Effect of air-blowing variables on bond strength of all-in-one adhesives to bovine dentin

This study evaluated the effect of air-blowing variables on the microtensile bond strength (microTBS) of two all-in-one adhesives. A bonding agent was applied to the flat dentin surface of extracted bovine teeth, and the surface left undisturbed for 20 seconds. Gentle or intensive air-blowing was applied for five seconds, and the adhesive photopolymerized for 10 seconds. Resin composite paste was placed and cured after each bonding treatment. Specimens were subjected to microTBS test with a crosshead speed of 1.0 mm/min. Data were statistically analyzed using ANOVA, followed by Bonferroni post hoc test. When Clearfil tri-S Bond was bonded to dentin, the microTBS value of specimens applied with intensive air-blowing was significantly higher than that applied with gentle air-blowing (p<0.01). On the other hand, with Fluoro Bond Shake One, the microTBS value of specimens applied with intensive air-blowing was significantly lower than that applied with gentle air-blowing (p<0.01).     

Effect of water storage on bond strength of self-etching adhesives to dentin

AIM: The objective of this study was to evaluate the bond strength of self-etching adhesive systems one week and one year after storage in water. METHODS AND MATERIALS: Fragments from the buccal surfaces of 45 bovine teeth were prepared (12 mm in length x 5 mm in width x 1.0 mm in thickness). Dentin surfaces were wet-abraded with 600-grit SiC paper to create a standardized smear layer. Samples were randomly assigned to 18 experimental groups (n=5), according to nine adhesive systems tested (Single Bond; Adper Prompt L-Pop; iBond; One-Up Bond F; Xeno III; Clearfil SE Bond; Optibond Solo Plus SE; Tyrian SPE/One-Step Plus; and UniFil Bond) and two water-storage times (one week and one year). Adhesives were applied according to the manufacturers' instructions. Z250 composite was applied into the molds to fill up the internal diameter volume of a Tygon tubing mold (1.0 mm high/0.7 mm internal diameter). Micro-shear bond strengths were determined using an apparatus attached to an Instron Universal Testing Machine (0.5 mm/min). Data were statistically analyzed using a two-way analysis of variance (ANOVA) and the Tukey's test (5%). RESULTS: One year after water storage the dentin bond strength of all adhesive systems reduced significantly, except for One-Up Bond F. CONCLUSION: Water-storage time decreased the bond strength for most dentin bonding agents tested.     

Influence of air abrasion and long-term storage on the bond strength of self-etching adhesives to dentin

This study tested the effects of long-term storage and aluminum oxide air abrasion on the bond strength of self-etching adhesive systems. Extracted human third molars were ground flat with 600-grit SiC paper to expose middle coronal dentin. Clearfil SE Bond and One-Up Bond F were applied to dentin surfaces in accordance with manufacturers instructions with or without previous aluminum oxide 50 microm air abrasion. A crown was built up with the resin composite TPH Spectrum and the specimens were stored in water for 24 hours. The bonded assemblies were vertically sectioned into beams for microtensile bond testing. The beams of each tooth were individually immersed in bottles containing water at 37 degrees C for one day, three and six months; the water was changed daily. The specimens were then subjected to microtensile bond testing. The bond strength data were subjected to ANOVA and Tukey Kramer test. Fractured specimens were analyzed in a scanning electron microscope to determine failure modes. Air abrasion improved Clearfil SE Bond bond strength in the three month evaluation. No significant difference was found between the two adhesives systems, but bond strengths gradually decreased over time. Failure modes varied significantly among groups and were influenced by long-term storage and aluminum oxide air abrasion.     

Effect of air-drying time of single-application self-etch adhesives on dentin bond strength

