Changes in Optical Characteristics and Surface Topography of CAD/CAM Materials after Bleaching Applications: An AFM Evaluation
Cengiz Yanardag, Esra
Purpose: To evaluate the effect of in-office and at-home bleaching agents on color changes (ΔE00 ), translucency (TP00 ), whiteness (WID ), surface roughness (Ra ), and surface topography (Rsk and Rku ) of a resin nano-ceramic and a polymer-infiltrated ceramic network CAD/CAM material. Materials and methods: Sixty specimens (6 mm × 7 mm × 1.3 mm) were prepared from Lava Ultimate (LU) and Vita Enamic (VE). The specimens were divided into 6 groups according to the bleaching agents applied (n = 10/group): control, Perfect Bleach Office + (PBO), Opalescence Boost (OB), Perfect Bleach (PB) with 10% and 16% carbamide peroxide and Whiteness Perfect (WP). ΔE00 values were calculated before and after bleaching procedures with a spectrophotometer using the CIEDE2000 formula. ΔTP00 and ΔWID values w...
Derin dentin çürüklerinin tedavisinde alternatif yeni yöntemler
Cengiz Yanardag, Esra
Günümüzde modern diş hekimliği kapsamında, diş dokularının maksimum oranda korunması ve fonksiyon görmesi için minimal invaziv yöntemler uygulanmaktadır. G.V. Black tarafından tanımlanmış olan geleneksel görüşe bağlı kalınarak uygulanan derin dentin çürüğü tedavilerinde tüm çürük dokunun uzaklaştırılması, pulpanın perforasyonuna dolayısıyla endodontik girişimlere ve bazı durumlarda çekime neden olabilmektedir. Dişin ağızda kalma süresi, fonksiyonu ve prognozu açısından önemli bir etken olan pulpanın vitalitesinin daha uzun süre korunabilmesi amacıyla adeziv sistemler ve restoratif materyallerdeki yeni gelişmelerle günümüzde pek çok yeni tedavi yaklaşımı ve materyal geliştirilmiştir. Bu derlemede derin dentin çürüğü varlığında çürüğün uzaklaştırılmasındaki selektif yaklaşımlar, k...
Micro-shear bond strength of resin cements to Er, Cr: YSGG laser and/or acid etched enamel
Cengiz Yanardag, Esra
The purpose of this study was to evaluate the effect of Er,Cr:YSGG laser irradiation and/ or acid etching on the micro-shear bond strength (µSBS) of two different dual-cured resin cements to human enamel. 24 intact, extracted molars were sectioned longitudinally and randomly divided into three subgroups according to three surface pretreatment methods: (1) Er,Cr:YSGG laser (Waterlase MD, Biolase) irradiation was used with a power setting of 2 W (55% water and 65% air), and a repetition rate of 20 Hz for 10s; (2) 37% phosphoric acid application for 20s; (3) Re-etching with phosphoric acid for 20s after the Er,Cr:YSGG laser irradiation as in group1. 12 enamel discs for each of the resin cements (Panavia F2.0 and Variolink N) were prepared and three cylinders of resin cements were bon...
The Effect of Surface Treatments on the Mechanical and Optical Behaviors of CAD/CAM Restorative Materials
Cengiz Yanardag, Esra
Purpose: To evaluate the effect of different surface treatments on mechanical and optical properties of lithium disilicate ceramic (IPS e.max CAD), 2 resin nanoceramics (Lava Ultimate, GC Cerasmart), and polymer-infiltrated ceramic network material (Vita Enamic). Materials and methods: CAD/CAM blocks were sectioned into 4 × 1 × 14 mm3 bars for three-point bending test and 1 × 8 × 8 mm3 square specimens were obtained for color and translucency measurements. Bar-shaped and square specimens were divided into five groups according to the surface treatment method as: control (no treatment), hydrofluoric acid etching, airborne-particle abrasion, 2 W and 3 W Er,Cr:YSGG laser irradiation (n = 10). Three-point bending test was carried out on a universal test machine with a 1 mm/min crosshead spe...
