Application Of Bonding Agent Research Articles

Technical assessment of shear bond strength at ceramo-alloy interface after various surface treatment combinations and application of metal bonding agent.

Bonding between metal and ceramic is one of the most important aspects of a successful prosthesis. Various methods have been recommended for preparing the metal surface to enhance the bond between metal and ceramic including the use of a metal bonding agent. This study aims to evaluate and compare the shear bond strength of the metal-ceramic (M-C) interface after combinations of various surface treatments including the application of a metal bonding agent. 40 Ni-Cr alloy specimens were made and divided into 4 groups of 10 each based on the combination of surface treatments. Sandblasting, surface grinding, and Oxidation heat treatment (OHT) were performed on specimens from Group 1 (Control). In addition, Group 2 specimens received ultrasonic cleaning, Group 3 steam cleaning, and Group 4 metal bonding agent application. Following surface treatments on all specimens, porcelain build-up was performed, and shear bond strength was tested in a Digital Universal testing machine. The statistical tests used were independent t-test and ANOVA. Results revealed that Group 4 specimens had the highest mean value of shear bond strength of 39.087 MPa while Group 3 specimens showed the least mean shear bond strength of 18.154 MPa with highly statistically significant results (p< 0.001). The surface treatments and application of bonding agent to metal prior to porcelain application resulted in increased shear bond strength of the metal-ceramic interface.

Effectiveness of Different Bonding Agents in Minimally Invasive Cavity Preparations

ABSTRACT Objective: This research is meant to evaluate the effectiveness of different bonding agents in minimally invasive cavity preparations at a tertiary care center. Materials and Methods: A prospective research was conducted involving patients requiring minimally invasive cavity preparations. Patients were randomly assigned to groups based on the bonding agent used. Standardized cavity preparations were performed, and bonding agent application followed manufacturer instructions. Outcome measures included bond strength and marginal adaptation. Data were analyzed using appropriate statistical methods. Results: Bonding Agent A exhibited the highest mean bond strength (25.6 MPa) and superior marginal adaptation (mean score: 4.2) compared to Bonding Agents B and C. These differences were statistically significant (P &lt; 0.001 for bond strength, P &lt; 0.05 for marginal adaptation). Conclusion: Bonding Agent A demonstrated superior performance in achieving durable and esthetically pleasing restorations in minimally invasive cavity preparations. These findings underscore the importance of selecting appropriate bonding agents for conservative dental treatments to optimize treatment outcomes and patient satisfaction.

Evaluation of Shear Bond Strengths of 3D Printed Materials for Permanent Restorations with Different Surface Treatments.

The development of high-filled 3D printing resin necessitates a bonding protocol for dental indirect restorations to achieve optimal bond strength after cementation. This study evaluates shear bond strengths of high-filler 3D printed materials for permanent restorations with various surface treatments. Rodin Sculpture 1.0 (50% lithium disilicate fillers) and 2.0 Ceramic Nanohybrid (>60% zirconia and lithium disilicate fillers) were tested, with Aelite All-Purpose Body composite resin as control. Samples were prepared, post-cured, and sandblasted with alumina (25 µm). Surface roughness was analyzed using an optical profilometer. Two bonding protocols were compared. First, groups were treated with lithium disilicate silane (Porcelain Primer) or zirconia primer (Z-Prime Plus) or left untreated without a bonding agent. Beam-shaped resin cement (DuoLink Universal) specimens were bonded and stored in a 37 °C water bath. Second, additional sets of materials were coated with a bonding agent (All-Bond Universal), either followed by silane application or left untreated. These sets were then similarly stored alongside resin cement specimens. Shear bond tests were performed after 24 h. SEM images were taken after debonding. One-Way ANOVA and post hoc Duncan were performed for the statistical analysis. Rodin 1.0 exhibited increased adhesive failure with silane or zirconia primer coating, but significantly improved bond strengths with bonding agent application. Rodin 2.0 showed consistent bond strengths regardless of bonding agent application, but cohesive failure rates increased with bonding agent and filler coating. In all groups, except for Rodin 1.0 without bonding agent, silane coating increased cohesive failure rate. In conclusion, optimal shear bond strength for high-filler 3D printing materials can be achieved with silane coating and bonding agent application.

