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PubMed1992

Effect of etching time and acid concentration on resin shear bond strength to primary tooth enamel.

The present study compared the shear bond strength of two commercially available systems to human primary enamel. Ground and unground enamel was conditioned for 15 seconds with 37% phosphoric acid siliceous gel. A 60-second application was used as a standard reference. Ten percent phosphoric acid in a polymer gel was also evaluated following a 20-second application to ground and unground primary enamel. No statistically significant difference was demonstrated between the mean values determined for each group. Compared with tests on permanent enamel with the same materials and conditions, it was concluded that no statistically significant difference exists between shear bond strengths to the enamel of the two dentitions.

Acid Etching, Dental↗
PubMed2001

Does single versus stepped curing of composite resins affect their shear bond strength?

BACKGROUND: Shrinkage occurs during polymerization of all resin composites, affecting not only the physical properties of the composites but also the marginal integrity of the restoration. Stepped photo-polymerization, in contrast to single-cure photo-polymerization, is said to minimize this shrinkage. The thickness of the increments of resin composite being cured may also be a factor in final shear bond strength. This study compared the shear bond strength resulting from these two curing methods with resin composites of various thicknesses. METHODS: Resin composite in increments of 1.5, 3 and 4.5 mm thickness, cured by stepped or single-cure photo-polymerization, was bonded to human third molar dentin with either the Scotchbond Multipurpose adhesive system or the Singlebond adhesive system. Each experimental group consisted of 12 specimens. After 7 days of storage in water, shear bond strength was tested to failure, and the mode of failure was recorded. RESULTS: The thickness of the resin composite and the method of curing had no significant effect on shear bond strength for bonds mediated by Scotchbond Multipurpose adhesive, but significantly lower shear bond strength was recorded for bonds mediated by Singlebond adhesive for resin composite 4.5 mm in thickness. With thicker resin composite, there was a tendency toward a greater proportion of adhesive cohesive bond failures. CLINICAL SIGNIFICANCE: The stepped photo-polymerization system of curing appears to offer no advantages over single-cure photo-polymerization, except that the former reportedly improves marginal adaptation and reduces marginal leakage. These results suggest that increments of resin composite to be cured by either method should be no thicker than 2 mm, particularly when the bond is mediated by a single-bottle adhesive.

Bisphenol A-Glycidyl Methacrylate↗
PubMed2004

Plasma versus halogen light: the effect of different light sources on the shear bond strength of brackets.

The aim of this study was to investigate differences between plasma and halogen light polymerization in relation to the attainable shear bond strength of brackets bonded with various adhesives. 720 brackets were divided into 72 different groups of n = 10. The brackets were bonded to 240 flat polished test specimens produced from bovine teeth, Pontor MPF alloy, and extra hard plaster (type III) respectively. Transbond XT, Kurasper F or Fuji Ortho LC served as adhesives to bond either ceramic (Transcend 6000) or stainless steel brackets (Mini Uni-Twin). 50% of all brackets were bonded with a minimum layer of adhesive, and the remaining 50% with an adhesive layer thickness of 1.0 mm. In 360 cases the adhesive was polymerized with a plasma light (PAC), and in a further 360 cases with a halogen light (Optilux 401). The light curing time was 10 s with plasma light and 40 s with halogen light. After 24 h of storage in deionized water at room temperature, all brackets were subjected to a shear bond strength test according to ISO standard 10477. The measured shear bond strength did not differ significantly between the two curing light sources. The 1 mm adhesive layer thickness group showed significantly higher shear bond strengths in comparison to the minimum layer thickness group.

Dental Bonding↗
PubMed1999

Shear bond strength of composite, glass ionomer, and acidic primer adhesive systems.

