Bonding fixed prosthodontic composite resin and precious metal alloys with the use of a vinyl-thiol primer and an adhesive opaque resin.

Adhesive bonding of a light-cured fixed prosthodontic composite resin joined to silver- and gold-based alloys was investigated with the use of a metal primer and an adhesive opaque resin. The primer contained an adhesive bonding promoter for precious alloys, 6- (4-vinylbenzyl-n-propyl) amino-1, 3, 5-triazine-2, 4-dithiol (VBATDT). The cast metal specimens were alumina-blasted and primed with VBATDT acetone solution. A self-curable 4-META/MMA-TBB opaque resin was used to bond the primed metals and a light-cured composite resin. Prepared specimens were thermocycled in water and bond strengths were determined. The shear bond strengths after 100,000 thermocycles (4 degrees C to 60 degrees C for 1 minute) were 28.4 MPa for Ag-Pd-Cu-Au alloy and 20.8 MPa for type III gold alloy. This simple method may be used to bond silver or gold alloy and light-activated fixed prosthodontic composite resin.     

A new porcelain repair system with a silane coupler, ferric chloride, and adhesive opaque resin

A new porcelain repair system was developed which uses a two-liquid primer, self-cured opaque resin, and light-cured composite. The primer consisted of two liquids. One component was 4% 3-trimethoxysilylpropyl methacrylate in methyl methacrylate, and the other component was 0.5% ferric chloride in ethanol. A self-curing opaque resin, 4-META/MMA-TBB opaque resin, was used as an adhesive to bind the porcelain and the composite. Adhesive opaque resin was applied on the roughened and primed porcelain. Light-cured composite was placed over the 4-META opaque layer. A shear test was performed for investigation of the strength and durability of the bonding. The result was that for all specimens after 20,000 thermocycles, fracture or crack propagation during the shear test occurred in the porcelain, rather than in the bond. This system may be used to repair fractured porcelain facings without removal of prostheses.     

Adhesive bonding of titanium with a methacrylate–phosphate primer and self-curing adhesive resins

SUMMARY The adhesive bonding of titanium was evaluated with the use of a metal primer and three types of self curing luting agent. The primer contained 10-methacryloyloxydecyl dihydrogen phosphate (MDP). One luting agent was a composite material that contained the MDP monomer in its liquid part. The other luting agent was based on methyl methacrylate (MMA), initiated with tri-n-butylborane derivative (TBB), and contained 4-methacryloyloxyethyl trimellitate anhydride (4-META). The MMA-TBB resin without 4-META was used for the control. Pure titanium metal specimens were bonded with various combinations. Shear bond strengths were determined after repeated thermocycles in water. Both MDP and 4-META were effective in bonding titanium. The decrease in bond strength was minimum when the titanium was primed with MDP and then bonded with the TBB-initiated resins.     

Surface preparations for metal frameworks of composite resin veneered prostheses made with an adhesive opaque resin

Bond strengths of a laboratory developed light-cured composite resin to dental casting alloys were evaluated with a new adhesive opaque resin. The metal specimens were type III gold, nickel-chromium, and cobalt-chromium alloys, while the surface treatments for bonding were heating, Sn plating, and ion coating. The cast metal specimens were "particle blasted" with aluminum oxide and were surface treated. Adhesive 4-META/MMA-TBB opaque resin was applied and a light-cured composite resin was placed over the opaque layer. The prepared specimens were thermocycled in water and shear bond strengths were recorded. The light-cured composite resin was bonded strongly to heated or Sn-plated type III alloy with 4-META/MMA-TBB opaque resin. Copper ion coating in a sputter coater was effective for all three alloys, with only slightly diminished bond strengths. These methods were satisfactory for making composite resin veneered prostheses.     

