Composite repair: On the fatigue strength of universal adhesives.

Objectives: To determine whether the composition of universal adhesives and the use of silane coupling agents could affect the fatigue strength of composite repair.

Methods: Composite samples were aged in water at 37 °C for 90 days and bonded to fresh composite to produce twin-bonded bar-shaped composite specimens (2 × 2 × 12 mm). Five universal adhesives, a multistep composite repair system and a hydrophobic solvent-free resin associated to a separate silane coupling agent application were used for bonding.

Long-term effect of curcuminoid treatment on resin-to-dentin bond strength.

Endogenous dentin proteases contribute to the degradation of collagen fibrils in the hybrid layer. Recently, inhibition of host-derived proteases by curcuminoids has shown promising results. The aim of this study was to evaluate the effect of curcuminoid treatment on the microtensile bond strength (μTBS) after 24 h or 12 months of storage.

The pursuit of resin-dentin bond durability: Simultaneous enhancement of collagen structure and polymer network formation in hybrid layers.

Objective: Imperfect polymer formation as well as collagen's susceptibility to enzymatic degradation increase the vulnerability of hybrid layers over time. This study investigated the effect of new dimethyl sulfoxide (DMSO)-containing pretreatments on long-term bond strength, hybrid layer quality, monomer conversion and collagen structure.

Methods: HPO-etched mid-coronal dentin surfaces from extracted human molars (n = 8) were randomly treated with aqueous and ethanolic DMSO solutions or following the ethanol-wet bonding technique.

Effect of gallic acid addition on some mechanical properties of self-adhesive resin cements.

Self-adhesive resin cements (RCs) activate matrix metalloproteinase (MMP) and cathepsin-related collagen degradation, and gallic acid (GA) inhibits the activity of both MMPs and cysteine cathepsins. The purpose of this study was to evaluate the setting time, biaxial flexural strength, and Vickers hardness of self-adhesive RCs after the addition of two different concentrations of GA. RelyX U200 (3M ESPE) and Panavia SA (Kuraray) were modified with 0.

Selective dentin etching: A potential method to improve bonding effectiveness of universal adhesives.

Objectives: To evaluate whether selective dentin etching protocols using reduced phosphoric acid (HPO) etching-times would affect the resin-dentin interaction of a universal adhesive to improve long-term bonding effectiveness.

Methods: Mid-coronal flat dentin surfaces were produced on sound third molars, selectively etched with 32% HPO for 3, 5, 10 or 15 s and bonded with a universal adhesive (Scotchbond Universal, 3 M ESPE: SU). SU in self-etch mode and a three-step etch-and-rinse adhesive were used as control groups.

Durability of adhesive bonds to tooth structure involving the DEJ.

The importance of the Dentin Enamel Junction (DEJ) to the durability of adhesive bonds to tooth structure is unclear. In fact, no investigation has been reported on contributions of the DEJ to the fatigue resistance of the bonded interface. In this study, the durability of adhesive bonds to tooth structure involving the DEJ was quantified and compared to that of adhesive bonds to enamel only, not including the DEJ.

Is the inactivation of dentin proteases by crosslinkers reversible?

Objective: Inactivation of dentin proteases by crosslinkers has been suggested as a way to prevent the degradation of dentin collagen in the hybrid layer. However, it is not known if the inhibition is reversible. The aim of this study was to evaluate the inactivation effect of various crosslinkers on dentin protease activity over a period of 6 months.

Influence of dimethyl sulfoxide used as a solvent on the physical properties and long-term dentin bonding of hydrophilic resins.

Objective: To examine the feasibility of dimethyl sulfoxide (DMSO) incorporation into relatively hydrophilic resins as a new potential method to improve the durability of resin-dentin bonds.

Methods: Six experimental light-curing BisGMA/HEMA resins solvated in ethanol and DMSO with increasing concentrations of DMSO (0, 0.5, 1, 2, 4 and 10wt%) were prepared.

Fatigue of the resin-enamel bonded interface and the mechanisms of failure.

The durability of adhesive bonds to enamel and dentin and the mechanisms of degradation caused by cyclic loading are important to the survival of composite restorations. In this study a novel method of evaluation was used to determine the strength of resin-enamel bonded interfaces under oth static and cyclic loading, and to identify the mechanisms of failure. Specimens with twin interfaces of enamel bonded to commercial resin composite were loaded in monotonic and cyclic 4-point flexure to failure within a hydrated environment.

