Low‐Temperature Aging of Y‐TZP Ceramics

Chevalier, Jérôme; Calès, B.; Drouin, Jean Michel

doi:10.1111/j.1151-2916.1999.tb02055.x

Cited by 627 publications

(654 citation statements)

References 20 publications

(22 reference statements)

Supporting

Mentioning

586

Contrasting

Unclassified

Order By: Relevance

“…Many studies reported that the major disadvantage of Y-TZP is its reduced stability against low temperature degradation (LTD) [31,[35][36][37][38]. LTD is defined as the spontaneous tetragonal to monoclinic transformation occurring over time at low temperatures, when the transformation is not triggered by the local stress produced at the trip of the advancing crack [2].…”

Section: Discussionmentioning

confidence: 99%

“…Under hydrothermal changes, an undesired phase transformation from tetragonal phase to the weaker monoclinic zirconia can occur on the surface of the monoclinical zirconia FDPs. This is combined with an increase in the surface roughness [37] resulting possibly in high abrasion of the antagonist enamel. Moreover, through the undesired phase transformation as a result of aging, mechanical properties may decrease further [37,38].…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

The effect of zirconia sintering temperature on flexural strength, grain size, and contrast ratio

et al. 2012

View full text Add to dashboard Cite

OBJECTIVE: This study investigated the effect of sintering temperatures on flexural strength, contrast ratio, and grain size of zirconia. MATERIALS AND METHODS: Zirconia specimens (Ceramill ZI, Amann Girrbach) were prepared in partially sintered state. Subsequently, the specimens were randomly divided into nine groups and sintered with different final sintering temperatures: 1,300°C, 1,350°C, 1,400°C, 1,450°C, 1,500°C, 1,550°C, 1,600°C, 1,650°C, or 1,700°C with 120 min holding time. Three-point flexural strength (N = 198; n = 22 per group) was measured according to ISO 6872: 2008. The contrast ratio (N = 90; n = 10 per group) was measured according to ISO 2471ISO : 2008. Grain sizes and microstructure of different groups were investigated (N = 9, n = 1 per group) with scanning electron microscope. Data were analyzed using one-way ANOVA with Scheffé test and Weibull statistics (p < 0.05). Pearson correlation coefficient was calculated between either flexural strength or contrast ratio and sintering temperatures. RESULTS: The highest flexural strength was observed in groups sintered between 1,400°C and 1,550°C. The highest Weibull moduli were obtained for zirconia sintered at 1,400°C and the lowest at 1,700°C. The contrast ratio and the grain size were higher with the higher sintering temperature. The microstructure of the specimens sintered above 1,650°C exhibited defects. Sintering temperatures showed a significant negative correlation with both the flexural strength (r = -0.313, p < 0.001) and the contrast ratio values (r = -0.96, p < 0.001). CONCLUSIONS: The results of this study showed that the increase in sintering temperature increased the contrast ratio, but led to a negative impact on the flexural strength. CLINICAL RELEVANCE: Considering the flexural strength values and Weibull moduli, the sintering temperature for the zirconia tested in this study should not exceed 1,550°C. 20]. In fact, the stability of the complete system consisting both the zirconia framework and the veneering ceramic is of clinical importance.In order to decrease the costs and at the same time overcome the chipping problem, it is possible today to produce zirconia FDPs without veneering ceramic.Such monolithic zirconia FDPs require higher translucency with superior mechanical properties especially when they are to be used in the anterior region. Framework translucency is therefore one of the primary factors with respect to aesthetic properties in the selection of dental materials [21,22]. The translucency of dental ceramic is highly dependent on light scattering [23]. When the majority of light passing through a ceramic is intensely scattered and diffusely reflected, the material would appear opaque. However, if only part of the light is scattered and most of it is diffusely transmitted, the material would appear translucent where Y B was the value with a black background, and Y w was the value with a white background. In all calculations, 0 was considered as totally transparent and 1 as

