Tetric N-Bond Universal Research Articles

Optical Evaluation of Enamel Microleakage with One-Step Self-Etch Adhesives.

In this in vitro study, cross-polarization optical coherence tomography (CP-OCT) was used to evaluate microleakage in dental composite restorations bonded to enamel with two types of one-step self-etching (SE) adhesives. One-step SE adhesives were proposed to simplify bonding of composite restorations. However, bonding of these simplified adhesive to dental enamel is still questionable. OCT is a promising diagnostic tool that allows micron-scale imaging of biological tissues and structures. Class-V cavities (4-mm diameter × 1-mm depth) were prepared on the labial surfaces of extracted human anterior teeth with margins and floor located in enamel. The cavities were then divided into two groups (n = 5) and restored with either Tetric N-Bond Universal (Ivoclar Vivadent, Liechtenstein) or Palfique Bond (Tokuyama Dental Corporation, Japan), followed by Estelite Flow Quick flowable composite (Tokuyama Dental Corporation). After storage in 100% humidity for 24 h, specimens were immersed in ammoniacal silver nitrate solution for another 24 h. Later, they were rinsed and immersed in photo-developing solution under fluorescent light for 8 h. CP-OCT at 1310 nm center wavelength was used to scan seven two-dimensional cross-sectional images from each specimen. Each cross-sectional image was analyzed using ImageJ software to quantify interfacial microleakage at the cavity floor. Student's t-test showed significant difference between the tested adhesives (p < 0.05). Palfique Bond adhesive presented inferior interfacial adaptation as it obtained higher values of floor microleakage compared to Tetric N-Bond Universal adhesive group. CP-OCT enabled nondestructive quantitative assessment of microleakage in enamel dental restorations.

Microshear bond strength of universal adhesives to dentin used in total-etch and self-etch modes

Purpose To determine the dentin bonding ability of three new universal adhesive systems under different etching modes using microshear bond strength (μSBS). Materials and methods Futurabond U, Single Bond Universal, and Tetric N-Bond Universal were used in this study. Sixty noncarious human molars were assigned to three groups based on the type of the universal adhesives. Two etching modes (total-etch and self-etch) were employed for each adhesive group. The adhesives were applied on dentin surfaces according to the manufacturer's instructions then composite resin (Z350 XT, nanocomposite) was condensed through a polyethylene tube with a 1 mm internal diameter and 2 mm height attached firmly to dentin surfaces and light cured. All samples were thermocycled for 500 cycles from 5 to 55°C. The μSBS was measured by using universal testing machine at cross-head speed of 0.5 mm/min. The bonded surfaces were examined under a stereomicroscope at magnification ×50 to determine the mode of failure. Dentin slices were prepared for each group to evaluate the resin–dentin interface a resin composite with each adhesive were placed 2 mm thick to form composite core. The segments were sectioned longitudinally and prepared to be examined under scanning electron microscope. Results Among the universal adhesives, Futurabond U and Tetric N-Bond Universal in total-etch mode showed significantly higher μSBS values than in self-etch mode. Single Bond Universal did not show any significant difference in μSBS between the total-etch mode and self-etch mode. Conclusion Performance of universal adhesives was shown to be material-dependent. The results indicate that universal adhesives used on dentine performed better in total-etch mode than self-etch mode.

