Fracture strength and hybrid layer formation of endodontically-treated teeth after dental bleaching photoactivated with violet LED.

Objective: To evaluate in vitro the effect of dental bleaching using high concentration hydrogen peroxide (HP) photoactivated with violet LED on fracture strength and hybrid layer formation.

Methods: forty endodontically-treated bovine teeth were randomized into four groups (n = 10): C - Control, HP - 35% hydrogen peroxide, HP-BL - 35% hydrogen peroxide photoactivated with blue LED, HP-VL - 35% hydrogen peroxide photoactivated with violet LED. Three bleaching sessions with an interval of 7 days between them were performed.

Etch-and-rinse versus self-etch strategy of a universal adhesive in different application methods at the bonding interface of fiber post cementation.

Objective: To evaluate the effect of etch-and-rinse (ER) versus self-etch (SE) strategies of a universal adhesive applied with a manual brush (MB) or rotary brush (RB) on the bonding interface of fiber post cementation.

Methods: Forty bovine incisor roots were prepared and divided into four groups according to the methods of application and strategy of universal adhesive use (MB-ER, RB-ER, MB-SE and RB-SE). After 6 months, specimens from different thirds of the post space were evaluated of push-out strength, analysis of adhesive failure patterns, and extent of tags.

Effect of non-vital tooth bleaching photoactivated with blue or violet LED on color and microhardness.

Background: To evaluate the efficacy of dental bleaching protocols using 35% hydrogen peroxide photoactivated with violet LED on color and microhardness of endodontically treated teeth.

Methods: Forty specimens were selected and randomized into 4 groups (n = 10): C - Control, HP - 35% hydrogen peroxide, HP + BL - 35% hydrogen peroxide + blue LED, HP + VL - 35% hydrogen peroxide + violet LED. Three bleaching sessions were performed for each group.

Effectiveness and color stability of non-vital dental bleaching photoactivated by violet LED on blood-stained teeth.

Background: Few studies have investigated the effect of violet LED irradiation associated or not with bleaching agents on blood-stained teeth. This in vitro study aimed to evaluate the whitening efficacy and color stability of non-vital dental bleaching using 35% hydrogen peroxide (HP) photoactivated with violet LED (VL) compared to 35% HP alone and 35% HP photoactivated with blue LED (BL).

Methods: Fifty bovine dental crowns were used to obtain specimens of 5 × 5 × 2 mm.

Sealing of restorations with marginal defects does not affect their longevity.

Purpose: To evaluate sealed amalgam and resin-based composite restorations after 12 years to determine whether sealing minor defects (micro-repairs) enhanced the longevity of restorations.

Methods: 34 subjects aged 18-80 were recruited. This sample group underwent 137 restorations, including 51 resin-based composite (RC) and 86 amalgam (AM) restorations.

Effects of Photodynamic Therapy on the Adhesive Interface of Fiber Posts Cementation Protocols.

Introduction: The aim of this study was to evaluate the effects of photodynamic therapy (PDT) on the bond strength and dentinal penetrability of cementation protocols using conventional resin cement (Relyx ARC; 3M ESPE, St Paul, MN) or self-adhesive (Relyx U200, 3M ESPE) after the glass fiber post cementation.

Methods: Forty human canine roots were endodontically treated and prepared for a fiber post. The roots were divided into 4 groups according to the cementation protocol and PDT use: conventional cement (CC), Relyx ARC; self-adhesive cement (SAC), Relyx U200 cement; PDT/CC, PDT + Relyx ARC; and PDT/SAC, PDT + Relyx U200.

Differential Diagnosis and Treatment Proposal for Acute Endodontic Infection.

The objective of this study was to describe the main lesions that simulate clinically and propose a treatment protocol for acute endodontic infection. Signs and clinical symptoms of periodontal abscess, gingival abscess, odontoma, herpes simplex, pericoronitis, acute pulpitis and necrotizing ulcerative gingivitis/periodontitis (NUG/NUP) were described and compared with acute endodontic infections. A treatment protocol was described by optimizing the procedures in access cavity, microbial decontamination and detoxification of the root canal, apical debridement, intracanal and systemic medication and surgical drainage procedures.

Marginal adaptation of class V restorations with current-generation dentin-bonding agents: effect of different dentin surface treatments.

This study sought to assess the use of chlorhexidine with several excipients as a dentin surface treatment and its effect on marginal adaptation of class V restorations with current-generation dentin bonding agents. A total of 120 human third molars were selected and allocated into 12 groups, with standardized buccal class V restorations randomly divided into preconditioned dentin rinsed with: water; water + chlorhexidine; ethanol; or ethanol + chlorhexidine. After rinsing of dentin (previously conditioned with 35% phosphoric acid) with the test solutions, the Adper single bond 2, prime and bond 2.

Correction of Malpositioned Implants through Periodontal Surgery and Prosthetic Rehabilitation Using Angled Abutment.

When dental implants are malpositioned in relation to the adjacent teeth and alveolar bone or in an excessive buccal or lingual position, the final prosthesis rehabilitation impairs the peri-implant health of the gingival tissues and the aesthetics of the patient. Thus, the purpose of this case was to report and discuss a multidisciplinary protocol for the treatment of a compromised maxillary tooth in a patient with an abscess in his right central incisor due to an excessive buccal implant position. The patient presented with an implant-supported provisional restoration on his right maxillary central incisor and a traumatic injury in his left central incisor.

