Physicochemical properties of flowable composites using isobornyl methacrylate as diluent monomer.

Objective: this study sought to evaluate the effect of isobornyl methacrylate (IBOMA) as a diluent monomer on the physicochemical properties of experimental flowable resin composites.

Methodology: the organic resin matrix of a modal flowable resin composite was formulated with 50 wt.% of bisphenol-A-glycidyl methacrylate (Bis-GMA) and 50 wt.

Effect of adding arginine at different concentrations to experimental orthodontic resins: an in vitro study.

The aim of this study was to assess the effect of adding arginine at different concentrations to commercial and experimental orthodontic resins on shear bond strength (SBS), as well as on the antimicrobial activity of arginine against S. mutans. Metal brackets were bonded onto the surface of 120 bovine incisors using Transbond, OrthoCem, and an experimental resin (ER), adding 0, 2.

Stability of the Dentin-Bonded Interface Using Self-Etching Adhesive Containing Diacrylamide after Bacterial Challenge.

Acrylamides are hydrolytically stable at pH lower than 2, and were shown to preserve bonded interface integrity with two-step, total etch adhesives. The objective of this study was to leverage those two characteristics in self-etching primers containing the acidic monomer 10-MDP and test the microtensile bond strength before and after incubation with incubation. Acidic primers (10 wt % 10-methacryloyloxydecyl dihydrogen phosphate─10-MDP; 45 wt % ,-diethyl-1,3-bis(acrylamido)propane─DEBAAP, or 2-hydroxyethyl methacrylate─HEMA; 45 wt %, glycerol-dimethacrylate─GDMA) and adhesives (DEBAAP or HEMA/10-MDP/UDMA 45/10/45 wt %) were made polymerizable by the addition of 0.

Effect of hydrofluoric acid concentration and aging on the bond strength ceramics to a resin cement.

This study evaluated the influence of hydrofluoric acid (HF) concentration and thermal cycling on the microshear bond strength (µSBS) of a resin luting agent to IPS e.max® CAD and Rosetta® SM. Ceramic specimens (12.

Cellulose acetate scaffold coated with a hydroxyapatite/graphene oxide nanocomposite for application in tissue engineering.

The objective of this study was to synthesize and characterize porous Cellulose Acetate (CA) scaffolds using the electrospinning technique and functionalize the surface of the scaffolds obtained through the dip-coating method with a Hydroxyapatite (HA) nanocomposite and varying concentrations of graphene oxide (GO) for application in tissue engineering regeneration techniques. The scaffolds were divided into four distinct groups based on their composition: 1) CA scaffolds; 2) CAHAC scaffolds; 3) CAHAGOC 1.0% scaffolds; 4) CAHAGOC 1.

Multi-acrylamides improve bond stability through collagen reinforcement under physiological conditions.

Objectives: Acrylamides were shown to significantly improve bonding stability in adhesive restorations, but the reinforcement mechanism has not been fully elucidated. We tested the hypothesis that hydrogen bonding reinforcement of the collagen network (with secondary or tertiary acrylamides), as well as degree of crosslinking of the polymer network (with di- or tri-functional acrylamides), can be two of the factors at play.

Methods: Two-step total etch adhesives comprising UDMA (60 wt%) and 40 wt% of: TAAEA, TMAAEA (secondary, tertiary tri-acrylamides), BAAP, DEBAAP (secondary, tertiary di-acrylamides) or HEMA (mono-methacrylate - control) were formulated.

Surface treatments of the zirconia-reinforced lithium disilicate ceramic in the adhesion to the resin cement.

This study verified the effect of surface treatments of the zirconia-reinforced lithium disilicate ceramic bonded to resin cement. Ceramic blocks were divided according to treatments (n=10): FA+SRX (Fluoric acid + silane RX), FA+MDP (Fluoric acid + MDP), FA+SCF+MDP (Fluoric acid + silane CF + MDP), FA+MEP (Fluoric acid + MEP), and MEP (Self-etch primer). Resin cement cylinders were made in the ceramic blocks, photoactivated with 1,200 mW/cm² for 40s, stored in water at 37°C for 24h, and evaluated by the microshear strength test, optical failure descriptive analysis (%), surface characterization (SEM) and contact angle (Goniometer).

Preheated acid associated with silane and electric current in the adhesion of the resin cement to ceramic.

This study verified the effect of the combination of preheated hydrofluoric acid/silane/electric current in the adhesion of the resin cement to ceramic. IPS E.max Press ceramic discs embedded in PVC rigid tubes were divided into four groups associating preheated hydrofluoric acid and silane applied with electrical current (n=10): Ha+S (Heated acid + silane); Ha+S+Ec (Heated acid + silane + electrical current); A+S (Acid + silane) and A+S+Ec (Acid + silano + electrical current).

