Retentive force of PEEK secondary crowns on zirconia primary crowns over time

  • Oliver SchubertEmail author
  • Josef Reitmaier
  • Josef Schweiger
  • Kurt Erdelt
  • Jan-Frederik Güth
Original Article



The purpose of the present study was to evaluate the retentive forces of CAD/CAM-fabricated polyetheretherketone (PEEK) secondary crowns on zirconia primary crowns over an artificial aging period representing 10 years of clinical service and compare them to electroformed secondary crowns made from pure gold.

Material and methods

Implant-supported zirconia primary crowns (N = 20) were CAD/CAM milled and provided either with electroformed secondary crowns (group ZE; N = 10) or CAD/CAM-fabricated PEEK secondary crowns (group ZP; N = 10). All secondary crowns were attached to a casted tertiary structure to ensure adequate stability. A universal testing machine was used to determine the retentive force values at baseline and after 1, 3, 5, and 10 years of simulated aging in the presence of artificial saliva. Data were analyzed applying Kolmogorov-Smirnov, Kruskal-Wallis, and Mann-Whitney U test. Level of significance was set at p < 0.05.


Retentive forces were not different for the groups ZE and ZP at baseline (median ZE 2.85 N; ZP 2.8 N; p ≤ 0.218). Because retentive force values changed significantly over simulation time for group ZE (Kruskal-Wallis; p ≤ 0.028), the values between the test groups ZE and ZP differed significantly (Mann-Whitney U) at 5 years (ZE 3.03 N; ZP 2.76 N; p ≤ 0.003) and 10 years (ZE 3.1 N; ZP 2.78 N; p ≤ 0.011).


PEEK secondary crowns exhibit stable retentive force values over 10 years of simulated aging showing no signs of deterioration while the retentive force values of electroformed secondary crowns increase over time.

Clinical relevance

PEEK might be a suitable alternative to proven metallic materials for the fabrication of secondary crowns.


CAD/CAM Double crowns Electroforming Polyetheretherketone (PEEK) Retentive force Implant prosthetics Zirconia 



The authors thank Zirkonzahn (Gais, Italy) for supporting this investigation.


The work was financially supported by Zirkonzahn, Gais, Italy.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.

Informed consent

For this type of study, formal consent is not required.


