Introduction: In recent years use of self-ETCH primers has been suggested for fissure sealant therapy due to ease of procedural steps. The aim of this in vitro study was to investigate fissure sealant microleakage in permanent teeth with the ACID-ETCH technique, using one-step and two-step self-ETCH systems.Materials and Methods: A total of 45 sound premolars were selected. Then the occlusal grooves were freshened by the tip of a #1.4 round bur and divided into 3 groups with 15 samples in each group. In the first group after ETCHing by 37% phosphoric ACID, Clinpro sealant was applied on the grooves. In the second and third groups, Clearfil SE Bond two-step self-ETCH and AdheSE One all-in-one one-step self-ETCH bonding systems were used, respectively. The teeth were subjected to thermocycling for 1000 cycles at 5-55oC thermal range. Then the samples were immersed in 0.2% alkaline Fuchsin for 24 hours. After bucco-lingual cross-sectioning, dye penetration under the sealants was evaluated under a stereomicroscope. Data were analyzed by Kruskal-Wallis and Mann–Whitney tests.Results: The results showed significant differences between the three groups (p value<0.001). However, there was no significant difference between Clearfil SE Bond and ACID-ETCH groups in microleakage (p value=0.902). Significantly greater microleakage was observed in the AdheSE One group compared to other groups (p value<0.0001).Conclusion: According to the results of this study, microleakage of fissure sealants with Clearfil SE Bond two-step self-ETCH adhesive was comparable to that of conventional ETCH-and-rinse technique. However, there was more microleakage with AdheSE One one-step self-ETCH adhesive compared to other two groups.

Background: Different clinical steps, weak and ineffective bond are some of the problems of using fissure sealant in primary teeth.Objective: The aim of this study was to compare the effect of a total-ETCHing adhesive (single bond) and a self-ETCHing adhesive (G bond) on the shear bond strength (SBS) of a light curing pit& fissure sealant with primary enamel.Methods: In this experimental study, the crowns of 10 caries-free primary molars were sectioned in a bucco-lingual direction. These 20 specimens were randomly assigned into two groups (single bond & G bond). A light curing pit & fissure sealant (Concise) was bonded to the enamel following application of each bonding system. After 24 hours, the shear bond strength was measured. The data were statistically analyzed using t-test. The failure mode was determined in a stereo microscope at×20.Findings: The shear bond strength of single bond (16.71±0.72) was higher than the G bond (9.62±1.4). There was a significant difference between the shear bond strength in two groups (p<0.05). Most failures were cohesive (80% in single bond & 90% in G bond).Conclusion: According to our data, the self-ETCHing adhesives (G bond) are not reliable alternatives to the total-ETCHing adhesives, if strong bond strength is needed.

Background and Aim: Recently, the use of self- ETCHes primers, due to their ease of manipulation, for fissure sealant therapy is recommended. The aim of this study was to compare the micro leakage of Helioseal F using two methods.Materials and Methods: In this in vitro study, 36 extracted intact human premolar teeth were randomly divided into two groups (n = 18) and were sealed with two methods:1- Conventional ETCHing method.2 - Using Prompt - Lpop ACIDic primer.All specimens were thermocycled for 1000 cycles at 5°C - 55°C, then the teeth were immersed in 2% fuschin solution for 24 hours, sectioned and analyzed by stereomicroscopy. Data were subjected to Mann - Whitney test.Results: There was no statistically significant difference in microleakage of sealants between two methods (P= 0.869). Conclusion: In case of poor patient cooperation along with proper isolation, the use of self - ETCH primers is recommended for fissure sealant therapy.

Introduction: Since bleaching causes changes on dental tissue and affects adhesive bond strengths, it is useful to recognize bonding systems which provide higher bond strengths on the dentin after bleaching. Materials & Methods: Forty eight human sound premolars were selected and sectioned 5mm below the CEJ. In order to do the bleaching process, the access cavity preparation was done and after the excavation of pulp tissue, and placement of the hybrid glass ionomer base at the apex, the teeth were bleached using the 35% hydrogen peroxide for 4 times. The teeth were then embedded in a self-cured acrylic resin and polished to obtain a flat dentin surface. The teeth were assigned into 4 groups according to the adhesive system used (n=12): group 1: Single Bond (SB), group 2: Prime & Bond NT (P&B), group 3: Clearfil SE Bond (CSE) and group 4: Opti Bond (All in one) (OB). The adhesive systems were used according to the manufacturer’s instructions and a cylinder of composite resin Z100 was overlied. The teeth were thermocycled and the shear bond strength tests were performed in a universal testing machine with cross head speed of 1mm/min. Results: CSE had the highest bond strength (15.18 MPa) and SB had the lowest one (8.10 MPa). One Way ANOVA and independent sample t-test showed that the difference in bond strength values among the different types or generations of bondings was statistically significant except for the SB and P&B systems (P<0.05). Conclusion: Within the limitations of this study, it is concluded that two step “self-ETCH” adhesives (CSE) are preferred to use for the teeth undergoing “Non vital tooth bleaching” with 35% hydrogen peroxide than the one step “self-ETCH” adhesives (OB) or two step “ETCH & rinse” adhesives (SB, P&B).

