The aim of this study was to examine the filled structure of 11 kinds of flowable resin composites in SEM by means of the Ar-ion beam etcing, and to evaluate the flow-ability of composite pastes.
It was revealed that the Palfique Estelite LV comprised 2 kinds of submicron spherical filler particle of 0.08 and 0.4μm in diameter, the organic complex filler particles were loaded in Revolution, and other flowable composites consisted of conventional small filler particle ranging from 1 to 5μm in diameter.
Some of elements such as Si, Al, Ba, Zr, Ti, Sr, and/or Yb, were detected in flowable composites. F was detected in the Beautifil Flow and UniFil Flow composites, which showed possibility of fluoride release.
These three composites, such as Beautifil Flow (High flow), Palfique Estelite LV (High flow), UniFil Flow showed relatively higher flow-ability than others.

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The aim of this study was to observe the topographical changes of the seven kinds of set bonding resin surfaces after the argon ion beam etching, examining the hardness of the set bonding resin surfaces. Each kind of the bonding resins was light cured sufficiently in the accessory dish, embedded in an epoxy resin, and polished. Nano-hardness of the resin surfaces were measured with the nano-indentation tester. Then, the polished surfaces of each of the set bonding resins were observed under the FE-SEM. After subjected to the argon ion beam etching, the surfaces were observed again and compared with the polished surface image. The hardness value of the bonding resins containing filler particles were higher than those without filler particles, and the resin surfaces of the two-step type systems were harder than the one-step type resins. The argon ion beam etching induced identical topographical changes for the individual bonding resin. It was considered that these changes were related to the filler loadings and the kinds or compositions of the monomer employed in the bonding resins, but not correlated with the hardness of the surface.

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RZ-II material (Sun Medical) is a recently developed single step one bottle self-etching system that produces a “bacteriometic” hybridized interface and leaves a complete surface coating layer with one application. The purpose of this study was to examine the mechanical properties of RZ-II cohesive agent when compared to other commercial systems. Twenty dentin discs were prepared from freshly extracted human third molars, the surfaces were treated with the following systems. Each of four systems, a self-etching system (MEGA BOND), two dentin coating materials (SB coat) with self-etching system (AQBond), and a low viscosity resin (Protect liner-F) with MEGA BOND was applied to dentin surface respectively as per the manufacturers' directions. RZ-II was applied by a single and with double coats to the prepared dentin surface with the following manufacturer's directions. FE-SEM observations and nanohardness measurements of these coating surfaces were performed after 1 hour and 1 week in water storage. The surface coating of RZ-II by double coats showed a smoother surface than that with single coat. The nanohardness of RZ-II was statistically higher than the other tested materials. Our data demonstrate that the newly developed dentin coating material, RZ-II is useful for treatment of instrumented dentin as an indirect restoration in clinical situations

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In this study, the effectiveness of (one-step type) self-etching bonding agent and flowable resin composite on the adhesion of orthodontic metal bracket to enamel was investigated.
As commercially available self-etching bonding agent and flowable resin composite, AQ Bond and Metafil Flo were used. Orthodontic metal bracket was bonded to ground bovine enamel. The shear bond strengths were measured after 1 day immersion in 37°C water. The mean bond strength was 8.6MPa. After thermo cycling for 60 cycles, the mean bondstrength was 5.6MPa. The results suggested that this adhesive system could be applicable to orthodontic treatment.

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