Effects of low-temperature degradation on the surface roughness of yttria-stabilized tetragonal zirconia polycrystal ceramics: A systematic review and meta-analysis

The objective of the present article is to study the influence of TiB2 addition on the transformation behavior of yttria stabilized tetragonal zirconia polycrystals (Y-TZP). A range of TZP(Y)–TiB2 composites with different zirconia starting powder grades and TiB2 phase contents (up to 50 vol%) were processed by the hot-pressing route. Thermal expansion data, as obtained by thermo-mechanical analysis were used to assess the ZrO2 phase transformation in the composites. The thermal expansion hysteresis of the transformable ceramics provides information concerning the transformation behavior in the temperature range of the martensitic transformation and the low-temperature degradation. Furthermore, the transformation behavior and susceptibility to low-temperature degradation during thermal cycling were characterized in terms of the overall amount and distribution of the yttria stabilizer, zirconia grain size, possible dissolution of TiB2 phase, and the amount of residual stress generated in the Y-TZP matrix due to the addition of titanium diboride particles. For the first time, it is demonstrated in the present work that the thermally induced phase transformation of tetragonal zirconia in the Y-TZP composites can be controlled by the intentional addition of the monoclinic zirconia particles into the 3Y-TZP matrix.

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Do denture cleansers influence the surface roughness and adhesion and biofilm formation of Candida on acrylic resin? Protocol for a systematic review and meta-analysis

10.37766/inplasy2021.2.0039 ◽

2021 ◽

Author(s):

Amanda Ferro ◽

Juliana Padilha ◽

Beatriz Ribas ◽

Lais Scabelo ◽

Janaina Jorge

Keyword(s):

Systematic Review ◽

Surface Roughness ◽

Biofilm Formation ◽

Meta Analysis ◽

Acrylic Resin ◽

Denture Cleansers

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Low-temperature degradation in yttria-stabilized tetragonal zirconia polycrystal doped with small amounts of alumina: Effect of grain-boundary energy

Journal of the European Ceramic Society ◽

10.1016/j.jeurceramsoc.2015.09.016 ◽

2016 ◽

Vol 36 (1) ◽

pp. 155-162 ◽

Cited By ~ 8

Author(s):

Koji Matsui ◽

Kazuto Nakamura ◽

Akihito Kumamoto ◽

Hidehiro Yoshida ◽

Yuichi Ikuhara

Keyword(s):

Low Temperature ◽

Grain Boundary ◽

Boundary Energy ◽

Tetragonal Zirconia ◽

Grain Boundary Energy ◽

Tetragonal Zirconia Polycrystal

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PROSPERO Protocol - Can surface gloss measurements predict effectiveness of finishing/polishing protocols in direct restorations? A systematic review

10.31219/osf.io/4kvcb ◽

2021 ◽

Author(s):

Teresa Pinheiro de Melo ◽

António Delgado

Keyword(s):

Systematic Review ◽

Surface Roughness ◽

Meta Analysis ◽

Resin Composites ◽

Surface Gloss

The document enclosed is a PROSPERO registration document of an in vitro systematic review and meta-analysis concerning gloss and surface roughness of resin composites used in dentistry.

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Effects of Aging on the Color and Translucency of Monolithic Translucent Y-TZP Ceramics: A Systematic Review and Meta-Analysis of In Vitro Studies

BioMed Research International ◽

10.1155/2021/8875023 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Chang-yuan Zhang ◽

Check Agingu ◽

James Kit Hon Tsoi ◽

Hao Yu

Keyword(s):

Systematic Review ◽

Meta Analysis ◽

Tetragonal Zirconia ◽

In Vitro Studies ◽

Cochrane Library ◽

Hydrothermal Aging ◽

Significant Difference ◽

Effects Of Aging ◽

Meta Analyses

Background. Monolithic restorations made of translucent yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) have become popular over the past few decades. However, whether aging affects the color and translucency of monolithic translucent Y-TZP is unclear. Objective. The aim of this systematic review and meta-analysis of in vitro studies was to evaluate the effects of aging on the color and translucency of monolithic translucent Y-TZP ceramics. Materials and Methods. This systematic review/meta-analysis was reported according to the PRISMA statement and registered in the OSF registries (https://osf.io/5qjmu). Four databases including Medline via the PubMed, Embase, and Web of Science databases and the Cochrane Library were searched using no publication year and language limits. The last search was executed on November 20, 2020. In vitro studies comparing the translucency and/or color of monolithic translucent Y-TZP ceramics before and after simulated aging were selected. Meta-analyses were performed using Review Manager software (version 5.3, Cochrane Collaboration, Oxford, UK) with random-effects models at a significance level of 0.05. A risk-of-bias assessment was also performed for the included studies. Results. Of the 188 potentially relevant studies, 13 were included in the systematic review. The hydrothermal aging duration ranged from 1 to 100 h at relatively similar temperatures (~134°C). In the general meta-analyses, the aged Y-TZP ceramics exhibited similar translucency parameter (TP), L ∗ , and b ∗ values compared with the nonaged controls ( P = .73 , P = .49 , and P = .62 , respectively). Moreover, there was a significant difference between the aged and nonaged Y-TZP ceramics in the a ∗ value ( P = .03 ; MD = − 0.26 ; 95% CI = − 0.51 to − 0.02 ), favoring the nonaged Y-TZP ceramics. The subgroup analyses showed that the duration of aging contributed to changes in the translucency and color of the Y-TZP ceramics. Conclusions. The optical properties of monolithic translucent Y-TZP ceramics were stable after hydrothermal aging at 134°C and 0.2 MPa for ≤20 h. Moreover, clinically unacceptable changes in the translucency and color of monolithic translucent Y-TZP ceramics were found after hydrothermal aging for >20 h.

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