80 results match your criteria martens hardness


Characterization of Methacrylate-Based Resins Containing Methacryl-Polyhedral Oligomeric Silsesquioxanes (MA-POSS-8).

Materials (Basel) 2021 Mar 29;14(7). Epub 2021 Mar 29.

Department of Preventive Dentistry, Periodontology and Cariology, University Medical Center Göttingen, 37075 Göttingen, Germany.

The use of functionalized dental adhesives that might prevent degradation of the dentin hybrid layer has been proposed. The aim of the study was to characterize the physicochemical properties and the potential to induce mineral precipitation of methacrylate-based resins containing methacryl-functionalized polyhedral oligomeric silsesquioxane (MA-POSS-8). In total, six different compositions of resins based on bisphenol A glycerolate dimethacrylate (BisGMA, 40 to 60 wt. Read More

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Modern CAD/CAM silicate ceramics, their translucency level and impact of hydrothermal aging on translucency, Martens hardness, biaxial flexural strength and their reliability.

J Mech Behav Biomed Mater 2021 Mar 13;118:104456. Epub 2021 Mar 13.

Department of Prosthetic Dentistry, LMU Munich, Munich, Germany.

Objectives: To investigate the impact of hydrothermal aging on Martens parameter (Martens hardness: HM/elastic indentation modulus: E) and biaxial flexural strength (BFS) of recently available CAD/CAM silicate ceramics.

Methods: 220 specimens (diameter: 12 mm, thickness: 0.95 mm) were fabricated from six CAD/CAM ceramics in two translucency levels (LT/HT): (a) two lithium disilicate (Amber Mill, ABM; IPS e. Read More

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New method to differentiate surface damping behavior and stress absorption capacities of common CAD/CAM restorative materials.

Dent Mater 2021 04 30;37(4):e213-e230. Epub 2021 Jan 30.

Department of Prosthodontics, Justus-Liebig University, Schlangenzahl 14, 35392 Giessen, Germany. Electronic address:

Objectives: To assess energy dissipation capacities and surface damping abilities of different CAD/CAM restorative materials (CRMs) to characterize stress resistance during load peaks.

Methods: Using instrumented indentation testing (IIT), Martens hardness (HM) together with its elastic (η) and plastic index (η) and Leeb hardness (HLD) together with its deduced energy dissipation (HLD) were determined for eight ceramic, eight composite, and four polymer-based materials as well as three metals. The results were compared to those of bovine enamel. Read More

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Mapping of the Micro-Mechanical Properties of Human Root Dentin by Means of Microindentation.

Materials (Basel) 2021 Jan 21;14(3). Epub 2021 Jan 21.

Clinic of Operative and Pediatric Dentistry, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, 01307 Dresden, Germany.

The extensive knowledge of root dentin's mechanical properties is necessary for the prediction of microstructural alterations and the teeth's deformations as well as their fracture behavior. Standardized microindentation tests were applied to apical, medial, and cervical root sections of a mandibular human first molar to determine the spatial distribution of the hard tissue's properties (indentation modulus, indentation hardness, Martens hardness, indentation creep). Using an indentation mapping approach, the inhomogeneity of mechanical properties in longitudinal as well as in transversal directions were measured. Read More

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January 2021

Correlation of the mechanical and biological response in light-cured RBCs to receiving a range of radiant exposures: Effect of violet light.

J Dent 2021 02 29;105:103568. Epub 2020 Dec 29.

Department of Dental Clinical Sciences, Faculty of Dentistry, Dalhousie University, Halifax, Nova Scotia, Canada.

Objective: This study correlates the mechanical and biological response of commercially available resin-based composites (RBCs) to clinically relevant light-curing conditions.

Methods: Two RBCs (Venus and Venus Pearl; Kulzer) that use different monomer and photo-initiator systems, but have a similar filler volume and shade, were exposed to either just blue light, or violet and blue light from two different LCUs (Translux Wave and Translux 2Wave; Kulzer). Distance and exposure times were adjusted so that both LCUs delivered 5 similar levels of radiant exposures (RE) between 1. Read More

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February 2021

Impact of polymerization and storage on the degree of conversion and mechanical properties of veneering resin composites.

