Influence of filler geometry and viscosity of composite luting materials on marginal adhesive gap width and occlusal surface height of all-ceramic partial crowns

2021 ◽  
Author(s):  
Sebastian Soliman ◽  
Carolin Casel ◽  
Ralf Krug ◽  
Gabriel Krastl ◽  
Britta Hahn
Keyword(s):  
Occlusal Surface ◽  
All Ceramic ◽  
Gap Width

Fracture of Porcelain-veneered Structures in Fatigue

2007 ◽  
Vol 86 (2) ◽  
pp. 142-146 ◽  
Author(s):  
B. Kim ◽  
Y. Zhang ◽  
M. Pines ◽  
V.P. Thompson
Keyword(s):  
Tungsten Carbide ◽  
Cyclic Load ◽  
Surface Damage ◽  
Lower Surface ◽  
Occlusal Surface ◽  
High Modulus ◽  
Radial Fracture ◽  
Silver Alloy ◽  
All Ceramic ◽  
Palladium Silver

Porcelain-veneered crowns are widely used in modern dentistry, and their fracture remains problematic, especially in all-ceramic systems. We hypothesized that substructure properties have a significant effect on the longevity of porcelain-veneered crowns. Flat porcelain/metal or porcelain/ceramic structures were cemented to dentin-like composite, and a mouth-motion cyclic load of 200 N was delivered by means of a tungsten carbide spherical indenter ( r = 3.18 mm), emulating occlusal loading on crowns supported by dentin. Findings indicated that porcelain on a low-hardness gold-infiltrated alloy was vulnerable to both occlusal surface contact damage and porcelain lower surface radial fracture, while porcelain on a higher-hardness palladium-silver alloy fractured chiefly from occlusal surface damage. The advantage of a high-modulus metal substructure was less pronounced. Fracture in the porcelain/zirconia system was limited to surface damage in the veneer layer, similar to that in the porcelain/palladium-silver system. Bulk fracture, observed in veneered alumina layers, was not found for zirconia.

Fracture behavior, marginal gap width, and marginal quality of vented or pre-cemented CAD/CAM all-ceramic crowns luted on Y-TZP implants

2017 ◽  
Vol 29 (2) ◽  
pp. 175-184 ◽  
Author(s):  
Lucia K. Zaugg ◽  
Simon Meyer ◽  
Nadja Rohr ◽  
Isabella Zehnder ◽  
Nicola U. Zitzmann
Keyword(s):  
Fracture Behavior ◽  
Marginal Gap ◽  
All Ceramic ◽  
Cad Cam ◽  
Ceramic Crowns ◽  
Gap Width

HREM interface studies in SiC-whisker-reinforced Al2O3 and Si3N4 ceramics

1988 ◽  
Vol 46 ◽  
pp. 734-735
Author(s):  
W. Braue ◽  
R.W. Carpenter ◽  
D.J. Smith
Keyword(s):  
Analytical Data ◽  
Base Material ◽  
High Strength ◽  
Ceramic Composites ◽  
Good Thermal Stability ◽  
All Ceramic ◽  
Sic Whiskers ◽  
Base Composite ◽  
C 30 ◽  
Si3n4 Ceramics

Whisker and fiber reinforcement has been established as an effective toughening concept for monolithic structural ceramics to overcome limited fracture toughness and brittleness. SiC whiskers in particular combine both high strength and elastic moduli with good thermal stability and are compatible with most oxide and nonoxide matrices. As the major toughening mechanisms - crack branching, deflection and bridging - in SiC whiskenreinforced Al2O3 and Si3N41 are critically dependent on interface properties, a detailed TEM investigation was conducted on whisker/matrix interfaces in these all-ceramic- composites.In this study we present HREM images obtained at 400 kV from β-SiC/α-Al2O3 and β-SiC/β-Si3N4 interfaces, as well as preliminary analytical data. The Al2O3- base composite was hotpressed at 1830 °C/60 MPa in vacuum and the Si3N4-base material at 1725 °C/30 MPa in argon atmosphere, respectively, adding a total of 6 vt.% (Y2O3 + Al2O3) to the latter to promote densification.

Biomimetic materials: An introduction

1992 ◽  
Vol 50 (2) ◽  
pp. 1020-1021 ◽  
Author(s):  
M. Sarikaya ◽  
J. T. Staley ◽  
I. A. Aksay
Keyword(s):  
Self Assembly ◽  
Structural Control ◽  
Hierarchical Structures ◽  
Ceramic Composites ◽  
Advanced Materials ◽  
Length Scale ◽  
Spider Webs ◽  
Biomimetic Materials ◽  
Synthetic Materials ◽  
All Ceramic

Biomimetics is an area of research in which the analysis of structures and functions of natural materials provide a source of inspiration for design and processing concepts for novel synthetic materials. Through biomimetics, it may be possible to establish structural control on a continuous length scale, resulting in superior structures able to withstand the requirements placed upon advanced materials. It is well recognized that biological systems efficiently produce complex and hierarchical structures on the molecular, micrometer, and macro scales with unique properties, and with greater structural control than is possible with synthetic materials. The dynamism of these systems allows the collection and transport of constituents; the nucleation, configuration, and growth of new structures by self-assembly; and the repair and replacement of old and damaged components. These materials include all-organic components such as spider webs and insect cuticles (Fig. 1); inorganic-organic composites, such as seashells (Fig. 2) and bones; all-ceramic composites, such as sea urchin teeth, spines, and other skeletal units (Fig. 3); and inorganic ultrafine magnetic and semiconducting particles produced by bacteria and algae, respectively (Fig. 4).

