Effect of Surface-Etching Treatment, Glaze, and the Antagonist on Roughness of a Hybrid Ceramic after Two-Body Wear.

Stains and glaze are effective procedures for achieving an aesthetic smoothness on indirect restorations. Thus, the effect of surface-etching treatments previous to the stain layer and the glaze application on the occlusal and antagonist wear of a hybrid ceramic were evaluated against different antagonists. Disc-shaped samples were prepared from polymer-infiltrated ceramic network (PICN) blocks.

Interfacial Fracture Energy Between New Translucent Zirconias and a Resin Cement.

Purpose: To determine the interfacial fracture energy (IFE) and stress distribution of Brazil-nut-shaped specimens made of translucent zirconia and resin cement.

Materials And Methods: Three types of translucent zirconia were used: 3Y-TZP (high, Vita YZ HT), 4Y-TZP (super, Vita YZ ST), and 5Y-TZP (extra, Vita YZ XT). The adhesive surfaces were air abraded and 10-MDP-based resin cement was used.

CAD-FEA modeling and fracture resistance of bilayer zirconia crowns manufactured by the rapid layer technology.

In the RLT (Rapid Layer Technology), veneering ceramic and framework are fabricated by computer-aided design/computer-aided manufacturing (CAD/CAM) and then cemented to obtain the restoration. This study aimed to evaluate the effect of the thickness of veneering ceramic manufactured by the RLT technique on the fracture resistance (FR) of bilayer crowns with zirconia frameworks. Twenty zirconia frameworks and twenty feldspathic posterior crowns with two different veneering ceramic occlusal thicknesses (1mm=TF1; 2mm=TF2) were manufactured using CAD/CAM system.

Effect of surface treatment and glaze application on shade characterized resin-modified ceramic after toothbrushing.

Statement Of Problem: The extrinsic characterization with pigments and glaze application on the surface of ceramic restorations promotes individualization and esthetics. However, whether this characterization is resistant to toothbrushing abrasive wear is unclear.

Purpose: The purpose of this in vitro study was to investigate the abrasive wear resistance of characterized and glazed resin-modified ceramic with different surface treatments before characterization.

Novel speed sintered zirconia by microwave technology.

Objective: Continuous efforts have been made to hasten the zirconia densification process without compromising properties. This study evaluated the long-term structural durability of microwave speed-sintered zirconia (MWZ) relative to a conventionally sintered zirconia (CZ).

Methods: As-machined dental 3Y-TZP discs (Ø12 × 1.

Long-term fracture load of all-ceramic crowns: Effects of veneering ceramic thickness, application techniques, and cooling protocol.

Background: To evaluate, , the effects of the cooling protocol, application technique, and veneering ceramic thickness on the fracture resistance of ceramic crowns with Y-TZP frameworks.

Material And Methods: 80 frameworks were made from zirconia by the CAD/CAM technique and divided into 8 groups (n = 10) according to the factors: "application technique" (stratified-L and pressed -P), "thickness" (1 mm and 2 mm), and "cooling protocol" (slow-S and fast-F) of the feldspathic veneering ceramic. After, all crowns were cemented over G10 preparations with resin cement (Panavia F, Kuraray), mechanically cycled (2x106 cycles, 200 N, 3Hz), and subjected to the axial compression resistance test (0.

Minimal tooth preparation for posterior monolithic ceramic crowns: Effect on the mechanical behavior, reliability and translucency.

Objective: Despite the increased use of monolithic crowns, their performance has yet to be determined when the minimal tooth preparation (MTP) principle is considered. The goal of this study was to evaluate the effect of MTP on the mechanical behavior, reliability and translucency of posterior monolithic ceramic crowns.

Methods: Dentin analogues were machined using two preparation designs (0.

Survival probability of zirconia-reinforced lithium silicate ceramic: Effect of surface condition and fatigue test load profile.

Objectives: The present investigation evaluated the step stress accelerated test (SSALT) load profiles on the survival probability of a glass ceramic under two surface conditions (polished or roughened).

Methods: Suprinity-ZLS blocks (Vita Zhanfabrik) were shaped into cylinders, cut in a sawing machine, and crystalized according to the manufacturer's instructions. 60 discs were obtained (Ø=12mm, thickness=1.

A Powdering Technique for Veneering Zirconia and Its Effect on the Flexural Strength of Ceramic Bilayers.

The aim of this study was to assess the powdering technique and its effects on the flexural strength of bilayered zirconia. Bars made of zirconia partially stabilized by yttrium (Y-TZP) received porcelain by the following techniques (n = 10 per group): (1) L: VM9 application; (2) P: powdering technique + VM9 application; (3) C: Y-TZP coloring before sintering + Y-TZP sintering + VM9 application; or (4) CP: Y-TZP coloring before sintering + Y-TZP sintering + powdering technique + VM9 application. The powdering technique consisted of the application of VM9 margin powder followed by sintering.

Microstructural analysis and reliability of monolithic zirconia after simulated adjustment protocols.

Objective: To investigate the microstructural properties and reliability of zirconia partially stabilized by yttrium oxide (Y-TZP) for use in monolithic form (Vita YZ HT, Vita Zahnfabrik, Germany) after different clinical adjustment protocols simulation. One-hundred and sixty two Y-TZP discs of high translucency were divided into 6 groups (n=27), according to simulated adjustments: S-Y-TZP as sintered; G-glazed Y-TZP; DbG-Y-TZP with diamond bur adjustment simulation followed by glaze application; GDb-glazed Y-TZP adjusted with diamond bur; DbDrG-Y-TZP with adjustment simulation with diamond bur and polishing kit (diamond rubber), followed by glaze; GDbDr-glazed Y-TZP with adjustment simulation with diamond bur followed by polishing kit.