This study examined the effect of air-drying time of adhesives on the dentin bond strength of several single-application self-etch adhesive systems. The adhesive/resin composite combinations used were: Adper Prompt L-Pop/Filtek Z250 (AP), Clearfil Tri-S Bond/Clearfil AP-X (CT), Fluoro Bond Shake One/Beautifil (FB), G-Bond/Gradia Direct (GB) and One-Up Bond F Plus/Palfique Estelite (OF). Bovine mandibular incisors were mounted in self-curing resin and wet ground with #600 SiC to expose labial dentin. Adhesives were applied according to each manufacturer's instructions followed by air-drying time for 0 (without air-drying), 5 and 10 seconds. After light irradiation of the adhesives, the resin composites were condensed into a mold (phi4x2 mm) and polymerized. Ten samples per test group were stored in 37 degrees C distilled water for 24 hours; they were then shear tested at a crosshead speed of 1.0 mm/minute. One-way ANOVA followed by Tukey's HSD tests (alpha = 0.05) were done. FE-SEM observations of the resin/dentin interface were also conducted. Dentin bond strength varied with the different air drying times and ranged from 5.8 +/- 2.4 to 13.9 +/- 2.8 MPa for AP, 4.9 +/- 1.5 to 17.1 +/- 2.3 MPa for CT, 7.9 +/- 2.8 to 13.8 +/- 2.4 MPa for FB, 3.7 +/- 1.4 to 13.4 +/- 1.2 MPa for GB and 4.6 +/- 2.1 to 13.7 +/- 2.6 MPa for OF. With longer air drying of adhesives, no significant changes in bond strengths were found for the systems used except for OF. Significantly lower bond strengths were obtained for the 10-second air-drying group for OF. From FE-SEM observations, gaps between the cured adhesive and resin composites were observed for the specimens without the air drying of adhesives except for OF. The data suggests that, with four of the single-application self-etch adhesive systems, air drying is essential to obtain adequate dentin bond strengths, but increased drying time does not significantly influence bond strength. For the other system studied, the bond strength of the non-air dried group was not significantly different from the five second drying time, but prolonged drying was very detrimental to bond strength. For all five of the systems studied, a five-second air-drying time appeared to be appropriate.     

Influence of two carbodiimides on the bond strength of universal adhesives to dentin

Odontology - The pretreatment of dentin with cross-linking agents during bonding procedures has been proposed to improve the mechanical properties of the collagen in the hybrid layer and reduce the...     

Effect of dentin adhesives on sealant bond strength.

This study evaluated the effect of four dentin adhesives on sealant shear bond strength. Five groups of 15 human extracted teeth (75 in total) were prepared to receive the following treatments: group 1, sealant only; group 2, sealant plus gluma primer; group 3, sealant plus gluma primer and sealer, group 4, sealant plus C & B Metabond. Each tooth had a bonding site prepared for each material by grinding a flat plane on the enamel with 600 grit. The enamel site was etched for 30 seconds, washed for 20 seconds and dried. Each material was mixed according to the instructions of the manufacturer. The sealant (Concise) was placed in a nylon cylinder, light-cured, stored in distilled water for 24 hours, thermocycled (100 cycles at 5 to 55 degrees C) and shear bond strength determined with a knife-edge blade in an Instron running at a crosshead speed of 0.5 mm/min. The results in MPa were: group 1, 11.8 +/- 4.5; group 2, 12.3 +/- 5.0; group 3, 10.3 +/- 1.9; group 4, 12.5 +/- 8.6; and group 5, 15.8 +/- 5.2. Statistically (ANOVA one way) there was no significant difference in the groups.     

The effect of warm air-blowing on the microtensile bond strength of one-step self-etch adhesives to root canal dentin

Purpose

The use of warm air-blowing to evaporate solvents of one-step self-etch adhesive systems (1-SEAs) has been reported to be a useful method. The purpose of this study was to evaluate the effect of warm air-blowing on root canal dentin.

Effect of light intensity for adhesives on shear bond strength to dentin

This study evaluated the effect of light intensity on the shear bond strength (SBS) of two self-etch adhesive systems: SI-R20401 (an experimental two-step) and Fluoro Bond Shake One (a commercial one-step bonding system). The adhesive systems were applied to the flat dentin surfaces of extracted human teeth according to manufacturers' instructions. Light intensities used for the adhesive systems were 100, 300, and 500 mW/cm2. A resin composite paste was placed and polymerized for 40 seconds with 600 mW/cm2 of light intensity after each bonding procedure. Specimens were subjected to SBS test with a 1.0 mm/minute crosshead speed. Data were statistically analyzed using ANOVA, followed by Bonferroni post hoc test. Two-way ANOVA showed no significant differences in the effects of the adhesive system, light intensity for appliedadhesive, and the interaction between them. Based on the results and limitations of this study, it was concluded that light intensity showed no significant effects on the SBS of the two self-etch adhesive systems.     

Effects of one-year storage in water on bond strength of self-etching adhesives to enamel and dentin

The aim of this study was to compare the bond strengths of three self-etching materials during one year of storage. Clearfil SE Bond (SE), Clearfil Protect Bond (PB), and Clearfil Tri-S Bond (TS) were used for bonding to dentin and enamel according to manufacturer's instructions. Microshear bond strength values were measured after 24 hours, six months, and one year. Two-way ANOVA showed that the interaction of material type and storage time was significant for dentin. At baseline, SE had the highest bond strength to dentin. There were no significant changes in bond strength for each material during the storage period, except for PB which showed increased bond strength to dentin after one year. All materials performed reliably after one year. However, the antibacterial and fluoride-releasing effects of PB would further contribute to the long-term clinical benefits of this material.     