The purpose of this study was to determine the shear bond strengths of orthodontic brackets bonded with one of three methods: (1) a glass ionomer adhesive with a 20% polyacrylic acid enamel conditioner; (2) a composite resin adhesive used with 37% phosphoric acid etchant and a conventional primer; or (3) the same composite resin used with an acidic primer that combines the etchant with the primer in one application. The brackets were bonded to the teeth according to one of three protocols. Group I teeth were etched with 37% phosphoric acid and bonded with Transbond XT (3M Unitek, Monrovia, Calif) following the manufacturer's instructions. Group I acted as the control group. Group II teeth were etched with an acidic primer (Clearfil Liner Bond 2. J.C. Moritta Kuraway, Japan) that contains both the acid (Phenyl-P) and the primer (HEMA and dimethacrylate) and was placed on the enamel for 30 seconds; the adhesive used to bond the brackets was Transbond XT as in Group I. Group III teeth were etched with 20% polyacrylic acid and the brackets were bonded with Fuji Bond LC (G.C. America, Chicago, Ill). A steel rod with one flattened end was attached to the crosshead of a Zwick test machine (Zwick GmbH & Co, Ulm, Germany). An occlusogingival load was applied to the bracket, producing a shear force at the bracket-tooth interface. The results indicated that the resin/phosphoric acid adhesive system (control group) provided the strongest shear bond strength x = 10.4 +/- 2.8 MPa). The glass ionomer adhesive system provided a significantly lower bond strength (x = 6.5 +/- 1.9 MPa). The least shear bond strength was present when the acidic primer was used with an orthodontic adhesive (x = 2.8 +/- 1.9 MPa). In the present study, the use of either a fluoride-releasing glass ionomer or an acidic primer in combination with an available orthodontic composite adhesive resulted in a significantly reduced shear bond strength when compared with that of the conventional composite resin adhesive system. At the present time, the orthodontist and the patient are better served by using phosphoric acid/composite resin adhesive system or other equivalent systems that provide a clinically reliable bond strength between the bracket, the adhesive, and the enamel surface.

Acid Etching, Dental↗
PubMedDate not supplied

Effect of application technique and dentin bonding agent interaction on shear bond strength.

This study evaluated the interaction of five clinical application techniques and the shear bond strength of four DBAs (OptiBond FL, Clearfil SE Bond, PQ1 and Prime & Bond NT). A hybrid resin composite (Herculite XRV restorative resin) was attached to human dentin surfaces using five application techniques: Group A--adhesive spread with a 3M brush for 30 seconds, followed by compressed air 0.5 cm from the surface for one second to remove the excess adhesive. Group B--adhesive spread with a 3M brush for 30 seconds, followed by compressed air 0.5 cm from the surface for three seconds to remove the excess adhesive. Group C--adhesive spread with 3M brush for 30 seconds, excess adhesive removed with a clean brush, two strokes side by side, no compressed air. Group D--adhesive spread with a Micro-applicator brush for 30 seconds followed by compressed air 0.5 cm from the surface for one second to remove the excess adhesive. Group E--adhesive spread with a Micro-applicator brush for 30 seconds, the excess adhesive removed with a clean brush, two strokes side by side and no compressed air. The specimens were stored in distilled water at 37 degrees C for 24 hours, followed by thermocycling between 5 degrees C and 55 degrees C for 1,000 cycles. The shear bond strengths were determined on a universal testing machine operating with a crosshead speed of 5 mm/minute. The fracture sites were examined by 20x stereo microscope to determine the type of failure that occurred during the debonding procedure. Bond strength data were compared with analysis of variance at a significance level of p<0.05. Post hoc comparisons of means were performed with t-tests with p-values adjusted for multiple comparisons. This in vitro study concluded that there was an interaction between the application technique and bonding agent tested. All DBAs utilized the one-second compressed air technique, which yielded the highest bond strengths.

Air↗
PubMed2003

Comparative study of the dental substrate used in shear bond strength tests.