Dent Mater J 2021 Mar 18;40(2):487-497. Epub 2020 Dec 18.

Department of Prosthetic Dentistry, University Hospital, LMU Munich.

To investigate the degree of conversion (DC), Martens hardness (HM), elastic indentation modulus (E), and flexural strength (FS) of veneering resin composites (SR Nexco Paste (NP), Ceramage Incisal (CI), Gradia Plus (GP); n=60/group) cured with different polymerization devices (bre.Lux Power Unit, Labolight DUO, Otoflash G171, LC-3DPrint Box, PCU LED; n=12/subgroup) after storage. Otoflash G171 and Labolight DUO showed increased DC/HM/E. Read More

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Influence of Different Postpolymerization Strategies and Artificial Aging on Hardness of 3D-Printed Resin Materials: An In Vitro Study.

Int J Prosthodont 2020 Nov/Dec;33(6):634-640

Purpose: To investigate the influence of different postpolymerization strategies and artificial aging periods on the Martens hardness parameters of 3D-printed resin materials indicated for temporary use.

Materials And Methods: Disks made of four 3D-printed resin materials (n = 30 each) were additively manufactured and postpolymerized with three different postpolymerization devices (n = 10 specimens of each material per device). Disks cut from a prefabricated milling material served as a control. Read More

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December 2020

Evaluation of translucency, Marten's hardness, biaxial flexural strength and fracture toughness of 3Y-TZP, 4Y-TZP and 5Y-TZP materials.

Dent Mater 2021 02 29;37(2):212-222. Epub 2020 Nov 29.

Dental Material Unit, Department of Prosthetic Dentistry, University Hospital, Ludwig-Maximilians-University, Goethestrasse 70, 80336 Munich, Germany. Electronic address:

Objectives: Testing and comparing of different non-shaded zirconia materials (3Y-TZP, 4Y-TZP and 5Y-TZP) on optical and mechanical properties.

Materials And Methods: Zirconia materials (N = 320, Opaque O, Translucent T, Extra Translucent ET, High Translucent HT) were investigated on translucency, Martens parameter, biaxial flexural strength, Chevron-Notch-Beam (CNB) fracture toughness (K) and grain size. The grain size was analyzed using a scanning electron microcopy (SEM). Read More

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February 2021

Mechanical and optical properties of indirect veneering resin composites after different aging regimes.

Dent Mater J 2021 Mar 19;40(2):279-287. Epub 2020 Nov 19.

Department of Prosthetic Dentistry, University Hospital.

This study tested and compared properties of six modern indirect veneering resin composites (VRC), namely Ceramage (Shofu), dialog Vario (Schütz Dental), Gradia Plus (GC Europe), in:joy (Dentsply), Signum composite (Heraeus Kulzer), and SR Nexco (Ivoclar Vivadent). Specimens were fabricated from dentin and enamel pastes and following properties were analyzed: (1) two-body wear (TB), (2) surface roughness (SR), (3) Martens hardness parameters (HM and E), and (4) translucency (T). The highest impact on HM and E was exerted by VRC brand (HM: η=0. Read More

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Comparison of mechanical properties of different reinforced glass-ceramics.

J Prosthet Dent 2020 Nov 6. Epub 2020 Nov 6.

Head of Dental Material Research, Department of Prosthetic Dentistry, University Hospital, LMU Munich, Munich, Germany.

Statement Of Problem: Data concerning the mechanical properties of the newly developed lithium disilicate ceramic HS10PC are lacking.

Purpose: The purpose of this in vitro study was to investigate the flexural strength (FS), Martens hardness (HM), indentation modulus (E), fracture load (FL), and wear resistance (WR) of HS10PC compared with those of the established glass-ceramics IPS e.max Press and IPS Empress Esthetic. Read More

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November 2020

Spatial Distribution of the Micro-Mechanical Properties in High-Translucent CAD/CAM Resin-Composite Blocks.

