Dilemmas in zirconia bonding: A review

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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Ranking Cultivated Blueberry for Mummy Berry Blight and Fruit Infection Incidence Using Resampling and Principal Components Analysis

HortScience ◽

10.21273/hortsci.45.8.1205 ◽

2010 ◽

Vol 45 (8) ◽

pp. 1205-1210 ◽

Cited By ~ 9

Author(s):

Mark K. Ehlenfeldt ◽

James J. Polashock ◽

Allan W. Stretch ◽

Matthew Kramer

Keyword(s):

Principal Component Analysis ◽

Principal Component ◽

The Other ◽

Breeding Strategies ◽

Relative Resistance ◽

Term Variation ◽

Components Analysis ◽

Infection Stage ◽

Selection Of

Mummy berry disease of blueberry has two distinct phases: a blighting phase that infects emerging shoots and leaves early in the spring and a flower infection phase that ultimately leads to infected (mummified) fruit. Cultivated blueberry (Vaccinium spp.) genotypes that are resistant to one phase are not necessarily resistant to the other phase. The resistance of cultivated blueberry (Vaccinium spp.) genotypes to each phase of the disease is different. A large number of cultivars were screened for resistance to each phase. Cultivar standards (cultivars with well-documented responses to the disease) were used in the screening to evaluate long-term variation and aid comparisons across years. Using nine standards for the blight phase, 125 cultivars were tested and ranked for relative resistance using a ranking system based on resampling and principal component analysis. Similarly, using six standards for the flower/fruit infection stage, 110 blueberry cultivars were tested and ranked for relative resistance. Cultivar rankings show that lowbush cultivars and other types possessing high percentages of lowbush germplasm are generally more resistant to both phases of the disease. Among highbush cultivars, Bluejay is reliably resistant to both phases. Documentation of resistance to each phase will allow selection of cultivars for planting in affected areas and will facilitate the development of breeding strategies to produce cultivars with superior resistance.

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Zirconia Dental Implant Materials

Materials Science Forum ◽

10.4028/www.scientific.net/msf.907.99 ◽

2017 ◽

Vol 907 ◽

pp. 99-103

Author(s):

Sergiu Ciprian Focșăneanu ◽

Petrică Vizureanu ◽

Andrei Victor Sandu ◽

Mădălina Simona Bălţatu

Keyword(s):

Mechanical Properties ◽

Mechanical Strength ◽

Dental Implants ◽

Clinical Studies ◽

Glass Ceramics ◽

Ceramic Materials ◽

Medical Applications ◽

Dental Restorations ◽

Esthetic Dentistry ◽

Titanium Dental Implants

Ceramic materials are used for the fabrication of dental restorations respectively esthetic dentistry. The main ceramic materials are glass ceramics, spinel, alumina and zirconia. Zirconia was introduced into dentistry domain in the 1990s used like frameworks, implants, dowels, abutments and orthodontic brackets. Recently, zirconia materials are getting much attention for dental implants because of its toothlike color, mechanical properties, good corrosion and biocompatibility. This article presents an review of zirconia dental implants osseointegration and mechanical strength compared with other dental implants. Clinical studies published indicate that zirconia dental implants have the potential to become alternative of titanium dental implants used in medical applications.

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Effect of thermocycling on bond strength of luting cements to zirconia ceramic

Dental Materials ◽

10.1016/j.dental.2005.04.016 ◽

2006 ◽

Vol 22 (2) ◽

pp. 195-200 ◽

Cited By ~ 187

Author(s):

H LUTHY ◽

O LOEFFEL ◽

C HAMMERLE

Keyword(s):

Bond Strength ◽

Zirconia Ceramic ◽

Luting Cements

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Light Transmission of Various Aesthetic Posts at Different Depths and Its Effect on Push-Out Bond Strength, Microhardness of Luting Cement

Medicina ◽

10.3390/medicina58010075 ◽

2022 ◽

Vol 58 (1) ◽

pp. 75

Author(s):

Satheesh B. Haralur ◽

Turki Abdullah Alasmari ◽

Mohammed Hussin Alasmari ◽

Hafiz Mohammed Hakami

Keyword(s):