Comparison of the Shear Bond Strength of Compomer Bonding on Different Enamel Surface Preparations

Objectives: To compare the effects of etching time and bonding agent application on the shear bond strength of compomer bonding in orthodontic bite raising. Methods: Seventy-five sectioned crown of maxillary premolar teeth were embedded in acrylic rings. The samples were divided into 5 groups according to enamel surface preparation before applying Ultra Band-Lok® (Reliance Orthodontic Products). Group 1: without surface preparation, Group 2: etched with 37% phosphoric acid (Kerr Gel Etchant, Kerr®) for 15 seconds, Group 3: etched with 37% phosphoric acid for 15 seconds, then apply bonding (OptiBond™ FL), Group 4: etched with 37% phosphoric acid for 30 seconds and Group 5: etched with 37% phosphoric acid for 30 seconds, then apply bonding. All samples were put through the thermocycling procedure and then shear bond strength was tested using the Universal Testing Machine. The mean and standard deviation of shear bond strength were statistically analyzed with two-way ANOVA and the enamel surface was observed by scanning electron microscope at 10,000x magnifications. Result: In Group 1, all Ultra Band-Lok® dislodged from the enamel surface during the thermocycling process. Consequently, shear bond strength testing could not be conducted for Group 1. The mean shear bond strength of Groups 2-5 were 19.80±7.06, 18.97±4.60, 18.04±5.09 and 16.80±5.47 MPa respectively. The mean shear bond strength of each group was not statistically significant difference (p=0.887). Conclusions: Varying enamel etching times (15 and 30 seconds) did not affect the compomer shear bond strength. Furthermore, the application of a bonding agent during tooth surface preparation did not significantly improve the bond strength between the compomer and the tooth surface.

Preventive Effects of Laser Irradiation and Dentin Bonding Agent Application on Tooth Discoloration Induced by Mineral Trioxide Aggregate

The aim of the present study was to evaluate the effect of the pre-application of dentin bonding agent and laser application on the prevention of tooth discoloration caused by (MTA) in the presence of blood. Fifty extracted human anterior teeth were prepared by standardizing root lengths to 10 mm and shaping root canals. Specimens were divided into five groups (n = 10) based on the treatment applied to the pulp chamber dentin wall: Group 1/no surface treatment; Group 2/Optibond FL; Group 3/Clearfil SE; Group 4/Optibond Universal adhesive application; Group 5/Nd:YAG laser application. Root canals were filled with fresh human blood below the cemento-enamel junction (CEJ), followed by ProRoot MTA, and collagen barrier placement. Color changes were monitored using a spectrophotometer at 0, 7, 30, 90, and 180 days post MTA placement. Color differences (∆E) were calculated and analyzed using two-factor mixed-design ANOVA with Sidak adjustment at p = 0.05. The degree of coloration increased with time within each group (p &lt; 0.05). No significant differences were observed between Optibond FL and Optibond Universal within each time interval, or between Clearfill SE Bond and the control group (p &gt; 0.05). When compared to the control group, the Nd YAG group exhibited the least degree of discoloration in all time intervals (p &lt; 0.05). Although the Nd:YAG laser had promising results, none of the methods can guarantee a 100% prevention of discoloration resulting from tooth discoloration caused by MTA-blood contact.

Complimentary Staining of Caries Detector Dyes in Primary Teeth with or without the Application of a Dentine Bonding Agent

Background: Caries detector dyes are introduced to aid in identifying infected dentine. Many researchers claim that they are not specific in identifying infected dentine since dyes also stains sound tooth surfaces. The use of a dentine bonding agent could help in avoiding the penetration of caries detector dyes to some extent in less mineralized primary teeth. This study assesses caries detector dyes penetration in primary teeth with or without dentine bonding agent application. Methodology: Ninety primary extracted carious teeth were considered for the study. Teeth were divided in to two groups (45 teeth each group): group I with dye application without dentine bonding agent and group II with dye application after dentine bonding agent; in both groups three different types of dyes were used. All cavity walls and surfaces of samples in group 1 were stained with caries detector dyes for 10 s, subsequently washed with water for another 10 s and finally air-dried. A similar procedure was carried for teeth in group II after the application of a bonding agent on visibly sound tooth surfaces without the use of an etchant. Results: A statistically significant difference between two groups for staining of different tooth surfaces was noted. A Kruskal–Wallis one-way ANOVA revealed a statistically significant difference in stain removal among the different groups either by distilled water or sodium hypochlorite were observed. Conclusion: A dentine bonding agent can help in preventing caries detector dye penetration in noncarious tooth surfaces of deciduous teeth.