Authors:
Nicoleta Ilie

Materials (Basel) 2020 Jul 28;13(15). Epub 2020 Jul 28.

Department of Conservative Dentistry and Periodontology, University Hospital, LMU Munich, Goethestr. 70, D-80336 Munich, Germany.

Industrially cured, high-translucent computer-aided design/computer-aided manufacturing (CAD/CAM) resin-based composites (RBC) are the most recently launched dental restoratives. Clinical treatments and laboratory tests are based on a homogeneous distribution of properties within CAD/CAM blocks to obtain constant and reproducible results. The study therefore aims to determine the spatial distribution of various micro-mechanical parameters (Vickers hardness, Martens hardness, indentation modulus, creep, elastic and total indentation work) in five representative CAD/CAM RBCs. Read More

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A critical evaluation of the material properties and clinical suitability of in-house printed and commercial tooth replicas for endodontic training.

Int Endod J 2020 Oct 24;53(10):1446-1454. Epub 2020 Jul 24.

Department of Conservative Dentistry, University Hospital, Julius-Maximilians-University, Würzburg, Germany.

Aim: To assess the suitability of several 3D-printed resins for the manufacturing of tooth replicas for endodontic training in comparison with commercially available replicas by analysing the properties of the materials and comparing them with real teeth during endodontic training.

Methodology: Tooth replicas were 3D-printed using four resins (NextDent Model, NextDent C&B, V-Print ee and Vero White Plus) and compared with two commercially available products (VDW and Smile Factory) as well as extracted human teeth. Martens hardness, indentation modulus and radiopacity were investigated on these tooth replicas. Read More

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October 2020

In vitro study on the influence of postpolymerization and aging on the Martens parameters of 3D-printed occlusal devices.

J Prosthet Dent 2020 May 19. Epub 2020 May 19.

Professor, Department of Prosthetic Dentistry, University Hospital, LMU Munich, Munich, Germany.

Statement Of Problem: Additive manufacturing has been proposed for the fabrication of occlusal devices. However, information about the mechanical properties of additively manufactured devices is lacking.

Purpose: The purpose of this in vitro study was to evaluate the influence of the postpolymerization unit and artificial aging on the Martens hardness (HM) and indentation modulus (E) of different 3D-printed materials in comparison with a conventionally milled material. Read More

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Translucency, flexural strength, fracture toughness, fracture load of 3-unit FDPs, Martens hardness parameter and grain size of 3Y-TZP materials.

Dent Mater 2020 07 4;36(7):838-845. Epub 2020 May 4.

Department of Prosthetic Dentistry, University Hospital, LMU Munich, Goethestrasse 70, 80336 Munich, Germany. Electronic address:

Objective: This investigation tested pre-shaded 3Y-TZP materials on optical, mechanical and structural properties and calculated correlations between these properties.

Methods: Seven A2-shaded 3Y-TZP zirconia materials were investigated on translucency (T) via UV-vis-spectrophotometer, fracture load of 3-unit FDPs (FL), biaxial flexural strength (FS), Chevron-Notch Beam (CNB), fracture toughness (K) and Martens parameter (hardness: HM and indentation modulus: E). FL, FS and K were measured in a universal testing machine. Read More

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Consolidation of Fir Wood by Poly(vinyl butyral--vinyl alcohol--vinyl acetate) Treatment: Study of Surface and Mechanical Characteristics.

Polymers (Basel) 2020 May 2;12(5). Epub 2020 May 2.

Dpto. Ciencia e Ingeniería de Materiales e Ingeniería Química, IQMAAB, Universidad Carlos III de Madrid Avda. Universidad, 15, 28911 Leganés, Madrid, Spain.

The ability of poly(vinyl butyral--vinyl alcohol--vinyl acetate) (PVBVA) to consolidate Fir wood was studied in terms of the surface and mechanical properties' changes. Two variables were considered to treat the wood: (i) the concentration (5 and 10 wt.%) of PVBVA solutions and (ii) the method of application (brushing and immersion). Read More

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Impact of artificial aging by thermocycling on edge chipping resistance and Martens hardness of different dental CAD-CAM restorative materials.

