Effect of cementation protocols on the fracture load of bilayer ceramic crowns manufactured by the Rapid Layer Technology.

To evaluate the fracture load of bilayer ceramic crowns manufactured by Rapid Layer Technology (RLT) after different cementation protocols of the veneering ceramic to the zirconia infrastructures. Sixty epoxy resin preparations simulating a molar tooth were obtained and 60 zirconia infrastructures and feldspathic crowns were manufactured by RLT and divided into 6 groups according to the cementation protocol at the interface to veneering ceramic (n=10): Ctr- control: conventional resin cement; Al- Al2O3 sandblasting 50µm + conventional resin cement; Al/MDP- Al2O3 sandblasting (50µm) + resin cement with MDP; Sil- silicatization 30µm + conventional resin cement; Gl/HF- glaze + hydrofluoridric acid (5%,60s) + silane + conventional resin cement; Gl- glazing as bonding agent. The feldspathic ceramic internal surface was etched with fluoridric acid (5%) + silane followed by cementation according to respective protocols.

Clinical performance of monolithic polymer-infiltrated ceramic and lithium disilicate posterior crowns: A controlled, randomized, and double-blind clinical trial.

Statement Of Problem: The success rate of monolithic polymer-infiltrated ceramic posterior crowns after 1 year is unclear.

Purpose: The purpose of this controlled, randomized, and double-blind clinical trial was to evaluate the performance of posterior complete crowns in polymer-infiltrated and lithium disilicate ceramics and to assess the impact of oral rehabilitation on esthetic satisfaction, quality of life, and periodontal health.

Material And Methods: A total of 33 crowns were provided in 18 participants allocated to 2 groups: Control (Lithium disilicate-IPS e.

Flexural strength, surface roughness, micro-CT analysis, and microbiological adhesion of a 3D-printed temporary crown material.

Objective: To evaluate the thermocycling effect of 3D-printed resins on flexural strength, surface roughness, microbiological adhesion, and porosity.

Materials And Methods: 150 bars (8 × 2 × 2 mm) and 100 blocks (8 × 8 × 2 mm) were made and divided into 5 groups, according to two factors: "material" (AR: acrylic resin, CR: composite resin, BIS: bis-acryl resin, CAD: CAD/CAM resin, and PRINT: 3D-printed resin) and "aging" (non-aged and aged - TC). Half of them were subjected to thermocycling (10,000 cycles).

Biaxial flexure strength and physicochemical characterization of a CAD/CAM lithium disilicate ceramic: effect of etching time, silane, and adhesive applications.

Objective: To evaluate the effect of different acid etching time and bonding agent (silane and/or adhesive system) on biaxial flexural strength and physico-chemical properties of a lithium disilicate ceramic.

Material And Methods: One hundred twenty ceramic discs were made and divided into 8 groups (n = 15) according to factors "etching time" (20 and 120 s) with hydrofluoric acid (HF) and "bonding agent" (C, no bonding agent; S, silane, A, adhesive; and SA, silane + adhesive). After surface treatment, a resin cement layer was applied to the surface and all specimens were subjected to biaxial flexural strength (BFS) test with treated surfaces loaded in tension (1 mm/min).

Fatigue strength of 5Y-FSZ: glazing and polishing effects.

Objective: The aim of this study was to evaluate the effect of four different finishing procedures on the fatigue strength of a fully stabilized zirconia (5Y-FSZ) material.

Materials And Methods: Disc-shaped specimens of a 5Y-FSZ (Katana UTML, Kuraray Noritake) were made (ISO 6872-2015), grinded with 600- and 1200-grit silicon carbide paper, sintered as recommended, and randomly assigned into four groups according to the finishing technique: C (control, as-sintered), P (polished with polishing rubbers), G (glaze application - powder/liquid technique), and PG (polished with polishing rubbers + glaze application - powder/liquid). Then fatigue strength (staircase method), X-ray diffraction (XRD), and scanning electron microscopy (SEM) analyses were performed.

Effect of finishing/polishing techniques and aging on topography, C. albicans adherence, and flexural strength of ultra-translucent zirconia: an in situ study.

Objective: To investigate the influence of different finishing/polishing techniques and in situ aging on the flexural strength (σ), surface roughness, and Candida albicans adherence of 5 mol% yttria-stabilized zirconia (ultratranslucent zirconia).

Materials And Methods: A total of 120 zirconia bars (Prettau Anterior, Zirkonzahn) with dimensions of 8 × 2 × 0.5 mm were divided into 8 groups (n = 15) according to two factors: "in situ aging" (non-aged and aged (A)) and "finishing/polishing" (control (C), diamond rubber polishing (R), coarse grit diamond bur abrasion (B), and coarse grit diamond bur abrasion + diamond rubber polishing (BR)).

Effects of ionizing radiation on surface properties of current restorative dental materials.