Effect of nonthermal atmospheric plasma on bond strength of composite resin using total-etch and self-etch adhesive systems.

The aim of this study was to assess the impact of nonthermal atmospheric plasma (NTAP) on the bond strength of composite resin following plasma application at different steps of dentin bonding in total-etch and self-etch adhesive systems. Ninety extracted third molars were taken, and the occlusal surfaces were removed until the exposure of the dentin. Samples were distributed into two main groups: Group T: total-etch adhesive system and Group S: self-etch adhesive system. Groups are further subdivided (n = 10) based on plasma application at different steps of dentin bonding. T1: surface etching with 37% phosphoric acid and bonding agent application. T2: plasma application and bonding agent application. T3: plasma application, etching, and bonding agent application. T4: etching, plasma application, and bonding agent application. T5: etching, plasma application, bonding agent application, and again plasma application. S1: self-etch bonding agent application. S2: plasma application and bonding agent application. S3: Bonding agent application and plasma application. S4: plasma application, bonding agent application, and again plasma application. For all the samples, composite resin buildup was done, and shear bond strength (SBS) was measured. The contact angle was measured at different steps of dental adhesive systems. Two-way analysis of variance and the post hoc Tukey's test were used for analysis, regarding P < 0.05 as statistically significant. Among all groups of total-etch and self-etch adhesives, Group T4 (48.81 Mpa) and Group S2 (36.59 Mpa), respectively, have demonstrated significantly greater bond strength values than the corresponding control groups. NTAP enhanced the composite resin's SBS when plasma treatment was done before bonding agent application and significantly reduced the contact angles of the distilled water.

Clinical Evaluation of the Retention of Self-adhering Flowable Composite as Fissure Sealant in 6-9-year-old Children: A Randomized Controlled Trial.

AimTo evaluate the retention rate of self-adhering flowable composite as fissure sealant in comparison with the unfilled resin sealant on first permanent molars of 6–9-year-old children.Materials and methodsA 2-arm, split-mouth randomized controlled trial included 100 children of age 6–9 years with completely erupted mandibular first permanent molars. A total of 200 teeth were randomly divided into two groups, group I: self-adhering flowable composite; group II: unfilled resin sealant. Sealants were placed on the mandibular first permanent molars and the children were recalled at 6, 12, and 18 months intervals to evaluate the retention rate. Chi-square test was used to analyze the data.ResultsSelf-adhering flowable composite has shown a complete retention rate of 67%, 47%, and 46% at 6, 12, and 18-month intervals, respectively, whereas unfilled resin sealant has shown 41%, 8%, and 5% retention rate at 6, 12, and 18-month intervals, respectively. The difference in the complete sealant retention rates between the groups is found to be statistically highly significant at all the follow-up intervals (p = 0.0004, 0.0001, and 0.0001 at 6, 12, and 18-month intervals, respectively). In both groups, maximum sealant loss occurred between 6 and 12-month intervals. Retention rates were higher at 6 months intervals which were significantly reduced over 18 months intervals.ConclusionSelf-adhering flowable composite has shown a higher retention rate compared to unfilled resin sealant at all the time intervals. The retention rate of both materials decreased with time. However, the loss of sealant was more with unfilled resin sealant.Clinical significanceIn pediatric dental practice, the elimination of a step in restorative dentistry protocol makes a big difference as time is a critical factor in obtaining children's cooperation. The use of self-adhering materials eliminates the step of bonding agent application, which simplifies the restorative protocol and makes the clinical practice effective. Therefore, these self-adhering flowable composite resin materials can be considered fissure sealants in routine clinical practice.How to cite this articleBhuvaneswari P, Vinay C, Uloopi KS, et al. Clinical Evaluation of the Retention of Self-adhering Flowable Composite as Fissure Sealant in 6–9-year-old Children: A Randomized Controlled Trial. Int J Clin Pediatr Dent 2022;15(3):322-326.

Influence of bonding agent application method on the dentin bond durability of a two-step adhesive utilizing a universal-adhesive-derived primer.