Bond Strength ◽

Light Transmission ◽

Testing Machine ◽

Resin Cement ◽

Light Transmittance ◽

Zirconia Ceramic ◽

Luting Cements ◽

Luting Cement ◽

Different Depths ◽

Push Out

Background and Objectives: One requirement for the cemented post is the light transmittance on its entire length up to the deepest portion of a root canal to ensure the complete polymerization of resin cement. This study aimed to determine the light transmission ability in different aesthetic posts at different depths and its effect on the push-out bond strength and microhardness of luting cement at the corresponding interface. Materials and Methods: Twenty endodontic posts from glass fiber posts (GFP), zirconia ceramic posts (ZCP), and highly translucent zirconium oxide posts (HTZP) were sequentially sectioned into 12.8 and 4 mm lengths after recording the light intensity using a dental radiometer. Sixty single rooted premolar teeth root canals were treated and implanted vertically in a resin block. The post space was prepared and cemented with GFP, ZCP, and HTZP posts with twenty samples each. The root portion of teeth samples were sectioned into cervical, middle, and apical portion. A universal testing machine was utilized for the push-out bond strength test for the first ten samples from each group. The remaining ten samples from each group were used for the microhardness test using a micro-indenter instrument. The data were statistically analyzed using one-way Analysis of variance and Tukey HSD tests at p < 0.05. Results: The GFP endodontic postpresented with significant highest light translucency compared to HTZP, which was significantly higher than ZCP. GFP posts showed significantly higher bond strength per unit area compared to ZCP at analogous cross sections. The hardness of luting cement was also significantly higher amongst all tested endodontic posts. Conclusions: GFP high light translucency enhanced the curing of the luting resin cement that resulted in harder cement and a stronger bond supported by hardness and push-out tests. These findings suggest that GFP is preferred to be used with light-cured luting cements for restoration of endodontically treated teeth.

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Using the best linear predictor (BLP) in the selection between and among half-sib progenies of the CMS-39 maize population

Brazilian Journal of Genetics ◽

10.1590/s0100-84551997000400021 ◽

1997 ◽

Vol 20 (4) ◽

pp. 683-690

Author(s):

Cleso Antônio Patto Pacheco ◽

José Ivo Ribeiro Júnior ◽

Cosme Damião Cruz

Keyword(s):

Variance Component ◽

Genetic Variance ◽

Additive Genetic Variance ◽

The Other ◽

Linear Predictor ◽

Selection Cycle ◽

Maize Population ◽

Best Linear Predictor ◽

Selection Of

Data of corn ear production (kg/ha) of 196 half-sib progenies (HSP) of the maize population CMS-39 obtained from experiments carried out in four environments were used to adapt and assess the BLP method (best linear predictor) in comparison with to the selection among and within half-sib progenies (SAWHSP). The 196 HSP of the CMS-39 population developed by the National Center for Maize and Sorghum Research (CNPMS-EMBRAPA) were related through their pedigree with the recombined progenies of the previous selection cycle. The two methodologies used for the selection of the twenty best half-sib progenies, BLP and SAWHSP, led to similar expected genetic gains. There was a tendency in the BLP methodology to select a greater number of related progenies because of the previous generation (pedigree) than the other method. This implies that greater care with the effective size of the population must be taken with this method. The SAWHSP methodology was efficient in isolating the additive genetic variance component from the phenotypic component. The pedigree system, although unnecessary for the routine use of the SAWHSP methodology, allowed the prediction of an increase in the inbreeding of the population in the long term SAWHSP selection when recombination is simultaneous to creation of new progenies.

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Study of The Effect of TiO2 Addition On The Crystalline Phases, Structure and Chemical Durability of a Nuclear Glass Ceramic

10.21203/rs.3.rs-861278/v1 ◽

2021 ◽

Author(s):

Rafika SOUAG ◽

Nour elhayet KAMEL ◽

Dalila Moudir ◽

Yasmina MOUHEB ◽

Fayrouz Aouchiche

Keyword(s):

Glass Ceramic ◽

Glass Ceramics ◽

Ceramic Materials ◽

Chemical Durability ◽

Aluminosilicate Glass ◽

High Level Waste ◽

X Ray Diffraction ◽

Complex Chemical Composition ◽

High Level ◽

Selection Of

Abstract This study focused on the effect of TiO 2 addition on the crystallines phases’ formation, structure and chemical durability of a nuclear glass ceramic constituted by an aluminosilicate glass in the system: SiO2-Al2O3-CaO-MgO-ZrO2-TiO2 . The materials with four contents of TiO2 , ranging from 4.11 to 7.11 wt.%, are synthesized by a discontinuous method,. For the whole of materials, X-ray diffraction analysis allow identifying an aluminosilicate belonging to pyroxenes silicates family as a main phase, powelite and calzirtite. Both SEM and DTAanalyses confirmed these results. The materials FTIR analysis reveals the glass ceramics complex chemical composition. MCC1 and MCC2 tests, performed on selected glass ceramic materials, indicate that the materials with 4.11 and 5.11 wt.% TiO2 are the most durable against Si, Al, Mg and Ce elements release, in MCC2 test; The results make conclusions valuable on the selection of such glass ceramics as candidate for the disposal of high-level waste.