The purpose of this study was to compare shear bond strength values obtained in human enamel and dentin with the values obtained in bovine teeth using two adhesive systems with different actions. Forty human tooth half-crowns and forty bovine tooth crowns were flattened to a minimum plain area of 5 mm in diameter. The samples were divided in four groups of 20 specimens each: 1) human enamel; 2) bovine enamel; 3) human dentin; 4) bovine dentin. The samples of each group were divided in 2 subgroups of 10 samples each, according to the adhesive system used: 1) Scotchbond Multi-Purpose (SBMP); and 2) Clearfil Liner Bond 2V (CLB2V) applied according to the manufacturer's recommendations. Afterwards, restorations of Z100 composite with cylindrical shape (4 mm diameter x 5 mm height) were made using a metallic mold to submit the samples to shear bond testing on an Instron universal testing machine, at a crosshead speed of 0.5 mm/min. The data were submitted to ANOVA and Tukey's test (5%). In enamel, there was no statistical difference between bovine and human teeth for SBMP (7.36 MPa, human; 8.24 MPa, bovine), nor for CLB2V (10.01 MPa, human; 7.95, bovine). In dentin, SBMP showed a statistically lower mean on human dentin (7.01 MPa) than on bovine dentin (11.74 MPa). For CLB2V, there was no statistical difference between human (7.43 MPa) and bovine (9.27 MPa) substrates.

Analysis of Variance↗
PubMedDate not supplied

The shear bond strength between luting cements and zirconia ceramics after two pre-treatments.

This study evaluated the shear-bond strength of 11 luting cements from different material classes to manufactured pre-treated zirconia ceramics (Lava: 97% ZrO2, stabilized with 3% Y2O3). In addition, the influence of the curing method on shear-bond strength was investigated. The cements examined were one zinc-phosphate cement (Fleck's zinc cement), two standard glass-ionomer cements (Fuji I, Ketac-Cem), three resin-modified glass-ionomer cements (Fuji Plus, Fuji Cem, RelyX Luting), four standard resin cements (RelyX ARC, Panavia F, Variolink II, Compolute) and one self-adhesive universal resin cement (RelyX Unicem). The ceramic surface was sand-blasted with 100-microm alumina or tribochemically coated with silica. After bonding procedure, one group was tested after 30 minutes (Time I), the other group was stored in distilled water at 37 degrees C for 14 days and subsequently thermocycled 1000 times (Time II). Statistical analysis was performed by multifactorial ANOVA models with interactions. For multiple pairwise comparisons, the Tukey method was used. After sandblasting, the highest shear-bond strength was obtained for the self-adhesive universal resin cement at 9.7 MPa (Time I) and 12.7 MPa (Time II), respectively. When using the Rocatec system, the highest values were found for one of the resin cements at 15.0 MPa (Time I) and for the self-adhesive universal resin cement at 19.9 MPa (Time II).

Analysis of Variance↗
PubMed1999

In vitro shear bond strength of adhesive to normal and fluoridated enamel under various contaminated conditions.

OBJECTIVE: This study examined the shear bond strength of bonding agents to normal or fluoridated enamel following use of weak or strong acids to prepare enamel surfaces and after contamination with a measured amount of saliva at various stages of the bonding procedure. METHOD AND MATERIALS: One hundred extracted human third molar teeth were randomly separated into 2 basic groups (normal or fluoridated teeth), then divided into 5 subgroups. Group A specimens were not contaminated. After etching, enamel surfaces were dry and clean. Group B was left with wet surfaces after etching. Group C specimens were contaminated with artificial saliva and then dried. Group D specimens were contaminated with artificial saliva, rinsed, and then dried. In group E, all enamel surfaces were left contaminated with saliva after the etching procedures (with maleic acid or phosphoric acids). Adhesive resins were applied to all enamel surfaces according to the manufacturer's instructions. The specimens were then mounted and tested to determine shear bond strength. RESULTS: If normal enamel surfaces were rinsed and dried immediately after contamination, there was no significant reduction of shear bond strength of adhesive to enamel. Specimens in group E and group C had significantly lower bond strengths than did control specimens (group A). In the fluoridated groups etched with the phosphoric acid, statistically significant reductions in bond strengths were obtained in all contamination groups and in the control group. In the fluoridated specimens, there were no statistically significant differences between any of the contamination groups and the control group when maleic acid was used. CONCLUSION: Saliva contamination may not be a risk factor for successful bonding between bonding agent and dental tissues for normal or fluoridated enamel surfaces if they are rinsed and dried immediately after contamination. Etching of normal enamel surfaces with phosphoric acid in the presence of contamination may provide higher shear bond strength than etching with maleic acid.