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

The effect of zirconia sintering temperature on flexural strength, grain size, and contrast ratio

et al. 2012

View full text Add to dashboard Cite

show abstract

“…For testing the aging behavior after the different surface treatments, the samples were exposed to artificial degradation in autoclave under water vapor at 134 ºC and 2 bar pressure for 30 h. This time was chosen to represent more than the expected life of the application, since it corresponds roughly with 60 years in vivo (Chevalier et al, 1999). After the treatment, the monoclinic phase volume fraction (Vm%) near the surface was measured with XRD by applying the equation of Toraya et al (Toraya et al, 1984) and results were analyzed as in the previous section.…”

Section: Aging Studiesmentioning

confidence: 99%

Surface roughened zirconia: towards hydrothermal stability

Camposilvan

Flamant

Anglada

2015

Journal of the Mechanical Behavior of Biomedical Materials

View full text Add to dashboard Cite

Surface roughness is needed in several yttria-stabilized zirconia components used in restorative dentistry for osseointegration or adhesion purposes. This can be achieved by different treatments, which may also modify the microstructure of the surface. Among them, sandblasting and chemical etching are widely used, but their effect on hydrothermal aging of zirconia is not fully understood. In the present work, the zirconia long-term stability of rough surfaces prepared by these techniques is analyzed and a method is proposed for preventing hydrothermal aging while maintaining the original surface appearance and mechanical properties. The method involves pressure infiltration of a Cerium salt solution on the roughened surfaces followed by a thermal treatment. The solution, trapped by surface defects and small pores, is decomposed during thermal treatment into Cerium oxide, which is diffused at high temperature, obtaining Ce co-doping in the near-surface region.In addition, the microstructural changes induced in the near-surface by sandblasting or chemical etching are removed by the thermal treatment together with surface defects. No color modification was observed and the final roughness parameters were in the range of existing implants of proved good osseointegration. The aging resistance of Ce co-doped materials was strongly enhanced, showing the absence of aging after artificial degradation, increasing in this way the surface mechanical integrity.The proposed treatment is easily applicable to the current manufacturing procedures of zirconia dental posts, abutments, crowns and dentures, representing a solution to hydrothermal aging in these and other biomedical applications.

show abstract

“…[32] it roughly compares to 60 years in vivo, (note that this equivalence holds only for stress-free materials). X-Ray Diffraction (XRD) patterns were collected before and after the exposure with a Bruker D8 Advance diffractometer using Cu-K radiation and /2 configuration.…”

Section: Characterizationmentioning

confidence: 99%

Enhanced reliability of yttria-stabilized zirconia for dental applications

et al. 2015

View full text Add to dashboard Cite

An increasing number of dental applications based on yttria-stabilized zirconia (3Y-TZP) have been developed in recent years as a result of the advances and versatility of dry-processing and soft machining at the pre-sintered state. Nonetheless, the long-term surface stability of these materials in humid environment is still a matter of concern and may limit its application. In this work, a simple method to prevent hydrothermal degradation on zirconia surface is studied in detail. This method involves the infiltration of pre-sintered parts with optimized solutions containing Ce salts, leaving unchanged the other processing steps, allowing the diffusion of Ce during conventional sintering. Several pre-sintering conditions, solution concentrations and sintering temperatures were studied and characterized, obtaining working parameters for the production of zirconia parts with mechanical properties similar to standard 3Y-TZP and high resistance to hydrothermal aging. This optimal combination was obtained with the 1150 ºC pre-sintering temperature, 50 wt% solution and sintering at 1450 ºC, leading to a superficial CeO 2 content of about 3 mol%.

show abstract

Low‐Temperature Aging of Y‐TZP Ceramics

Cited by 627 publications

References 20 publications

The effect of zirconia sintering temperature on flexural strength, grain size, and contrast ratio

The effect of zirconia sintering temperature on flexural strength, grain size, and contrast ratio

Surface roughened zirconia: towards hydrothermal stability

Enhanced reliability of yttria-stabilized zirconia for dental applications

Contact Info

Product

Resources

About