The present study aimed to evaluate the influence of titanium surface nanotopography on the initial bacterial adhesion process by in vivo and in vitro study models. Titanium disks were produced and characterized according to their surface topography: machined (Ti-M), microtopography (Ti-Micro), and nanotopography (Ti-Nano). For the in vivo study, 18 subjects wore oral acrylic splints containing 2 disks from each group for 24 h (n = 36).
View Article and Find Full Text PDFObjective: to investigate the effect of different concentrations of chitosan added to experimental resins containing either BAPO or camphorquinone (CQ) as photoinitiators, regarding degree of conversion (DC), flexural strength (FS), flexural elastic modulus (E), Knoop microhardness (KHN), cytotoxicity, genotoxicity and antimicrobial activity.
Methods: Experimental resins with polymeric matrix of BisGMA and TEGDMA was added either 0.5 wt% BAPO or 0.
Background: Nanoparticles (NPs) have gained significant attention in various fields due to their unique properties and potential applications. Polymethyl methacrylate (PMMA) is an acrylic resin widely used in dentistry and medicine. However, the effect of different types of NP fillers on the physical properties of PMMA-based resins has not been thoroughly explored in the literature.
View Article and Find Full Text PDFStatement Of Problem: Digital technologies have brought different workflows to prosthetic rehabilitations, but analyses of the available processes and their influence on the marginal fit of complete crowns are lacking.
Purpose: The purpose of this in vitro study was to evaluate the marginal discrepancy of lithium disilicate complete crowns made with different workflows.
Material And Methods: Fifty lithium disilicate crowns were made with 5 different workflows (n=10): G1-Analog (control): conventional flow/pressed crown; G2-Hybrid: hybrid flow/milled crown; G3-Hybrid: hybrid flow/pressed crown; G4-Hybrid: hybrid flow/printed wax pattern/pressed crown; G5-Digital: digital flow/milled crown.
Thisstudy aimed to evaluate the effect of the electric current direction application on the resin composite-dentin bond strength using three adhesive systems. Human molar teeth were distributed according to the adhesive system (two-step self-etch - Clearfil SE Bond, Kuraray [CSE]; one-step self-etch - Single Bond Universal, 3M ESPE [SBU]; and two-step etch-and-rinse - Adper Single Bond 2, 3M ESPE [SB2]), electric current direction (without electric current - control, direct and reverse electric currents - 35µA), and storage time (24h - immediate and 6 months). Resin composite blocks (Filtek Z350XT, 3M ESPE) were bonded to dentin.
View Article and Find Full Text PDFThis study evaluated stresses generated at maxillary central incisor (21) root restored with lithium disilicate crown (LDC), and glass fiber (GFP) or polyetheretherketone (PEEK) post. 3D models created by computed tomographic image (i-CAT Cone Beam 3D Dental Imaging System) reproduced maxillary central incisor. Each model had prosthetic LDCs (2.
View Article and Find Full Text PDFBackground: The treatment of dentin before the use of self-adhesive cements is still a crucial point to achieve the best bond strength values. The objective of this study was to evaluate the bond strength between dentin and composite resin using different adhesion strategies with self-adhesive resin cement.
Material And Methods: Forty healthy third human molars were randomly divided into 4 groups (n = 10): CA (control); application of self-adhesive cement (Rely X U200, 3M ESPE), AD + CA: only application of conventional adhesive (Adper Single Bond 2, 3M ESPE) + self-adhesive cement, AC + AD + CA; conditioning with 37% phosphoric acid for 15 seconds + application of conventional adhesive + self-adhesive cement and AC + CA; conditioning with 37% phosphoric acid for 15s + self-adhesive cement.
Objectives: The aim of this study was to evaluate using finite element analysis (FEA), the stress distribution in prostheses (lithium disilicate crowns) on monotype zirconia implants with and without cantilever in the anterior region of the maxilla.
Materials And Methods: From a virtual reconstruction of bone model of the toothed maxilla from a computed tomography, three models (groups) were created: Zr (11-21)-implants placed in the area of 11 and 21 with cantilever; Zr (12-22)-implants placed in the area of 12 and 22 without cantilever; and Zr (11-22)-implants intercalated placed in the area of 11 and 22. In all models, monotype zirconia implant (4.
Objective: This study aimed to evaluate the bond strength between lithium disilicate ceramic and resinous cement when silane (Prosil, FGM) was applied in different amounts of layers under heating or not.
Materials And Methods: Sixty IPS E-max CAD ceramic (Ivoclar) was used. They were conditioned with 10% hydrofluoric acid for 20 seconds.
Objectives: The aim of this study was to evaluate the Knoop hardness (KH), cross-link density (CLD), water sorption (WS), water solubility (WSB), and volumetric shrinkage (VS) of experimental resins blends containing a monomethacrylate with low-polymerization shrinkage.
Materials And Methods: A blend of bisphenol glycidyl methacrylate (BisGMA) as base monomer was formulated with (Bis-GMA)/triethyleneglycol dimethacrylate (TEGDMA), Bis-GMA/isobornyl methacrylate (IBOMA), or Bis-GMA/TEGDMA/IBOMA in different concentrations (40, 50, or 60 wt%). The camphorquinone (CQ)/2-(dimethylamino) ethyl methacrylate (DMAEMA) was used as the photoinitiator system.
