This experiment was conducted in order to improve the adhesiveness of a resin composite to Er-YAG laser irradiated dentin. According to some reports if a resin was applied to a dentin surface irradiated with the Er-YAG laser using the conventional resin composite adhesion system, the resin adhesiveness decreased remarkably. The author examined experimental primers containing some concentrations of acetone instead of water, so as not to decalcify the dentin, and conducted a comparative study by changing the energy of additional laser irradiation. Er-YAG laser irradiation was applied to the surfaces of bovine teeth at an output power of 220mJ, followed by 30, 60, 90, or 150mJ, to form concavities in the dentin. The experimental primer and bonding material were then placed onto the laser irradiated dentin, and the concavities were filled with composite resin. The tensile adhesion strength was measured by universal tester. Consequently, l0wt% MDP/35wt% HEMA/55wt% Acetone primer improved adhesion of a composite resin to irradiated dentin with a 220mJ Er-YAG laser followed by additional 30 to 90mJ. Probably, the acetone solution primers were improved both monomer penetration and infiltration, that decreased thermally - modified layer with additional laser irradiation.

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Shear bond strength between two kind of prefabricated metal posts and a composite resin core material was measured. SUS304 stainless steel and Ti-6Al-4V titanium alloy were pretreated with ten different methods, followed by bonding of the composite resin core material. Thereafter, shear bond strength of all specimens was measured (TCO). In addition, 5, 000 times of thermal cycling were added in six preteating methods with comparatively higher bond strength and the bond strength was also measured in these specimens.
Shear bond strength of SUS304 stainless steel and Ti-6A1-4V titanium alloy were similar in any pretreating methods. The most recommendable methods of pretreating were sandblasting combined with either Clearfil Photo Bond or Clearfil Liner Bond II Σ primer.

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This article reviews the definition of bonding systems, their classification, and the composition of various products, with the aim of providing fundamental information that will help the reader use the adhesives in dental treatment. With respect to tooth substances, the article introduces the evolution of bonding systems from so-called the first to the sixth generation. Adhesion is also described, focusing on the relation between metal surface chemical elements and functional monomers, the activation of silane agents and their shelf life, and the difference between resin composites and PMMA resins.

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The purpose of this in vitro study was to evaluate the microleakage of flowable composite resins restored cavities which were prepared by an air-abrasion system.
Extracted human sound incisors were employed as specimens in this study, and they were divided into 6 groups in each group were used 10teeth. In Group I, cavities were prepared with carbide burs without bevel at enamel margin. In Group II, cavities were prepared with carbide burs with bevel at enamel margin. In Group M and V, cavities were prepared with the air-abrasion system, and the lmm-distance between the specimen's surface and the air abrasive nozzle was used in the preparation, and in Group N and VI, cavities were prepared by means of the air-abrasion system with the 3mm-distance. To restore the cavities of Group I-IV, they were treated with self-etching bonding system. A flowable resin was employed as a restorative resin. The cavities of Group III-VI were also restored with the flowable resin, however they were pretreated with a wet-bonding technique. The all restored specimens were load-cycled (800g/10, 000cycles), and placed into 1% Methylen-Blue solution for 24hours. Then the specimens were sectioned, and the degree of dye penetration at the incisal and the cervical cavity walls were determined.
The results showed there was no statistically significant difference between Group I-IV or III-VI, and it suggests that the marginal microleakage of cavities prepared by the airabrasion is almost the same as that by the drill when the flowable resin are used in conjunction with both the self-etching and the wet-bonding technique.

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It is claimed that Ariston AT^TM releases hydroxide ions when the intraoral pH value decreased and this effect may result in a buffering of acidity in the oral environment. This particular restorative material also releases fluoride and calcium ions. The purpose of this study was to investigate the effects of Ariston AT^TM on buffering of acids, and to investigate the mechanical property by using a bi-axial flexural strength test.
The results of this study showed that Ariston AT^TM had an ability of buffering of acids without any decline of the mechanical property. Hence, it seems that Ariston AT^TM is one of the restorative materials, which can be used not only in restorative procedures but also in caries preventions.

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The marginal adaptation of a commercial flowable resin composite (Tetric Flow, Vivadent, Lichtenstein, Hakusui Co. Ltd.) was compared to those of the conventional composites by measuring the wall-to-wall polymerization contraction gap width in the cylindrical dentin cavity. The dentin cavity wall was pretreated with a commercial (Syntac SC, Vivadent, Lichtenstein Hakusui Co. Ltd.) or an experimental dentin bonding system. The marginal integrity was affected by the dentin bonding systems tested regardless of the kind of the resin composite. The gap formation was prevented completely when the flowable resin composite was filled in the cavity mediated with the experimental dentin bonding system composed of EDTA conditioning, glyceryl monomethacylate priming and Clearfil Photo Bond application. The poor marginal adaptation of a conventional composite tested was considered to be due to its high filler content resulting in the prevention of the flow of composite into the cavity during polymerization.

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