This study investigated the effect of the bonding agent application method on the dentin bond durability of a two-step adhesive utilizing a universal-adhesive-derived primer. The bonding durability of a universal adhesive was compared with those of two conventional two-step adhesives by shear bond strength testing after thermal cycling. The primer was applied (with or without phosphoric acid pre-etching), and the specimens were divided into three groups based on the bonding agent application method used as follows: (i) strong air-flow application, (ii) gentle air-flow application, and (iii) gentle air-flow + second bonding application. The shear bond strength was determined after thermal cycling. All the factors (bonding agent application method, adhesive system, and storage condition) significantly influenced the dentin shear bond strength both with and without phosphoric acid pre-etching. The specimens exposed to gentle air-flow showed a higher shear bond strength than did those exposed to strong air-flow and gentle air-flow + second bonding. The bond durability of the tested adhesive systems was influenced by the bonding agent application method, and this trend was material dependent. The G2-Bond Universal exhibited the same or greater dentin bond durability to the other two-step adhesive systems.

EFFECT OF ADHESIVE ON MICRO SHEAR BOND STRENGTH OF A NEW BIOACTIVE, RESTORATIVE MATERIAL ON NORMAL AND CARIES-AFFECTED DENTINE

ABSTRACT Objectives: Activa BioActive-Restorative is defined as a self-adhesive dual-cured resin-modified glass ionomer. The suggested application method includes only conditioning to the dentine with acid and keeps bonding optional. This study aims to evaluate the micro shear bond strength in the presence and absence of the bonding agent application after acid conditioning for different dentin surfaces. Materials and Methods: 30 posterior molars having occlusal caries were used. The flat dentin surfaces involving normal dentin (ND) and caries affected dentin (CAD) were prepared and randomly divided into three groups: Activa BioActive-Restorative (Pulpdent, USA) with only 10 seconds of acid application (Act), Activa with acid and bonding application (Optibond All in one, USA) (Act B), GC G-aenial Universal posterior composite with acid and bonding application (GC, Japan). A total of 6 groups were formed, as each group had normal and caries-affected dentin surfaces. Universal test machines were used to calculate micro shear bond strength at a crosshead speed of 0.5 mm/min, and failure modes were determined by stereomicroscope. Results: There was no statistically significant difference between test values of each group neither for ND (p:0,065; p&amp;gt;0,05) nor for CAD (p:0,110; p&amp;gt;0,05). There is no statistically significant difference between μ-SBS values of the ND and CAD subgroup for any of the groups (Act p:0,933; Act B p:0,684; GC p:0,863; p&amp;gt;0,05). Adhesive failure dominated the other failure modes. Conclusions: There is no difference between adherence of the material to ND and CAD. Acid application is sufficient for adequate binding. However, an optional bond application can be recommended, especially for dentin cavities. Keywords: Micro shear bond strength, bioactivity, adhesion

Comparative evaluation of adhesion of glass fiber post to the root dentin after surface treatment of post and using universal bonding agent: An in vitro study.

The purpose of the study is the evaluation and comparison of surface roughness and bond strength of glass fiber post (GFP) after different types of surface treatment and the application of a universal bonding agent. Forty GFPs were divided into four groups based on surface treatment: Group I, silane coupling agent application for 60 s; Group II, air abrasion with 30 μm silicon dioxide powder particles in 2.5 bar pressure from 2 cm distance for 10 s, followed by silane coupling agent application; Group III, 9% hydrofluoric acid application for 10 s, rinsed and air-dried, followed by silane coupling agent application; and Group IV, silane coupling agent application, followed by universal bonding agent application. Surface roughness evaluation is done by a profilometer. All posts were cemented in the root of the maxillary central incisor with resin cement. After that, root was placed in an acrylic mold, and the external end part of the post was mounted on another acrylic mold. Pull-out bond strength was measured by a universal testing machine. Highest surface roughness and bond strength values were found in Group II. Pretreatment of GFP increases the surface roughness of post as well as bond strength of post to root dentin. There is a correlation between surface roughness and bond strength. However, the use of only universal bonding agent also showed comparable pull-out bond strength of GFP, which means only use of universal bonding agent also a new alternative as pretreatment of GFP and helps in increase in bond strength.

Long-term effect of curcuminoid treatment on resin-to-dentin bond strength.

