), which is statically significant with a P value of (0.000). The other three abutments showed no significant difference.

Conclusion: RPD frames made from PEEK showed a slightly better fit than Co-Cr frames.



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How to Cite

Putros AY, Mikaeel JM. Comparison of fit of poly (etheretherketone) and cobalt-chromium removable partial denture frames: an in-vitro study. EDJ [Internet]. 2023 Jun. 30 [cited 2023 Sep. 27];6(1):113-9. Available from:



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