Abstract：
OBJECTIVES:To determine the correlation between fracture toughness and leucite content in dental porcelains. The mechanisms by which leucite influences the fracture toughness of dental porcelains were also investigated. METHODS:Six porcelains were tested: A (Ceramco I/Dentsply), B (Ceramco II/Dentsitply), C (Finesse/Dentsply), D (d.Sign/Ivoclar), Cb (Cerabien/Noritake) and V (Vitadur Alpha/Vita). Bar-shaped specimens were produced, and their fracture toughness was determined by means of the single-edge precracked beam (SEPB) method. The test consisted of fracturing the specimen after a precrack was generated by a bridge-anvil device. KIc was calculated based on fracture force and size of the precrack. Microstructural analysis and determination of the leucite volume fraction were performed on polished specimens etched with 2% HF for 15s by means of scanning electron microscopy. Fractographic analysis was performed on fracture surfaces. RESULTS:Porcelains A and B presented the highest leucite contents (22%) and similar KIc values (1.23 and 1.22 MPa m1/2, respectively), significantly higher than the other materials. Porcelains C and D presented similar K(Ic) values (0.81 and 0.93 MPa m1/2, respectively), but different leucite contents (6 and 15%, respectively). Porcelain D presented higher KIc compared to porcelains Cb and V (0.71 and 0.75 MPa m1/2, respectively), which presented similar values and the lowest leucite contents (0%). Fractographic analysis showed that porcelains with higher leucite content presented higher incidence of crack deflection. CONCLUSIONS:For the materials evaluated in this study, the leucite content was directly related to KIc. The main toughening mechanism observed was crack deflection around leucite particles and clusters.
journal_name
J Dentjournal_title
Journal of dentistryauthors
Cesar PF,Yoshimura HN,Miranda Júnior WG,Okada CYdoi
10.1016/j.jdent.2005.02.001keywords:
subject
Has Abstractpub_date
2005-10-01 00:00:00pages
721-9issue
9eissn
0300-5712issn
1879-176Xpii
S0300-5712(05)00050-3journal_volume
33pub_type
杂志文章abstract：OBJECTIVES:In some studies gap formation has been evaluated in just one section of the restorative. This in vitro study aimed to design a quantitative three-dimensional method for evaluation of the contraction gap in restoratives. METHODS:Cervical cavities were prepared on buccal, palatal or lingual surfaces in human ...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2004.10.001
更新日期：2005-04-01 00:00:00
abstract：OBJECTIVES:To investigate the effect of saliva substitutes on enamel erosion in vitro. METHODS:A total of 204 bovine enamel samples were embedded in acrylic resin and allocated to 17 groups (n=12). The specimens were eroded in an artificial mouth (3 days; 6×30 s/days, flow rate: 2 ml/min) using citric acid (pH: 2.5). ...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2014.03.012
更新日期：2014-06-01 00:00:00
abstract：OBJECTIVES:Probiotics might be beneficial to prevent or treat caries, gingivitis or periodontitis. We aimed to appraise trials assessing probiotics for managing caries and periodontal disease. DATA:We included randomized controlled trials comparing the efficacy of probiotics versus (placebo) control with regards to St...
journal_title：Journal of dentistry
pub_type： 杂志文章,meta分析,评审
doi：10.1016/j.jdent.2016.03.002
更新日期：2016-05-01 00:00:00
abstract：OBJECTIVE:To compare the effect of QMix (Dentsply Sirona), 7% maleic acid (MA), and 17% ethylenediaminetetraacetic acid (EDTA) on the microhardness, flexural strength and microstructure of mineral trioxide aggregate (MTA; ProRoot MTA, Dentsply Sirona). METHODS:Forty MTA specimens were divided into four groups: [I] QMi...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2017.08.018
更新日期：2017-11-01 00:00:00
abstract：OBJECTIVES:Secondary caries at the tooth-restoration margins is a primary reason for restoration failure. Cracks at the margins lead to leakage which can trap bacteria, producing acids to cause caries. To date, there has been no report on developing an adhesive resin that has self-healing, antibacterial and remineraliz...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2018.05.009
更新日期：2018-08-01 00:00:00
abstract：OBJECTIVES:The aim of this research was to evaluate the effect of titanium tetrafluoride on dentine permeability in comparison with sodium fluoride and acidulated phosphate fluoride to determine their contribution to acid resistance of dentine. METHODS:Thirty-two dentine discs were prepared from extracted mandibular m...
