Background: This study aimed to assess the fracture resistance of zirconia restorations fabricated with rapid layer (RL group) technique and zirconia computer-aided design/computer-aided manufacturing (zir/CAD/CAM) system (ZC group). Methods:This study evaluated 30 all-ceramic crowns in two groups of 15. After fabricating the metal dies and scanning them ...

Introduction: Failures might occur at metal‒porcelain interfaces as a problem with metal‒ceramic restorations even with the application of airborne-particle abrasion technique. This study was undertaken to evaluate the effect of Nd:YAG laser treatment on the bond strength of porcelain fused to metal. Methods:  Twenty-four cylindrical specimens (4 mm in diameter and 4 mm in height) were made of ...

BACKGROUND In recent years there has been an improvement of zirconia ceramic materials to replace posterior missing teeth. To date little in vitro studies has been carried out on the fracture resistance of zirconia veneered posterior fixed dental prostheses. This study investigated the fracture resistance and the failure mode of 3-unit zirconia-based posterior fixed dental prostheses fabricated...

Background: The advantages of the PFM systems are to combine fracture resistance metal substructure with aesthetic property porcelain. present study compared shear bond strength ceramic material veneered zirconia core by layering and pressing techniques.Materials Methods: 50 samples blocks were divided into 2 groups. Each group consisted 25 samples. In I, over technique in II, was used. loaded ...

PURPOSE This in vitro study compared the effect of five different techniques on the surface roughness of feldspathic porcelain. MATERIALS AND METHODS 100 feldspathic porcelain disk samples mounted in acrylic resin blocks were divided into five groups (n=20) according to type of surface treatment: I, hydrofluoric acid (HFA); II, Deglazed surface porcelain treated with Neodymium:yttrium- alumin...

OBJECTIVES This study sought to assess the effect of bracket base design on the shear bond strength (SBS) of the bracket to feldspathic porcelain. MATERIALS AND METHODS This in vitro, experimental study was conducted on 40 porcelain-fused-to-metal restorations and four different bracket base designs were bonded to these specimens. The porcelain surfaces were etched, silanized, and bonded to b...

This in vitro study investigated the influence of using different combinations of bracket, adhesive, and light-curing source on the tensile bond strength to porcelain and on failure patterns at debonding. Tensile tests were performed using: one ceramic bracket versus one metal bracket, two orthodontic composites; type bisphenol A-glycidyldimethacrylate and urethane dimethacrylate (UDMA), and fo...

The widespread use of porcelain in restorative dentistry is generally due to its esthetic appearance even though it is brittle. The transverse strength, or modulus rupture, averages around 108 MPa (16,000 psi) for aluminous porcelain and 88 MPa (13,000 psi) for feldspathic porcelain. The tensile strength, as determined by diametral compression, is approximately 29 MPa (4,200 psi) for opaque fel...