J Prosthet Dent 2021 Feb 27;125(2):326-333. Epub 2020 Feb 27.

Scientific Head, Dental Material Unit, Department of Prosthodontics, Ludwig-Maximilians University, Munich, Germany.

Statement Of Problem: The selection of an appropriate restorative material based on fracture behavior is important for the marginal integrity of a dental restoration. For computer-aided design and computer-aided manufacturing (CAD-CAM) restorative materials, information regarding their edge chipping resistance is scarce.

Purpose: The purpose of this in vitro study was to determine the edge chipping resistance (ECR) and Martens hardness (HM) of 6 different dental CAD-CAM restorative materials before and after thermocycling. Read More

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February 2021

Suitability of the new Aryl-Ketone-Polymer indicated for removable partial dentures: Analysis of elastic properties and bond strength to denture resin.

Dent Mater J 2020 Aug 21;39(4):539-546. Epub 2020 Feb 21.

Department of Prosthetic Dentistry, University Hospital, Ludwig-Maximilians-University Munich.

Elastic properties of Aryl-Ketone-Polymer (UAKP) and tensile bond strength (TBS) to denture resin (PalaXpress) were tested. Indentation modulus (E) and indentation hardness (H) were measured via Martens hardness (n=10 specimens) with 4.2±0. Read More

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Flexural strength, fracture toughness, three-body wear, and Martens parameters of pressable lithium-X-silicate ceramics.

Dent Mater 2020 03 30;36(3):420-430. Epub 2020 Jan 30.

Department of Prosthetic Dentistry, University Hospital, LMU Munich, 80336 Munich, Germany.

Objectives: To test and compare five pressable lithium-X-silicate-ceramics on their mechanical and wear properties.

Methods: Specimens were pressed and prepared from: i. Amber Press (AP), ii. Read More

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Does photodynamic therapy with methylene blue affect the mechanical properties and bond strength of glass-fiber posts in different thirds of intraradicular dentin?

Photodiagnosis Photodyn Ther 2020 Jun 24;30:101673. Epub 2020 Jan 24.

Department of Restorative Dentistry, Discipline of Endodontics, Araçatuba School of Dentistry, São Paulo State University - UNESP, Araçatuba, SP, Brazil. Electronic address:

Background: There are few studies on the influence of methylene blue as a photosensitiser on the mechanical properties and adhesion of glass-fiber posts to intraradicular dentin. Thus, this in vitro study aimed to evaluate the influence of photodynamic therapy with a methylene blue photosensitizer on the Martens hardness, elastic modulus, and bond strength of glass-fiber posts in different thirds of intraradicular dentin.

Methods: Eighty bovine teeth were divided into the following five groups: a control using deionized water, and four other groups according to the methylene blue concentration (50 mg/L or 100 mg/L) and substrate treatment (with or without red laser action). Read More

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Comparing the mechanical properties of pressed, milled, and 3D-printed resins for occlusal devices.

J Prosthet Dent 2020 Dec 17;124(6):780-786. Epub 2020 Jan 17.

Research Associate, Department of Reconstructive Dentistry, University Center for Dental Medicine, University of Basel, Basel, Switzerland. Electronic address:

Statement Of Problem: Comparisons of the material qualities of pressed, milled, and 3D-printed occlusal devices are sparse, complicating informed decisions on material choice.

Purpose: The purpose of this in vitro study was to compare the material properties of pressed, milled, and 3D-printed resins, as well as how these are affected by thermal aging. These data were then used to estimate the likely clinical performance of the tested materials. Read More

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December 2020

Effect of glass fiber post customization on the mechanical properties of resin cement and underlying dentin.