Degree of conversion and hardness of two different systems of the Vitrebond™ glass ionomer cement light cured with blue LED.

This study investigated the physicochemical properties of the new formulation of the glass ionomer cements through hardness test and degree of conversion by infrared spectroscopy (FTIR). Forty specimens (n = 40) were made in a metallic mold (4 mm diameter x 2 mm thickness) with two resin-modified glass ionomer cements, Vitrebond™ and Vitrebond™ Plus (3M/ ESPE). Each specimen was light cured with blue LED with power density of 500 mW/cm(2) during 30 s.

Degree of conversion of polymer-matrix composite assessed by FTIR analysis.

Aims And Objectives: The behavior of polymer-matrix composite is dependent on the degree of conversion. The aim of this study was to evaluate the degree of conversion of two resin cements following storage at 37°C immediately, 24 and 48 hours, and 7 days after light-curing by FTIR analysis.

Materials And Methods: The specimens were made in a metallic mold and cured with blue LED with power density of 500 mW/ cm(2) for 30 seconds.

Evaluation of degree of conversion and hardness of dental composites photo-activated with different light guide tips.

Objective: The aim of this study was to evaluate the degree of conversion and hardness of different composite resins, photo-activated for 40 s with two different light guide tips, fiber optic and polymer.

Methods: Five specimens were made for each group evaluated. The percentage of unreacted carbon double bonds (% C═C) was determined from the ratio of absorbance intensities of aliphatic C═C (peak at 1637 cm(-1)) against internal standard before and after curing of the specimen: aromatic C-C (peak at 1610 cm(-1)).

Anterior restorations in bleached teeth: difficulty establishing the color after bleaching.

It is becoming more common for patients to look for cosmetic procedures in dental offices. The search for lost or desired esthetics by patients is increasingly frequent and the professional must be able to meet this demand. To do this, dentists not only need to return the tooth back to its normal functioning state but also promote esthetic excellence.

CIE L*a*b*: comparison of digital images obtained photographically by manual and automatic modes.

The aim of this study was to analyze the color alterations performed by the CIE L*a*b* system in the digital imaging of shade guide tabs, which were obtained photographically according to the automatic and manual modes. This study also sought to examine the observers' agreement in quantifying the coordinates. Four Vita Lumin Vaccum shade guide tabs were used: A3.

Using the self-etch adhesives in anterior restoration.

With the arrival of self-etch adhesives systems, there has been a rise in interest among clinicians, making it imperative for health professionals to have knowledge of the properties, characteristics, the association as well as the dental structures of these materials, in order to select them and use them correctly. The self-etch adhesive systems show good values of bond strength, microleakage and performance, and have therefore become an option in direct adhesive restorations. In the regard, this case study aims to describe the technique involving the use of selfetch adhesives system for direct restoration of anterior teeth.

Tissue response to experimental dental cements prepared from a modified powder glass composition.

The present work seeks to evaluate the biocompatibility of experimental glass ionomer cements (GIC) prepared from niobium-calcium fluoro-alumino-silicate glass powder and two commercial GICs. The GICs were implanted into the subcutaneous connective tissue of sixty rats. The rats were sacrificed during four varying time periods: 7, 15, 30, and 60 days and histopathological examinations were then performed.

Shear bond strength of repairs in porcelain conditioned with laser.

The aim of this study was to evaluate the shear bond strength of repairs in porcelain conditioned with laser. Sixty porcelain discs were made and six groups were formed (n = 10): G1: conditioning with laser with potency 760 mW; G2: conditioning with laser with potency 760 mW and application of 37% phosphoric acid for 15 s; G3: conditioning with laser with potency 900 mW; G4: conditioning with laser with potency 900 mW and application of 37% phosphoric acid for 15 s; G5: application of 37% phosphoric acid for 15 s (group control) and G6: application of 10% hydrofluoric acid for 2 min. The composite resin was insert of incremental layers at the porcelain surface aided with a metal matrix, and photoactivation for 20 s each increment.

Effect finishing and polishing procedures on the surface roughness of IPS Empress 2 ceramic.

Objective: To evaluate the surface roughness of IPS Empress 2 ceramic when treated with different finishing/polishing protocols.

Materials And Methods: Sixteen specimens of IPS Empress 2 ceramic were made from wax patterns obtained using a stainless steel split mold. The specimens were glazed (Stage 0-S0, control) and divided into two groups.

New approaches to dental occlusion: a literature update.

Because the study of occlusion is a basic area in dentistry, its components, physiology and integration with the stomatognathic system (SS) have been the subject of interest in the scientific literature. However, the focus given to this issue has changed substantially. Currently, new approaches have been proposed in order to update concepts and to demonstrate the full integration and functionality of this system within the human body.

Fracture strength of flared bovine roots restored with different intraradicular posts.

Objective: The aim of this study was to evaluate the fracture strength and failure mode of flared bovine roots restored with different intraradicular posts.

Material And Methods: Fifty bovine incisors with similar dimensions were selected and their roots were flared until 1.0 mm of dentin wall remained.

Effect of four bleaching regimens on color changes and microhardness of dental nanofilled composite.

Objective. The purpose of this study was to compare the color changes and microhardness of a nanocomposite after four bleaching regimens. Materials.