Purpose: Resinous cements are widely used for luting zirconia restorations. Adhesive failures have occurred at the cement/zirconia interface, rather than at the cement/dentin interface, suggesting that the cement/zirconia bond may lack durability; however, few comprehensive, comparative evaluations of fatigue effects have been reported. The rate of fatigue-induced loss of bond strength may be a more important predictor of long-term success than a single snapshot of bond strength after an arbitrary number of thermocycles. Previous studies have failed to identify trends by investigating bond strengths at several different numbers of cycles. This may result in invalid conclusions about which cements have superior bond strengths. The purpose of this study was to investigate the effects of artificial aging by thermocycling and resinous cement type on bond strengths to zirconia.
Materials And Methods: The effect of the number of thermocycles (0, 1, 10, 100, 1000, and 10,000) on the bond strengths of five resinous cements, two of which were used with and without a primer, and an oxygen-inhibiting gel, was studied. Specimens were randomly assigned to thermocycle number/cement-type test groups. Because zirconia has a very low thermal diffusivity, exceptionally long thermocycle dwell times were used. Cylinders of zirconia were bonded end-to-end. One end of each bonded specimen was insulated, specimens were thermocycled and tested in shear, and bond strengths were calculated and analyzed.
Results: Two-way ANOVA revealed that the effects of cement type, the number of thermocycles, and their interaction all significantly affected bond strength (p < 0.0001). By 10,000 cycles, most cements had lost at least half of their initial bond strengths, and two cements effectively recorded zero bond strengths. Failure modes were cement specific, but adhesive modes predominated. Fatigue resistance of two cements was greatly improved by use of a primer and an oxygen-inhibiting gel, as recommended by their respective manufacturers.
Conclusions: Both the type of resin cement and the number of thermocycles influenced bond strength. Fatigue through thermocycling affected different cement types in different ways. Some materials displayed more rapid loss of bond strength than others. Cements differed in their failure modes.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1111/jopr.12053 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Weakening Pd─O Bonds by an Amorphous Pd Layer to Promote Electrocatalysis.
Small
January 2025
Institute of Materials for Energy and Environment, College of Materials Science and Engineering, Qingdao University, Qingdao, 266071, P. R. China.
Construction of core-shell structured electrocatalysts with a thin noble metal shell is an effective strategy for lowering the usage of the noble metal and improving electrocatalytic properties because of the structure-induced geometric and electronic effects. Here, the synthesis of a novel core-shell structured nanocatalyst consisting of a thin amorphous Pd shell and a crystalline PdCu core and its significantly improved electrocatalytic properties for both formic acid oxidation and oxygen reduction reactions are shown. The electrocatalyst exhibits 4.
View Article and Find Full Text PDFEffect of Chemical Treatment on the Mechanical and Hygroscopic Properties of an Innovative Clay-Sand Composite Reinforced with Fibers.
Materials (Basel)
January 2025
Laboratoire d'Energétique et des Transferts Thermique et Massique (LETTM), Faculté des Sciences de Tunis, Université de Tunis El Manar, Campus Universitaire El-Manar, El Manar, Tunis 2092, Tunisia.
The viability of using fibers as reinforcement material for developing lightweight sustainable non-structural construction materials in compliance with the valorization of local by-products has been investigated in this work. This study aims to investigate the effect of the chemical treatment of fibers on the mechanical and hygric properties of bio-sourced clay-sand- fiber composite. This lightweight specimen has been produced from a mixture of 60% natural clay and 40% sand by mass, as a matrix, and reinforced with different amounts of Juncus fibers.
View Article and Find Full Text PDFEffects of Moisture Infiltration on Interfacial Characteristics of Fiber Asphalt Mastic-Aggregate and the Cracking Resistance of Mixture.
Materials (Basel)
December 2024
College of Civil Science and Engineering, Yangzhou University, Yangzhou 225100, China.
The interfacial properties of fiber asphalt aggregate and the cracking resistance of asphalt mixture are directly affected by moisture infiltration. In order to investigate the correlation between interfacial properties and immersion stability of asphalt mixture, three different types of fiber, including basalt fiber (BF), glass fiber (GF), and polyester fiber (PF); five types of fiber contents (0.1% to 0.
View Article and Find Full Text PDFDynamic Mechanical Properties and Energy Absorption Capabilities of Polyureas Through Experiments and Molecular Dynamic Simulation.
Polymers (Basel)
January 2025
State Key Laboratory of Chemical Safety, Qingdao 266000, China.
Polyurea (PUR) has been widely used as a protective coating in recent years. In order to complete the understanding of the relationship between PUR microstructure and its energy absorption capabilities, the mechanical and dynamic performance of PURs containing various macrodiol structural units were compared using material characterization techniques and molecular dynamic simulation. The results showed that the PUR polycarbonate diols formed as energy absorbing materials showed high tensile strength, high toughness, and excellent loss factor distribution based on the comparison of stress-strain tensile curves, glass transition temperatures, phase images, and dynamic storage loss modulus.
View Article and Find Full Text PDFSynergistic enhancement of hydrophobicity and mechanical properties of cellulose paper by (3-glycidoxypropyl) trimethoxy and rosin.
Int J Biol Macromol
January 2025
College of Biological Engineering, Sichuan University of Science and Engineering, Yibin, Sichuan 644005, China. Electronic address:
Cellulose-based paper is inherently poor in hydrophobicity and mechanical strength, limiting its practical applications in daily life such as packaging materials, water-resistant labels, and disposable tableware. This study aimed to develop an effective and eco-friendly strategy to address these limitations by enhancing the hydrophobicity and mechanical properties of cellulose paper. To achieve this, an internal sizing agent was prepared by combining (3-glycidoxypropyl) trimethoxy (GPS) with natural rosin.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!