Gen Dent 2020 Jan-Feb;68(1):72-77

This study evaluated the Martens hardness (HM) and elastic modulus (E) of resin cement and dentin underlying the bonding interface of customized glass fiber posts luted to intraradicular dentin and subjected to mechanical cycling. Two null hypotheses were tested: (1) no differences in the mechanical properties (HM and E) of the resin cement and underlying dentin would be found between customized and noncustomized glass fiber post groups, with or without mechanical cycling; and (2) no differences in the mechanical properties of the resin cement or underlying dentin would be found between the cervical, middle, and apical thirds of the intraradicular dentin. Forty single-rooted premolars were divided into 4 groups: customized or noncustomized glass fiber post, with or without mechanical cycling. Read More

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January 2020

The effects of vıtal dyes on mechanıcal propertıes of the human anterıor lens capsule.

Indian J Ophthalmol 2020 01;68(1):66-70

Department of Ophthalmology, Health Sciences University Van Education and Training Hospital, Van, Turkey.

Purpose: The purpose of this study was to evaluate the mechanical effects of vital dyes on the anterior lens capsule via the nanoindentation method.

Methods: Twenty anterior lens capsules of 20 different patients were dissected into four equal fragments. Each fragment was stained separately with dyes for intraocular surgeries, such as trypan blue 0. Read More

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January 2020

Comparison of various 3D printed and milled PAEK materials: Effect of printing direction and artificial aging on Martens parameters.

Dent Mater 2020 02 27;36(2):197-209. Epub 2019 Nov 27.

Department of Prosthetic Dentistry, LMU Munich, Goethestrasse 70, Munich, 80336, Germany.

Objectives: The aim of this study was to investigate the effect of artificial aging on the Martens parameters of different 3D printed and milled polyaryletherketon (PAEK) materials.

Methods: In total 120 specimens of 4 different polyetheretherketon (PEEK) materials (Essentium PEEK, KetaSpire PEEK MS-NT1, VICTREX PEEK 450G and VESTAKEEP i4 G) were additively manufactured via fused layer manufacturing (FLM) in either horizontal or vertical directions (n=15 per group). 75 specimens were milled out of prefabricated PAEK blanks from the materials breCAM. Read More

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February 2020

A Comparison of the Compositional, Microstructural, and Mechanical Characteristics of Ni-Free and Conventional Stainless Steel Orthodontic Wires.

Materials (Basel) 2019 Oct 19;12(20). Epub 2019 Oct 19.

Clinic of Orthodontics and Pediatric Dentistry, Center of Dental Medicine, Faculty of Medicine, University of Zurich, 8032 Zurich, Switzerland.

Ni-free orthodontic wires were introduced to mitigate concerns associated with the use of Ni-containing alloys in orthodontics. However, limited information is available on their properties and therefore, the aim of this study was to characterize the elemental composition, the microstructure, and the mechanical properties of Ni-free orthodontic wires and compare them with their stainless steel (SS) counterparts. Four Ni-free and four conventional SS wires were included in this study. Read More

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October 2019

Surface, Microstructural, and Mechanical Characterization of Prefabricated Pediatric Zirconia Crowns.

Materials (Basel) 2019 Oct 9;12(20). Epub 2019 Oct 9.

Clinic of Orthodontics and Pediatric Dentistry, Centrer of Dental Medicine, University of Zurich, 8032 Zurich, Switzerland.

The purpose of this study was to characterize the surface roughness, the microstructure, and mechanical properties of four prefabricated zirconia pediatric crowns. Ten prefabricated crowns from four different manufacturers (Cheng Crowns Zirconia), (EZCrowns), (NuSmile ZR), and (Zirconia Pediatric Crowns) were included in this study. The surface roughness parameters (Sa, Sq, Sz, Sc, and Sv) of all samples were studied by optical profilometry and then the microstructure was studied by Raman spectroscopy. Read More

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October 2019

The effect of different cooling procedures on mechanical properties of denture base materials measured by instrumented indentation testing.

J Prosthodont Res 2020 Jul 30;64(3):326-331. Epub 2019 Sep 30.

Department of Biomaterials, School of Dentistry, National and Kapodistrian University of Athens, Greece.

