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PubMed2006

In-vitro shear bond strength of self-etching versus traditional adhesives for orthodontic luting.

OBJECTIVE: To determine the enamel shear bond strength (SBS) of various established (Resulcin Aqua Prime & Monobond N [RA], Prompt L-Pot III [PLP]) and experimental (AC-Bond [AC], AC-Bond + Desensitizer [ACD]) self-etching adhesives in comparison to fourth (Total Etch, Primer and Bonding have separate liquids; OptiBond FL [FL]) and fifth-generation (Total Etch, Primer and Bonding "One Bottle"; Excite [EX], Gluma Comfort Bond [CB]) adhesives. MATERIALS AND METHODS: All adhesives were applied on flattened human enamel surfaces following the manufacturers' instructions and light-cured using a quartz-tungsten-halogen curing device. 3.5 x 2.0 mm Tetric Ceram A2 composite cylinders were sheared off (Zwick Universal-testing-machine 1445, 1 mm/min) after thermocycling (5-55 degrees C, 5000x). Normal distribution was tested for all groups and analysis of variance was conducted. The t-test (5% level, Bonferroni-correction) was used for statistical analysis to evaluate intergroup differences. RESULTS: Shear bond strength in enamel: Resulcin Aqua Prime & Monobond N: 27.0 +/- 5.8 MPa, Prompt L-Pop III: 15.9 +/- 3.4 MPa, AC-Bond: 28.1 +/- 4.4 MPa, AC-Bond + Desensitizer: 22.2 +/- 4.1 MPa, OptiBond FL: 33.2 +/- 3.2 MPa, Excite: 30.5 +/- 5.1 MPa, Gluma Comfort Bond: 30.1 +/- 3.7 MPa. OptiBond FL demonstrated significantly higher SBS (p < 0.002) in enamel than Resulcin Aqua Prime & Monobond N, AC-Bond, AC-Bond + Desensitizer and Prompt L-Pop III. Resulcin Aqua Prime & Monobond N performed significantly better than Prompt L-Pop III, but did not differ from AC-Bond or AC-Bond + Desensitizer. The SBS values of Excite and Gluma Comfort Bond were both on the same level of significance as AC-Bond and Resulcin Aqua Prime & Monobond N, but the former showed superior results to AC-Bond + Desensitizer and Prompt L-Pop III. Prompt L-Pop III yielded significantly lower SBS-values than all the other products evaluated. CONCLUSION: Resulcin Aqua Prime & Monobond N and AC-Bond did not differ significantly from established 5th-generation products. Further in-vivo studies are required to investigate intra-oral stability and resistance against changing forces and force directions.

Adhesiveness↗
PubMed2005

Micro-shear bond strength of five single-step adhesives to dentin.

The micro-shear bond strengths (MSBSs) of five single-step self-etch adhesives (Adper Prompt L-Pop [APL], AQ Bond plus [AQP], OBF-2 [OB2], Reactmer Bond [RB], and Xeno III [XIII]) were compared with that of a two-step self-etch adhesive, Clearfil SE Bond [SE]. The adhesives were applied on dentin surfaces, according to manufacturers' instructions, for bonding of resin composite to dentin. After 24 hours, a micro-shear bond test was carried out and the data were analyzed by one-way ANOVA and Bonferroni test (p<0.05). The mean MSBSs in MPa were APL: 22.8, AQP: 37.4, OB2: 34.7, RB: 28.3, XIII: 30.3, and SE: 47.2. Among the single-step adhesives, the MSBS of AQP and OB2 were significantly higher than APL (p<0.05). In conclusion, the single-step adhesives used in this study, apart from AQP, produced significantly lower MSBS than the two-step adhesive (p<0.05).

Acid Etching, Dental↗
PubMed2002

Shear bond strengths of plastic brackets with a mechanical base.