To investigate the impact of radiotherapy on surface properties of restorative dental materials. A conventional resin composite-CRC (Aura Enamel), a bulk-fill resin composite-BFRC (Aura Bulk-fill), a conventional glass ionomer cement-CGIC (Riva self cure), and a resin-modified glass ionomer cement-RMGIC (Riva light cure) were tested. Forty disc-shaped samples from each material (8 mm diameter × 2 mm thickness) (n = 10) were produced according to manufacturer directions and then stored in water distilled for 24 h.

Cleaning and Surface Treatment Protocols for Repair of Aged Y-TZP with Composite Resin.

The purpose of this study was to evaluate the cleaning and surface treatment techniques in the repair of aged and contaminated yttrium oxide-stabilized tetragonal polycrystalline zirconia (Y-TZP). From a total of 80 specimens of Y-TZP, 60 were subjected to aging simulation in a buccal environment with degradation in an autoclave for 24 hours (127°C/1.5 bar) and contaminated with Streptococcus mutans.

Effect of Consecutive Firings on the Optical and Mechanical Properties of Silicate and Lithium Disilicate Based Glass-Ceramics.

Purpose: To evaluate the effect of multiple firings on the optical and mechanical properties of two dental CAD/CAM glass-ceramics.

Materials And Methods: A total of 45 specimens of each lithium disilicate-LD (IPS E.max CAD, Ivoclar Vivadent) and zirconia lithium silicate-ZLS (Vita Suprinity, Vita Zahnfabrik) material were prepared in a disk shape.

Effect of finishing/polishing techniques and low temperature degradation on the surface topography, phase transformation and flexural strength of ultra-translucent ZrO ceramic.

Objective: To investigate the effect of different surface finishing and polishing regimes and low temperature degradation on flexural strength, phase transformation and surface topography of ultra-translucent ZrO ceramic.

Methods: 300 (n=15/group) of conventional zirconia (Z: Ice Zirkon Transluzent) and ultra-translucent zirconia (UT: Prettau Anterior) bar-specimens were made and divided according to the "Finishing/Polishing" - (C - Control, B - diamond rubber polishers, P - adjusting with burs, PB - adjusting with burs+diamond polishers, PG - adjusting with burs+glaze), "Low temperature Degradation (LTD)" (with or without a treatment at 127°C, 1.7bar/24h).

Effect of different repair methods on the bond strength of resin composite to CAD/CAM materials and microorganisms adhesion: An in situ study.

Objective: To evaluate the influence of different repair protocols andin situ aging on colony forming units (CFU) and shear bond strength (SBS) between CAD/CAM materials and resin composite.

Methodology: 150 blocks (6 × 5 × 2.5 mm) were made out of each restorative material (CAD/CAM resin composite -RC), polymer-infiltrated ceramic - PIC and glass ceramic (VS), totaling 450 blocks.

Can low-fusing glass application affect the marginal misfit and bond strength of Y-TZP crowns?

To evaluate the effect of different surface treatments on the marginal misfit and retentive strength between Y-TZP crowns and an epoxy resin. Forty (40) epoxy resin (G10) abutments (height: 5mm, conicity: 60, finish line: large chamfer) with equal dimensions were milled and included in polyurethane to simulate the periodontal ligament. Next, 40 Y-TZP crowns (thickness: 1mm) were milled (Cerec in Lab) and randomly divided into four groups (n=10) according to the surface treatment: GS(glaze spray), GP(glaze powder/liquid), P(zirconia primer) and RS(tribochemical silica coating).

Mechanical Behavior of Different Micro Conical Abutments in Fixed Prosthesis.

Purpose: To evaluate the biomechanical behavior between two different micro conical abutments: two-piece and one-piece abutments.

Materials And Methods: Four groups were divided according to the prosthetic connection (internal or external hexagon) and abutment type. The vertical misfit between the abutment and implant was evaluated under stereomicroscope.

Carbon film coating of abutment surfaces: effect on the abutment screw removal torque.

Purpose: To evaluate the effect of diamond-like carbon (DLC) coating of prefabricated implant abutment on screw removal torque (RT) before and after mechanical cycling (MC).

Materials And Methods: Fifty-four abutments for external-hex implants were divided among 6 groups (n = 9): S, straight abutment (control); SC, straight coated abutment; SCy, straight abutment and MC; SCCy, straight coated abutment and MC; ACy, angled abutment and MC; and ACCy, angled coated abutment and MC. The abutments were attached to the implants by a titanium screw.

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.

Shear bond strength of orthodontic brackets bonded using halogen light and light-emitting diode at different debond times.

The aim of this in vitro study was to compare the photoactivation effects of QTH (Quartz-Tungsten-Halogen) and LED (Light-Emitting Diode) on the SBS (Shear Bond Strength) of orthodontic brackets at different debond times. Seventy-two bovine lower incisors were randomly divided into two groups according to the photoactivation system used (QTH or LED). The enamel surfaces were conditioned with Transbond self-etching primer, and APC (Adhesive Pre-Coated) brackets were used in all specimens.