Bonding durability between orthodontic brackets and human enamel treated with megabond self-etching primer using 4-META/MMA-TBB resin cement

The purpose of this study was to determine the bonding durability when a Megabond self-etching primer is used with 4-META/MMA-TBB resin to bond metal orthodontic brackets to human premolar enamel. Three conditions of enamel were prepared: Megabond self-etching primer without saliva contamination, Megabond self-etching primer with saliva contamination, and repeat Megabond self-etching priming after saliva contamination. Shear bond strengths were measured after immersion in water at 37 degrees C for 24 hours, or after 2000 or 5000 cycles of thermal cycling between 5 degrees C and 55 degrees C. There were no significant differences in shear bond strength among the three groups not only before thermal cycling, but also after thermal cycling. FE-SEM observation revealed the presence of saliva and reduced amount of resin tag formation after saliva contamination. The present study provided the evidence in human teeth that when using 4-META/MMA-TBB resin, Megabond self-etching primer treatment produced tight bonding even when surface was contaminated with saliva.     

Bonding of a mica-based castable ceramic material with a tri-n-butylborane-initiated adhesive resin

SUMMARY Adhesive bonding of a mica-based castable ceramic material (Olympus Castable Ceramics, OCC) was evaluated in vitro with the use of a silane primer in conjunction with an adhesive luting material. The primer contained a silane coupler and 4-methacryloxyethyl trimellitate anhydride (4-META), while the methyl methacrylate (MMA)-based luting agent was initiated with a tri-n-butylborane derivative (TBB) and contained 4-META (4-META/MMA-TBB resin). Ceramic specimens were sanded with No. 600 silicon carbide paper followed by blasting with alumina and/or etching with ammonium bifluoride. The specimens were bonded with various combinations and shear bond strengths were determined. Both priming and alumina blasting enhanced the bond between 4-META resin and OCC. Although etching with ammonium bifluoride roughened the ceramic surface, this procedure did not improve the bond strength. Electron probe microanalysis of the ceramic surface revealed a decrease in silicon and aluminium elements after etching with ammonium bifluoride.     

Bonding and debonding characteristics of orthodontic brackets to human enamel using modified 4-META/MMA-TBB resin

The purpose of this study was to evaluate the performance of modified 4-META/MMA-TBB resin for debonding orthodontic brackets to enamel in terms of easy and safe debonding without loss of adequate bracket bond strength. A mixture of α-tricalcium phosphate (α-TCP) and calcium fluoride (CaF₂) (1:1, w/w) was added to the polymer powder of 4-META/MMA-TBB resin. Human enamel was etched with phosphoric acid or treated with self-etching primer, and then the modified resin was applied to the treated enamel for bonding with orthodontic brackets. The shear bond strength was measured before and after the specimens were subjected to 10,000 thermal cycles between 5 °C and 55 °C. Using TCP/CaF₂-modified resins, the shear bond strength decreased significantly after thermal cycling in phosphoric acid etched specimens but did not change significantly after thermal cycling in self-etching primed specimens. Moreover, in the self-etching primed specimens, no significant differences in shear bond strength were detected among the different TCP/CaF₂-modified resins after thermal cycling. Phosphoric acid etched specimens showed enamel fracture upon debonding of orthodontic bracket. On the contrary, no enamel fracture was recognized in self-etching primed specimens. The addition of TCP/CaF₂ tended to be associated with more residual resin on the tooth surface after debonding, which suggests a lower risk of enamel fracture. TCP/CaF₂-modified resin used with self-etching primer appears to allow easy and safe debonding of orthodontic brackets without loss of adequate bracket bond strength.     

Monomer composition and bond strength of light-cured 4-META opaque resin

A light-cured opaque resin was prepared with 4-(2-methacryloxyethoxycarbonyl) phthalic anhydride (4-META), bifunctional methacrylates, and titanium dioxide (TiO2). The relation between monomer composition and bond strength was examined with seven methacrylate monomers. Methyl methacrylate (MMA) was useful as a solvent of 4-META. However, it was not sufficiently cured by photo-initiator. The bond strength of a triethyleneglycol dimethacrylate (TEGDMA)-based composition was superior to other monomer-based compositions after repeated thermocycles. 1,6-bis(methacryloxy-2-ethoxycarbonyl-amino)-2,4,4-trimethylhex ane (UDMA) effectively provided viscosity to the composition. The prepared opaque resin consisted of 4-META/MMA-TEGDMA primer, TEGDMA-UDMA-based monomer, and titanium dioxide. This opaque resin bonded strongly to alumina-blasted cobalt-chromium alloy. The light-cured 4-META opaque resin may be useful for bonding prosthodontic composite to metal frameworks.     