Effect of Ceramic Thickness on the Bond Strength to Resin-Luting Agents before and after Thermal Cycling.

This study investigated microshear bond strength (µSBS) of two (2) dual-cured resin-luting agents (RelyX™ Ultimate and RelyX™ U200) when photoactivated through varying thicknesses of lithium disilicate, with or without thermal cycling. Discs of IPS e.max Press of 0.

Evaluation of mechanical properties and morphology of miniscrews Ti6Al4V cold worked versus annealed in artificial bones.

Purpose: This study aimed to evaluate the influence of different manufacturing procedures (Eli annealed - hot work versus cold worked - cold work) of the raw material under mechanical properties and morphological characteristics of orthodontic miniscrews (MS).

Material And Methods: Thirty MS were randomly separated into 3 types (n=10) according to manufacturer and manufacturing process of the raw material: type A - SIN® annealed (control group); type B - Dentfix® annealed; and, type C - Dentfix® cold worked. MI were inserted in artificial bone blocks, through the manufacturer's specific manual key attached to the digital torquemeter stabilized via custom device.

Deflection of tandem archwire in a specific self-ligating metal bracket system: an in vitro study.

The aim of this study was to quantify the force exerted by tandem archwires in a specific system of passive self-ligating bracket. Forty-eight thermo-activated nickel-titanium orthodontic archwires were separated into four groups (n = 12): G1 - two .014" + .

Curing profile and marginal gap formation using a liner containing long-wavelength-absorbing photoinitiator: an in vitro study.

The aim was to evaluate the marginal-gap formation and curing profile of a new restorative technique using a liner with long-wavelength-absorbing photoinitiator (LWAP). Box-shaped preparations (6 mm × 4 mm × 4 mm) were made in third molars. All samples were treated with Clearfill SE Bond and divided into 4 groups (n = 5), according to restorative technique used: (1) incremental technique (INC-Technique); (2) camphorquinone-based liner (CQ-Liner) + bulk-fill resin composite; (3) LWAP-based liner (LWAP-Liner) + bulk-fill resin composite; and (4) bulk-fill technique without liner (BF-Technique).

Chitosan/Xanthan/Hydroxyapatite-graphene oxide porous scaffold associated with mesenchymal stem cells for dentin-pulp complex regeneration.

The aim of this paper was to synthesize and characterize polymeric scaffolds of Chitosan/Xanthan/Hydroxyapatite-Graphene Oxide nanocomposite associated with mesenchymal stem cells for regenerative dentistry application. The chitosan-xanthan gum (CX) complex was associated with Hydroxyapatite-Graphene Oxide (HA-GO) nanocomposite with different Graphene Oxides (GO) concentration (0.5 wt%; 1.

Delayed light-curing of dual-cure bulk-fill composites on internal adaptation and depth of cure.

Objective: To evaluate the effect of delayed light-curing of dual-cure bulk-fill composites on internal adaptation and microhardness (KHN) in depth.

Materials And Methods: Bulk-fill composites were placed in 35 box-shaped preparations and cured according to the following protocols (n = 5): Filtek Bulk-Fill light-cured immediately after insertion (FBF); Bulk-EZ light-cured immediately after insertion (BEZ-I); Bulk-EZ light-cured 90 s after insertion (BEZ-DP); Bulk-EZ self-cured (BEZ-SC); HyperFIL light-cured immediately after insertion (HF-I); HyperFIL light-cured 90 s after insertion (HF-DP); HyperFIL self-cured (HF-SC). After 24 h, the samples were axially sectioned, and the internal adaptation was evaluated using replicas under a scanning electron microscope.

Effect of horizontal slot of maxillary canines' brackets with varying wire angulations - An in vitro study.

A new device was developed to enable the visualization and measurement of canine angulation while at the same time visualizing and measuring the force transmitted to adjacent teeth. This study aimed to evaluate the mesiodistal tilt angle of the upper canine brackets, the wire deflection, and its effects on adjacent teeth with five different slot designs of upper canines. Wires (0.

Do cone-beam computed tomography low-dose protocols affect the evaluation of the temporomandibular joint?

Background: There is no established acquisition protocol based on scientific evidence for the acquisition of cone-beam computed tomography (CBCT) exams to evaluate the temporomandibular joint (TMJ).

Objectives: To evaluate the influence of acquisition protocols and jaw positioning on the diagnostic accuracy of TMJ condylar morphological alterations (CMA), dimension, position and excursion.

Methods: Thirty-six TMJs on 18 dry skulls were imaged using a CBCT unit (OP300 Maxio, Instrumentarium, Tuusula, Finland) at two exposure settings (4.

Chitosan/Xanthan membrane containing hydroxyapatite/Graphene oxide nanocomposite for guided bone regeneration.

Objective: To develop a chitosan-xanthan (CX) membrane associated with Hydroxyapatite (HA) and different concentrations of graphene oxide (GO).