Marginal fit of class II cavities restored with bulk-fill composites

Purpose To evaluate the marginal integrity of three types of bulk-fill composite resins in class II cavities. Materials and methods Simple class II cavities with parallel walls were prepared in 40 extracted human sound molars were selected. The overall dimensions and depth of the cavities were standardized as follow: 4 mm length occlusocervically, 4 mm width buccolingually and 2 mm depth axially. The teeth were randomly divided into four groups (n = 10 each): group 1: Tetric N-Bond Universal and Tetric EvoCeram Bulk Fill composite; group 2: Single Bond Universal and Filtek Bulk Fill posterior composite; group 3: Futurabond U and Admira Fusion X-Tra; group 4: Tetric N-Bond Universal and Tetric EvoCeram composite. All samples were thermocycled for 600 cycles. Impressions of the teeth were made using a polyvinyl siloxane then poured with epoxy resin. These replicas gold sputtered and examined under scanning electron microscopy. Results Group 3 recorded the lowest mean marginal gap length value, while group 4 recorded the highest mean marginal gap length value. One-way analysis of variance was used to compare the tested groups at a level of significance (P ≤ 0.001). For width of proximal gap the lowest mean marginal gap length value found in group 3, while the highest mean value of gap width proximally found in group 1. In width of cervical gap the lowest mean marginal gap length value was found in group 3, while the highest mean value of gap width cervically found in group 4. One-way analysis of variance test was used to compare the tested groups at a level of significance (P ≤ 0.05). Conclusion Admira Fusion X-Tra has good results compared to other used bulk fill and conventional composites.

Bonding Performance of Universal Adhesives to Eroded Dentin.

To evaluate the microtensile bond strength (µTBS) and nanoleakage (NL) of several universal adhesives to eroded dentin (ED), using etch-and-rinse (ER) or self-etch (SE) strategies, and to characterize the surface using two pH cycling models to erode dentin (citric acid and a soft drink). Molars were eroded either by soft-drink or citric acid cycling, or were left untreated as control (SD). For each surface, the following adhesives were applied: 1. All-Bond Universal; 2. Ambar Universal; 3. Clearfil Universal; 4. Futurabond U; 5. One Coat 7 Universal; 6. Peak Universal Bond; 7. Prime&Bond Elect; 8. Scotchbond Universal; 9. Tetric n-bond Universal, and 10. Xeno Select. After application of the composite, specimens were sectioned into composite-dentin sticks and tested under tension (0.5 mm/min). Selected sticks from each tooth were used to assess NL. The occlusal dentin surfaces after erosive cycling were examined using SEM. Data were analyzed by three-way ANOVA and Tukey's post-hoc test (a = 0.05). In ED, there was no difference in μTBS and NL between ER and SE strategies (p > 0.61). Most μTBS and NL values obtained for ED were, respectively, lower and higher than those for SD (p < 0.01), being worse for citric acid ED (p < 0.001). Citric-acid-eroded dentin showed more enlarged tubules, with partial loss of peritubular dentin when compared to soft-drink eroded dentin. The different pH cycling models reduced μTBS and increased NL of the composite/eroded-dentin interface; however, in ED, the performance of the universal adhesives did not depend on the adhesive strategy used.

Effect of dentin roughness on the adhesive performance in non-carious cervical lesions: A double-blind randomized clinical trial

ObjectiveThis double-blind randomized clinical trial evaluates the influence of dentin roughening (RO) on the clinical behavior of a new universal multi-mode adhesive (Tetric N-Bond Universal; Ivoclar-Vivadent) applied as self-etch and as etch-and-rinse in non-carious cervical lesions (NCCLs). MethodsA total of 192 restorations were randomly placed in 48 patients according to the following groups: ER – Etch-and-rinse (no preparation); SE – self-etch (no preparation); ER+RO and; SE+RO. The resin composite Empress Direct (Ivoclar-Vivadent) was placed incrementally. The restorations were evaluated after one week (baseline), 6 and 18 months, using the FDI and USPHS criteria. Statistical analyses were performed using appropriate tests (α=0.05). ResultsFifteen restorations were lost at 18 months (3 for SE, 2 for ER, 5 for SE+RO and 5 for ER+RO) (p >0.05 between groups). Post-operative sensitivity wasn’t observed in any of the recall periods. Eighty-four restorations were considered to have minor discrepancies in marginal adaptation at the 18-month recall using the FDI criteria (24 for SE, 18 for ER, 22 for SE+RO and 20 for ER+RO; p >0.05 between groups). Nineteen restorations were considered to have minor discrepancies in marginal discoloration at the 18-month recall (10 for SE, 03 for ER, 05 for SE+RO and 01 for ER+RO; p >0.05 between groups). ConclusionThe dentin roughening before application of Tetric N-Bond Universal as self-etch and etch-and-rinse didn’t affect the clinical behavior of composite restorations placed in NCCLs.