Bonding of silver-palladium-copper-gold alloy with thiol derivative primers and tri-n-butylborane initiated luting agents

summary This in vitro study evaluated the effect of two primers on bond strengths and durability of luting agents joined to a silver-palladium-copper-gold alloy. One primer (Metal Primer) contained methacryloyloxyalkyl thiophosphate derivative (MEPS). The other primer (V-Primer) contained 6-(4-vinylbenzyI- n -propyl)aniino-l,3,5-triazine-2,4-dithiol (VTD). The luting agent was a methyl methacrylate (MMA)-based adhesive resin that contained 4-methacryloyloxyethyl trimellitate anhydride (4-META) and was initiated with tri- n -butylborane derivative (TBB). In order to evaluate the function of 4-META, MMA-TBB resin without 4-META was used as a control. The alloy specimens were bonded with six combinations of two primers and two luting agents. Shear bond strengths were determined before and after thermocycling. Both primers significantly elevated the bond strengths of the luting agents joined to the alloy. For unprimed groups, 4-META resin showed a more durable bond than did MMA-TBB resin. Combined use of Metal Primer with 4-META resin reduced the bond strength, while combination of V-Primer and 4-META resin did not affect the bond strength.     

Adhesive 4-META/MMA-TBB opaque resin with poly(methyl methacrylate)-coated titanium dioxide

An adhesive opaque resin for veneering on cast metal was developed with 4-methacryloxyethyl trimellitate anhydride and poly (methyl methacrylate)-coated titanium dioxide prepared by aqueous phase polymerization. The opaque resin was a modified 4-META/MMA-TBB resin. The powder consisted of 20% of the encapsulated material and 80% PMMA instead of pure PMMA powder. This resin hides the metal color when the thickness of the resin is as thin as 50 microns. The opaque resin bonded strongly to both cobalt-chromium alloy and visible-light-cured veneering resin. This self-curing opaque resin is applicable not only for bonding veneering resin to an alloy surface but also for bonding fixed partial dentures to enamel surfaces.     

Tensile bond strength of 4-META/MMA-TBB resin to ground bovine enamel using a self-etching primer

The purpose of this study was to examine the effectiveness of self-etching primer in adhering 4-META/MMA-TBB resin to bovine enamel. In this study, we designed an original self-etching primer which contained an aqueous mixture of 4-MET, 35 wt% HEMA, and ferric chloride. The polished bovine enamel surface was treated with self-etching primer for 30 seconds. Tensile bond strength of 4-META/MMA-TBB resin to enamel was measured after 1-day immersion in water at 37 degrees C. The self-etching primer containing 30 wt% 4-MET and 35 wt% HEMA (4MET30) gave a significantly higher bond strength of 11.2+/-2.8 MPa than other self-etching primers. The addition of ferric chloride into 4MET30 primer significantly decreased tensile bond strength. SEM observation revealed that 4MET30 treatment produced no distinct dissolution on enamel. When compared with phosphoric acid etching, the self-etching primer containing 30 wt% 4-MET and 35 wt% HEMA was more superior in adhering 4-META/MMA-TBB resin to enamel.     

Modification of 4-META/MMA-TBB resin for safe debonding of orthodontic brackets--influence of the addition of degradable additives or fluoride compound

The purpose of this study was to evaluate the performance of modified 4-META/MMA-TBB resin cements (Superbond C&B) in terms of debonding orthodontic brackets easily and safely from enamel without the loss of proper bracket bond strength. Poly (DL-lactide-co-glycolide) (PLGA), calcium fluoride (CaF2), or alpha-tricalcium phosphate (alpha-TCP) was added to the polymer powder of 4-META/MMA-TBB resin, and the shear bond strength of orthodontic brackets to human enamel using modified resins was measured before and after 10,000-cycle thermal cycling test between 5 degrees C and 55 degrees C. The modified resins tended to provide lower bond strength compared with the original 4-META/MMA-TBB resin. However, alpha-TCP- or CaF2-modified resin showed no significant differences in bond strength before and after thermal cycling. Moreover, there was a tendency of more residual resin remaining on the tooth surface after debonding, thereby suggesting a lower risk of enamel fracture. In conclusion, alpha-TCP- or CaF2-modified 4-META/MMA-TBB resin seemed to allow easy and safe debonding of orthodontic brackets without loss of proper bracket bond strength.     

