The present study investigates the influence of a pulpotomy agent formocresol on bond strength between dentin and Super-Bond C&B (Sun Medical).
In addition to the commercially available formocresol, four experimental drugs, i. e. Ethanol, Formaline/Ethanol, Cresol/Ethanol, and Formaline/Cresol/Ethanol, were prepared. The dentin surfaces of bovine teeth exposed by grinding, soaked in the respective drugs, and then bonded with acrylic rods using Super-Bond C&B; tensile bond strengths were determined after one-day immersion in water. Data were analyzed by ANOVA and Duncan's new multiple range test.
The bond strengths were influenced by the type of drug, soaking period, and their combinations. The mean bond strengths varied from 4.2 to 17.9 MPa. All drugs decreased the bond strength values. The lowest level of bond strengths (4.2to6.4 MPa) were detected for the groups without formaline.
These findings suggest that formaldehyde helps reduce the undesirable effects of ethanol and cresol in this Super-Bond C&B dentin bonding system.

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The recent adhesive restorative materials enable us to restore decayed teeth without reducing sound tooth structure. Caries disclosing dye solution (Caries Detector) is the most reliable method to disclose infected carious dentin. However, Caries Detector requires repeated staining and mechanical removal of carious dentin, since the penetration of the dye solution into infected tissue is limited. It requires long chair time to remove the infected carious dentin tissue by using Caries Detector and cutting rotary instruments.
The purpose of this study was to evaluate selective caries removal using an air-abrasive technique, changing abrasive powders and air pressures. Selective removal of carious dentin was performed without reducing intact dentin by using particles with smaller hardness than the hardness of intact dentin.

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The interface between the experimental glass-ionomer cements and dentin was observed by SEM. In the case of photo-cured glass-ionomer cement, the zone with 3μm thickness was observed after HCl immersion. But the thickness of this zone decreased to 0.5μm after NaOCl immersion. The demineralized dentin, where the penetration of monomers was insufficient, was not dissolved by HCl immersion, but was dissolved by NaOCl immersion. The zone in the specimen after NaOCl immersion was the hybrid dentin layer, which was formed by the penetration and polymerization of HEMA. In the case of conventional glass-ionomer cement, the zone which was observed after HCl immersion was completely diminished by NaOCl immersion. The hybrid dentin layer was not formed by the application of conventional glass-ionomer cement.

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The restoration of minimum tooth reduction could be effected by the progress of adhesive dentistry. It has certainly prolonged the life span of the tooth, and produced many advantages to the patient. However, it is not one and only factor to decide the most suitable restoration for patients. All factors were provided and divided into two groups, direct factors on restorative methods/materials and indirect factors on patients/tooth substances. Absolute ratings for restoration were provided from direct factors, and relative ratings were decided after consideration of indirect factors. A restoration obtained the highest relative rating was finally selected in clinics. Decision-makings for restorations were considerably depended of the age, sex, social position, and needs of patients. It is concluded that the most suitable restoration should be decided after general consideration.

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In conventional prosthodontic treatment, large quantity of tooth reduction is necessary to achieve sufficient retention and esthetics for fixed prostheses and even removal of dental pulp is accepted. However, last research on prognoses of dental restoration revealed that the conservation of tooth substrate, especially enamel is considered to be essential for the elongation of life piriods of restored teeth. In the prosthodontic treatment with intact teeth, application of adhesion-fixed prostheses which could minimize amount of loss of tissues is desirable.
In this article, the clinical evaluation of the treatment applied adhesion or adhesion-mechanically retained bridge which is the effective method for conservation of tooth substrate in the case of fixed partial denture with intact abutment teeth was described. Furthermore, the practice and problems of adhesion pontic bridge, new fixed prosthodontic appliance which does not require removal of enamel so much were described.

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Bond strength to a representative silver-palladium-copper-gold alloy (Castwell M. C. 12) was evaluated in vitro using two metal conditioners and two luting agents. One primer (Metaltite) contained 6-methacryloyloxyhexyl 2-thiouracil-5-carboxylate (MTU-6) in ethanol. The other primer (V-Primer) contained 6-(4-vinylbenzyl-n-propyl) amino-1, 3, 5-triazine-2, 4-dithione (VTD) in acetone. The luting agents assessed were a two-paste dual-activated composite (Bistite II) and a tri-n-butylborane-initiated methyl methacrylate-based adhesive resin (Super-Bond opaque). The metal specimens were bonded with six combinations of two primers and two luting agents including unprimed two controls. Shear bond strengths were determined before and after thermocycling. Both primers significantly elevated the post-thermocycling bond strengths of the luting agents joined to the alloy. Of the two primers assessed, the Metaltite material exhibited greater bond strength than the V-Primer agent regardless type of luting agent.
For unprimed groups, the Super-Bond resin showed reduction in bond strength by application of thermal stress, whereas the Bistite luting agent demonstrated greater standard deviations.

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This study compared the in vitro performance and the failure characteristics of the prefabricated bovine dentin post, bovine dentin core combinations with steel prefabricated post, bovine dentin core combinations. Using grinding bovine tooth in diameter 6mm, length 12mm by engine lathe with bovine dentin post in diameter 2mm, leagth 20mm, and same tooth with steel prefabricated post, bovine dentin core were then tested to failure with an obliquely applied compressive load at 60 degrees in a testing machine.
The mean stress values at failure (kgf) with standard deviations for specimens restored with dentine post is 224 (38. 9), specimens restored with steel post 228. 8 (48. 7). The teeth restored with dentine post has no fractures were observed. One to two cracks, fractures were observed at the teeth restored with steel post. This result suggest that bovine dentine post that has same elastic modulus of root makes the stress distribution uniformly to root.

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The adhesive dentistry has made remarkable progress in recent years, resulting in reliable adhesion of composite resin to dentin. In addition, many research and new operative methods based on the adhesive dentistry has been reported in the field of coronal radicular stabilization, including the adhesive amalgam core buildup, direct-indirect method with light curing composite resin and indirect method with dual curing composite resin.
The present study discusses composite resin as core materials regarding physical properties, adhesive strength to dentin, retentive forces with prefabricated metal posts and failure strength.

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