objectives : marginal adaptation is important for long-term success of full-coverage restorations. the aim of this study was to determine the effect of porcelain firing cycle and different thicknesses of ips e.max core on marginal accuracy of all-ceramic restorations. materials and methods : a standard stainless steel die with 0.8 mm classic chamfer finish line and 10° taper was used in this in...

Background: Our research aimed to compare the biaxial flexural strength of glass ceramic and two different monolithic zirconias after aging, examine fracture surfaces with scanning electron microscopy (SEM) perform elemental analysis energy dispersive spectroscopy (EDS). Methods: Two types CAD/CAM materials (Katana UTML Prettau Anterior) a lithium disilicate material (IPS emax Press) were selec...

Background and Aim: One of the problems of all ceramic restorations is their risk of fracture due to occlusal loads. The aim of the present study was to compare the effect of two marginal designs (shoulder and chamfer) on the fracture resistance of IPS-emax all ceramic restorations. Materials and Methods: One extracted maxillary first premolar received chamfer 50' marginal preparation (0.8 m...

BACKGROUND The field of dental ceramics for CAD-CAM is enriched with a new innovative material composition having a porous three-dimensional structure of feldspathic ceramic infiltrated with acrylic resins.The aim of this study is to determine the mechanical properties of Polymer-Infiltrated-Ceramic-Network (PICN) and compare its performance with other ceramics and a nano-ceramic resin availabl...

Background: Marginal adaptation is critical for long – term success of crown and bridge restoration. Computer aided design / computer manufacture (CAD/ CAM) system gaining more importance in the fabrication dental Objective: The aim this study to evaluate effect crystallization firing on vertical marginal gap IPS. emax CAD crowns which fabricated with two different CAD/CAM systems .Materials Me...

abstract   statement of problem: fracture of veneering porcelain has been described as the most frequent reason for the failure of zirconia-based fixed restorations. objectives: the purpose of this study was to evaluate and compare the shear bond strength of a zirconium oxide core material to three commercial veneering ceramics. materials and methods: three types of veneering ceramics were sele...

Objectives: The effect of ceramics construction (pressable, machinable) and corrosion on flexural strength and micro-hardness was studied. Materials & Methods: Two types of ceramics were tested: IPS e-max Press and IPS e-max CAD. Forty samples were constructed and divided into 2 groups according to the type of ceramics. Each group was then subdivided into 2 subgroups. Subgroups 1 were not subje...

Background: To identify and compare the shade variations of various commonly used esthetic dental ceramics by calculating their total-color-difference (ΔE) translucency parameter (TP) using a spectrophotometer. Methods: In total, 165 disc specimens from three shades (A1, B1, C1) five ceramic materials (N = 55/shade; n 11/ceramic material group) were prepared (Metal-ceramic (MC), IPS e.max press...