Endogenous dentin proteases contribute to the degradation of collagen fibrils in the hybrid layer. Recently, inhibition of host-derived proteases by curcuminoids has shown promising results. The aim of this study was to evaluate the effect of curcuminoid treatment on the microtensile bond strength (μTBS) after 24 h or 12 months of storage. Fifty-four extracted sound human molars were flattened to mid-coronal dentin and divided into nine groups. After phosphoric acid-etching for 15 s, the dentin was experimentally treated for 60 s using 100μM or 200μM of curcumin, diflourobenzocurcumin, or demethoxycurcumin dissolved in 1% and 2% dimethyl sulfoxide (DMSO)/water solutions. Untreated and DMSO-treated groups served as controls. After bonding agent application, each tooth was restored with dental composite. The molars were sectioned into 0.9×0.9×6 mm beams. The μTBS testing was performed after 24 h and 12 months of storage in artificial saliva. Data were analyzed using regression analyses. Failure patterns were evaluated using scanning electron microscopy. Dentin treatment with curcuminoids did not adversely affect 24-h μTBS compared to controls. After 12 months, the μTBS of curcuminoid groups was statistically significantly higher than the controls. This study indicates the feasibility of using curcuminoids as protease inhibitors.

Adhesive systems applied to dentin substrate under electric current: systematic review.

ObjectivesThe purpose of this systematic review was to collect and discuss the technique of adhesive systems application on dentin substrate under electric current.Materials and MethodsThe first search strategy was based on data available at PubMed, LILACS, Scielo, Scopus, and Cochrane Library, using a combination of descriptors such as “dentin bond agents OR adhesive system AND electric current OR electrobond” or “dentin bonding agents OR dentin bonding agent application OR adhesive system AND electric current OR electrobond”, with no limit regarding the publication year. The second search strategy was based on the articles' references found previously. An additional search strategy was applied that concerned the proposed theme in the SBU-UNICAMP (Unicamp's Library System Institutional Repository).ResultsTwelve studies published between 2006 and 2020 were found. The analyses of the selected studies showed that the use of electric current during adhesive systems application on dentin, whether conventional or self-conditioning, increases resinous monomer infiltration in the dentin substrate, which improves the hybridization processes and the bond strength of the restorative material to dentin.ConclusionsDespite the favorable results related to the use of this technique, there is still no specific protocol for the application of adhesive systems under electric current.

Comparison of marginal adaptation of Class II cavities restored with bulk-fill and conventional composite resins using different universal bonding agent application strategies

This in vitro study was conducted to compare the effect of universal bonding application strategy (i.e., self-etch and etch-and-rinse) on marginal adaptation of bulk-fill and conventional composite resins in Class II restorations. In this in vitro study sixty sound premolars extracted for orthodontic reasons were selected. The samples were allocated to four groups based on the universal bonding application strategy (self-etch and etch and rinse) and type of composite (bulk-fill and conventional). In each group, boxes were prepared with a depth of 4 mm on the mesial surfaces. Finally, the marginal adaptation of the samples was evaluated under a stereomicroscope. Two-way ANOVA was used to compare the marginal adaptation data in the study. Statistical significance was set at P < 0.05. Considering the type of universal bonding application strategy, there was a statistically significant difference in marginal adaptation. Etch-and-rinse strategy showed better marginal adaptation compared to self-etch strategy (P < 0.001). However, there was no statistically significant difference in marginal adaptation between the two composite resins (P = 0.829). Furthermore, the interaction between the two factors (type of universal bonding application strategy and type of composite resin) was not statistically significant (P = 0.629). Etch-and-rinse bonding application strategy in both the bulk-fill and conventional composite resins exhibited better marginal adaptation compared to self-etch bonding application strategy. However, the difference of marginal adaptation between the two types of composite resins (bulk and conventional) was not significant.

Surface treatments of a glass-fiber reinforced composite: Effect on the adhesion to a composite resin

