Kohyoh Soeno

Surface treatment with ascorbic acid and ferric chloride improves the micro-tensile bond strength of 4-META/MMA-TBB resin to dentin.

OBJECTIVE The purpose of this study was to investigate the efficacy of an experimental dentin conditioner consisting of ascorbic acid (AA) and ferric chloride (Fe), in terms of micro-tensile bond strength (microTBS). METHODS Five experimental solutions were prepared and evaluated: 10% AA and 5% Fe (10AA-5Fe); 10% AA and 0% Fe (10AA-0Fe); 0% AA and 5% Fe (0AA-5Fe); 10% citric acid and 3% ferric chloride (10-3); and, 0% AA and 0% Fe (0AA-0Fe). Flattened dentin surfaces were treated with each of the experimental solutions. A composite material rod was bonded to the dentin surface with a self curing luting agent (4-META/MMA-TBB resin). The specimens were stressed to failure under tension after 24h of immersion in water. RESULTS The 10AA-5Fe group showed significantly higher bond strength than the 10AA-0Fe, 0AA-5Fe, 10-3 and AA-0Fe groups. CONCLUSION It was found that an experimental conditioner consisting of 10% ascorbic acid and 5% ferric chloride significantly improved the micro-tensile bond strength between 4-META/MMA-TBB resin and dentin.

Comparison of four silane primers and an isocyanate primer for bonding of tri-n-butylborane resin to a leucite-reinforced glass ceramic

PURPOSE The purpose of the present study was to compare the effectiveness of an isocyanate monomer and four different silane monomers as primer components for bonding a leucite-reinforced glass ceramic (GN-Ceram Block). METHODS Four different methyl-methacrylate based primers, each with three different concentrations (1, 4, or 16wt%) of 2-methacryloxyethylisocyanate (MOI), 3-methacryloxypropylmethyldimethoxysilane (MDS), 3-methacryloxypropyltrimethoxysilane (MTS), and 3-acryloxypropyltrimethoxysilane (ATS) were prepared. A commercially available silane primer (ESPE™Sil) was also used as a control. The GN-Ceram Block specimen was ground with silicon carbide paper, rinsed, primed, and then bonded to a resin composite disk using a tri-n-butylborane-initiated self-curing luting agent. After 24-h immersion in water, the shear bond strengths were determined. RESULTS The highest level of bond strength was obtained with 4wt% MTS (45.2 MPa) and 4wt% ATS (38.7 MPa), followed by 4wt% MOI (29.8 MPa), ESPE™Sil (28.1 MPa), and 4wt% MDS (27.9 MPa). For each MTS, ATS, MOI, and MDS, the bond strengths for concentrations of 4wt% and 16wt% were not significantly different. No significant differences were found between 4wt% ATS, 4wt% MOI, ESPE™Sil, and 4wt% MDS. The use of any of these primers led to a significant increase in bond strength compared to an unprimed control (13.8 MPa). CONCLUSIONS The type and concentration of monomers dissolved in the primer influence the bond strength between a tri-n-butylborane resin and a leucite-reinforced glass ceramic GN-Ceram Block. The effectiveness of MOI was found to be comparable to that of MDS, ATS, and ESPE™Sil, but inferior to that of MTS.

The effect of a peroxidase primer on bond strength of three luting systems to dentin

The purpose of the present study was to investigate the effect of an experimental primer containing a microperoxidase (MP-11) with 2-hydroxyethyl methacrylate on adhesive bonding of three different luting systems and dentin. The luting systems prepared were three etch-and-rinse systems (10-3/Super-Bond, 10-0/Super-Bond, 65PA/Super-Bond), a self-etching system (PanaviaF2.0), and a self-adhesive system (SA-Luting). These luting systems were used in conjunction with the MP-11 primer, and were designated as 10-3/MP-11/Super-Bond, 10-0/MP-11/Super-Bond, 65PA/MP-11/Super-Bond, MP-11/PanaviaF2.0, MP-11/SA-Luting, respectively. The dentin surfaces of human premolar teeth were treated, and then bonded with acrylic rods. Shear bond strengths were determined after 24 h of storage in water. The maximum mean bond strength was obtained with 10-0/MP-11/Super-Bond (48.7 +/- 6.6 MPa), followed by 10-3/MP-11/Super-Bond (36.3 +/- 10.2 MPa), 65PA/MP-11/Super-Bond (32.9 +/- 9.2 MPa), 10-3/Super-Bond (26.6 +/- 6.7 MPa), MP-11/PanaviaF2.0 (21.4 +/- 5.6 MPa), MP-11/SA-Luting (17.2 +/- 3.5 MPa), PanaviaF2.0 (16.9 +/- 5.7 MPa), 65PA/Super-Bond (12.8 +/- 2.0 MPa), SA-Luting (11.2 +/- 5.4 MPa), and 10-0/Super-Bond (9.6 +/- 3.9 MPa). The additional use of MP-11 primer significantly improved the bond strengths in the etch-and-rinse systems with 4-META/MMA-TBB resin. It is suggested that the peroxidase has a potential to improve dentin adhesion in the etch-and rinse, self-etching, and self-adhesive systems.

A cast metal core for a deformed implant body: case report.

The present report consists of a clinical evaluation of an osseointegrated implant using a cast metal core instead of abutment for a deformed implant body. The intramobile connector insert for the implant in the mandibular left first premolar region broke 7 years after the superstructure was attached to the implant system. The intramobile connector insert was replaced, and the prosthesis was reattached, but the new intramobile connector insert broke again 2 weeks later. A thorough examination confirmed deformation of the upper section of the implant body in the mandibular left first molar region. Breakage of the new intramobile connector insert in the mandibular left first premolar region was believed to be due to deformation of the implant body in the mandibular left first molar region. Therefore, a cast metal core was used to deal with the deformation of the implant body in this region. Although slight bone resorption was observed around the implant body after 5 years, no major problems were found in the implant body itself.