journal_title：Journal of dentistry
pub_type： 临床试验,杂志文章,随机对照试验
doi：10.1016/s0300-5712(99)00029-9
更新日期：1999-09-01 00:00:00
abstract：OBJECTIVES:The goal of this study was to evaluate influence of different shade guides and respective shade matching methods on shade matching results and to analyze user satisfaction with these products and methods. METHODS:Eighty-eight pre-doctoral dental students completed the study. The color of four target shade t...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2009.02.005
更新日期：2009-01-01 00:00:00
abstract：AIM:To evaluate the effect of fluoride iontophoresis on the microtensile bond strength (MTBS) between coronal dentin and two resin-based adhesive systems, and to measure quantitatively dentinal tubule occlusion. METHODS:Twelve freshly extracted intact human mandibular third molars were divided randomly into four group...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2008.04.018
更新日期：2008-09-01 00:00:00
abstract：OBJECTIVE:The aim of this study was to evaluate the effect of sealant placement on the detection of caries by a fluorescent camera (FC), the Spectra caries detector. MATERIALS AND METHODS:In a laboratory study, FC images and readings were obtained from 31 extracted teeth, before and following application of clear seal...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2013.05.005
更新日期：2013-07-01 00:00:00
abstract：AIM:The main goal of this prospective clinical study was to evaluate the outcome of inlay-retained fixed dental prostheses (FDPs) made from heat-pressed lithium-disilicate glass-ceramic. METHODS:Forty-five FDPs were placed in 42 patients (21 women, mean age 36.1 years and 21 men, mean age 42.0 years). The FDPs replace...
journal_title：Journal of dentistry
pub_type： 临床试验,杂志文章
doi：10.1016/j.jdent.2010.07.012
更新日期：2010-11-01 00:00:00
abstract：OBJECTIVES:To measure aspects of fizzy drink consumption in a social environment to inform the development of a laboratory testing regime. METHODS:This was an observational study in which participants were invited to attend one of four pizza and soft drink parties. All such foods and drinks were served in an air condi...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2015.08.008
更新日期：2015-11-01 00:00:00
abstract：:Twenty healthy volunteers entered a study to assess cardiopulmonary responses, as measured by pulse oximetry, following changes in posture in the dental chair and the administration of Diazemuls (diazepam) in doses sufficient to instill sedation (up to a maximum dose of 20 mg) in the volunteers to a degree such that p...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/0300-5712(92)90080-v
更新日期：1992-08-01 00:00:00
abstract：OBJECTIVES:This in vitro study examined the resistance to displacement offered by guide planes and the displacement mechanics of a bilateral bounded saddle cast cobalt chrome alloy removable partial denture framework under conditions simulating an average initial fit. METHODS:A specially designed model mouth jig fitte...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/s0300-5712(01)00016-1
更新日期：2001-05-01 00:00:00
abstract：OBJECTIVES:Methacrylic compounds such as 2-hydroxyethyl methacrylate (HEMA), triethylene glycol dimethacrylate (TEGDMA) and bisphenol A glycerolate (1 glycerol/phenol) dimethacrylate (Bis-GMA) are largely present in auto- or photopolymerizable composite resins. Since the polymerization reaction is never complete, these...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2006.07.008
更新日期：2007-03-01 00:00:00
abstract：OBJECTIVE:Following a successful 2005-2012 phase with three regional practice-based research networks (PBRNs), a single, unified national network called "The National Dental PBRN" was created in 2012 in the United States to improve oral health by conducting practice-based research and serving dental professionals throu...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2013.04.002
更新日期：2013-11-01 00:00:00
abstract：OBJECTIVES:To investigate the potential use of swept-source optical coherence tomography (SS-OCT) as a new tool to evaluate marginal adaptation of composite restorations in class I cavities. METHODS:Round-shaped class I cavities (3mm diameter × 1.5mm depth) were prepared on buccal enamel of bovine teeth with cavity fl...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2011.01.011
更新日期：2011-04-01 00:00:00
abstract：:In the present study Class II resin composite restorations were placed under in vivo and in vitro conditions. For the in vivo part. Class II preparations were cut in teeth destined for extraction for orthodontic reasons. The preparations were completed with the gingival margin in enamel and restored using six differen...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/0300-5712(93)90026-m
更新日期：1993-06-01 00:00:00
abstract：OBJECTIVE:Silver compounds have been used for their medical properties for centuries and in dentistry for more than a century. The aim of this review is to examine the evidence supporting the therapeutic use of silver in dentistry and the outcomes from the clinical trials, as well as mode of action and biocompatibility...
