Effect of 2% chlorhexidine digluconate on the bond strength to normal versus caries-affected dentin.

This study evaluated the effect of 2% chlorhexidine digluconate (CHX) used as a therapeutic primer on the long-term bond strengths of two etch-and-rinse adhesives to normal (ND) and caries-affected (CAD) dentin. Forty extracted human molars with coronal carious lesions, surrounded by normal dentin, were selected for this study. The flat surfaces of two types of dentin (ND and CAD) were prepared with a water-cooled high-speed diamond disc, then acid-etched, rinsed and air-dried.

Cytotoxic effects of different concentrations of a carbamide peroxide bleaching gel on odontoblast-like cells MDPC-23.

This study evaluated the cytotoxic effects of a carbamide peroxide (CP) bleaching gel at different concentrations on odontoblast-like cells. Immortalized cells of the MDPC-23 cell line (30,000 cells/cm(2)) were incubated for 48 h. The bleaching gel was diluted in DMEM culture medium originating extracts with different CP concentrations.

Effect of long-term water storage on etch-and-rinse and self-etching resin-dentin bond strengths.

This study sought to evaluate the long-term bond strength of etch-and-rinse and self-etch adhesive systems to dentin after one year of water storage. Crown fragments from the buccal surface of extracted bovine incisors were ground flat to expose dentin surfaces. Four etch-and-rinse and two self-etch bonding agents were used according to manufacturers' instructions.

In vitro evaluation of the effectiveness of bleaching agents activated by different light sources.

Purpose: This study evaluated the efficacy of tooth whitening and color stability at different time periods after treatment.

Materials And Methods: Blocks obtained from human molars were divided into 15 groups (n = 5) by bleaching agents: 35% hydrogen peroxide (Whiteness HP and Opalescence Xtra) and 37% carbamide peroxide (Whiteness Super); and light sources: halogen lamp and plasma arc lamp (bleach mode), LED/diode laser, argon laser, and no light source. The efficacy of bleaching was measured using a spectrophotometer.

Validity of caries detection on occlusal surfaces and treatment decisions based on results from multiple caries-detection methods.

The aim of this in vitro study was to evaluate whether having results available from multiple detection methods influences dentist's treatment decisions for incipient caries lesions on occlusal surfaces. The occlusal surface of 96 extracted permanent molars without frank cavitation was examined by three examiners initially by visual examination alone, following which they chose one of three treatment options: (i) no treatment, (ii) preventive or non-invasive treatment (sealants), and (iii) invasive treatment. Four weeks later the examiners again selected one of the three treatment options for the surfaces, but this time were able to refer to the results from additional caries-detection methods [bitewing radiographs, electric conductance measurement (ECM), quantitative light fluorescence (QLF), and DIAGNOdent] that had been performed in the interim time.

Thermal variations in the pulp chamber associated with composite insertion techniques and light-curing methods.

Aim: The aim of this study was to investigate the effect of different incremental insertion techniques, photoactivation, and restorative phases on thermal variations occurring during the polymerization of Filtek Z250 composite resin.

Methods And Materials: The experiment was conducted using 90 bovine incisor teeth. The teeth were randomly assigned to three groups according to the technique used for photoactivation with a halogen light (continuous, soft-start, or intermittent).

The effect of the presence and presentation mode of co-initiators on the microtensile bond strength of dual-cured adhesive systems used in indirect restorations.

This study compared the microtensile bond strength (microTBS) of indirect resin composite restorations to dentin when fifth-generation adhesive systems were either light-activated or left in the uncured state prior to cementation. The systems used in this study were Prime&Bond NT (NT-Dentsply) and Excite (EX-Ivoclar-Vivadent) or their dual-cured versions containing co-initiators with different presentation modes (as solution or salts) Prime&Bond NT Dual-cure (NTD-Dentsply) and Excite DSC (DSC-Ivoclar Vivadent). The bonding agents were applied to the flattened occlusal dentin surfaces of 40 human third molars according to the manufacturers' instructions and were light-activated (XL3000/3M ESPE) for 10 seconds (LP) or left in the uncured state (SP).

Effect of curing lights and bleaching agents on physical properties of a hybrid composite resin.

Unlabelled: The aim of this in vitro study was to evaluate the microhardness (MH) and diametral tensile strength (DTS) of a minifill hybrid composite (Filtek Z250, 3M ESPE), polymerized with halogen lamp or second generation light-emitting diode (LED), submitted to different bleaching agents. Composite resin specimens were randomly polymerized according to experimental groups (halogen, 550 mW/cm(2)/20 seconds; LED, 550 mW/cm(2)/25 seconds) and subdivided into three subgroups (N=8): A, without bleaching (control); H, 35% hydrogen peroxide; and C, 16% carbamide peroxide. After that, the MH test and DTS test were performed.