Effect of 2 Bleaching Agents with a Content of High Concentrated Hydrogen Peroxide on Stained 2 CAD/CAM Blocks and a Nanohybrid Composite Resin: An AFM Evaluation
Cengiz Yanardag, Esra
The aim of this study was to evaluate color stability of 3 restorative materials, discoloration ability of different solutions, efficacy of 2 office bleaching agents, and surface roughness and topography. Sixty specimens for Clearfil Majesty Esthetic (CME), Lava Ultimate (LU), and Vita Enamic (VE) were prepared. They were immersed into 3 staining solutions for 2 weeks and then they were bleached. According to the measured L⁎, a⁎, and b⁎ parameters described by CIELAB system, color changes (ΔE00), translucency parameters (TP), whiteness index values (W⁎), and changes in closeness to pure white (ΔW⁎) were calculated. Then 3 specimens from each group were scanned with an atomic force microscope for surface analysis. After staining, CME groups and control groups of LU and VE showed clinically ...
The effect of hydrogen peroxide and subsequent resveratrol application to CAD-CAM blocks on the cell viability of fibroblasts
Cengiz Yanardag, Esra
The aim is to assess viability of fibroblasts exposed to 2 CAD-CAM blocks and a nanohybrid resin after application of hydrogen peroxide (HP) and resveratrol with 2 extraction media at 24 h, 48 h, and 72 h. Eighteen specimens were obtained from Lava Ultimate (LU), Vita Enamic (VE), and Grandio (GR). Specimens of each material were divided into 3 groups (material only, bleached, resveratrol applied) for 2 extraction media as artificial saliva (AS) and phosphate buffer saline (PBS) (n = 3). For bleached group, 40% HP was applied to specimens for 20 min twice. For resveratrol group, 0.5 µM resveratrol was applied after bleaching for 10 min. Mouse fibroblast cells were exposed to extracts of each group. The viability of cells was determined with MTT assay at 24 h, 48 h, and 72 h. Cell viability...
The effect of resveratrol application on the micro-shear bond strength of adhesive to bleached enamel
Cengiz Yanardag, Esra
The aim is to investigate the effect of resveratrol on micro-shear bond strength (µSBS) of adhesive to enamel after 40% hydrogen peroxide application. For µSBS test, 50 teeth were obtained, 2/3 of crowns were embedded into acrylic resin. After application of hydrogen peroxide twice, teeth were randomly allocated to control group and 9 groups (n = 15) according to concentrations (0.5, 1, 2 µM) and application periods (10, 30, 60 min) of resveratrol. Following, composite resin was placed onto enamel surfaces using 3 tygon tubes for each tooth. µSBS test was performed and failure modes were displayed. To analyze µSBS values, Kruskal Wallis and Mann-Whitney U tests were performed. µSBS values of 1 µM resveratrol for 10 min applied group were statistically higher than control group (p < 0.05). ...
Color difference of composite resins after cementation with different shades of resin luting cement
Cengiz Yanardag, Esra
The purpose of this study was to evaluate the color difference of nanohybrid and ormocer-based composite resins with different thicknesses when 4 different shades of resin luting cement were used. 56 disc specimens of each composite resin (Aelite aesthetic enamel, Ceram-X mono) with 0.5 and 1 mm thicknesses were fabricated. Baseline color measurements were performed using a clinical spectrophotometer. The specimens of each thicknesses of each resin were randomly divided into 4 groups according to the shades of resin luting cement (white/A1, yellow/universal/A3, transparent and white opaque) (n = 7). Mixed resin cement was applied onto the resin specimens using a Teflon mold in 0.1 mm thickness. Color measurements of cemented composite resin specimens were repeated and color difference (∆E)...
Effects of Staining Beverages and Office Bleaching Agents on the Optical Characteristics and Surface Topography of Maxillary Incisor Teeth
Cengiz Yanardag, Esra
BACKGROUND/AIMS: The aim of this study was to evaluate the staining abilities of different beverages, the efficacy of two office bleaching agents and the effect of bleaching on the surface topography of maxillary incisors. MATERIALS AND METHODS: Sixty crowns of maxillary incisors were obtained and immersed in distilled water for 24 hours. After baseline color measurements were made, the specimens were divided into three groups according to three immersion solutions [Turkish coffee (TC), red wine (RW), and distilled water (DW)]. At the end of the staining period, color measurements were repeated and then the specimens of each group were divided into two subgroups and Perfect Bleach Office+ (PBO+) or Opalescence Boost (OB) were applied. After bleaching, the color measurements were recorde...