This study compares the shear bond strengths of plastic brackets with a mechanical base and metal brackets using two different adhesives, and examines the modes of failure using a scanning electron microscope (SEM). Forty extracted human premolars were selected for bonding. Two types of brackets: metal and plastic-Spirit MB, and two orthodontic adhesives: System 1 + and Enlight, were used. After bonding, all samples were put into a 37 degrees C distilled water bath for 24 hours before shear bond strengths were tested. The bond strengths of the plastic brackets were significantly lower than those of the metal brackets (P < .0001). There was a statistically significant difference in bond strengths between System 1 + and Enlight for plastic brackets (P < .05), but not for metal brackets. The modes of failure predominantly occurred at the enamel/adhesive interface in the metal bracket-System 1 + group, within the adhesive in the metal bracket-Enlight and plastic bracket-System 1 + groups, and at the bracket/adhesive interface in the plastic bracket-Enlight group.

Bicuspid↗
PubMed2006

Effect of light-tip distance on the shear bond strengths of resin-modified glass ionomer cured with high-intensity halogen, light-emitting diode, and plasma arc lights.

INTRODUCTION: The purpose of this study was to assess the effect of light-tip distance on the shear bond strength and the failure site of brackets cured with 3 light-curing units (high-intensity halogen, light-emitting diode, and plasma arc). METHODS: One hundred thirty-five bovine mandibular permanent incisors were randomly allocated to 9 groups of 15 specimens each. Stainless steel brackets (Victory Series, Unitek/3M, Monrovia, Calif) were bonded with a resin-modified glass-ionomer (Fuji Ortho LC, GC Europe, Leuven, Belgium) to the teeth, and each curing light was tested at 3 distances from the bracket: 0, 3, and 6 mm. After bonding, all samples were stored in distilled water at room temperature for 24 hours and subsequently tested for shear bond strength. RESULTS: When the 3 light-curing units were compared at a light-tip distance of 0mm, they showed no significantly different shear bond strengths. At a light-tip distance of 3 mm, no significant differences were found between the halogen and plasma arc lights, but both lights showed significantly higher shear bond strengths than the light-emitting diode light. At a light-tip distance of 6 mm, no significant differences were found between the halogen and light-emitting diode lights, but both showed significantly lower bond strengths than the plasma arc light. When the effect of the light-tip distance on each light-curing unit was evaluated, the halogen and light-emitting diode lights showed no significant differences among the 3 distances. However, the plasma arc light produced significantly higher shear bond strengths at a greater light-tip distance. No significant differences were found among the adhesive remnant index scores of the various groups, except with the LED light at a distance of 3 mm. CONCLUSIONS: In hard-to-reach areas, the plasma arc curing light is suggested for optimal curing efficiency.

Acrylic Resins↗
PubMed1994

Shear bond strength of composite to enamel and dentin using Scotchbond Multi-Purpose.

A laboratory study was conducted to determine the shear bond strength to enamel and dentin using the Scotchbond Multi-Purpose dental adhesive system. High shear bond strengths of P50 composite to both human enamel (26.8 +/- 5.2 MPa) and bovine enamel (24.8 +/- 4.1 MPa) were found when the system was used according to manufacturer's directions. The mean bond strength for human dentin (25.5 +/- 7.5 MPa) was also similar to that found for bovine dentin (23.4 +/- 4.9 MPa). Variations in the recommended application technique were examined on bovine dentin. Extreme air drying of the primer slightly reduced the mean shear bond strength (19.7 +/- 6.4 MPa), while a significant reduction was observed when the adhesive resin was aggressively air-thinned (10.1 +/- 6.6 Mpa).

Acid Etching, Dental↗
PubMed1999

Shear bond strength of composite resin and amalgam adhesive systems to dentin.

PURPOSE: To determine the effects of several multi-purpose dental adhesive systems on the shear bond strength of both composite resin (Herculite XRV) and amalgam (Tytin) to dentin. MATERIALS AND METHODS: 160 extracted human molar teeth were randomly assigned to 16 treatment groups (n = 10/group), embedded in resin, and ground flat on both the occlusal and apical surfaces to expose a 3.0 mm thickness of dentin. In each specimen, a 3.18 mm diameter channel was drilled through the dentin perpendicular to the ground surface. The cylindrical preparations were treated with one of seven adhesive systems or one of two controls (37% H3PO4 or Copalite varnish) according to manufacturers' recommendation, then restored with either composite resin or amalgam. Specimens were thermocycled and subjected to a punch-out shear force using a materials testing machine. RESULTS: All examined multi-purpose adhesive systems provided increased shear bond strength in comparison to the controls. Although the individual performance of each adhesive system varied with specific restorative materials, OptiBond FL demonstrated the highest mean shear bond strength to both composite resin and amalgam. Mean amalgam shear bond strength was significantly greater than mean composite resin strengths.