Transdental photo-activation technique: hardness and marginal adaptation of composite restorations using different light sources.

This study investigated the influence of different light sources associated with a transdental photoactivation technique on the marginal adaptation and hardness of composite restorations. Cavities (3 mm wide x 3 mm long x 1.5 mm in deep) were prepared on flattened bovine dentin and filled with Z250 composite (3M ESPE).

Effect of composite resin polymerization modes on temperature rise in human dentin of different thicknesses: an in vitro study.

The aim of this in vitro study was to evaluate the effect of different polymerization modes on temperature rise in human dentin of different thicknesses, and to evaluate the relation between dentin thickness and temperature rise (TR). For this purpose, 60 specimens were assigned into 20 groups (n = 3): five polymerization modes (1-conventional; 2-soft-start; 3-high intensity; 4-ramp cure: progressive and high intensity; 5-high intensity with the tip of the light-curing unit at a distance of 1.3 cm for 10 s and the tip leaning on the sample) at four dentin thicknesses (0, 1, 2, 3 mm).

Effects of the solvent evaporation technique on the degree of conversion of one-bottle adhesive systems.

This study evaluated the effect of four methods of solvent evaporation on the degree of conversion (DC) of seven one-bottle adhesive systems: Excite (EX), ONE-STEP (OS), Optibond Solo Plus (OB), Prime&Bond 2.1 (PB), Prime&Bond NT (NT), Single Bond (SB) and Single Bond Plus (SP) using Fourier Transform Infrared Analysis (FTIR). Adhesive resins were: 1) applied to KBr pellet surfaces and left undisturbed for 30 seconds (condition 1), 2) left undisturbed for 30 seconds and air-dried with an air stream for 10 seconds (condition 2), 3) left undisturbed for 60 seconds (condition 3) and 4) left undisturbed for 60 seconds and air-dried for 10 seconds (condition 4) before curing.

Microhardness of different thicknesses of resin composite polymerized by conventional photocuring at different distances.

This in vitro study sought to evaluate the influence of photocuring modes and polymerization time on the microhardness of a hybrid composite resin. Sixty composite resin specimens were prepared at random and divided into 12 experimental groups (n=5), consisting of four curing tip distances (2.0 mm, 4.

Effects of 6 months of aging in water on hardness and surface roughness of two microhybrid dental composites.

Purpose: This study assessed the effect of 6 months of aging in water on surface roughness and surface/subsurface hardness of two microhybrid resin composites.

Materials And Methods: Filtek Z250 and Charisma were tested. Cylindrical specimens were obtained and stored in distilled water for 24 hours or 6 months, at 37 degrees C.

Effect of the CO2 laser combined with fluoridated products on the inhibition of enamel demineralization.

Aim: This in vitro study evaluated the combined effects of a 10.6 microm CO2 laser, fluoridated dentifrice, and mouthrinse on the reduction of lesion progression in carious human enamel.

Methods And Materials: Slabs of previously demineralized dental enamel were assigned to nine groups, either treated with/without a CO2 laser, with/without fluoridated dentifrice, and with/without fluoridated mouthrinse.

Membrane permeability properties of dental adhesive films.

This study evaluated the permeability properties of five experimental resin membranes that ranged from relatively hydrophobic to relatively hydrophilic to seal acid-etched dentin saturated with water or ethanol. The experimental resins (R1, R2, R3, R4, and R5) were evaluated as neat bonding agents or as solutions solvated with ethanol (70% resin/30% ethanol). The quality of dentin sealing by these experimental resins was expressed in terms of reflection coefficients calculated as the ratio of the effective osmotic pressure to the theoretical osmotic pressure of test solutions.

In vitro microTBS of one-bottle adhesive systems: sound versus artificially-created caries-affected dentin.

This in vitro study aimed to evaluate a pH-cycling model for simulation of caries-affected dentin (CAD) surfaces, by comparing the bond strength of etch-and-rinse adhesive systems on sound and artificially-created CAD. Dentin substrates with different mineral contents and morphological patterns were created by submitting buccal bovine dentin to the following treatments: (1) immersion in artificial saliva during the experimental period (sound dentin, SD), or (2) induction to a CAD condition by means of a dynamic pH-cycling model (8 cycles, demineralization for 3 h followed by mineralization for 45 h). The bond strength of Excite or Prime and Bond NT adhesive systems was assessed using the microtensile bond strength (microTBS) test.