PurposeTo compare the effect of different surface treatments (pre-treatments and bonding agents) on the bond strength between glass-fiber post and composite resin, and the topographic alterations of the treated post surface. MethodsThirty-six glass-fiber blocks (12mm×10mm×8mm) were specifically manufactured for this study and randomly assigned into 12 groups considering two factors: ‘pre-treatments’ (–cleaning with 70% alcohol; air-abrasion with silica-coated aluminum oxide particles; 35% hydrogen peroxide) and type of ‘bonding agent’ (no bonding agent; application of Monobond Plus; RelyX Ceramic Primer; Single Bond Universal). After that, 6 cylindrical templates (1mm high×1mm Ø) were fixed on each block, filled with composite resin (n=18) and light-cured. Specimens were stored under 37°C for 24h and microshear tests (wire loop Ø=0.2mm) were performed. Topographic, roughness and failure analyses were also performed. ResultsDifferent surface pre-treatments led to different topographic and roughness alterations; a higher surface alteration was noted after silica particles air-abrasion, while a slight surface alteration in the hydrogen peroxide group and a smooth pattern were observed in the cleaning group. The factors ‘pre-treatments’ (p<0.05), ‘bonding agent’ (p<0.05) and their interaction (p<0.05) influenced the bond strength. Silica coating, apart from bonding agent application, or Single Bond Universal application without pre-treatment promoted the highest bond values. The main failure type was adhesive at the resin-post interface. ConclusionsIn terms of pre-treatments, silica coating promotes the best bonding performance, but pre-treatments can be dispensable when applying Single Bond Universal.

Concepts and techniques to improve resin/resin bonding. Literature Review.

The availability of new scientific information about the etiology, diagnosis and treatment of carious lesions and the introduction of reliable adhesive restorative materials substantially reduced the need of extensive tooth preparations. In order to achieve a successful procedure, an adequate bonding interface between old and new composite is required. The aim of this article is to review the concepts and techniques described in the literature for the improvement of resin-resin bonding. Bonding to dentin has been quite difficult to achieve. The difficulties are that dentin’s histological structure and chemical composition are very different from those of the enamel. Bonding to dentin requires, besides acid conditioning and the adhesive required for enamel, a primer or dentin bonding agent, which is a hydrophilic, able to penetrate by infiltrating the microscopic spaces of the collagen mesh. The repairing of faulty restorations is a treatment option that has proven to be quite effective and safe, since it presents excellent results over time. For this purpose, different methods for surface treatment have been developed, which has a great effect on the resistance of the reparation bonding. In order to achieve successful bonding between both resins, the following steps are recommended, including: surface roughening, acid etching, silane application, and bonding agent application.

Influence of surface airborne-particle abrasion and bonding agent application on porcelain bonding to titanium dental alloys fabricated by milling and by selective laser melting

Statement of problemComputer-aided design and computer-aided manufacturing (CAD-CAM) technologies have provided alternatives to lost-wax casting for the fabrication of titanium frameworks in metal-ceramic fixed dental prostheses (FDPs). The findings on varying metal surface characteristics resulting from application of different fabrication technologies indicate a need to reevaluate the traditional titanium surface conditioning protocols. PurposeThe purpose of this in vitro study was to investigate the effects of surface airborne-particle abrasion (APA) and bonding agent application on the porcelain bond to titanium dental alloys fabricated by subtractive computer numerical controlled (CNC) milling and by additive selective laser melting (SLM) methods. Material and methodsEight groups of Ti-6Al-4V substrates (n=11) were fabricated—half of them by CNC milling and half by SLM. The groups represented a fully crossed experimental protocol of APA with 110-μm Al2O3 particles under a pressure of 0.2 MPa (intact—controls or abraded) and bonding agent application (with or without bonding agent) for the CNC milled and SLM titanium substrates. Ultra-low fusing dental porcelain was applied to the differently prepared titanium substrates, and the titanium-ceramic bond strength was determined by a 3-point bend test according to the International Organization for Standardization (ISO) standard 9693-1:2012. Average profile roughness (Ra) values were obtained for intact and APA titanium substrates fabricated by CNC milling and by SLM. Representative titanium-ceramic interfaces were analyzed by using a field emission scanning electron microscope (FE-SEM) and energy dispersive spectroscopy (EDS). Titanium-ceramic bond strength data were analyzed statistically by 3-way ANOVA and the Tukey HSD test. Ra data were analyzed by 2-way ANOVA, followed by regression analyses (α=.05). ResultsThe method applied for the digital fabrication of titanium (either subtractive CNC milling or additive SLM) did not affect the titanium-ceramic bond (P=.247). APA (P<.001), as well as the application of a bonding agent (P<.001), increased the titanium-ceramic bond strength. When these 2 procedures were combined, the porcelain bond strength to CNC milled titanium was 37.3 ±4.1 MPa and that to SLM titanium was 36.7 ±4.9 MPa. APA increased the surface roughness of CNC milled titanium (P=.002) but decreased the roughness of the SLM substrates (P<.001). ConclusionsA protocol comprising APA and application of a bonding agent ensures the highest porcelain bond strength to both CNC milled and SLM titanium, with the obtained values being well above the minimal value for metal-ceramic systems as specified by ISO 9693-1:2012.