Acid Etching, Dental↗
PubMed2002

Shear bond strength of a new dental adhesive used to bond brackets to unetched enamel.

The aims of the present study were to measure the shear bond strength of a new multipurpose dental adhesive, IntegraCem, for direct bonding of stainless steel and ceramic brackets to unetched enamel, and to determine the mode of bond failure. Both stainless steel and ceramic brackets (GAC) were bonded with IntegraCem to unetched extracted human premolars. After bonding, the teeth were either stored in a water bath at 37 degrees C for 3 days or passed 2500 thermocycles from 6 to 60 degrees C. Debonding was then performed with a shearing force using an Instron universal testing machine. The force was recorded at bond failure. The results showed that the shear bond strength achieved was between 6.7 and 10.8 megapascals (MPa). Bond failure occurred at the enamel-adhesive interface, enabling more efficient enamel clean up. The shear bond strengths measured suggest that IntegraCem adhesive may be effectively used in orthodontic treatment.

Acid Etching, Dental↗
PubMed2006

Shear bond strength and residual adhesive after orthodontic bracket debonding.

OBJECTIVE: To compare the shear bond strength and determine the area of residual adhesive on teeth after the debonding of brackets bonded with two types of orthodontic adhesives. These were a resin-modified glass ionomer cement (RMGIC; Fuji ORTHO LC, GC Corporation, Tokyo, Japan) and a resin applied as a precoated bracket (APC bracket, 3M Unitek GmbH, Seefeld, Germany). MATERIALS AND METHODS: A total of 60 premolar teeth were randomly divided into two groups, and brackets were bonded according to the manufacturers' instructions. In group 1, the teeth were conditioned using 10% polyacrylic acid, and the brackets were bonded using Fuji Ortho LC in wet condition. In group 2, the teeth were etched using 37% phosphoric acid, and the APC brackets were bonded. Bond strength was measured using a testing instrument (2000S, Lloyds Instruments, Fareham, England) at a crosshead speed of 1 mm/min, and the residual adhesive was quantified using a three-dimensional laser scanning instrument. RESULTS: The Mann-Whitney test showed that the median bond strength of group 1 was significantly lower than that of group 2 (P < .001). A Pearson chi-square test of the Adhesive Remnant Index (ARI) revealed a significant difference among the groups tested. All the adhesives in group 1 failed at the enamel/adhesive interface (100%), whereas group 2 exhibited cohesive failure of the adhesive (90%). CONCLUSIONS: The bond strength values obtained with the RMGIC were above the minimum values suggested in the literature to achieve a clinically effective adhesion in orthodontics.

Acid Etching, Dental↗
PubMed1994

Shear bond strengths of composite to chlorhexidine-treated enamel.

This study determined the shear bond strength (SBS) of composite bonded to chlorhexidine-treated enamel and untreated enamel. Fifty human molars were mounted in cold- cure acrylic and the superficial enamel of the buccal or lingual surface was exposed using 600-grit silicon carbide paper. During the experimental protocol, the control group (n = 25) and the experimental group (n = 25) were stored in distilled water at 37 degrees C. The experimental group was immersed in 0.12% chlorhexidine gluconate for 1 minute, 4 times daily, for 7 days. Prisma APH composite was then bonded to all samples following acid etching for 30 seconds, and the SBS was determined. Shear bond strengths for the control (13.23 +/- 3.22 MPa) and the experimental (13.67 +/- 4.59 MPa) groups were not significantly different using a t-test. The result may be attributed to either a lack of effect of chlorhexidine or to the acid etch which dissolves the affected superficial enamel leaving an unaffected substrate for bonding.

Acid Etching, Dental↗
PubMed2004

Effect of blood contamination on shear bond strength of brackets bonded with conventional and self-etching primers.

