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.The definitive version is available at www.blackwell-synergy.co

Effects of three silane primers and five adhesive agents on the bond strength of composite material for a computer-aided design and manufacturing system

Objective: The objective of this study was to evaluate the effects of combinations of silane primers and adhesive agents on the bond strength of a composite block for a computer-aided design and manufacturing system. Material and Methods: Three silane primers [Clearfil Ceramic Primer (CP), Super-Bond PZ Primer (PZ), and GC Ceramic Primer II (GP)] were used in conjunction with five adhesive agents [G-Premio Bond (P-Bond), Repair Adhe Adhesive (R-Adhesive), Super-Bond D-Liner Dual (SB-Dual), Super-Bond C&B (SB-Self), and SB-Dual without tributylborane derivative (SB-Light)]. The surface of a composite block (Gradia Block) was ground with silicon carbide paper. After treatment with a silane primer, a adhesive agent was applied to each testing specimen. The specimens were then bonded with a light-curing resin composite. After 24 h, the shear bond strength values were determined and compared using a post hoc test (α=0.05, n=8/group). We also prepared control specimens without primer (No primer) and/or without adhesive agent (No adhesive). Results:PZ/SB-Dual and GP/SB-Dual presented the highest bond strength, followed by GP/P-Bond, CP/SB-Dual, CP/R-Adhesive, No primer/SB-Dual, GP/R-Adhesive, CP/P-Bond, No primer/R-Adhesive, PZ/R-Adhesive, CP/SB-Self, PZ/P-Bond, PZ/SB-Self, and GP/SB-Self in descending order of bond strength. No primer/P-Bond, No primer/SB-Self, and all specimens in the SB-Light and No adhesive groups presented the lowest bond strengths. Conclusion: A dual-curing adhesive agent (SB-Dual) containing a tributylborane derivative in combination with a silane primer (GP or PZ) presents a greater bond strength between the composite block and the repairing resin composite than the comparators used in the study

Effects of Primers Containing Thiouracil and Phosphate Monomers on Bonding of Resin to Ag-Pd-Au Alloy

The purpose of the present study was to evaluate the effects of four experilnental prinlers on bond strength between a self-curing luting agent and silver-palladiuln-gold alloy. The experinlental primers were in lnixed solutions of a thiouracil primer (Metaltite) and a phosphate primer (Epricord, PM, PE, or PP), which were designated as Metaltite/Epricord,Metaltite/PM, Metaltite/PE, and Metaltite/PP respectively. Three prilners (Metal Primer II, V-Primer, and Alloy Primer) were also prepared as controls. Allunina-blasted metal alloys \u27were bonded with acrylic rods. After 5,000 thermocycles, the maximu111 shear bond strength was obtained with Metaltite/PE (27.8±2.4 MPa) and Metaltite/Epricord (27.6± 5.9 MPa), followed by Metaltite/PP, Alloy Prilner, Metaltite, Metaltite/PM, Metal Primer II, V-Primer, and Epricord. PE, PM, and PP showed the lowest bond strength. Results of this study revealed that the cOlnbined use of a thiouracil Inonomer and a phosphate lnonomer ilnproved adhesive bonding. In this light, clinicians should pay attention to the types of functional monomers dissolved in a primer when fabricating resin-bonded prostheses

Flexural strength of the joint between glass-infiltrated alumina frames and the alumina-magnesia modifier.

PURPOSE: The purpose of the present study was to evaluate the flexural strength of the joint between glass-infiltrated alumina frames and the experimental adjusting agent (MA modifier) that contains alumina and magnesia. METHODS: A commercially available adjusting agent (Optimizer), a slurry of alumina powder (Alumina modifier), and a bulk specimen (joint-free alumina) were used as controls. Beam-shaped alumina specimens were machined from an alumina block. The ends of two alumina beams were positioned at an interval of 1.0mm and joined with each adjusting agent. The joined specimens were subjected to sintering, glass infiltration firing, glass control firing, and then a three-point bending test was carried out to evaluate the flexural strength. RESULTS: The maximum flexural strength was observed in the joint-free alumina, followed by MA modifier, Optimizer and Alumina modifier. With the exception for joint-free alumina, the failure modes after three-point bending test tended to shift from adhesive failure at substrate material-adjusting agent interface to cohesive failure within adjusting agent as the flexural strength increased. CONCLUSIONS: The use of MA modifier significantly improved the flexural strength of joined glass-infiltrated alumina frame. The MA modifier could be applied for adjusting the margin as an alternative to Optimizer when fabricating crown and bridge substructures with In-Ceram Alumina system

The effect of magnesium oxide supplementation to aluminum oxide slip on the jointing of aluminum oxide bars