journal_title：Journal of dentistry
pub_type： 杂志文章,评审
doi：10.1016/j.jdent.2012.03.009
更新日期：2012-07-01 00:00:00
abstract：OBJECTIVES:To evaluate the effect of application method on immediate and 6-month resin-dentin microtensile bond strength (microTBS) and nanoleakage (NL) of three one-step self-etch adhesives systems (Clearfil S(3) Bond (S3), Xeno III (XE) and Adper Prompt L-Pop (AD)). METHODS:The oclusal enamel of 30 human molar was r...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2008.09.010
更新日期：2009-01-01 00:00:00
abstract：OBJECTIVES:To evaluate the effect of the addition of epigallocatechin-3-gallate (EGCG) on the antibacterial and physical properties of glass ionomer cement (GIC). METHODS:A conventional GIC, Fuji IX, was used as a control. EGCG was incorporated into GIC at 0.1% (w/w) and used as the experimental group. Chlorhexidine (...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2013.07.014
更新日期：2013-10-01 00:00:00
abstract：OBJECTIVES:To investigate the effectiveness of an indicator gel in revealing exposed dentine. METHODS:Teeth prepared into dentine and then stained with the indicator gel were sectioned for histological examination. RESULTS:The indicator gel was found to stain dentine and thin layers of enamel. CONCLUSION:The gel is ...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/0300-5712(94)00010-d
更新日期：1995-12-01 00:00:00
abstract：OBJECTIVES:Host modifying factors, such as genetic predisposition, may increase severity of periodontitis. Genetic polymorphisms in interleukin-4 (IL-4) genes seem to influence host response to microbial challenge. Two IL-4 polymorphisms were found in association with asthma and atopy, and later with aggressive periodo...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2003.11.004
更新日期：2004-03-01 00:00:00
abstract：:The bacteriological contamination of pumice slurry in polishing units in a dental clinical area (high risk), a production laboratory (medium risk), and a non-clinical teaching laboratory (low risk), was investigated. Slurry samples taken from all three areas were found to be heavily contaminated with pathogenic organi...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/0300-5712(90)90030-i
更新日期：1990-10-01 00:00:00
abstract：OBJECTIVES:The purpose of this study was to determine the dentine fluoride uptake from three fluoride-containing composites (FluorEver, FluoroCore and Pertac-Hybrid) and to investigate their ability to affect the resistance of dentine to an artificial caries challenge. METHODS:Three dentine slabs were prepared from ea...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/s0300-5712(96)00045-0
更新日期：1997-05-01 00:00:00
abstract：OBJECTIVES:To review the established and novel methods of plaque quantification employed in dental research, including a discussion of their merits and to present a new method of planimetrically measuring plaque using light induced fluorescence. METHOD:Quantitative light-fluorescence (QLF) images were acquired from th...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2004.10.017
更新日期：2005-03-01 00:00:00
abstract：OBJECTIVES:The objective of this study was to assess the clinical performance of a direct placement gallium alloy sealed with an established dentine adhesive system. In addition, microanalysis of a few gallium restorations that failed in clinical service was performed. Clinical factors such as pulpal sensitivity, fract...
journal_title：Journal of dentistry
pub_type： 临床试验,杂志文章,随机对照试验
doi：10.1016/s0300-5712(99)00051-2
更新日期：2000-02-01 00:00:00
abstract：PURPOSE:This study determined the shear bond strength of a nanohybrid composite resin to bleached enamel immediately or 15 days later using different adhesive systems and laser application. METHODS:One hundred and forty enamel specimens were prepared from human molar teeth and bleached either with 16% carbamide peroxi...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2009.03.012
更新日期：2009-07-01 00:00:00
abstract：OBJECTIVES:Following tooth pulp exposure, pulpal repair is accomplished by dentine bridge secretion by odontoblast-like cells. However, little information is available about the hierarchy of variables, which influence odontoblast-like cell numbers. The purpose of this study was to examine correlations between pulp capp...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/s0300-5712(02)00024-6
更新日期：2002-09-01 00:00:00
abstract：OBJECTIVES:To determine the perceptibility and acceptability of tooth color differences using computer-generated pairs of teeth with simulated gingival displayed on a calibrated color monitor using appropriate signal detection theory methodology (SDT). METHODS:Twelve dental professionals (four from each of the followi...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2007.03.006
更新日期：2007-07-01 00:00:00
abstract：OBJECTIVE:To evaluate a novel methodology using industrial scanners as a reference, and assess in vivo accuracy of 3 intraoral scanners (IOS) and conventional impressions. Further, to evaluate IOS precision in vivo. METHODS:Four reference-bodies were bonded to the buccal surfaces of upper premolars and incisors in fiv...
journal_title：Journal of dentistry
pub_type： 杂志文章
doi：10.1016/j.jdent.2017.12.006
更新日期：2018-02-01 00:00:00