This study assessed the effect of blood contamination on the shear bond strength and bond failure site of 2 different orthodontic primers (Transbond XT and Transbond Plus Self-Etching Primer, both from 3M Unitek, Monrovia, Calif) used with adhesive-precoated brackets. Four different enamel surface conditions were tested: (1) dry, (2) blood contamination before priming, (3) blood contamination after priming, and (4) blood contamination before and after priming. Noncontaminated enamel surfaces had the highest bond strengths for both conventional and self-etching primers, which produced almost the same strength values. Under blood-contaminated conditions, both primers showed significantly reduced shear bond strengths. For the conventional primer, no significant differences were reported among the blood-contaminated groups, whereas when the self-etching primer was used, condition 4 reduced significantly the bond strength values. Significant differences in debond locations were found among the groups bonded with the 2 primers under the various enamel surface conditions.

Acid Etching, Dental↗
PubMed2005

Micro-shear bond strength and morphological analysis of a self-etching primer adhesive system to fluorosed enamel.

PURPOSE: The aim of this study was to evaluate micro-shear bond strength and morphological analysis of a self-etching primer adhesive system to fluorosed enamel. MATERIALS AND METHODS: Extracted human molars were classified according to the severity of fluorosis using Thylstrup and Fejerskov index into four groups (TFI: 0, normal; 1-3, mild fluorosis; 3-6, moderate fluorosis; 6-7, severe fluorosis) and divided into following two sub-groups. For the first sub-group, a self-etching primer adhesive system was applied to the ground enamel surfaces and the other sub-group was conditioned with 37% phosphoric acid for 30s prior to application of the same adhesive system. Teeth were then restored with a resin composite, stored for 24h in water and micro-shear bond strengths were measured. After shear testing, the fracture modes were observed under a laser scanning microscope. Morphological study of etching patterns and adhesive interface was done under a scanning electron microscope (SEM). The data were analyzed using two-way ANOVA and Sheffe test (p=0.05). RESULTS: No statistically significant difference was there between the different degrees of fluorosis in each sub-group. However, significant difference in the bond strengths between phosphoric acid etching and self-etching was found in moderate and severe groups. The SEM observations showed at the resin-enamel interface, thick resin tag like extensions penetrated around 3.5 microm into the enamel etched with phosphoric acid, while self-etching primer created, 1 microm lamina like penetration. CONCLUSION: Severity of fluorosis affects the micro-shear bond strength of a self-etching bonding system to fluorosed enamel.

Acid Etching, Dental↗
PubMed1992

Comparison in shear bond strength of orthodontic brackets between five bonding systems related to different etching times: an in vitro study.

New adhesives are continuously being marketed. The adhesive-bracket bond is still the weakest point in orthodontic bonding. A new device for the measurement of shear bond strength values (SBS) of orthodontic brackets is presented in this article. With this device, five commercial products were evaluated for their SBS: Lee Bond (LB), Concise (C), Super C (SC), Achieve-no-mix (ANM), and Panavia Ex (PE). After applying Begg brackets of laminated minimesh on lower human incisors, the specimens were thermocycled. The products investigated produced high bond strengths. The products tested showed shear bond strengths that were significantly lower than those stained with PE. The application of PE yielded the highest shear values. Nevertheless, some characteristics of this product might be clinically somewhat inconvenient. There was no significant difference in shear bond strength between 15 and 60 seconds enamel etching before bond application.

Acid Etching, Dental↗
PubMedDate not supplied

Shear bond strength of Dicor using resin adhesive systems and light activated cement.

A laboratory study was conducted to determine the shear bond strength to dentin of etched and silane-treated Dicor castable ceramic glass using a resin cement and newer generation adhesive systems. Scanning electron microscopy (SEM) examinations were also completed to evaluate the failure sites. The mean shear bond strength of the control (resin cement only, no adhesive system) was 2.1 +/- 1.2 MPa. The shear bond strength values determined for the adhesive systems and resin cement are as follows: Prisma Universal Bond 2, 18.7 +/- 2.9; XR Primer/XR Bond, 16.9 +/- 6.4; Scotchbond 2, 15.8 +/- 6.2; Tenure Solution, 15.4 +/- 4.5; and Gluma, 14.8 +/- 5.5 MPa. SEM examinations of the debonded specimens attached with Prisma Universal Bond 2 and Tenure Solution showed a complex failure pattern with cohesive failure in the glass ceramic material and adhesive failure between the resin cement and the etched and silane-treated glass surface. The debonding pattern of specimens attached with XR Primer/XR Bond, Scotchbond 2 and Gluma were primarily adhesive between the dentin and resin materials. The results of this study support the use of an adhesive system in conjunction with a resin cement for placement of Dicor castable ceramic restorations.