The purpose of this study was to investigate the effect of modifying aluminum oxide slips with magnesium oxide (MgO) tocreate a jointing material for In-CeramR Alumina. Jointed In-CeramR Alumina bars with In-CeramR Alumina slips containing0－1.0 mass％ MgO were examined by a three-point bending test. Joint-free bars were also tested as controls.Fracture surfaces were evaluated by scanning electron microscopy. In addition, linear shrinkage and fracture toughnesswere assessed.　　The 0.3 mass％ MgO group showed the highest flexural strength among the jointed groups, and there were no statisticaldifferences between the joint-free control groups. The fracture surface of 0.3 mass％ MgO group showed increasedsintering densification with reduced micropore size. No linear shrinkage was observed with the addition of MgO to thealumina slip. Added MgO was also effective in boosting fracture toughness. The present findings indicate that the MgOsupplementedbinding material is useful for clinical applications

A novel insertion pathway of mitochondrial outer membrane proteins with multiple transmembrane segments

The central channel Tom40 of the preprotein translocase of outer membrane (TOM) complex is thought to be responsible for the import of virtually all preproteins synthesized outside the mitochondria. In this study, we analyze the topogenesis of the peripheral benzodiazepine receptor (PBR), which integrates into the mitochondrial outer membrane (MOM) through five hydrophobic transmembrane segments (TMSs) and functions in cholesterol import into the inner membrane. Analyses of in vitro and in vivo import into TOM component–depleted mitochondria reveal that PBR import (1) depends on the import receptor Tom70 but requires neither the Tom20 and Tom22 import receptors nor the import channel Tom40, (2) shares the post-Tom70 pathway with the C-tail–anchored proteins, and (3) requires factors of the mitochondrial intermembrane space. Furthermore, membrane integration of mitofusins and mitochondrial ubiquitin ligase, the MOM proteins with two and four TMSs, respectively, proceeds through the same initial pathway. These findings reveal a previously unidentified pathway of the membrane integration of MOM proteins with multiple TMSs

Review of methyl methacrylate (MMA)/tributylborane (TBB)-initiated resin adhesive to dentin

This review, focusing mainly on research related to methyl methacrylate/tributylborane (MMA/TBB) resin, presents the early history of dentin bonding and MMA/TBB adhesive resin, followed by characteristics of resin bonding to dentin. Bond strengths of MMA/TBB adhesive resin to different adherends were discussed and compared with other bonding systems. Factors affecting bond strength (such as conditioners, primers, and medicaments used for dental treatment), bonding mechanism, and polymerization characteristics of MMA/TBB resin were also discussed. This review further reveals the unique adhesion features between MMA/TBB resin and dentin: in addition to monomer diffusion into the demineralized dentin surface, graft polymerization of MMA onto dentin collagen and interfacial initiation of polymerization at the resin-dentin interface provide the key bonding mechanisms

Effects of two methyl methacrylate-tributylborane-based luting agents with a silane-phosphate primer on bonding of four different CAD/CAM resin composite materials

Purpose: This study compared the bond strengths of four adhesive systems and four different resin composite block materials: Gradia Block (GR), Shofu Block HC (SH), Estelite Block (ES), and KZR-CAD HR2 (KZ).Methods: A primer (PZ-AB) containing a silane (γ-MPTS) with 10-methacryloyloxydecyl dihydrogen phosphate (MDP) was applied to ground surfaces of the resin composite block specimens, and the specimens were then bonded to stainless-steel rods using two methyl methacrylatetributylborane (MMA-TBB)-based luting agents (SB and MT), designated as the PZ-AB/SB and PZ-AB/MT adhesive systems, respectively. The SB resin contained 4-methacryloyloxyethyl trimellitate anhydride (4-META), whereas the MT resin did not. The SB resin without primer (No primer/ SB) and a dual-curing composite-type adhesive system (UPA/RelyX) were used as controls. The 24-h tensile bond strengths were determined and analyzed using the Tukey-Kramer HSD test (α = 0.05, n = 8).Results: The highest bond strengths were obtained for the GR/PZ-AB/MT, GR/PZ-AB/SB, KZ/PZ-AB/MT, ES/PZ-AB/SB, and KZ/No primer/SB groups, whereas the KZ/UPA/RelyX, ES/UPA/RelyX, SH/UPA/RelyX, and SH/No primer/SB groups exhibited the lowest bond strengths.Conclusion: For each resin composite block material primed with γ-MPTS and MDP, the MMA-TBB-based luting agents, irrespective of the presence of 4-META, provided higher bond strengths than the dual-curing composite-type adhesive system