  1. 1.
    van Noort R (2012) The future of dental devices is digital. Dent Mater 28(1):3–12. CrossRefPubMedGoogle Scholar
  2. 2.
    Starr W (1886) Removable bridge-work. - porcelain cap-crowns. The Dental cosmos; a monthly record of dental science 28 (1):17–19Google Scholar
  3. 3.
    Langer A (1981) Telescope retainers for removable partial dentures. J Prosthet Dent 45(1):37–43CrossRefGoogle Scholar
  4. 4.
    Lian M, Zhao K, Feng Y, Yao Q (2018) Prognosis of combining remaining teeth and implants in double-crown-retained removable dental prostheses: a systematic review and meta-analysis. Int J Oral Maxillofac Implants 33(2):281–297. CrossRefPubMedGoogle Scholar
  5. 5.
    Rammelsberg P, Bernhart G, Lorenzo Bermejo J, Schmitter M, Schwarz S (2014) Prognosis of implants and abutment teeth under combined tooth-implant-supported and solely implant-supported double-crown-retained removable dental prostheses. Clin Oral Implants Res 25(7):813–818. CrossRefPubMedGoogle Scholar
  6. 6.
    Langer Y, Langer A (2000) Tooth-supported telescopic prostheses in compromised dentitions: a clinical report. J Prosthet Dent 84(2):129–132. CrossRefPubMedGoogle Scholar
  7. 7.
    Böttger H (1953) Die prothetische Versorgung des Lü̧ckengebisses mit Teleskopprothesen. Zahnärztl Rundsch (62):18–23Google Scholar
  8. 8.
    Hofmann M (1966) Die Versorgung von Gebissen mit einzelstehenden Restzähnen mittels sog. Cover-Denture-Prothesen. Dtsch Zahnärztl Z 21:478–482Google Scholar
  9. 9.
    Körber K (1968) Konuskronen – ein physikalisch definiertes Teleskopsystem. Dtsch Zahnärztl Z 23:619–630PubMedGoogle Scholar
  10. 10.
    Koller B, Att W, Strub JR (2011) Survival rates of teeth, implants, and double crown-retained removable dental prostheses: a systematic literature review. Int J Prosthodont 24(2):109–117PubMedGoogle Scholar
  11. 11.
    Wostmann B, Balkenhol M, Kothe A, Ferger P (2008) Dental impact on daily living of telescopic crown-retained partial dentures. Int J Prosthodont 21(5):419–421PubMedGoogle Scholar
  12. 12.
    Stober T, Danner D, Bomicke W, Hassel AJ (2016) Improvement of oral health-related quality-of-life by use of different kinds of double-crown-retained removable partial dentures. Acta Odontol Scand 74(1):1–6. CrossRefPubMedGoogle Scholar
  13. 13.
    Langer A (1980) Telescope retainers and their clinical application. J Prosthet Dent 44(5):516–522 doi:0022-3913(80)90070-0CrossRefGoogle Scholar
  14. 14.
    Arnold C, Hey J, Setz JM, Boeckler AF, Schweyen R (2017) Retention force of removable partial dentures with different double crowns. Clin Oral Investig 22:1641–1649. CrossRefPubMedGoogle Scholar
  15. 15.
    Diedrichs G, Rosenhain P (1991) Galvano-Außenteleskope in der direkten Technik. Quintessenz 42:49–55PubMedGoogle Scholar
  16. 16.
    Vence BS (1997) Electroforming technology for galvanoceramic restorations. J Prosthet Dent 77(4):444–449CrossRefGoogle Scholar
  17. 17.
    Weigl P, Hahn L, Lauer HC (2000) Advanced biomaterials used for a new telescopic retainer for removable dentures. J Biomed Mater Res 53(4):320–336CrossRefGoogle Scholar
  18. 18.
    Weigl P, Lauer HC (2000) Advanced biomaterials used for a new telescopic retainer for removable dentures. J Biomed Mater Res 53(4):337–347CrossRefGoogle Scholar
  19. 19.
    Bayer S, Kraus D, Keilig L, Golz L, Stark H, Enkling N (2012) Wear of double crown systems: electroplated vs. casted female part. J Appl Oral Sci 20(3):384–391CrossRefGoogle Scholar
  20. 20.
    Beuer F, Edelhoff D, Gernet W, Naumann M (2010) Parameters affecting retentive force of electroformed double-crown systems. Clin Oral Investig 14(2):129–135. CrossRefPubMedGoogle Scholar
  21. 21.
    Faber F, Huber C (2001) Electroformed telescope crowns – a hydraulic system. J Dent Res 80(Spec Iss):551Google Scholar
  22. 22.
    Schwindling FS, Lehmann F, Terebesi S, Corcodel N, Zenthofer A, Rammelsberg P, Stober T (2017) Electroplated telescopic retainers with zirconia primary crowns: 3-year results from a randomized clinical trial. Clin Oral Investig 21(9):2653–2660. CrossRefPubMedGoogle Scholar
  23. 23.
    Schwindling FS, Stober T, Rustemeier R, Schmitter M, Rues S (2016) Retention behavior of double-crown attachments with zirconia primary and secondary crowns. Dent Mater 32(5):695–702. CrossRefPubMedGoogle Scholar
  24. 24.