Methodology: The CX complex was associated with the hydroxyapatite-graphene oxide (HAGO) nanocomposite in different concentrations. The experimental groups were:1) CX; 2) Chitosan-Xanthan/Hydroxyapatite (CXHA); 3) Chitosan-Xanthan/Hydroxyapatite-Graphene Oxide 0.

Comparison of the shear bond strength between metal brackets and Transbond™ XT, Filtek™ Z250 and Filtek™ Z350 before and after gastroesophageal reflux: An in vitro study.

Purpose: To evaluate in vitro the effect of gastroesophageal reflux, before and after bonding of metal brackets on composite resin surface.

Materials And Methods: Two hundred and ten resin discs were divided into 5 groups (n=42), according to the time and medium of storage: 24h, 7- and -30 days in artificial saliva (AS) and hydrochloric acid (HCL). Twelve samples from each group were submitted to surface roughness analysis (n=60).

Effect of light attenuation through veneers on bond strength of adhesives with photoinitiator combinations.

This study aimed to evaluate the effect of light attenuation through ceramic veneers and resin cement on degree of conversion (DC), cohesive strength (CS), and microshear bond strength (μSBS) of experimental adhesive systems. Experimental etch-and-rinse and self-etch adhesives were combined with different ratios of camphorquinone (CQ) and diphenyl(2,4,6-trimethylbenzoyl) phosphine oxide (TPO) photoinitiators: CQ-only; 3CQ:1TPO; 1CQ:1TPO; 1CQ:3TPO and TPO-only. Square-shaped ceramic veneer (IPS Empress Esthetic, Ivoclar Vivadent) (n = 10; 10mm long x 10mm wide x 0.

Comparison of the friction forces delivered by different elastomeric patterns and metal ligature on conventional metal brackets with a NiTi arch wire versus a self-ligating system: An in vitro study.

Objectives: The aim of this study was to measure the frictional resistance of different types of ligatures used on conventional and self-ligating brackets.

Materials And Methods: Monoblock (conventional) and Portia (self-ligating) brackets were used and the archwire used was nickel-titanium. On conventional brackets the ligatures tested were the Elastomeric type and steel 0.

Comparison of the physico-chemical impact of chlorhexidine and silver nanoparticles on orthodontic appliances made with laser and silver solder: An in vitro study.

Objective: The aim of this study was to evaluate the physical-chemical changes in orthodontic devices made with laser and silver solder after immersion in different antiseptic solutions.

Methods: Wire/band assemblies were fabricated using different types of solders (silver and laser). The devices were immersed in different antimicrobial solutions (chlorhexidine - CHX 0.

Do dual-cure bulk-fill resin composites reduce gaps and improve depth of cure.

This in vitro study aimed to evaluate the gaps length and depth of cure of dual-cure bulk-fill resin composites inserted in box-shaped preparations. Box-shaped preparations (4 mm deep) were made in fifteen human third-molars and divided into three groups according to the resin composites (n=5): Dual-cure bulk-fill BulkEZ (BEZ); Dual-cure bulk-fill HyperFIL (HF); and Tetric Evoceram Bulk-fill (TETRIC), as control. Gaps length (%) was evaluated in tooth-restoration interface with micro-computed tomography (µCT).

Force Degradation of Elastomeric Chains after Storage Time and Mechanical Brushing.

The purpose of this in vitro study was to evaluate the force decrease of different elastomeric chains after different times: initial, 10 minutes, 1 day, 28 days and after mechanical brushing. Twenty orthodontic elastomeric chains segments were utilized for each commercial brand. Initially, the elastomeric chain of 15mm long were immediate stretched up to 20 mm in an Instron and the force was measured in gf.

CHX Stabilizes the Resin/demineralized Dentin Interface.

The aim of this study was to evaluate the effect of 2% chlorhexidine digluconate (CHX) on microtensile bond strength (µTBS) between an adhesive system and under 3 dentin conditions. For that, this study evaluated the adhesive interface at initial, after 6 months and 1 year of storage. Forty-eight human third molars were prepared and randomly divided into 3 groups, according to dentin substrates: sound dentin (Sd), caries-infected dentin (Ci) and caries-affected dentin (Ca).

Effect of lithium disilicate ceramic thickness, shade and translucency on transmitted irradiance and knoop microhardness of a light cured luting resin cement.

This in vitro study evaluates the influence of pressed lithium disilicate thickness, shade and translucency on the transmitted irradiance and the Knoop microhardness (KHN) of a light-cured resin cement at two depths. One hundred and thirty-five ceramic discs of IPS e.max Press (Ivoclar Vivadent) were fabricated and divided into twenty-seven groups (n = 5) according to the association between translucency: HT (hight translucency), LT (low translucency), and MO (medium opacity); shade: BL2, A1 and A3.