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...

BACKGROUND AND OBJECTIVE The popularity of ceramic restorations can be attributed to its life-like appearance, durability and biocompatibility and therefore ceramic restorations have been widely used for anterior and posterior teeth. Ceramic restorations have esthetic and biocompatible advantages but low fracture resistance. Since it has high flexural strength and fracture resistance, yttria-st...

PURPOSE This study compared the effect of three intraoral repair systems on the bond strength between composite resin and zirconia core. MATERIALS AND METHODS THIRTY ZIRCONIA SPECIMENS WERE DIVIDED INTO THREE GROUPS ACCORDING TO THE REPAIR METHOD: Group I- CoJet™ Repair System (3M ESPE) [chairside silica coating with 30 µm SiO2 + silanization + adhesive]; Group II- Ceramic Repair System (Ivoc...

OBJECTIVE The aim of this study was to determine the effect of trenched zirconia bar on the von Mises stress distribution of IPS -Empress II core ceramics. MATERIALS AND METHODS The three-dimensional model including a three-unit bridge from the second premolar to the second molar was designed. The model was reinforced with zirconia bar (ZB), zirconia bar with vertical trench (VZB) and zirconi...

OBJECTIVE This study tested whether the two-body wear of monolithic zirconia and their corresponding enamel antagonists was higher compared to monolithic alloy and veneered zirconia. MATERIALS AND METHODS Cylindrical specimens (N = 36, n = 6) were prepared out of (A) veneered zirconia (VZ), (B) glazed zirconia using a glaze ceramic (GZC), (C) glazed zirconia using a glaze spray (GZS), (D) man...

Objectives: The aim of this study was to compare the microtensile bond strengths (µ TBS) of three core materials with one lithium disilicate reinforced ceramic using two resin cements. Methods: Three core materials (Nulite F® (Biodental Technologies), Filtek Z250® (3M-ESPE), Prettau-Anterior® (Zirkonzhan, Germany)) were prepared as blocks (10×10×4 mm3) according...

Background and Aim: Bonding of zirconia to resin cement is challenging, and the zirconia surface requires surface treatment to yield an acceptable bond strength. This study aimed to evaluate the effect of different surface treatments on the bond strength of zirconia to a resin cement. Materials and Methods: In this in-vitro experimental study, 60 zirconia discs measuring 12 mm in diameter an...

Objectives: Considering the need for intraoral polishing of zirconia restorations, this in vitro study aimed to 1) evaluate 2D and 3D surface roughness different types ceramic after their finishing 2) compare three techniques using kits. Methods: Seventy-two specimens were obtained from two 3Y-TZP zirconia. After sintering, a layer glass-based fluorapatite veneering was applied over 24 one cera...

Digitalization has become part and parcel of contemporary prosthodontics with the probability of most of the procedures being based on the digital techniques in the near future. This digital revolution started in the latter half of the 20th century by converting analog objects/signals into digital bits and bytes. Recent developments in all-ceramic materials and systems of computer-aided designi...

BACKGROUND/AIM Fracture toughness determines functional crown strenght and prevents damages on ceramics during mastication. There is a lack of relevant literature data about fracture toughness of crowns made by feather-edge preparation. Mechanical testing of ceramic samples is supposed to show if feather-edge tooth preparation is a successful method for making ceramic crowns without any risk of...