Fatigue of the resin-dentin interface: a new approach for evaluating the durability of dentin bonds.

Unlabelled: There are concerns regarding the longevity of resin composite restorations and the clinical relevance of in vitro bond strength testing to the durability of dentin bonds in vivo.

Objective: The objectives of this investigation were to: (1) develop a new method of experimental evaluation for quantifying the durability of dentin bonds, (2) apply this method to characterize the interfacial strength of a selected commercial system under both monotonic and cyclic loading, and (3) distinguish mechanisms contributing to the interface degradation and failure.

Methods: A new method for fatigue testing the resin-dentin interface was developed based on a four-point flexure arrangement that includes two identical bonded interfaces.

On the fatigue behavior of resin-dentin bonds after degradation by biofilm.

The durability of resin-dentin bonds is a growing concern in the placement of composite restorations. Most reported evaluations concerning the mechanical behavior of the bonded interface are conducted using static loading to failure only. They also do not account for the acid production of biofilms, which is one of the most common contributors to interfacial failures in vivo.

Experiments on in vivo biofilm formation and in vitro adhesion of Candida species on polysiloxane liners.

Objectives: Microorganisms may colonise polysiloxane soft liners leading to bio-deterioration. The aim of this study was to investigate in vitro adhesion and in vivo biofilm formation of Candida species on polysiloxane surfaces.

Methods: The materials used in this study were Molloplast B, GC Reline soft, Mollosil Plus, Silagum Comfort and Palapress Vario.

A prospective study on the clinical performance of polysiloxane soft liners: one-year results.

Objective: The aim of the present study was to evaluate the clinical performance of four denture soft liners up to 12 months.

Materials And Methods: Thirty-three edentulous patients who experienced difficulties when using hard denture bases because of changes in denture-supporting tissues were accepted for the study and randomly received Molloplast B, GC Reline Soft, Silagum Comfort, or Mollosil Plus relines. Performance of the materials was evaluated using nine criteria at 3, 6, and 12 months: physical integrity, surface detail, adhesion, color, odor, plaque accumulation, resilience, hygiene, and mucosal condition.

Effect of thermocycling on tensile strength and tear resistance of four soft denture liners.

This study evaluated the effect of thermocycling on the tensile strength and tear resistance of four long-term soft denture liners. One light-activated (Astron Light, AL), two chemically activated (GC Reline Soft, GC; Silagum Comfort, SC), and one heat-cured (Molloplast-B, MLP) soft liner materials were tested. Dumbbell and trouser-leg specimen geometries were used for tensile strength and tear resistance tests, respectively.

Color change evaluation of denture soft lining materials in coffee and tea.

This study evaluated the color stability of soft denture liners after being exposed to coffee and tea solutions for different time periods. Four soft denture liners and a denture base polymer were tested. Five specimens of each material were immersed in either coffee or tea solution at 50 +/- 1 degrees C for one, three, nine, 24, 48, and 96 hours.

Evaluation of bond strength of soft relining materials to denture base polymers.

Objectives: To evaluate the initial bonding properties of recently and previously introduced soft relining materials to denture base polymers with different polymerization techniques and different water content.

Methods: The initial tensile bond strength of 10 soft liners (Mollosil Plus, Dentusil, Ufi gel Soft, GC Reline Soft, Silagum Comfort, Vertex Soft, Astron Soft, Molloplast B, Flexacryl Soft, Triad Resiline) to three denture base polymers (Paladon 65, Palapress Vario, Ivocap Plus) were assessed with a modified method. Paladon 65 specimens immersed in water for 3 months were also used to test the effect of water content of denture base polymer on bond strength results.

Evaluation of adhesion of chairside hard relining materials to denture base polymers.

Statement Of Problem: Removable denture bases are made of modified poly(methyl methacrylate) (PMMA), which has reliable bond strength with resins containing methyl methacrylate (MMA). However, some hard relining materials with different chemical compositions have been reported to have less than adequate bond strength to PMMA denture base polymers.

Purpose: This in vitro study evaluated the initial bonding properties of chairside hard relining materials to different removable denture base polymers, as well as the structure of the interface.