Background: Different materials have been incorporated into the polymethylmethacrylate matrix to improve its performance. The aim of this study was to evaluate the degree of conversion (DC), the flexural strength (FS), the elasticity modulus (EM), and the effect of exposure to food-simulating liquids prior to brushing simulation on the gloss loss (GL) of experimental acrylic resins modified by nanoparticles.
Material And Methods: Three different types of nanoparticles; silicon oxide (SiO2), cerium oxide (CeO2) and titanium oxide (TiO2) were added to a poly (methylmethacrylate) matrix, in proportions of 0.
Statement Of Problem: Short and extra-short implants with Morse taper connections were developed to avoid grafting procedures. How the stresses around these implants differ with abutments of different angulations is unclear.
Purpose: The purpose of this finite element study was to analyze the stress distribution in different structures (abutment, implant, and bone) of an extra-short implant with a Morse taper connection to the abutment (Arcsys-FGM-Brazil) (5.
Aim: The aim of this study was to evaluate the influence of different concentrations of two photoinitiators and one co-initiator on the flexural strength (FS) and elastic modulus (E) of experimental resin cements.
Materials And Methods: A mixture containing BisGMA, TEGDMA, and barium-aluminum-silicate (BaAlSi) and silanized colloidal silica (SiO) filler particles was prepared with two photoinitiators, viz. camphorquinone (CQ) and bisacylphosphine oxide (BAPO).
The aim of this study was to evaluate the effect of different glass fiber posts (GFPs) diameters on the push-out bond strength to dentin. Forty unirradicular human teeth were endodontically treated and used for cementation of GFPs (White Post DC, FGM) with different diameters (n=10): P1 - ø 1.6 mm coronal x 0.
View Article and Find Full Text PDFObjeticve: The aim of this study was to develop a composite material with antibacterial activity using MMT loaded with clorhexidine (CHX). For that it was used a BisGMA/TEGDMA matrix and added low concentration of MMT/CHX. The aim was to evaluate the drug release capacity of MMT, and not to provide reinforcement.
View Article and Find Full Text PDFObjective: To evaluate the shear bond strength between different artificial teeth and denture base polymerized by two polymerization methods submitted to thermocycling.
Materials And Methods: Two acrylic resins were selected according to the polymerization method (water-bath and microwave), and four different artificial teeth (Biotone, Dentsply; Trilux, Vipi Dent; Premium 8, Heraeus Kulzer; Soluut PX, Yamahachi) were also tested. The polymerization of the acrylic resin was performed by using conventional cycle (8 h at 74°C) in water-bath and using two cycles (20 min at 270 W + 5 min at 360 W) by the microwave method.
The aim in this study was to evaluate the influence of different ratio of camphorquinone/tertiary amine concentration on the flexural strength (FS), elastic modulus (EM), degree of conversion (DC), yellowing (YL), water sorption (WS) and water solubility (WSL) of experimental composites. Thus, acrylate blends were prepared with different camphorquinone (CQ) and amine (DABE) concentrations and ratios by weight: (CQ/DABE%): 0.4/0.
View Article and Find Full Text PDFObjective: To evaluate the influence of phenyl-propanedione on yellowing and chemical-mechanical properties of experimental resin-based materials photoactivated using different light curing units (LCUs).
Material And Methods: Experimental resin-based materials with the same organic matrix (60:40 wt% BisGMA:TEGDMA) were mechanically blended using a centrifugal mixing device. To this blend, different photoinitiator systems were added in equimolar concentrations with aliphatic amine doubled by wt%: 0.
This study evaluated the bond strength (BS) of experimental resin cements formulated with different photoinitiators when activated by two kinds of light-curing units (LCUs) through a ceramic material. Seven resin blends with different camphorquinone (CQ) and/or phenylpropanedione (PPD) concentrations (weight) were prepared: C5: 0.5% CQ; C8: 0.
View Article and Find Full Text PDF: The aim of this study was to evaluate the Knoop hardness number (KHN) of methacrylate (MC) and silorane (SC) composites after being submitted to erosion and abrasion processes. : Forty samples were made with each composite: MC and SC. The samples were divided into eight groups ( = 10) according to the type of composite (G1-G4, MC; G5-G8, SC) and the beverages involved in the erosion process (G1 and G5 - Control (C), without erosion, with abrasion; G2 and G6 - Orange Juice (OJ), abrasion; G3 and G7 - Smirnoff Ice® (SI), abrasion; G4 and G8 - Gatorade® (GA), abrasion).
View Article and Find Full Text PDFObjective: The objective of this study was to compare the torque and detorque values of screw intermediates of external hexagon, internal hexagon, and Morse taper implants in single restorations before and after mechanical cycling.
Materials And Methods: The study sample was divided into three groups (n = 10) as follows: group EH - external hexagon implant, group IH - internal hexagon implant, and group MT - Morse taper implant. Universal abutments were screwed on the implants, and metal crowns were cemented onto the abutment.
Teeth with vertical root fracture (VRF) have complete or incomplete fractures that begin in the root and extend toward the occlusal surface. The most frequent causes of VRF originate from physical trauma, occlusal prematurity, inadequate endodontic treatment, and iatrogenic causes. Diagnose is difficult and delay can cause stomatognathic system problem.
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