Acid Etching, Dental↗
PubMed2005

The effect of tooth bleaching on the shear bond strength of orthodontic brackets.

INTRODUCTION: The purpose of this study was to determine the effect of enamel bleaching on the shear bond strength of orthodontic brackets bonded with a composite adhesive. METHODS: Two protocols were used on 60 human molars. In the at-home bleaching group (n = 30), Opalescence bleaching agent (Ultradent, South Jordan, Utah), which contains 10% carbamide peroxide, was brushed onto the teeth daily for 14 days and left for 6 hours each day. Teeth in the in-office group (n = 30) were treated with Zoom! (Discus Dental, Culver City, Calif), which contains 25% hydrogen peroxide gel, and then exposed to a light source for 20 minutes; these teeth were treated twice. After bleaching, the specimens were randomly divided into equal subgroups and stored in artificial saliva at 37 degrees C for 7 or 14 days before bonding. Shear bond strength testing was performed on all teeth. The Kruskal-Wallis test for nonparametric means was used to determine whether significant differences existed between the various subgroups and an unbleached control group. RESULTS: The mean shear bond strength for the control group was 5.6 +/- 1.8 MPa. Means for the at-home groups were 5.2 +/- 3.6 MPa and 7.2 +/- 3.2 MPa for the 7- and 14-day waiting periods, respectively. Means for the in-office groups were 5.1 +/- 5.3 MPa and 6.6 +/- 2.6 MPa for the 7- and 14-day waiting periods, respectively. The Kruskal-Wallis test (X(2) = 8.089) indicated no significant differences between the 5 subgroups (P = .088). CONCLUSIONS: The results showed that in-office and at-home bleaching did not affect the shear bond strength of orthodontic brackets to enamel.

Bisphenol A-Glycidyl Methacrylate↗
PubMed1997

Shear bond strength of Dyract compomer material to dentin of primary molars.

The purpose of this study was to measure and compare the shear bond strength and fracture pattern of Dyract compomer material with and without use of PSA prime/adhesive as well as 35% phosphoric acid etching to the buccal dentin of primary first and second molars. In addition, micromorphology of the restorative surfaces opposing the tooth structure following these different surface treatments was evaluated. For shear bond strength measurement and fracture pattern evaluation, 36 extracted non-restored human primary molars with mild to moderate caries divided into 3 groups of 12 teeth each were used. Dyract with and without use of PSA prime/adhesive as well as 35% phosphoric acid etching for 15 seconds prior to placement of PSA prime/adhesive was applied to the buccal surface of exposed dentin. A standardized tube of Dyract was placed on each dentin surface and polymerized. The tubes were sheared off with a Universal testing machine at a cross head speed of 12.7 mm/min. For evaluation of the restorative surfaces opposing the tooth structure, 9 teeth divided into 3 groups of 3 teeth each were used to prepare the specimens, which were then demineralized in 10% hydrochloric acid for 24 hours. Fitting surfaces of these specimens were prepared and examined using scanning electron microscope. Tukey's multiple range test showed that the shear bond strength of Dyract with PSA prime/adhesive (group 1) was statistically significantly higher than Dyract without PSA prime/adhesive (group 2) and phosphoric acid etching (group 3). The shear bond strength in group 1 averaged 5.89 +/- 1.40 (X + SD MPa) while for groups 2 and averaged 1.49 +/- 0.69 and 3.69 +/- 0.89 respectively. Pretreatment of dentin surface with 35% phosphoric acid increased resin tags formation but it did significantly lower shear bond strength of Dyract with PSA prime/adhesive to dentin of primary molars. Bond failure patterns for all groups were only adhesive and mixed type failures.