Improved bonding of adhesive resin to sintered porcelain with the combination of acid etching and a two-liquid silane conditioner

This study determined the bond strengths of adhesive resins joined to a feldspathic porcelain (VMK 68) for the purpose of developing the most durable surface preparation for the porcelain. Three porcelain surfaces-ground, air-abraded with alumina, and etched with hydrofluoric acid-were prepared. A two-liquid porcelain conditioner that contained both 4-methacryloyloxyethyl trimellitate anhydride (4-META) and a silane coupler (Porcelain Liner M) was used as the priming agent. Each of the two liquid components of the conditioner was also used individually in order to examine the effects of the respective chemical ingredients on adhesive bonding. Two methyl methacrylate (MMA)-based resins initiated with tri-n-butylborane (TBB) either with or without 4-META (MMA-TBB and 4-META/MMA-TBB resins) were used as the luting agents. Shear bond strengths were determined both before and after thermocycling. Shear testing results indicated that thermocycling was effective for disclosing poor bonding systems, and that both mechanical and chemical retention were indispensable for bonding the porcelain. Of the combinations assessed, etching with hydrofluoric acid followed by two-liquid priming with the Porcelain Liner M material generated the most durable bond strength (33.3 MPa) for the porcelain bonded with the 4-META/MMA-TBB resin (Super-Bond C&B).     

FGF-2 release and bonding/physical properties of 4-META/MMA-based adhesive resins incorporating small FGF-2-loaded polymer particles

ObjectivesNon-biodegradable particles comprising hydroxyethyl methacrylate (HEMA) and trimethylolpropane trimethacrylate (TMPT) have been reported as useful carriers for fibroblast growth factor-2 (FGF-2). They have also been successfully incorporated into the 4-[2-(methacryloyloxy)ethoxycarbonyl]phthalic anhydride/methyl methacrylate-tri-n-butyl borane (4-META/MMA-TBB) resin to promote tissue regeneration. However, smaller particles are required to obtain restorative materials acceptable for clinical use. The aim of this study was to investigate the ability of the 4-META/MMA-TBB resin that comprises small FGF-2-loaded particles to release FGF-2 and promote cell proliferation. In addition, the bonding and physical properties of the experimental resin were evaluated.MethodsThe small particles loaded with FGF-2 were newly fabricated and incorporated into the commercial 4-META/MMA-TBB resin. Release profiles of FGF-2 from the experimental resins were assessed, and the cell proliferation cultured with the eluate was evaluated. The bonding and physical properties of the resins were evaluated using shear bond strength and three-point bending tests, and by measuring the curing time, water absorption, and water dissolution.ResultsSustained release of FGF-2 from the experimental resins for two weeks was observed, and the released FGF-2 was demonstrated to promote cell proliferation. All bonding and physical properties of the 4-META/MMA-TBB resins were found acceptable for clinical use.SignificanceThe small FGF-2-loaded particles incorporated into the 4-META/MMA-TBB resin had the same abilities to release FGF-2 and proliferate cells, as those exhibited by the conventionally sized particles. In addition, there were no adverse influences on bonding and physical properties, suggesting that the bioactive adhesive resin was acceptable for clinical use.     

Antibacterial activity and shear bond strength of 4-methacryloxyethyl trimellitate anhydride/methyl methacrylate-tri-n-butyl borane resin containing an antibacterial agent