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Choosing a Suitable Ultramicrotome, Associated Equipment and the Proper Laboratory Environment for Operation of the System

Microscopy and Microanalysis ◽

10.1017/s1431927600024612 ◽

1998 ◽

Vol 4 (S2) ◽

pp. 898-899

Author(s):

John J. Bozzola

Keyword(s):

The Other ◽

Clear Indication ◽

Short Term ◽

Laboratory Environment ◽

Other Hand ◽

Future Requirement ◽

One Year ◽

Selection Of

The selection of an ultramicrotome should always begin with an evaluation of the immediate as well as the long-term needs of the laboratory. If present projects require ultramicrotomy on a regular basis (e.g., more than 5-10 specimens per week) and if this demand will probably continue for more than one year, the acquisition of an ultramicrotome is justified. An intensive, short-term project or an occasional need with no clear indication of a future requirement for ultramicrotomy could best be accommodated by either leasing an ultramicrotome or contracting the work to an individual or corporation. On the other hand, several laboratories with modest needs may wish to pool resources and purchase a shared instrument capable of fulfilling the requirements of each lab.Since new ultramicrotomes cost $20k and up, one may be compelled to acquire a used instrument. Depending upon the age and condition, a used ultramicrotome may be purchased at a cost of $2-15k.

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The effect of synchronising the supply of energy and protein to the rumen on the short and long-term diet selection of sheep

Proceedings of the British Society of Animal Science ◽

10.1017/s0308229600030191 ◽

1996 ◽

Vol 1996 ◽

pp. 46-46

Author(s):

I. Kyriazakis ◽

D.H. Anderson ◽

M. Lewis ◽

J.D. Oldham ◽

T.G. Papachristou ◽

...

Keyword(s):

Diet Selection ◽

Mature Female ◽

The Other ◽

Carbohydrate Source ◽

Fresh Food ◽

Beet Pulp ◽

Ruminant Animals ◽

Carbohydrate Fermentation ◽

Selection Of

An experiment was carried out to investigate the hypothesis that the diet selection of ruminant animals from two foods of different rapidly rumen degradable protein contents could be affected by the differences in the rate of synchrony between carbohydrate fermentation and degradation of protein in the rumen. The diet selection of the animals was measured both in the 'long-term' (daily) and 'short-term' (2h intervals within the day).Twelve rumen fistulated mature female sheep (liveweight 59.1 kg) were used. Four foods (A,B,C and D) with the same ME (9.6 MJ/kg fresh food) and similar, high metab/sable protein contents were made into pellets. Two of the foods were based on a rapidly fermentable carbohydrate source (barley, A and B foods) and the other two on a slowly fermentable carbohydrate source (plain sugar beet pulp, C and D foods). Within each source one food (A or C) had a low (70) and the other a high (140 g/kg) concentration of effective rumen degradable content (RDP).

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Long-term influence of associating an antibacterial agent with GIC on bond strength to caries-affected dentin

Brazilian Journal of Oral Sciences ◽

10.20396/bjos.v16i0.8651063 ◽

2017 ◽

Vol 16 ◽

pp. 1-10

Author(s):

Ana Carolina de Oliveira Becci ◽

Luana Mafra Marti ◽

Angela Cristina Cilense Zuanon ◽

Fernanda Lourenção Brighenti ◽

Elisa Maria Aparecida Giro

Keyword(s):

Bond Strength ◽

Failure Modes ◽

Multiple Comparisons ◽

The Other ◽

Chi Square ◽

Chi Square Test ◽

Term Evaluation ◽

Storage Methods ◽

Microshear Bond Strength

Aim: To evaluate the bond strength of a GIC associated with chlorhexidine (CHX) to sound and caries-affected dentin, immediately and after six months of storage. Methods: Sixty molars were assigned to two groups of 30 teeth. One had flat dentin surfaces produced and submitted to caries induction to obtain a caries-affected dentin. In the other group dentin was maintained sound. Teeth of each group were randomly reassigned to three subgroups (n=10) according to the concentration of CHX added to the GIC (0%, 1% and 2% by weight). Two specimens (1mm diameter x 1 mm high) of the same material were constructed on each dentin surface. One was submitted to the microshear bond strength (µSBS) test after 24 hours and the other after 6 months of storage in water at 37oC. Failure modes were analyzed under a stereomicroscope. Bond strength data were analyzed by three-way ANOVA followed by Games-Howell tests for multiple comparisons, and failure modes by the Chi-square test (α = 0.05). Results: The µSBS values obtained to sound dentin were higher compared with those to caries-affected dentin (p≤0.001). In sound dentin, the group with 2% CHX showed lower µSBS values compared with 0% and 1% CHX after 24 hours (p=0.005 and p=0.032 respectively). In caries-affected dentin, after 24 hours, µSBS in group with 1% CHX was statistically higher than the values in groups with 2% CHX after 24 hours (p=0.001) and 1% CHX after 6 months (p=0.024). Irrespective of the condition of substrate, comparisons showed no statistically significant differences between the other groups (p≥0.053). Cohesive in material and mixed failures prevailed for all groups. Conclusions: The addition of CHX at concentrations of up to 2% to the GIC did not affect the bond strength of the material to sound and caries-affected dentin in a long-term evaluation.

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