Replacement of Congenitally Missing Bilateral Maxillary Canines with Dental Implants: A Rare Case Report and Mini Review

2019 ◽  
Vol 13 (1) ◽  
pp. 371-376
Author(s):  
Abduljabbar Mohammed Alsameai ◽  
Basema Abdullah Khabaz ◽  
Mohammed Abdo Alraawi ◽  
Mohammed M Al Moaleem
Keyword(s):  
Case Report ◽  
Treatment Plan ◽  
Young Female ◽  
Normal Function ◽  
Short Term Result ◽  
Osseointegrated Implants ◽  
All Ceramic ◽  
Rare Case Report ◽  
Ceramic Crowns ◽  
Congenitally Missing

Introduction: Maxillary canines play strategic roles in maintaining the normal function and visibility of teeth. However, rare cases of bilateral permanent congenitally missing maxillary canines were occurring. Replacing these missing canines with dental implant prostheses is an optimal treatment plan for aesthetics and functions. Case Report: In this case report, we described the replacement of bilateral maxillary canines with osseointegrated implants to support all-ceramic prostheses for a young female patient. This treatment avoids the conventional preparation of adjacent teeth as a part of prosthetic reconstructions. In addition to that, all-ceramic crowns are biocompatible with oral cavity structures. Conclusion: The stable short-term result has been achieved with the replacement of the bilateral congenitally missed canines with an implant and cemented all-ceramic crowns, with 3-years cumulative success rate.

scholarly journals Influence of Eccentricity and Angular Velocity on Force Effects on Rotor of Magnetorheological Damper

2018 ◽  
Vol 180 ◽  
pp. 02091
Author(s):  
Dominik Šedivý ◽  
Petr Ferfecki ◽  
Simona Fialová
Keyword(s):  
Magnetic Induction ◽  
Magnetorheological Damper ◽  
Squeeze Film ◽  
Fluid Viscosity ◽  
Squeeze Film Damper ◽  
Viscous Forces ◽  
Angular Velocities ◽  
Volume Method ◽  
Gap Width ◽  
Made In

This article presents the evaluation of force effects on squeeze film damper rotor. The rotor is placed eccentrically and its motion is translate-circular. The amplitude of rotor motion is smaller than its initial eccentricity. The force effects are calculated from pressure and viscous forces which were measured by using computational modeling. Damper was filled with magnetorheological fluid. Viscosity of this non-Newtonian fluid is given using Bingham rheology model. Yield stress is not constant and it is a function of magnetic induction which is described by many variables. The most important variables of magnetic induction are electric current and gap width between rotor and stator. The simulations were made in finite volume method based solver. The motion of the inner ring of squeeze film damper was carried out by dynamic mesh. Numerical solution was solved for five different initial eccentricities and angular velocities of rotor motion.

scholarly journals New Method for Analysis of the Temporomandibular Joint Using Cone Beam Computed Tomography

Sensors ◽  
2021 ◽  
Vol 21 (9) ◽  
pp. 3070
Author(s):  
Sebastian Iwaszenko ◽  
Jakub Munk ◽  
Stefan Baron ◽  
Adam Smoliński
Keyword(s):  
Computed Tomography ◽  
Temporomandibular Joint ◽  
Cross Section ◽  
Cone Beam Computed Tomography ◽  
Cone Beam ◽  
Section Plane ◽  
New Approach ◽  
Volume Of Interest ◽  
Gap Width

Modern dentistry commonly uses a variety of imaging methods to support diagnosis and treatment. Among them, cone beam computed tomography (CBCT) is particularly useful in presenting head structures, such as the temporomandibular joint (TMJ). The determination of the morphology of the joint is an important part of the diagnosis as well as the monitoring of the treatment results. It can be accomplished by measurement of the TMJ gap width at three selected places, taken at a specific cross-section. This study presents a new approach to these measurements. First, the CBCT images are denoised using curvilinear methods, and the volume of interest is determined. Then, the orientation of the vertical cross-section plane is computed based on segmented axial sections of the TMJ head. Finally, the cross-section plane is used to determine the standardized locations, at which the width of the gap between condyle and fossa is measured. The elaborated method was tested on selected TMJ CBCT scans with satisfactory results. The proposed solution lays the basis for the development of an autonomous method of TMJ index identification.

Sign in / Sign up

Export Citation Format

Share Document