OBJECTIVE: To produce an antibacterial adhesive for orthodontic bonding without compromising the mechanical property. MATERIALS AND METHODS: We added benzalkonium chloride (BAC) to the Superbond C&B (4-methacryloxyethyl trimellitate anhydride/methyl methacrylate-tri-n-butyl borane [4-META/MMA-TBB]), a resin that exhibits a strong bonding strength between enamel and bracket. BAC concentrations in the BAC composites were 0.25%, 0.75%, 1.25%, 1.75%, 2.5%, and 5% (wt/wt). Antibacterial activity of the BAC composite was measured by the disk diffusion method. BAC-composite discs were placed on the surface of the agar inoculated with Streptococcus mutans and Streptococcus sobrinus, and the plates were incubated at 37 degrees C. After 48 hours of incubation, the inhibition zone around each sample was measured and recorded. The BAC-modified composite was used to bond metal brackets to the phosphoric acid-etched enamel surface of human premolars. The shear bond strengths were measured after immersion in water at 37 degrees C for 24 hours. RESULTS: The BAC-composite samples showed significant (P < .0001) antibacterial activity compared with the control. Measurable zones of bacterial inhibition increased as the BAC content in test samples increased. The shear bond strength declined with the increase in BAC concentration in the composite. A significant difference was found between the control composite and composites containing 1.25%, 1.75%, 2.5%, and 5% BAC (P < .05). No significant difference was found between the control composite and composites containing 0.25% and 0.75% BAC. However, shear bond strengths of the modified composites ranged from 10.12 MPa to 20.94 MPa. CONCLUSIONS: These results confirmed that BAC-modified 4-META/MMA-TBB resin has a possibility for clinical application as an orthodontic bonding adhesive.     

Shear bond strength of an autopolymerizing repair resin to injection-molded thermoplastic denture base resins

Abstract

Objective. This study investigated the shear bond strength of an autopolymerizing repair resin to injection-molded thermoplastic denture base resins. Materials and methods. Four injection-molded thermoplastic resins (two polyamides, a polyethylene terephthalate copolymer and a polycarbonate) were used in this study. The specimens were divided into eight groups according to the type of surface treatment given: (1) no treatment, (2) air abrasion with alumina, (3) dichloromethane, (4) ethyl acetate, (5) 4-META/MMA-TBB resin, (6) alumina and 4-META/MMA-TBB resin, (7) tribochemical silica coating or (8) tribochemical silica coating and 4-META/MMA-TBB resin. Half of the specimens in groups 1, 5, 6 and 8 were thermocycled for 10,000 cycles in water between 5–55°C with a dwell time of 1 min at each temperature. The shear bond strengths were determined. Results. The shear bond strengths to the two polyamides treated with alumina, dichloromethane and ethyl acetate and no treatment were very low. The greatest post-thermocycling bond strengths to polyamides were recorded for the specimens treated with tribochemical silica coating and 4-META/MMA-TBB resin (PA12: 16.4 MPa, PACM12: 17.5 MPa). The greatest post-thermocycling bond strengths to polyethylene terephthalate copolymer and polycarbonate were recorded for the treatment with alumina and 4-META/MMA-TBB resin (22.7 MPa, 20.8 MPa). Conclusion. Polyamide was exceedingly difficult to bond to an autopolymerizing repair resin; the shear bond strength improved using tribochemical silica coating followed by the application of 4-META/MMA-TBB resin. Both polyethylene terephthalate copolymer and polycarbonate were originally easy to bond to an autopolymerizing repair resin. However, with 4-META/MMA-TBB resin, the bond was more secure.     

Development of an easy-debonding orthodontic adhesive using thermal heating

We produced experimentally a new bonding material that consisted of a mixture of a base resin (4-META/MMA-TBB resin adhesive) and thermoexpandable microcapsules for safe, easy debonding. Microcapsules in the base resin would start expansion at 80 degrees C, leading to a remarkable decrease in bond strength. Stainless steel brackets were bonded to bovine permanent mandibular incisors using bonding materials containing the microcapsules at different contents. After thermal cycling or heating, the shear bond strength of the brackets was measured. Shear bond strength of the bonding materials containing 30-40 wt% microcapsules decreased to about one-third or one-fifth that of the base resin on heating. Heating the brackets for eight seconds increased the temperature in the pulp chamber by 2 degrees C, which should not induce pulp damage. Results obtained suggested that the new bonding material should prove useful for removing brackets easily at the time of bracket debonding without any pain or enamel cracks, while maintaining the bonding strength during active orthodontic treatment.     

New mechanical retention method for resin and gold alloy bonding.