Methods: After monotonic testing under biaxial flexure (n=3), remaining specimens were distributed into 3:2:3 ratio and tested under step-stress accelerated life testing.

Fracture of Zirconia Abutment with Metallic Insertion on Anterior Single Titanium Implant with Internal Hexagon: Retrieval Analysis of a Failure.

This case report presents a retrieval analysis of a screw-retained one-piece restoration with the veneering ceramic fired directly onto the zirconia abutment that fractured during insertion. A patient who experienced root fracture of a maxillary left central incisor received a titanium implant on the same day as extraction. After delayed implant loading, a two-piece zirconia abutment with metallic insertion was customized.

Bonding of the Polymer Polyetheretherketone (PEEK) to Human Dentin: Effect of Surface Treatments.

Polyetheretherketone (PEEK) is a material suitable for frameworks of fixed dental prostheses. The effect of different surface treatments on the bond strength of PEEK bonded to human dentin was evaluated. One hundred PEEK cylinders (3 mm×3 mm) were divided into five groups according to surface treatment: silica coating, sandblasting with 45 μm Al2O3 particles, etching with 98% sulfuric acid for 5, 30 and for 60 s.

Influence of insertion techniques for resin cement and mechanical cycling on the bond strength between fiber posts and root dentin.

Purpose: To evaluate the effect of the insertion technique for resin cement and mechanical cycling on the bond strength between fiber posts and root dentin.

Materials And Methods: Sixty-four single-rooted bovine teeth were endodontically prepared to receive glass-fiber posts. The insertion of cement into the root canal was performed using one of the following techniques: POS, insertion with the post; LEN, the use of a lentulo-type drill; EXP, insertion with a straight-tip explorer; or CEN, the use of a Centrix syringe.

Tooth discoloration induced by endodontic phenothiazine dyes in photodynamic therapy.

Objective: This study sought to assess if discoloration of tooth structures occurs after photodynamic therapy (PDT) and to determine the efficacy of a protocol to remove the photosensitizers.

Background Data: PDT has been used in root canal treatment to enhance cleaning and disinfection of the root canal system. PDT uses a low power laser in association with a dye as a photosensitizer.

Finite element analysis of the influence of geometry and design of zirconia crowns on stress distribution.

Purpose: To evaluate the influence of the geometry and design of prosthetic crown preparations on stress distribution in compression tests, using finite element analysis (FEA).

Materials And Methods: Six combinations of 3D drawings of all-ceramic crowns (yttria-stabilized zirconia framework and porcelain veneer) were evaluated: F, flat preparation and simplified crown; FC, flat preparation and crown with contact point; FCM, flat preparation and modified crown; A, anatomical preparation and simplified anatomical crown framework; AC, anatomical preparation and crown with contact point; and ACM, anatomical preparation and modified crown. Bonded contact types at all interfaces with the mesh were assigned, and the material properties used were according to the literature.

Removable partial dentures: use of rapid prototyping.

The CAD/CAM technology associated with rapid prototyping (RP) is already widely used in the fabrication of all-ceramic fixed prostheses and in the biomedical area; however, the use of this technology for the manufacture of metal frames for removable dentures is new. This work reports the results of a literature review conducted on the use of CAD/CAM and RP in the manufacture of removable partial dentures.

Effect of the layering technique on bond strength and cohesive resistance of a porcelain-zirconia system.

Purpose: To evaluate the influence of the number of porcelain layers on its cohesive strength and on bonding to zirconia.

Materials And Methods: Y-TZP blocks were cut into 1 cm3 specimens (n = 30). The feldspathic porcelain (V9) was applied to the zirconia in different numbers of layers up to 1 cm total thickness (n = 10): ZP1 - one layer; ZP2 - two layers; ZP3 - three layers.

Surface agents' influence on the flexural strength of bilaminated ceramics.

The objective of this study was to evaluate the influence of different surface agents on the flexural strength of a ceramic system. Eighty bar-shaped specimens of zirconia were divided into four groups according to the agent to be used: group Control--to be cleaned with alcohol; group VM9--application of a fluid layer of porcelain; group Effect Bonder--application of a bonding agent; and group Coloring Liquid--application of coloring liquid. All specimens received the porcelain application by the layering technique and were then subjected to thermocycling.

Stress distribution around osseointegrated implants with different internal-cone connections: photoelastic and finite element analysis.

The goal of this study was to evaluate the distribution of stresses generated around implants with different internal-cone abutments by photoelastic (PA) and finite element analysis (FEA). For FEA, implant and abutments with different internal-cone connections (H- hexagonal and S- solid) were scanned, 3D meshes were modeled and objects were loaded with computer software. Trabecular and cortical bones and photoelastic resin blocks were simulated.

Morphology and bacterial colonisation of tooth/ceramic restoration interface after different cement excess removal techniques.

Objectives: To evaluate the influence of different protocols for resin cement removal during cementation on biofilm formation.

Methods: Twenty-eight ceramic blocks, which were injected under pressure, were placed over enamel blocks obtained from freshly extracted bovine incisors. The ceramic blocks were cemented to the enamel blocks using a dual-cured resin cement and the excess resin was removed according to the experimental group: TS: Teflon spatula; BR: brush; BR+: brush and polishing; SB+: scalpel blade and polishing.