Ceramics↗
PubMed1996

Effects of argon laser curing on dentin shear bond strengths.

Previous studies have demonstrated the ability of the argon laser to polymerize light-activated materials and improve enamel shear bond strengths. This study was conducted to evaluate the effects of the argon laser on dentin shear bond strengths of current dentin bonding systems. Argon laser (HGM Model 8) at 231 and 280 mW, 5 sec bonding agent, 10 sec composite, and a conventional curing light (Translux EC/Kulzer) at 10 sec bonding agent, 20 sec composite were used to polymerize samples of dentin bonding systems [Scotchbond Multi-Purpose Plus (3M) and Prime Bond (Dentsply/Caulk), both with TPH (Dentsply/Caulk) composite]. A flat dentin bonding site (600 grit) was prepared on the buccal surface of extracted human teeth. Twelve samples were made for each set of parameters for both laser and conventional light totaling 48 samples. Samples were stored in distilled water in light-proof containers for 24 h at 37 degrees C. Shear bond strengths (MPa) were determined for each sample on the Instron testing machine. Mean values were calculated for each set of data and ANOVA with Fisher PLSD were used for statistical analysis. The argon laser provided bond strengths that were 21-24% greater than those of the conventional curing light system.

Analysis of Variance↗
PubMed2002

Effect of nonvital tooth bleaching on resin/enamel shear bond strength.

PURPOSE: This study evaluated the effect of nonvital tooth bleaching on shear bond strength (SBS) of the composite resin/bovine enamel interface at different periods of time after bleaching. MATERIALS AND METHODS: Three hundred twenty teeth were randomly divided into four groups according to bleaching agent: SPH: sodium perborate and 30% hydrogen peroxide; SPW: sodium perborate and distilled water; CP: 37% carbamide peroxide; and PLA: distilled water (placebo). The bleaching agents in the pulp chambers were replaced every 7 days for 4 weeks. For SBS testing, each of these groups was randomly divided into four subgroups (n = 20) according to the postbleaching periods of time: 0 (baseline), 7, 14, and 21 days. At the respective time, enamel slabs were embedded in polyester resin and flattened. Composite resin cylinders (Z100/Single bond, 3M) were bonded to the enamel surface and subjected to the SBS test using a universal testing machine. RESULTS: The ANOVA and Tukey's test (alpha = 0.05) showed statistically significant differences (expressed by different letters) among the bleaching agents only at follows: PLA (a), CP (ab), SPW (ab), and SPH (b). The SPH group, showing the lowest mean value, differed significantly from the control group. At 7, 14, and 21 days, no significant differences were observed. CONCLUSION: Nonvital tooth bleaching affected the resin/enamel SBS values when sodium perborate mixed with 30% hydrogen peroxide was used.

Analysis of Variance↗
PubMed2003

Shear punch strength and flexural strength of model composites with varying filler volume fraction, particle size and silanation.