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).     

Tensile bond strength of dental adhesives to dentin and enamel

This study compared the tensile bond strengths of an unfilled resin bonding agent and four proprietary dentin bonding agents to dentin and acid-etched enamel. Forty-eight hours after bonding, 10 dentin-bonded teeth and 10 enamel-bonded teeth for each material were loaded in tension in an Instron Universal Testing Machine until bond failure. The remaining specimens were stored in a water bath for six months and then tested in a similar manner. At the end of six months, Universal Bond and Tenure (3-step) had bond strengths significantly greater than those of the other agents. All bonding agents, except Tenure (3-step), showed a significant decrease in tensile bond strength to both dentin and enamel after six months (p less than 0.0001).     

Microtensile bond strength of self-etching adhesives to enamel and dentin

PURPOSE: To measure the microtensile bond strength to enamel and dentin of three self-etching adhesives in comparison with a total-etch two-step system as a control. MATERIALS AND METHODS: A total of 40 extracted human molars were stored in saline solution until use, then divided into 4 groups of 10 teeth (one group per adhesive system). Half of each of these groups underwent bond strength tests on enamel, and the other half was used for adhesion testing on dentin. The following experimental groups (n = 5) were then formed: E(1) Adper Prompt-L-Pop (AP, 3M ESPE) on enamel; E(2) Xeno CF II (X, Sanking Kogyo) on enamel; E(3) AdheSE (AS, Ivoclar-Vivadent) on enamel; E(4) Excite (EX, Ivoclar-Vivadent) on enamel; D(1) AP on dentin; D(2): X on dentin; D(3) AS on dentin; D(4) EX on dentin. Each tooth yielded 15 to 20 sticks about 0.9 x 0.9 mm in cross-sectional area for microtensile testing. Specimens were loaded in tension at a crosshead speed of 0.5 mm/minute, and bond strength at failure was calculated in MPa. A two-way ANOVA was applied to test for significance of the differences among the groups. RESULTS: The bond strength values of Excite (the control) were significantly higher than those of the test products on enamel (42.92+/-4.8 MPa) and on dentin (45.80+/-5.79 MPa). The self-etching adhesives AdheSE (28.48+/-4.71 MPa) and Xeno CF II (27.22+/-2.74 MPa) revealed significantly stronger adhesion than Adper Prompt-L-Pop (20.16+/-2.07 MPa) on dentin. On enamel, all self-etching test materials performed similarly. The substrate did not appear to have a significant influence on adhesion, as each material reached comparable levels of bond strength on enamel and dentin. CONCLUSION: On both substrates the self-etching adhesives tested performed significantly worse than did the total-etch system.     

Effect of dentin location and long-term water storage on bonding effectiveness of dentin adhesives

Dentin is a variable substrate with properties that change considerable in a single surface. The purpose of this study was to evaluate the bonding effectiveness to these different dentin locations and evaluate these differences over time. After bonding procedures with five different adhesives, small micro-tensile bond strength (μTBS) beams were prepared and dichotomously divided in 'center' and 'periphery' dentin specimens. After 1 week, 3, 6 and 12 months of water storage the μTBS of specimens of each group was determined, enabling a paired study design. The bond strengths of both etch&rinse adhesives were insensitive to regional variability. For the two-step self-etch adhesives, a marked increase in bond strengths was observed with increasing amount of intertubular dentin. Regional variability did not affect the long-term bonding effectiveness for any of the adhesives tested. In conclusion, only for the mild self-etch adhesives, μTBS to 'periphery' dentin was higher than for the 'center' specimens.     

Effect of primer dwell time on dentin bond strength

The period of time that primers are to be applied to etched dentin surfaces is sometimes clear and sometimes not indicated in the instructions accompanying the bonding system. In this study, primers with either alcohol or acetone solvents appeared to act rapidly and not show any significant improvement with extended primer dwell time. When resin adhesive primer application periods were prolonged, significant improvements in the bond strengths of some adhesives occurred. Water-based primers placed on dried etched dentin surfaces appear to require longer application times than do acetone or alcohol-based primers applied to wet etched dentin surfaces. Careful attention is required regarding the application of these materials. If in doubt about the primer application, longer primer application periods should be used.