    Bayer S, Kraus D, Keilig L, Golz L, Stark H, Enkling N (2012) Changes in retention force with electroplated copings on conical crowns: a comparison of gold and zirconia primary crowns. Int J Oral Maxillofac Implants 27(3):577–585PubMedGoogle Scholar
  25. 25.
    Engels J, Schubert O, Guth JF, Hoffmann M, Jauernig C, Erdelt K, Stimmelmayr M, Beuer F (2013) Wear behavior of different double-crown systems. Clin Oral Investig 17(2):503–510. CrossRefPubMedGoogle Scholar
  26. 26.
    Miyazaki T, Nakamura T, Matsumura H, Ban S, Kobayashi T (2013) Current status of zirconia restoration. J Prosthodont Res 57(4):236–261. CrossRefPubMedGoogle Scholar
  27. 27.
    Miyazaki T, Hotta Y, Kunii J, Kuriyama S, Tamaki Y (2009) A review of dental CAD/CAM: current status and future perspectives from 20 years of experience. Dent Mater J 28:44–56CrossRefGoogle Scholar
  28. 28.
    Kurtz SM, Devine JN (2007) PEEK biomaterials in trauma, orthopedic, and spinal implants. Biomaterials 28(32):4845–4869. CrossRefPubMedPubMedCentralGoogle Scholar
  29. 29.
    Skinner HB (1988) Composite technology for total hip arthroplasty. Clin Orthop Relat Res (235):224-236Google Scholar
  30. 30.
    Najeeb S, Bds ZK, Bds SZ, Bds MS (2016) Bioactivity and osseointegration of PEEK are inferior to those of titanium: a systematic review. J Oral Omplantol 42(6):512–516. CrossRefGoogle Scholar
  31. 31.
    Hahnel S, Wieser A, Lang R, Rosentritt M (2015) Biofilm formation on the surface of modern implant abutment materials. Clin Oral Implants Res 26(11):1297–1301. CrossRefPubMedGoogle Scholar
  32. 32.
    Wimmer T, Huffmann AM, Eichberger M, Schmidlin PR, Stawarczyk B (2016) Two-body wear rate of PEEK, CAD/CAM resin composite and PMMA: effect of specimen geometries, antagonist materials and test set-up configuration. Dent Mater 32(6):e127–e136. CrossRefPubMedGoogle Scholar
  33. 33.
    Najeeb S, Zafar MS, Khurshid Z, Siddiqui F (2016) Applications of polyetheretherketone (PEEK) in oral implantology and prosthodontics. J Prosthodont Res 60(1):12–19. CrossRefPubMedGoogle Scholar
  34. 34.
    Stock V, Schmidlin PR, Merk S, Wagner C, Roos M, Eichberger M, Stawarczyk B (2016) PEEK primary crowns with cobalt-chromium, zirconia and galvanic secondary crowns with different tapers-a comparison of retention forces. Materials (Basel) 9(3). CrossRefGoogle Scholar
  35. 35.
    Wagner C, Stock V, Merk S, Schmidlin PR, Roos M, Eichberger M, stawarczyk B (2018) Retention load of telescopic crowns with different taper angles between cobalt-chromium and polyetheretherketone made with three different manufacturing processes examined by pull-off test. J Prosthodont 27(2):162–168CrossRefGoogle Scholar
  36. 36.
    Merk S, Wagner C, Stock V, Eichberger M, Schmidlin PR, Roos M, Stawarczyk B (2016) Suitability of secondary PEEK telescopic crowns on zirconia primary crowns: the influence of fabrication method and taper. Materials (Basel) 9(11). CrossRefGoogle Scholar
  37. 37.
    Stock V, Wagner C, Merk S, Roos M, Schmidlin PR, Eichberger M, Stawarczyk B (2016) Retention force of differently fabricated telescopic PEEK crowns with different tapers. Dent Mater J 35(4):594–600. CrossRefPubMedGoogle Scholar
  38. 38.
    Ohkawa S, Okane H, Nagasawa T, Tsuru H (1990) Changes in retention of various telescope crown assemblies over long-term use. J Prosthet Dent 64(2):153–158CrossRefGoogle Scholar
  39. 39.
    Gungor MA, Artunc C, Sonugelen M (2004) Parameters affecting retentive force of conus crowns. J Oral Rehabil 31(3):271–277. CrossRefPubMedGoogle Scholar
  40. 40.
    Hatton MN, Levine MJ, Margarone JE, Aguirre A (1987) Lubrication and viscosity features of human saliva and commercially available saliva substitutes. J Oral Maxillofac Surg 45(6):496–499CrossRefGoogle Scholar
  41. 41.
    Dillschneider T, Nothdurft F, Abed-Rabbo M, Mitov G, Pospiech P (2009) In vitro-investigations on the wear behavior of different double crown systems. Dent Mater 25(5):e20CrossRefGoogle Scholar
  42. 42.
    Becker H (1982) Untersuchung der Abzugskräfte abnehmbarer Teleskop-Prothesen. Zahnärztl Prax 33:153–156PubMedGoogle Scholar
  43. 43.
    Hahnel S, Scherl C, Rosentritt M (2018) Interim rehabilitation of occlusal vertical dimension using a double-crown-retained removable dental prosthesis with polyetheretherketone framework. J Prosthet Dent 119(3):315–318. CrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Prosthetic DentistryUniversity Hospital, LMU MunichMunichGermany
  2. 2.Dental Team GmbHBergenGermany

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