Effect of light curing units on marginal adaptation and hardness of Class II composite resin restorations.

Aims: The aim of this study was to test the influence of different curing protocols on dentin marginal adaptation and the hardness of two composites.

Methods And Materials: Three light-curing-units (LCUs): Quartz-Tungsten-Halogen (QTH: 541 mW/cm2), Argon-Ion-Laser (AL: 277 mW/cm2), and Plasma-Arc-Curing (PAC: 1818 mW/cm2) and two composites FiltekZ250 (F) and Tetric Ceram HB (TC) were tested. Sixty standardized "vertical-slot-Class II-cavities" were prepared at the mesial surface of bovine incisors and divided into six groups (n=10).

Effect of light curing modes and light curing time on the microhardness of a hybrid composite resin.

Aims: The aim of this in vitro study was to evaluate the influence of light curing modes and curing time on the microhardness of a hybrid composite resin.

Methods And Materials: Forty-five Z250 composite resin specimens (3M-ESPE Dental Products, St. Paul, MN, USA) were randomly divided into nine groups (n=5): three polymerization modes (conventional-550 mW/cm2; light-emitting diodes (LED)-360 mW/cm2, and high intensity-1160 mW/cm2) and three light curing times (once, twice, and three times the manufacturer's recommendations).

Light-activation of resin cement through ceramic: relationship between irradiance intensity and bond strength to dentin.

This study investigated the relationship between the irradiance transmitted through ceramic and the bond strength of a resin cement to dentin. After application of an adhesive system, elastomer molds with cylindrical orifices (1.2 mm in diameter) were placed onto bovine dentin surfaces and filled with a photoactivated luting agent (Enforce; Dentsply Caulk).

Dentine sealing provided by smear layer/smear plugs vs. adhesive resins/resin tags.

The aim of this study was to evaluate the ability of five experimental resins, which ranged from hydrophobic to hydrophilic blends, to seal acid-etched dentine saturated with water or ethanol. The experimental resins (R1, R2, R3, R4, and R5) were evaluated as neat bonding agents (100% resin) or as solutions solvated with absolute ethanol (70% resin/30% ethanol). Fluid conductance was measured at 20 cm H(2)O hydrostatic pressure after sound dentine surfaces were: (i) covered with a smear layer; (ii) acid-etched; or (iii) bonded with neat or solvated resins, which were applied to acid-etched dentine saturated with water or ethanol.

Evaluation of an educational program for children with high risk of caries.

The goal of this study was to evaluate a 15-month educational program designed to children. The sample consisted of 60 six-year olds, randomly assigned into control and experimental group. The control consisted of tooth brushing training, once a year.

Effect of water storage and surface treatments on the tensile bond strength of IPS Empress 2 ceramic.

Purpose: The aim of this study was to evaluate the effect of water storage (24 hours and 1 year) on the tensile bond strength between the IPS Empress 2 ceramic and Variolink II resin cement under different superficial treatments.

Materials And Methods: One hundred and eighty disks with diameters of 5.3 mm at the top and 7.

In vivo preservation of the hybrid layer by chlorhexidine.

Host-derived proteases have been reported to degrade the collagen matrix of incompletely-resin-infiltrated dentin. This study tested the hypothesis that interfacial degradation of resin-dentin bonds may be prevented or delayed by the application of chlorhexidine (CHX), a matrix metalloproteinase inhibitor, to dentin after phosphoric acid-etching. Contralateral pairs of resin-bonded Class I restorations in non-carious third molars were kept under intra-oral function for 14 months.

Microtensile bond strength between crown and root dentin and two adhesive systems.

Statement Of Problem: Since bonding agent effectiveness is usually evaluated on coronal substrates, available knowledge for judging the effectiveness of bonds to root dentin is insufficient.

Purpose: The objective of this study was to evaluate the bond strength of 2 adhesive systems to crown, cervical finish line, and post space dentin.

Material And Methods: Twenty bovine maxillary incisors were used in this study.

Age-specific salivary immunoglobulin A response to Streptococcus mutans GbpB.

In a follow-up study of children infected with Streptococcus mutans at an early age (children previously shown to respond poorly to S. mutans GbpB), there was a delay in their immune response, rather than a complete inability to respond to this antigen. Epitopes in the N-terminal third of GbpB were identified as targets for naturally induced immunoglobulin A antibody in children at an early age.