Adhesives↗
PubMed2004

Shear bond strengths and microleakage of four types of dentin adhesive materials.

The aim of this investigation was to compare the microleakage of composite resin (Z-100) and shear bond strength to bovine dentin using different types of adhesive systems (Scotch Bond Multi-Purpose, All-Bond 2, One-Step, and Perma Quick) to compare and correlate microleakage to shear bond strength. For the microleakage aspect of the study, 20 class V were prepared (bovine incisors) with 90-degree cavosurface margins and were located at the cemento-enamel junction using a template. Each dentin bonding system was applied to five cavities following the manufacturer's instructions and restored with Z-100 composite resin. After 24 hours of storage in distilled water at 37 degrees C, the teeth were immersed in 2% basic fuchsin dye. All teeth were sectioned in a mesiodistal direction using a diamond saw, and each section was then inspected under a stereomacroscope. For the shear bond strength aspect of the study, 20 bovine incisors were centrally horizontally mounted in Teflon mold with cold cure acrylic resin. Flat labial dentin surfaces were prepared using different grit silicon carbide abrasive wheels. Five specimens were used for each of the bonding agent systems. Each specimen was bonded with restorative composite resin (Z-100) and applied to the treated dentinal surface through a split Teflon mold. All specimens were stored in distilled water at 37 degrees C for 24 hours. The bonds were stressed using shear forces at a crosshead speed of 0.5mm/min using an Instron Universal testing machine. Findings indicate none of the systems tested in this study were free from microleakage. Scotch bond multi-purpose achieved the best seal, with One-Step being second best, while All-Bond 2 and Perma Quick had the poorest seal. However, there were significant differences among the shear bond strengths of the four bonding systems tested. Scotch Bond Multi-Purpose has a higher bond strength to composite resin when compared to the other dentin adhesives. The study also concluded there is no association between microleakage and shear bond strength.

Analysis of Variance↗
PubMed2000

Effect of changing enamel conditioner concentration on the shear bond strength of a resin-modified glass ionomer adhesive.

The purpose of this study was to determine the effects on shear bond strength of changing the concentration of the enamel conditioner used with resin-reinforced glass ionomer. Shear bond strength was measured within 30 minutes after bonding. Forty-six freshly extracted human molars were collected and stored in a solution of 0. 1% (weight/volume) thymol. The teeth were cleaned and polished, then randomly separated into 2 groups. In group I, enamel was conditioned with a 10% polyacrylic acid solution before bonding. In group II, the enamel was conditioned with a 20% polyacrylic acid solution. The results of t test comparisons of the 2 experimental groups (t = 4.9) indicate significant differences (P =.001). Shear bond strength was significantly greater in the group conditioned with the 20% polyacrylic acid concentration (X = 3.3 +/- 2.6 MPa) than in the group conditioned with the 10% concentration (X = 0.4 +/- 1.0 MPa). The present findings indicated that the lower initial shear bond strength of resin-reinforced glass ionomer adhesive can be improved more than 8-fold when the concentration of the polyacrylic acid enamel conditioner is increased from 10% to 20%. The clinician needs to take these properties into consideration when ligating the initial archwires.

Acid Etching, Dental↗
PubMedDate not supplied

Shear bond strengths of one-bottle dentin adhesives using multiple applications.

This study evaluated the effect of multiple applications of the one-bottle adhesives Prime & Bond, One-Step, and Tenure Quik on the shear bond strength of composite to dentin. In addition, the study examined the effects of surface moisture and dual-cure composite on bond strengths of One-Step and Tenure Quik respectively. The adhesive systems were bonded to the occlusal dentin of extracted human teeth. Control group specimens received only two applications of adhesive, as recommended by the manufacturers. Two experimental groups of each system received a greater number of adhesive applications. Additional experimental groups using only two adhesive applications were made to test modifications in surface moisture and composite type for One-Step and Tenure Quik. Shear bond strengths were determined using an Instron Universal Testing Machine. The mean shear bond strength of the Prime & Bond control group was significantly greater than that of the other two control groups. Multiple applications of adhesive decreased the bond strength of each system, but the difference was significant only for four applications of One-Step. The method of moisture removal (compressed air or blotting) had no effect on shear bond strength of One-Step. The shear bond strength of Tenure Quik was not affected by the type of composite used. Prime & Bond had significantly higher shear bond strengths to dentin than either One-Step or Tenure Quik. Both Prime & Bond and One-Step had significantly higher bond strengths than Tenure Quik.

