Impact of material combinations and removal and insertion cycles on the retention force of telescopic systems

Danka Micovic Soldatovic; Maximiliane Bitter; John Meinen; Karin Christine Huth; Anja Liebermann; Bogna Stawarczyk

doi:10.1007/s00784-023-05027-w

Impact of material combinations and removal and insertion cycles on the retention force of telescopic systems

Clin Oral Investig. 2023 Jul;27(7):4007-4016. doi: 10.1007/s00784-023-05027-w. Epub 2023 Apr 22.

Authors

Danka Micovic Soldatovic¹, Maximiliane Bitter², John Meinen², Karin Christine Huth³, Anja Liebermann⁴, Bogna Stawarczyk²

Affiliations

¹ Department of Prosthetic Dentistry, University Hospital, LMU Munich, Goethestrasse 70, 80336, Munich, Germany. danka.micovic@med.uni-muenchen.de.
² Department of Prosthetic Dentistry, University Hospital, LMU Munich, Goethestrasse 70, 80336, Munich, Germany.
³ Department of Conservative Dentistry and Periodontology, University Hospital, LMU Munich, Goethestrasse 70, 80336, Munich, Germany.
⁴ Polyclinic of Prosthetic Dentistry, Faculty of Medicine and University Hospital Cologne, University of Cologne, Kerpener Strasse 32, 50931, Cologne, Germany.

Abstract

Objectives: A variety of dental materials are available for the fabrication of telescopic crowns. The aim was to investigate the impact of material combinations and removal and insertion cycles on their retention forces.

Materials and methods: CAD/CAM-fabricated cobalt-chromium-molybdenum (CoCr) and zirconia (ZrO₂) primary crowns were combined with polyetheretherketone (PEEK), polyetherketoneketone (PEKK), CoCr, and ZrO₂ secondary crowns (four combinations included PEEK/PEKK secondary crowns in a thickness of 0.5 mm bonded to the CoCr tertiary construction), resulting in 12 different material combinations: CoCr-PEEK; CoCr-PEKK; CoCr-ZrO₂; CoCr-CoCr; CoCr-PEEK 0.5; CoCr-PEKK 0.5; ZrO₂-PEEK; ZrO₂-PEKK; ZrO₂-ZrO₂, ZrO₂-CoCr; ZrO₂-PEEK 0.5; and ZrO₂-PEKK 0.5 (n = 15 pairings per material combination). Pull-off tests were performed with a universal testing machine initially and after 500, 5000, and 10,000 removal and insertion cycles in a mastication simulator. Descriptive statistics with the Kolmogorov-Smirnov, Kruskal-Wallis, and Mann-Whitney U tests were computed (α = 0.05).

Results: The tested parameters, material combination, and removal and insertion cycles had significant impact on the retention force values (p < 0.001). An increase in removal and insertion cycles was associated with a decrease in retention forces within CoCr and ZrO₂ secondary crowns, regardless of the primary crown material. In contrast, PEEK and PEKK secondary crowns presented higher retention load values after 10,000 cycles than initially.

Conclusion: Different material combinations behaved differently after simulated removal and insertion regimens. This difference should be considered during treatment planning.

Clinical relevance: Telescopic crown systems should be made of materials with predictable retention forces that do not deteriorate with time. The implementation of new materials and technologies facilitates reproducibility and time-saving fabrication.

Keywords: Artificial aging; Double-crown system; PEEK; PEKK; Retention force measurements; Zirconia.

MeSH terms

Benzophenones*
Crowns
Dental Stress Analysis
Ketones
Materials Testing
Polyethylene Glycols
Polymers*
Reproducibility of Results

Substances

polyetheretherketone
polyetherketoneketone
Polymers
Benzophenones
Polyethylene Glycols
Ketones