Interfacial microscopic examination and chemical analysis of resin-dentin interface of self-adhering flowable resin composite.

Background: The newly introduced self-adhering flowable resin-composites decrease the required time for application by incorporation of an acidic adhesive monomer, thus reducing the number of steps, but its bonding is still uncertain. The aim of this study was to evaluate the interfacial microscopic examination and chemical analysis at the resin-dentin interface of a self-adhering flowable resin composite (Vertise™Flow Self-Adhering Flowable Composite, Kerr Dental, USA) versus a total-etch (Te-Econom Plus) resin composite, using an etching agent (Eco-Etch gel) and bonding agent (Single Bond Universal). Methods: Sixteen freshly extracted sound human posterior teeth were used. The teeth were randomly divided into two groups: 8 specimens per type of composite. Standard-shaped class V cavities were prepared on the buccal surface. One group was restored by Te-Econom Plus resin composite by total-etch technique using Eco-Etch gel, which was applied to dentine for 15 seconds, followed by rinsing, drying and bonding agent application (Single Bond Universal). The other group restored directly with self-adhering resin composite (Vertise-Flow) without application of etch or bond. Curing was done for 20 seconds using a light emitting diode light curing unit. Evaluation of the resin-dentin interface was done microscopically by examination of marginal gap distance in μm using scanning electron microscope (SEM), and chemical analysis of silver particles was observed using SEM with energy-dispersive X-ray spectrometry after 24 hours of specimen storage in ammoniacal silver nitrate. Results: Regarding marginal gap distance (µm) and silver atomic % mean values, teeth restored with self-adhering resin composite (Vertise-Flow) showed significantly higher mean values than the multi-step etch and rinse resin composite group (5.2 vs 0; 12.2 vs 8.2, respectively). Conclusions: Resin-dentin bonding using total-etch resin composite technique was more effective than self-adhering flowable resin composite (Vertise-Flow) regarding marginal gap formation and penetration of silver particles. Further studies for bond strength could be performed.

Combined Effect of Enamel Deproteinization and Intermediate Bonding in the Retention of Pit and Fissure Sealants in Children: A Randomized Clinical Trial.

This manuscript shows if enamel deproteinization along with an intermediate layer of bonding enhances the retention of pit and fissure sealants.. Two hundred six mandibular first permanent molars were allocated to Group I (n=103) and Group II (n=103). Group I underwent deproteinization, acid etching, bonding agent application and pit & fissure sealant placement while Group II treated with acid etching followed by pit & fissure sealant application only. Clinical analysis of all the teeth in the two groups was performed at 1, 3, 6, 9 and 12 months respectively. Pearson's chi - square test was utilized to evaluate the success of both treatment procedures (p<0.05). At 12 months follow up the differences between the groups pertaining to Marginal integrity, Marginal discoloration and Anatomical form were statistically significant suggesting enhanced retention in Group I. Enamel deproteinization along with the use of intermediate bonding layer significantly enhances the retention of pit and fissure sealants in terms of enhanced marginal integrity, decreased marginal discoloration and preserving the anatomical form.

Marginal microleakage of composite resin restorations with surface sealant and bonding agent application after finishing and polishing

Microleakage at the marginal area of composite resin restorations can lead to discoloration and secondary caries. Performing rebonding after finishing and polishing can reduce microleakage of composite resin restorations. This study aimed to analyze the marginal microleakage of composite resin restorations after rebonding with a surface sealant and a bonding agent. Cavity preparation was performed on the buccal side of 60 human premolar teeth (3 mm in diameter and 2 mm in depth). Samples were randomly divided into two groups for rebonding with the different materials. Group 1 samples were rebonded with the surface sealant, whereas group 2 samples were rebounded with the bonding agent. Microleakage was measured using 1% methylene blue after thermocycling. Lesser microleakage was seen in group 1 than in group 2, with a statistically significant difference between the two groups (p < 0.05). Rebonding with a surface sealant can reduce marginal microleakage of composite resin restorations better than rebonding with a bonding agent.