Analysis of Variance↗
PubMed2003

Effect of pulse vs continuous micro-xenon irradiation on the shear bond strength of a light-cured orthodontic composite resin.

The aim of the study was to evaluate the effect of pulse vs. continuous irradiation on the shear bond strength of a conventional orthodontic composite resin cured with a micro-xenon light (Aurys, Degrè K, Schiltigheim, France). Ninety freshly extracted bovine permanent mandibular incisors were randomly assigned to one of six groups; each group consisting of 15 specimens. Three groups were exposed to continuous irradiation of micro-xenon light for 10, 5, and 2 s, respectively, and used as controls. The remaining three groups were exposed to pulse irradiation of the same light source for 10, 5, and 2 s, respectively. After 24 h, all samples were tested in a shear mode on an Instron Machine (Instron Corp., Canton, MA, USA). Analysis was made by ANOVA with Scheffé's test for comparisons. The chi-square test was used to determine significant differences in the Adhesive Remnant Index scores. The mean shear bond strength of the brackets continuously cured for 10 s was not statistically different from that of the brackets pulse-activated for the same curing time. Also, no statistically significant differences were found between both groups cured for 5 s. The group pulse-activated for 5 s, however, had a significantly lower mean shear bond strength than the control group cured for 10 s. Finally, the group pulse-activated for 2 s showed significantly lower bond strength values than all the other groups tested. Compared with continuous light curing, the micro-xenon pulse activation provides similar shear bond strength values, except when used for only 2 s; but despite lower performance characteristics, the shear bond strength may be clinically acceptable.

Analysis of Variance↗
PubMed2003

Evaluation of a new CPC-to-gauge bonding technique with the use of in vitro fluid flow.

Strain gauging enables the measurement of bone deformation during physical activity, leading to a better understanding of the physiological effects of loading on bone growth and remodeling. Development of a technology that will withstand long-term in vivo exposure and bond securely to bone is imperative for accurate, consistent measurement collection. Polysulfone is currently used to attach calcium-phosphate ceramic (CPC) particles, which promote bone-to-gauge bonding, to polyimide-backed strain gauges. This study evaluated the use of an implant-grade epoxy as an alternative CPC-polyimide adhesive. Polyimide-epoxy-CPC interfaces were loaded to failure and shear strengths calculated. In vitro studies providing a constant flow of medium over test specimens were designed, and long-term in vitro fluid exposure studies of the epoxy's shear strength were conducted. Average shear strength of polysulfone-polyimide interfaces were reported to be 7 MPa. The average shear strength of the epoxy-polyimide interface before long-term in vitro exposure was 17 MPa, which is stronger than the shear strength of the bone-CPC interface. The strength of the epoxy-polyimide interface decreased to 6.8 MPa after 24 weeks in vitro and 3 MPa after 24 weeks in vivo.

Animals↗
PubMedDate not supplied

Factors affecting shear bond strength of composite resin to fluorosed human enamel.

