Long-term dimensional stability and longitudinal uniformity of line scales made of glass ceramics

Length measurement was conducted for two years on glass ceramics, Zerodur®and Clearceram®, which have a low coefficient of thermal expansion, and on synthetic quartz. Commercially available glass ceramics were used for evaluating long-term stability, or secular change. Synthetic quartz ensured longterm length measurement stability. Two line scales of 300 mm length made of each material for a total of six line scales were simultaneously manufactured and measured to evaluate dimensional stability variation of the materials over time. Measurements were conducted with a line scale calibration systemdeveloped by Nikon. The calibration system is a onedimensional laser interferometer, featuring reduced Abbe’s errors, laser interferometer paths in a vacuum and real-time wavelength calibration of laser frequency using a 633 nm iodine-stabilized He-Ne laser. Long-term quartz stability was 4.3 nm and 5.4 nm (2σ). The yearly stability coefficients of the two glassceramic scales were -0.22 and -0.23 parts per million per year (ppm/yr) for Zerodur and -0.16 and -0.16 ppm/yr for Clearceram. No significant difference in stability between the two scales was observed for Zerodur or Clearceram.

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High Bond Durability of Universal Adhesives on Glass Ceramics Facilitated by Silane Pretreatment

Operative Dentistry ◽

10.2341/17-227-l ◽

2018 ◽

Vol 43 (6) ◽

pp. 602-612 ◽

Cited By ~ 5

Author(s):

C Yao ◽

H Yang ◽

J Yu ◽

L Zhang ◽

Y Zhu ◽

...

Keyword(s):

Laser Scanning ◽

Glass Ceramics ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Single Bond ◽

Thermal Cycles ◽

Universal Adhesive ◽

Universal Adhesives ◽

Resin Bonding

SUMMARY Objective: This study aimed to investigate the long-term effectiveness of ceramic–resin bonding with universal adhesives in non–silane-pretreated and silane-pretreated modes after 10,000 cycles of thermal aging. Methods and Materials: All Bond Universal, Adhese Universal, Clearfil Universal Bond, and Single Bond Universal were selected. Etched lithium disilicate glass ceramics were prepared, randomly assigned to groups, and pretreated with or without ceramic primer containing silane coupling agent prior to the application of universal adhesive (ie, silane-pretreated or non–silane-pretreated mode). The shear bond strength (SBS), microleakage, and field-emission scanning electron microscopy images of the ceramic–resin interfaces were examined after 24 hours of water storage or 10,000 thermal cycles. Light microscopy and confocal laser scanning microscopy (CLSM) were performed to analyze marginal sealing ability. Results: SBS and microleakage percentage were significantly affected by bonding procedure (non–silane-pretreated or silane-pretreated mode) and aging (24 hours or 10,000 thermal cycles). After the universal adhesives in the non–silane-pretreated mode were aged, SBS significantly decreased and microleakage percentage increased. By contrast, the SBS of Adhese Universal, Clearfil Universal Bond, and Single Bond Universal decreased, and the microleakage percentage of all of the adhesives increased in the silane-pretreated mode. However, after aging, the SBS of the silane-pretreated groups were higher and their microleakage percentages lower than those of the non–pretreated groups. In the non–silane-pretreated mode, adhesive failure was dominant and gaps between composite resin and the adhesive layer were significant when observed with CLSM. Conclusions: The simplified procedure reduced the ceramic–resin bonding effectiveness of universal adhesives after aging, and additional silane pretreatment helped improve the long-term durability.

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Dilemmas in zirconia bonding: A review

Srpski arhiv za celokupno lekarstvo ◽

10.2298/sarh1306395o ◽

2013 ◽

Vol 141 (5-6) ◽

pp. 395-401 ◽

Cited By ~ 8

Author(s):

Kosovka Obradovic-Djuricic ◽

Vesna Medic ◽

Slobodan Dodic ◽

Dragan Gavrilov ◽

Djordje Antonijevic ◽

...

Keyword(s):

Bond Strength ◽

Glass Ceramics ◽

Ceramic Materials ◽

The Other ◽

Zirconia Ceramic ◽

Bonding Mechanism ◽

Luting Cements ◽

Esthetic Dentistry ◽

Selection Of

This article presents a literature review on the resin bond to zirconia ceramic. Modern esthetic dentistry has highly recognized zirconia, among other ceramic materials. Biocompatibility of zirconia, chemical and dimensional stability, excellent mechanical properties, all together could guarantee optimal therapeutical results in complex prosthodontic reconstruction. On the other hand, low thermal degradation, aging of zirconia as well as problematic bonding of zirconia framework to dental luting cements and tooth structures, opened the room for discussion concerning their clinical durability. The well known methods of mechanical and chemical bonding used on glass-ceramics are not applicable for use with zirconia. Therefore, under critical clinical situations, selection of the bonding mechanism should be focused on two important points: high initial bond strength value and long term bond strength between zirconia-resin interface. Also, this paper emphases the use of phosphate monomer luting cements on freshly air-abraded zirconia as the simplest and most effective way for zirconia cementation procedure today.

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Long-term stability analysis and its relationship with the steel structure of gauge blocks from several manufacturers

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1193/1/012077 ◽

2021 ◽

Vol 1193 (1) ◽

pp. 012077

Author(s):

A Mínguez ◽

J Moreno ◽

J De Vicente

Keyword(s):

Stability Analysis ◽

Statistical Method ◽

Dimensional Stability ◽

Steel Structure ◽

Metallographic Analysis ◽

Measuring Instruments ◽

Dimensional Metrology ◽

Long Term Stability ◽

History Of

Abstract Gauge blocks are one of the most widespread measurement standards (etalons) in dimensional metrology laboratories. Among all its properties, it is worth highlighting the importance of dimensional stability. This property allows to classify these measuring instruments in quality grades. Although the gauge blocks should be dimensionally stable, it can be observed that there is a drift that can be observed when the calibration history is revised. In this document, authors present a statistical method for the estimation of the dimensional stability of gauge blocks using the calibration history of samples from the main manufacturers. In addition, all the samples have been subjected to metallographic analysis to evaluate the structure.

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The Dimensional Stability and Durability of Acrylic Resins for the Injection of Cementitious Systems

European Journal of Engineering and Formal Sciences ◽

10.26417/ejef.v4i1.p75-78 ◽

2020 ◽

Vol 4 (1) ◽

pp. 75

Author(s):

C. S. Paglia ◽

A. Krattiger

Keyword(s):

Dimensional Stability ◽

Crack Formation ◽

General Increase ◽

Acrylic Resins ◽

Material Stiffness ◽

Cent Relative Humidity ◽

Term Basis ◽

Cyclic Variations ◽

Cementitious Systems

The dimensional stability and durability of Acrylamide- and Methacrylate-based acrylic resins have been studied. The dimensional stability was characterized by measuring the volume expansion of samples immersed in water for a period up to 240 days or by exposing the samples to 23oC and 50 per cent, 90 per cent relative humidity and by monitoring the shrinkage. The durability was investigated by exposing the resins to cyclic variations of temperature in air and in water. The resins generally exhibit a significant volume change up to 160 per cent of the initial volume when immersed in water or exposed to a relatively dry atmosphere (23oC and 50 per cent). A general increase in the material stiffness and/or crack formation on the surface of the resin is observed. On a long-term basis, the durability of the resins may significantly vary with occasionally a partial or complete deterioration of the some resins. A general better dimensional stability and durability is observed for the Methacrylate-based resins as compared to the Acrylamide-based resins.

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