OBJECTIVE: The effect of filler volume fraction, particle size and silanation on shear punch strength, flexural strength and flexural modulus of model composites has been evaluated. METHODS: Hybrid type glass filled (0-65.2 vol%), composites some without filler silanation (30.7-51.0 vol%) and microfilled type (0-13.0 vol%) resin matrix (UDMA and EGDMA) composites (Shofu Inc., Japan) were used in the study. For the shear punch test, 10 disc specimens, 0.5mm thick and 9 mm diameter, were prepared for each composite and tested with a 3.2mm dia punch at 1.0mm/min. Flexural strength (n=10) was measured by the method outlined in ISO 4049. Data were analyzed using ANOVA and Fisher's multiple-range test. RESULTS: Shear punch strength and flexural strength increased with increasing filler content up to 52.2% for hybrid composites and between 0 and 9.1% for microfilled composites. Shear punch strength and flexural strength decreased with increasing filler volume fraction for un-silanated composites. Flexural modulus for all materials increased with increasing filler volume fraction. Hybrid composites with silanated fillers have significantly higher values of flexural strength, flexural modulus and shear punch strength than equivalent materials with un-silanated fillers. SIGNIFICANCE: The results showed that filler silanation is an important factor for determining material strength. Additions of small quantities of microfillers appeared to have a greater effect on shear strength than equivalent amounts of hybrid filler. The shear punch test may prove beneficial for routine testing of composites as specimen preparation was simple, specimen quality was easy to maintain and the results are meaningful.

Analysis of Variance↗
PubMed1992

Comparison of the shear bond strength of a light-cured glass ionomer and a chemically cured glass ionomer for use as an orthodontic bonding agent.

Light-cured glass ionomers with an initial set of 20 seconds may produce higher initial bond strengths, as well as decreased sensitivity to moisture contamination and desiccation, than chemically cured glass ionomers making them attractive for use as orthodontic bonding agents. The purpose of this study was to determine and compare the shear bond strength of stainless steel orthodontic attachments to enamel with a light-cured glass ionomer (Zionomer) tested at 60 minutes and 24 hours, and a rapidly setting chemically cured glass ionomer (Ketac-Bond) tested at 60 minutes and 24 hours. Fifty-two recently extracted human premolars were randomly divided into four groups--1-hour and 24-hour light-cured glass ionomer groups and 1-hour and 24-hour chemically cured glass ionomer groups. Stainless steel lingual buttons were bonded to prepared enamel surfaces, and the samples were placed in a water bath at 37 degrees C until ready for testing. The shear bond strength of each sample was determined with a universal testing instrument. Results from the study conclude: (1) The mean shear bond strength of the light-cured glass ionomer is greater than that of the chemically cured glass ionomer at 1 and 24 hours. (2) The mean shear bond strength of both glass ionomers increases from 1 to 24 hours. (3) The mean shear bond strength of the light-cured glass ionomer is not significantly different from 1 to 24 hours, but the shear bond strength of the chemically cured glass ionomer cement is different.(ABSTRACT TRUNCATED AT 250 WORDS)

Acid Etching, Dental↗
PubMed2006

Shear bond strength of glass-ionomer cements to air-abraded dentin.

PURPOSE: The aim of this in vitro study was to evaluate the shear bond strength of two conventional glass-ionomer cements to bovine dentin when using the air-abrasion technique for cavity preparation. MATERIALS AND METHODS: Forty bovine central incisors were selected, embedded in polyester resin, and ground until the dentin surface was exposed. The teeth were randomly assigned to four groups: I and II--rotating instrument with a carbide bur; III and IV--an air-abrasion system. Groups I and III were restored with Fuji IX and groups II and IV with Ketac Molar. A 3-mm-diameter bonding site was delimited and treated with 10% polyacrylic acid for 10 s in the Fuji IX subgroups and with 25% polyacrylic acid for 10 s in the Ketac Molar subgroups. After surface treatment, a glassionomer cylinder was prepared for each specimen, using a split bisected Teflon matrix. The finished specimens were submitted to the shear bond strength test in a universal testing machine at a crosshead speed of 0.5 mm/min. The data were analyzed using ANOVA and Scheffé statistical tests. The dentin bonding areas were analyzed under a stereoscopic optical magnifier (40X) to assess the type of failure. RESULTS: The mean (SD) shear bond strengths in MPa were: group I--3.49 (+/- 3.77), group II--7.17 (+/- 2.93), group III--7.55 (+/- 2.99), group IV--5.67 (+/- 3.90). Ketac Molar showed higher bond strength values in bur-prepared cavities, while on the air-abraded preparations, Fuji IX showed superior results. CONCLUSION: It can be concluded that the air-abrasion system used for cavity preparations may influence the bonding performance of conventional glass-ionomer cements to dentin.

Animals↗