The aim of this work was to determine the effects of age, severity of fluorosis, and etching time on the shear bond strength of direct composite resin to human enamel. A total of 117 teeth, freshly extracted from patients in areas of Saudi Arabia endemic for dental fluorosis, were classified according to age (< 40 years and 40+ years) and severity of fluorosis, using the Thylstrup and Fejerskov index, TFI: TFI = 0, TFI = 1-3, and TFI = 4-6. Cylindrical composite resin specimens 5 mm in diameter and 3 mm high were bonded to the flattened midlabial enamel surfaces etched for 60 or 120 seconds and shear bond strength measured, using the Instron Universal Testing Machine at a crosshead speed of 0.5 mm/minute. Shear bond strength of the resin varied between 11.2 +/- 3.6 and 21.6 +/- 4.1 MPa. Three-way analysis of variance and Sheffé's multiple range test showed that the severity of fluorosis had no statistically significant effect on shear bond strength (p > 0.05). However, the bond was significantly stronger in teeth from patients < 40 years old than from those 40+ years old. Furthermore, at age < 40 years, shear bond strength was significantly higher in teeth etched for 120 seconds than those etched for 60 seconds (p < 0.05), but this was not the case in teeth from the older patients. In teeth with TFI = 1-3, the mode of bond failure was predominantly mixed, but at TFI = 4-6, the bond failure was mostly cohesive in enamel at all ages and etching times. It is, therefore, concluded that both age and etching time affect the shear bond strength of composite resin to fluorosed human enamel.

Acid Etching, Dental↗
PubMed2006

Effect of various adhesive systems on the shear bond strength of fiber-reinforced composite.

INTRODUCTION: The purpose of this study was to evaluate the effect of 3 adhesive systems on the shear bond strength of a fiber-reinforced composite (FRC). METHODS: Sixty bovine permanent mandibular incisors were randomly divided into 3 groups of 20. The FRCs (Ortho, Stick Teck Ltd, Turku, Finland) were bonded to the teeth with 3 adhesive systems (Tetric Flow [Ivoclar-Vivadent, Schaan, Liechtenstein], Transbond XT [Unitek/3M, Monrovia, Calif], and Fuji Ortho LC [GC Europe, Leuven, Belgium]). After bonding, all samples were stored in distilled water at room temperature for 24 hours and subsequently tested for shear bond strength. Analysis of variance and the Sheffé post-hoc tests were used at a significance level of P < .05. RESULTS: ANOVA indicated significant differences among the various groups. Fibers bonded with Transbond XT showed significantly higher shear bond strengths than the other 2 groups. No significant differences in shear bond strength values were reported between Tetric Flow and Fuji Ortho LC. No significant differences in debond locations (ARI scores) were found among the various groups. CONCLUSIONS: For maximum bond strength, use Transbond XT for direct bonding of FRC.

Acrylic Resins↗
PubMed2004

Effect of water storage on the shear bond strength of a cyanoacrylate adhesive: clinical implications.

AIM: To compare the effects of water storage on the shear bond strength of a cyanoacrylate adhesive system at three time intervals: (1) within 30 minutes after bonding the bracket to the tooth; (2) 24 hours from the time of bonding; and (3) after 30 days of storage in water at 37 degrees C. METHODS: Sixty freshly extracted human molars were collected and stored in a solution of 0.1% (weight/volume) thymol. The teeth were cleansed and polished, then randomly separated into three groups: group 1, cyanoacrylate adhesive debonded within 30 minutes from initial bonding; group 2, cyanoacrylate adhesive debonded after 24 hours immersion in deionized water at 37 degrees C; group 3, cyanoacrylate adhesive debonded after 30 days immersion in deionized water at 37 degrees C. RESULTS: Analysis of variance (F = 11.94) comparing the experimental groups indicated the presence of significant differences between the three groups (P = .0001). The shear bond strengths were significantly greater in the two groups debonded after 30 minutes (mean = 5.8+/-2.4 MPa) and 24 hours (mean = 7.1+/-3.3 MPa) than the group debonded after 30 days of water storage (mean = 2.7+/-2.0 MPa). CONCLUSION: The present findings indicate that the cyanoacrylate adhesive has clinically adequate shear bond strengths at 30 minutes and 24 hours after initial bonding, but that the bond strength decreases by 50% within 30 days. The clinician needs to carefully take the overall properties of the adhesive into consideration.

Analysis of Variance↗