Purpose: To evaluate the different cooling procedures on the mechanical properties of five heat-cured polymethyl methacrylate (PMMA) denture materials.

Methods: 250 specimens were made equally from Meliodent (ME), Paladon 65 (PA), Probase Hot (PB), Stellon QC-20 (QC) and Vertex Rapid Simplified (VE) implementing five different cooling procedures (n=10/procedure): A) removal from water bath, bench-cooling (10min) and cooling under water (15min), B) remain in water bath till room temperature, C) removal from water bath and cooling in water for 15min, D) removal from water bath and bench cooling till room temperature and E) removal from water bath, bench cooling for 30min and cooling under water for 15min. The specimens were immersed in distilled water (15 days/37ºC) and then subjected to Instrumented Indentation Testing for Martens Hardness (HM), indentation modulus (E) and elastic index (η). Read More

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Water-induced Effects on the Hardness and Modulus of Contemporary Sealants Derived from Instrumented Indentation Testing (IIT).

J Contemp Dent Pract 2019 Jun 1;20(6):653-656. Epub 2019 Jun 1.

Clinic of Orthodontics and Pediatric Dentistry, Center of Dental Medicine, University of Zurich, Zuirch, Switzerland, Phone: +41 446343210, e-mail:

Aim: To compare the mechanical properties of four different types of contemporary fissure sealants before and after water storage employing a modern instrumented indentation testing (IIT) method.

Materials And Methods: Four different types of materials used in everyday practice were deliberately selected. Fissurit (FIS) is a highly filled resin, Embrace (EMB) is a bisphenol A (BPA)-free unfilled resin, Helioseal (HEL) is an unfilled resin, and Riva Protect (RIV) is a glass-ionomer material. Read More

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Changes in Roughness and Mechanical Properties of Invisalign Appliances after One- and Two-Weeks Use.

Materials (Basel) 2019 Jul 28;12(15). Epub 2019 Jul 28.

Clinic of Orthodontics and Pediatric Dentistry, Center of Dental Medicine, University of Zurich, 8032 Zurich, Switzerland.

The aim of this study was to estimate the possible changes of surface roughness and the mechanical properties of Invisalign appliances over one- and two-week of service. Forty appliances with attachments were retrieved after the end of orthodontic treatment from different patients. Half of them had been used for one week (1W), and the rest for two weeks (2W). Read More

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Effects of dentifrices on mechanical resistance of dentin and restorative materials after erosion and abrasion.

J Mech Behav Biomed Mater 2019 09 4;97:7-12. Epub 2019 May 4.

Department of Restorative Dentistry, São Paulo State University (Unesp), School of Dentistry, Araçatuba. R. José Bonifácio 1193, CEP, 16015-050, Araçatuba/SP, Brazil. Electronic address:

The aim of this study was to evaluate the mechanical resistance of dentin and restorative materials submitted to erosive/abrasive challenges with different dentifrices. The dentin was restored using a resin-modified glass-ionomer (RMGIC) or a composite resin (RC). One hemiface of the sample was protected, and the other was subdivided according to the applied dentifrice (n = 10): without fluoride (SF), sodium fluoride (NaF) and stannous fluoride (SnF). Read More

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September 2019

A study of the mechanical properties of as-received and intraorally exposed single-crystal and polycrystalline orthodontic ceramic brackets.

Eur J Orthod 2020 Jan;42(1):72-77

Clinic of Orthodontics and Pediatric Dentistry, Center of Dental Medicine, University of Zurich, Switzerland.

Background: Although ceramic brackets have been extensively used for decades in orthodontics there is not till today any study focusing on the possible deterioration of mechanical properties after in vivo ageing.

Objectives: To determine whether the mechanical properties of alumina orthodontic brackets change after intraoral ageing thereby assessing the validity of a theoretical model established for the performance of ceramics in wet environments.

Materials And Methods: Two alumina brackets, one single crystal (Radiance, American Orthodontics, Sheboygan, WI) and one polycrystalline (Clarity, 3M, St. Read More

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January 2020