Purpose: To determine the curing potential and color stability of resin-based luting materials for aesthetic restorations.
Material And Methods: Four resin-based luting agents were tested: traditional dual-activated resin cement (RelyX ARC, ARC), amine-free dual-activated resin cement (RelyX Ultimate, ULT), light-activated resin cement (RelyX Veneer, VEN), and pre-heated restorative resin composite (Filtek Supreme, PHC). Degree of C=C conversion was determined by infrared spectroscopy (n=3) with direct light exposure or with interposition of 1.
Objective: To determine if material's translucency influences the cure efficiency and color stability of resin-based composites (RBCs).
Methods: Four commercially-available RBCs indicated for aesthetic restorations were selected in different translucent/opaque shades: IPS Empress Direct (IED) A3 Dentin, A3 Enamel, Trans 20, and Trans 30; Filtek Z350 XT (FZX) A3D, A3B, A3E, and CT; Estelite ∑ Quick (EQ) OA3, A3, and CE; and Opallis (OP) DA3, EA3, and T-Neutral. Color was obtained in the L'C'h' system at three distinct periods: 24h after photoactivation (baseline), after 30d of water storage (WS), and after 30d of coffee storage (CS).
Objective: To determine the color stability (CS) and hardness' decrease (HD) of two commercial resin-based composites (RBCs), after in situ staining conditions (SC).
Methods: Six disc-shaped specimens (6 × 2 mm) of two RBCs-Filtek Z350 XT (FZX) and IPS Empress Direct (IED)-were randomly distributed into palatal devices. Eight volunteers (aged 20-30 years) participated in this study.
The aim of this study was to determine the influence of photoinitiator systems on physical-chemical properties of flowable composites. Conventional (CFC), composed by bisphenol-glycidyl dimethacrylate (BisGMA)+triethyleneglycol dimethacrylate (TEGDMA), and self-adhesive (SAFC), composed by BisGMA+TEDGMA+bis{2-(methacryloyloxy) ethyl} phosphate (2MP), flowable composites were developed. Five photoinitiator systems were tested: camphorquinone (CQ), ethyl-4-dimethylaminobenzoate (EDMAB), diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), phenylbis (2,4,6-trimethylbenzoyl)phosphine oxide (BAPO), CQ+EDMAB+TPO and CQ+EDMAB+BAPO.
View Article and Find Full Text PDFObjective: To determine the optical and surface properties of model resin-based composites made with distinct nanoparticle sizes but equalized surface area, among them, before and after ageing.
Methods: Model resin-based composites based on BisGMA/TEGDMA (50:50mol%) were loaded with three different fumed silica filler content (7nm/examethyldisilazane, 12nm/octylsilane, and 16nm/dimethylchlorosilane), but with equivalent surface area (BET method). The optical and surface properties of the disk-shaped specimens were measured in 24h after photoactivation (baseline) and repeated after water storage (90days at 37°C), and after abrasion (20,000 cycles of brushing).
Objective: This study aims to determine the influence of photoinitiators' combinations on the hardness, depth of cure, and color of model resin composites.
Materials And Methods: The composites were formulated by a mixture of BisGMA and triethyleneglycol dimethacrylate (60:40 mol), with barium-aluminum-silicate glass and silicon dioxide particles as inorganic fillers (60 wt%). Three photoinitiator types were tested: camphorquinone/amine (CQ), monoacylphosphine oxide (TPO), and bysacylphosphine oxide (BAPO).
Objectives: This study evaluated the effect of brushing orthodontic clear ligatures with a whitening dentifrice containing a blue pigment (Close Up White Now, Unilever, London, UK) on their color stability, when exposed to a staining agent.
Materials And Methods: Ligatures from 3M Unitek (Monrovia, CA, USA) and Morelli (Sorocaba, SP, Brazil) were tested. Baseline color measurements were performed and nonstained groups (control) were stored in distilled water whereas test groups were exposed for 1 hour daily to red wine.
Objective: To establish the relationship between photoinitiator system and nanofiller size on the optical properties and cure efficiency of model composites.
Methods: Model composites based on BisGMA/TEGDMA (60:40mol%) were loaded with 40wt% of 7nm or 16nm-sized filler particles. One of the following photoinitiator systems was added: camphorquinone (CQ) associated with an amine (EDMAB), monoacylphosphine oxide (TPO), or bysacylphosphine oxide (BAPO).
Objectives: To investigate the influence of nanoscale inorganic content over optical and surface properties of model composites before and after ageing.
Methods: Three model composites were formulated with silica fillers in nanoscale of 7 nm (G1), 12 nm (G2) and 16 nm (G3), at 45.5% by weight in a matrix of BisGMA/TEGDMA 1:1.