Effect of Incorporation of Hydroxyapatite Nanorods on the Rheological Properties, Micro-shear Bond Strength and Degree of Conversion of Two Dental Adhesives

Purpose: The purpose of this study was to evaluate the effect of incorporation ofdifferent concentrations of hydroxyapatite nanorods into two adhesives of two commercialadhesive systems in order to evaluate the effect on rheological properties, microshearbond strength and degree of conversion. Materials and Methods: One hundredtwenty specimens were used in the present study. The specimens were divided into twomain groups (n=60) according to the type of commercial adhesive used AdheSE Bond(I) and Tetric-N Bond Universal (II). Then each group was subdivided into 4 subgroups(n=15) according to the concentration of incorporated HAp nanorods 0( control), 0.2,2, 10wt%HAp nanorods (A, B, C and D, respectively). Each subgroup was furtherdivided into 3 divisions according to the type of test performed (n=5). For rheologicalproperties measurements, a rheometer was used to measure the viscosity and theviscoelastic behavior of the adhesives. For microshear bond strength testing (μSBS),the specimens were tested by using a universal testing machine. The type of failurewas determined by using scanning electron microscope. The degree of conversion wasmeasured using Fourier Transform Infrared (FTIR) spectroscopy. The data were analyzedusing one-way analysis of variance (ANOVA) and Tukey’s post hoc significancedifference tests. Differences were considered significant at p≤0.05. Two ways analysisof variance ANOVA test was used to study the statistical significance of the interactionbetween variables (material and HAp nanorods concentrations). Results: The viscosityof experimental adhesives increased gradually with increasing the concentrations ofHAp nanorods. In μSBS test, the AdheSE containing 0.2 and 2wt.% HAp nanorods producedsignificantly the highest values. Regarding degree of conversion (DC), Tetric-NBond containing 10wt.% HAp nanorods produced significantly the highest value ofDC. Conclusion: Incorporation of HAp nanorods with low concentration (0.2wt %) inAdheSE Bond had a positive impact on the bond strength. However, HAp nanorods asfillers were not suitable to be incorporated in Tetric-N Bond.

Assessment of resin-dentin interfacial morphology of two ethanol-based universal adhesives: A scanning electron microscopy study.

Objective:The objective of this study was to assess the resin-dentin interfacial morphology created by two universal adhesives using scanning electron microscopy (SEM).Materials and Methods:The occlusal surfaces of ten (n = 5) molars were reduced to expose a flat surface of dentin. Two universal adhesives, Scotchbond Universal Adhesive and Tetric N-Bond Universal, were independently applied to air-dried dentin. Light-cured resin-based composite restorative materials were used to incrementally build a composite “buildup.” The specimen was sectioned mesiodistally to expose the resin-dentin interface. The inner surfaces of the specimens were polished. Samples were immersed in hydrochloric acid and then rinsed using distilled water. This was followed by immersion of the samples in 1% sodium hypochlorite solution. Then, samples were thoroughly rinsing with distilled water. Dehydration of samples was performed using ascending concentration of ethyl alcohol. Prepared samples were observed SEM at magnifications ×1500 and x4000.Results:Both universal adhesives could penetrate dentin-forming well-defined resin tags, lateral branches as well as a uniform hybrid layer.Conclusions:Two tested universal adhesives applied in self-etch mode can infiltrate into dentin-producing high-quality interfacial morphology. Similar interfacial morphology may be due to the similarity in composition and application mode.