Statement of Problem: Bonded restorations have a number of advantages over traditional, non-adhesive methods. Adhesion reduces the microleakage at the restoration -tooth interface. Prevention of microleakage, or the ingress of oral fluids and bacteria along the cavity wall, reduces the clinical problems such as postoperative sensitivity, marginal staining, and recurrent caries, all of which may jeopardize the clinical longevity of restorative efforts. Purpose: The aim of this study was to evaluate the microleakage in class V composite restoration with total-ETCH and self-ETCH adhesive systems.Materials and Method: In this in -vitro study, 48 standard class V cavities were prepared in the buccal surface of human extracted premolars so that the occlusal margins of the cavities were in the enamel and the gingival margins in the dentin (cementum). The teeth were divided into two groups of 24. In the first group, the cavities were restored with total -ETCH system (Excite) and composite. The teeth in the second group were restored with self-ETCH system (Prompt L –Pop) and the same composite. The teeth were thermocycled 500 times between 5 -55°c and then were covered with nail -polish and adhesive wax except for 1 mm around cavities, and all teeth were immersed into the 2 %methylene blue for 10 hours. The samples were mounted in polyester blocks, sectioned longitudinally at the middle of the cavities, and evaluated for microleakage under a stereomicroscope at 40x magnification. Dye penetration was scored between 0-3. Data were analyzed with Mann Whitney and Wilcoxon tests.Results: In the enamel and dentin margins, microleakage for the total-ETCH group was found to be less than the self-ETCH group (p<0.05). A significant difference in the microleakage mean rank of the enamel and dentin margins was observed (p < 0.05). Microleakage in the enamel margins was less than that in the dentin margins. Conclusion: Total-ETCH adhesive system showed a significant difference on the microleakage of class V composite restorations especially in the enamel margin.

Background and Aims: This ex vivo study was done to evaluate the effect of different adhesive systems on microleakage of class V composite restorations. Materials and Methods: Thirty extracted human third molar teeth were selected and class V cavities were prepared (3×3×1.5 mm) on buccal and lingual surfaces. Then, teeth were divided into 3 groups. Adhesives used in this study were Excite (Ivoclar/Vivadent), AdheSE(Ivoclar/Vivadent) and AdheSE-one Ivoclar (Vivadent/Vivadent). After application of adhesives, cavities were restored with a resine composite (InTen-S A1/ Ivoclar), in 3 increments and cured with QTH light curing unit (700 mW/cm). After 24 hours storage of teeth in 370C water, teeth were thermocycled (500 cycles in 5-550C) and stored in 1% basic fushin for 24 hours. After that, the specimens were rinsed with running water and mounted in a self-cured acryl. Finally, the specimens were sectioned and maximum depth of dye penetration for each restoration was measured using stereomicroscopy. The results were statistically analyzed with Mann-Whitney U test.Results: In comparison between enamel and dentin margins in each group, microleakage in enamel margins were less than that of dentin margins. This difference was statistically significant in Excite and AdheSE-one groups (P=0.001, P=0.043). AdheSE showed the least microleakage in dentin margins; however, there was no significant difference between 3 bonding agents (P=0.14). In enamel margins, there were significant differences between 3 bonding agents (P=0.001). Excite showed the lowest microleakage and AdheSE-one had the highest microleakage.Conclusion: The least enamel microleakage was associated with the total-ETCH and least dentin microleakage was observed in the two-step self-ETCH adhesive system.

Statement of Problems: Enamel preconditioning using phosphoric ACID has been recommended prior to applying self-ETCH adhesives. Meanwhile, there is the possibility for ETCHing of the dentin.Purpose: The aim of this study was to evaluate the shear bond strength (SBS) of two self-ETCH adhesives to the dentin of the primary and permanent teeth in case of phosphoric ACID preconditioning.Methods and Materials: In this experimental study, the buccal surfaces of 48 permanent molars and 48 primary molar teeth were prepared for bonding of two self-ETCH adhesives including Clearfil SE Bond (CSEB) and ACE All Bond SE (ABSE), to the dentin. Each of the permanent and primary teeth was randomly divided into 4 groups (n=12). According to the manufacturers’ instructions, CSEB and ABSE were applied on the dentin or ETCHed dentin of both permanent and primary teeth, then, they were bonded with composite resin. The specimens were stored in water at 37oc for 24 hours and then were thermocycled for 500 cycles. SBS was performed at a crosshead speed of 1.0 mm/min using DARTEC universal machine. The results were statistically analyzed in SPSS 11.5 using Kruskal-Wallis and T-Test.Results: The bond strength of CSEB was significantly higher than ABSE adhesive in both primary and permanent teeth (p=0.001). ACID preconditioning significantly increased the dentin bond strengths of ABSE adhesive in the primary and permanent dentin (p=0.001), and CSEB adhesive in primary dentin.Conclusion: Bond strength of the studied adhesives was significantly different. While ACID phosphoric preconditioning improved the bond strength of the both adhesives in primary teeth, it did not influence the bond strength of the studied two-step self-ETCH adhesive in the permanent dentin.

Statement of problem: Bonding agents are one of the most important materials in adhesive dentistry. Sixth generation bondings have more simple application than fifth generation, but despite this, it has been addressed by some articles that adhesive strength of sixth generation gradually decreases over time. Purpose: The aim of this study was to compare the shear bond strength of a resin composite with application of two bonding agents (fifth and sixth generation) after three months storage in normal saline.Materials and method: This in vitro study was conducted on 40 anterior bovine teeth. After complete removal of enamels, the samples were randomly divided into four groups based on the use of ACID ETCH technique and the type of bonding agents (Excite or Prompt L-pop).After applying Z250 composite resin, the samples were immersed in normal saline for 90 days and then were thermocycled and subjected to shear bond testing with Dartec universal testing machine. Statistical analysis was performed using one-way ANOVA and Tukey's test.Results: In non-ETCHed groups, Prompt L-pop showed significant higher bond strength than Exite, but in ETCHed groups Excite had significantly higher bond strength (p<0.005). There were no significant differences in Prompt L-pop subgroups with or without ETCHing meanwhile in Excite subgroups, significant differences were found.Conclusion: The use of Excite with ACID ETCHing technique provides more reliable bonding than Prompt L-pop to dentin.