OBJECTIVE: The purpose of this study was to improve adhesion between dental adhesive resins and 14K gold alloy by creating a sponge-like structure on the alloy surface which enhanced mechanical bonding. METHODS: The internal oxidation particles of Cu oxides precipitated on a 14K gold alloy surface after high-temperature oxidation at 800 degrees C in air were removed by pickling with an acid solution to create a sponge-like structure on the alloy surface. A PMMA resin containing 4-META as an adhesive monomer and a self-cured resin without 4-META were used to examine the effects of mechanical and chemical factors on bond strength. A thiophosphate-type metal primer (M-Primer II) was used in combination with 4-META resin to strengthen the chemical bonding of 4-META resin to the porous alloy surface. The surfaces of the alloy specimen treated by oxidation, pickling, and bonding with 4-META resin were analyzed using an electron probe X-ray micro-analyzer. RESULTS: SEM observation showed many resin tags on the resin side of the bond structure after removal of the gold alloy matrix with aqua regia. The bond strength of 4-META resin to the porous alloy surface was 38+/-3 (mean+/-SD) MPa whereas that to a flat alloy surface with the same composition was 19+/-1 MPa. The bond strength of a self-cured resin without 4-META to the porous alloy surface was 24+/-2 MPa. SIGNIFICANCE: A high bond strength was obtained when 4-META resin was bonded to the porous 14K gold alloy surface treated with M-Primer II.     

Durability of adhesion between 4-META/MMA-TBB resin and cementum

4-META/MMA-TBB resin has shown good biocompatibility and remarkable adhesion to dentin. It seems to be suitable for use in periodontal tissues for retrograde root sealing and treatment of vertically fractured roots. For an adhesive resin to be useful clinically, it must bond not only to the dentin but also to the cementum. The purpose of this study was to evaluate the long-term adhesion durability of 4-META/MMA-TBB resin to cementum kept in water at 37 degrees C. Bovine root cementum and dentin surfaces were treated with 10-3 solution before 4-META/MMA-TBB resin was applied on treated surfaces. The micro-tensile bond strength (microTBS) decreased during the first two months; dye leakage value increased during the first four months and stabilized thereafter. No significant differences in adhesion durability were recognized between the dentin and cementum.     

Shear bond strengths of polymethyl methacrylate to cast titanium and cobalt-chromium frameworks using five metal primers

STATEMENT OF PROBLEM: Poor chemical bonding of a denture base resin to cast titanium frameworks often introduces adhesive failure and increases microleakage. PURPOSE: This study examined the shear bond strengths of a denture base resin to cast pure titanium, Ti-6Al-4V, and a cobalt-chromium alloy using various adhesive primers. MATERIAL AND METHODS: Disks (6.0 mm diameter, 2.5 mm thick) were cast of the 3 alloys. The disk surfaces were grit-blasted with 50 microm alumina and treated with 5 different metal primers (Metal Primer II ?MP]; Cesead Opaque primer ?OP]; Meta Base ?MB]; experimental primer ?EP]; Siloc bonding system ?SI]). A denture base resin (Palapress Vario) was then applied on the disks with hole-punched sticky tape (bonding area of 5.0 mm) and a Teflon (PTFE, New Age Industries Inc, Willow Grove, Pa.) ring (6.0 mm diameter x 2.0 mm thick). Specimens without primer were also prepared as controls. All specimens were immersed in 37 degrees C water and thermocycled up to 2,000 cycles. Shear bond strength values were determined at a crosshead speed of 0.5 mm/min. Data were statistically analyzed using 3-way ANOVA, followed by 1-way ANOVA and the Scheffé multiple range test. RESULTS: Primers significantly (P <.05) improved shear bond strengths of denture base resin to all metals, among which no significant differences were found. Specimens primed with OP, MP, and EP showed higher bond strengths than did those primed with MB. After thermocycling, the bond strengths of MB and SI decreased substantially; MB showed the least durability (22.8% to 35.5% decrease) among the primers. CONCLUSION: The application of 5 primers significantly improved the shear bond strengths of a denture base resin to cast CP titanium, Ti-6Al-4V, and Co-Cr alloy. OP and MP primers exhibited greater bond strength and durability than did MB and SI.