Semidirect posterior composite restorations with a flexible die technique: A case series.

Background And Overview: Besides indirect use in the laboratory and direct use for restorations, composites can be used in semidirect procedures. The authors describe the semidirect composite restoration technique by using a flexible die for large lesions in posterior teeth.

Case Description: The authors present illustrations of the clinical steps and the outcomes immediately after the procedures.

Influence of previous acid etching on bond strength of universal adhesives to enamel and dentin.

The objective of this study was to evaluate the effect of acid pretreatment on the bond strength of composite resin bonded to enamel and dentin with 2 different universal self-etching adhesives. The null hypothesis was that the acid treatment performed prior to adhesive application would not significantly change the bond strength to enamel or dentin for either universal adhesive tested. A sample of 112 bovine incisors were selected and embedded in acrylic resin.

Effects of Contamination by Hemostatic Agents and Use of Cleaning Agent on Etch-and-Rinse Dentin Bond Strength.

The aim of this study was to evaluate the influence of contamination by hemostatic agents and rinsing with chlorhexidine on bond strength between dentin and resin composite. Ninety-six bovine teeth were sectioned to expose a flat dentin surface area. A standardized cavity with 2.

Longitudinal Effect of Surface Treatments Modified by NaOCl-Induced Deproteinization and Nd:YAG Laser on Dentin Permeability.

Objective: The purpose of this study was to evaluate dentin permeability after dentin hypersensitivity treatments: fluoride, adhesive system, and collagen deproteinization with and without Nd:YAG laser exposure, and after erosive and abrasive challenges.

Materials And Methods: Dentin permeability was assessed by measuring dentinal fluid flow using a permeability device. Eighty bovine dentin specimens (6 mm diameter/1 mm thickness) had permeability measured in the presence of the smear layer and after removal of the smear layer by ethylenediaminetetraacetic acid (EDTA).

Influence of whitening gel application protocol on dental color change.

Objectives: To evaluate the influence of different whitening protocols on the efficacy of 35% hydrogen peroxide (HP) tooth whitening and gel pH and concentration.

Material And Methods: Eighty-four enamel/dentin discs from bovine incisors were used. The baseline color was measured with a spectrophotometer.

Grander system: a new technology to reduce surface tension of adhesive systems in dentistry.

Background: Reduced surface tension of liquids results in higher surface wetting ability and diffusivity by the substrate.

Objectives: The objective of this study was to evaluate the influence of the Grander Technology in reducing the surface tension of adhesive systems.

Methods: Two adhesive systems (self-etch and total-etch) were modified by physical contact with the Grander system Flexible unit to revitalize water, for 48 h.

Influence of concentration and activation on hydrogen peroxide diffusion through dental tissues in vitro.

This study evaluated the effect of physical and chemical activation on the diffusion time of different concentrations of hydrogen peroxide (HP) bleaching agents through enamel and dentin. One hundred and twenty bovine cylindrical specimens were divided into six groups (n = 20): 20% HP; 20% HP with light activation; 20% HP with manganese gluconate; 35% HP; 35% HP with light activation; and 35% HP with manganese gluconate. The specimens were fixed over transparent epoxy wells with internal cavities to simulate a pulpal chamber.

Direct spectrometry: a new alternative for measuring the fluorescence of composite resins and dental tissues.

The aim of this study was to evaluate the fluorescence intensity of different composite resins and compare those values with the fluorescence intensity of dental tissues. Different composite resins were used to make 10 discs (2 mm in depth and 4 mm in diameter) of each brand, divided into groups: 1) Z (Filtek Z350, 3M ESPE), 2) ES (Esthet-X, Dentsply), 3) A (Amelogen Plus, Ultradent), 4) DVS (Durafill-VS, Heraeus Kulzer) with 2 mm composite resin for enamel (A2), 5) OES ([Esthet-X] opaque-OA [1 mm] + enamel-A2 [1 mm]); 6) ODVSI ([Charisma-Opal/Durafill-VSI], opaque-OM (1 mm) + translucent [1mm]), and 7) DVSI ([Durafill- VSI] translucent [2 mm]). Dental tissue specimens were obtained from human anterior teeth cut in a mesiodistal direction to obtain enamel, dentin, and enamel/dentin samples (2 mm).

Influence of Nd:YAG laser on the bond strength of self-etching and conventional adhesive systems to dental hard tissues.

Purpose: The aim of this study was to investigate the influence of Nd:YAG laser on the shear bond strength to enamel and dentin of total and self-etch adhesives when the laser was applied over the adhesives, before they were photopolymerized, in an attempt to create a new bonding layer by dentin-adhesive melting.

Material And Methods: One-hundred twenty bovine incisors were ground to obtain flat surfaces. Specimens were divided into two substrate groups (n=60): substrate E (enamel) and substrate D (dentin).

Effect of calcium hydroxide on ph changes of the external medium after intracoronal bleaching.

Aim: This in vitro study evaluated the effect of calcium hydroxide on pH changes of the external medium after intracoronal bleaching.

Materials And Methods: A total of 50 extracted human premolars were prepared and filled with gutta-percha and endodontic sealer. The teeth were randomly divided into five groups according to the bleaching agents employed: (a) Sterile cotton pellet with distilled water (control group); (b) sodium perborate and distilled water; (c) sodium perborate and 10% carbamide peroxide; (d) sodium perborate and 35% hydrogen peroxide; (e) 35% hydrogen peroxide.

Temperature variation caused by high-intensity LED curing lights in bovine dentin.

This study sought to evaluate the temperature variations in bovine dentin when cured with high-intensity LED appliances and quartz-tungsten-halogen (QTH) appliances. Forty-five slices of bovine dentin (0.7 mm thick) were divided into three groups.

Polymerization efficiency of high-intensity LEDs with different exposure times.

This study compared two high-intensity light-emitting diode (LED) appliances to a quartz-halogen-tungsten (QTH) appliance and measured their ability to polymerize resin composite efficiently. Eighty-four test specimens (2 mm x 5 mm) were made of resin composite and exposed to one of the two LED appliances for 10, 20, or 40 seconds; the QTH appliance was used as a control group for 40 seconds. It was concluded that using the high-intensity LEDs for 20 seconds produced microhardness similar to that produced by using the QTH appliance for 40 seconds, but the high intensity LEDs did not improve depth of cure.