In vitro investigations on retention force behavior of conventional and modern double crown systems.

Viktor Luft, Peter Pospiech, Axel Schurig, Marc Schmitter

Dental materials : official publication of the Academy of Dental Materials 2021 Jan

filter terms:

This study aimed to investigate the effects of long-term use on the retention force and wear behavior of double crown systems. Based on a common double crown design sixty pairs of telescopic crowns were fabricated and divided into six groups, each consisting ten samples: "Gold standard" cast gold alloy primary and secondary crown (GG) and cast non-precious alloy (NN), computer-aided design (CAD)/computer-aided manufacturing (CAM)-milled zirconia primary crown and galvanoformed secondary crown (ZG), CAD/CAM-milled non-precious alloy primary and secondary crown (CC NN), CAD/CAM-milled zirconia primary crown and non-precious alloy secondary crown (CC ZN) and CAD/CAM-milled zirconia primary crown and polyetheretherketone (PEEK) secondary crown (CC ZP). In the constant presence of artificial saliva, all samples were subjected to 10,000 joining-separation cycles at a velocity of 120 mm/min. Wear was analyzed by reflected light microscopy and confocal microscopy before and after artificial aging. Retention force losses were observed in each group after long-term use, with significant losses in the groups ZG and CC ZP (pZG = 0.01, pCC ZP = 0.049). During artificial aging, no significant differences in pull-off force were recorded for groups GG, NN and CC ZN. Regarding wear, merely the Y-TZP primary crowns of the CC ZP group displayed no surface changes. All tested production methods and material combinations seem to be suitable for clinical practice. CAD/CAM technology allows similarly predictable results to be achieved as the gold standard. Confocal microscopy is recommended for surface examinations of double crowns. Copyright © 2020 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved.

Citation

Viktor Luft, Peter Pospiech, Axel Schurig, Marc Schmitter. In vitro investigations on retention force behavior of conventional and modern double crown systems. Dental materials : official publication of the Academy of Dental Materials. 2021 Jan;37(1):191-200