Optibond Solo Research Articles

Bond strength of composite resin to white mineral trioxide aggregate: Effect of different surface treatments.

Background:The main aim of restorative dentistry is to restore and preserve dental health with the use of appropriate restorative modalities to protect the pulp and restore its function. This study compared the effect of different surface treatments of mineral trioxide aggregate (MTA) on the bond strength of composite resin to MTA.Materials and Methods:Forty cylindrical acrylic blocks with a hole were prepared and filled by ProRoot MTA. The samples were assigned to four groups: Group 1 – no surface treatment; Group 2 – phosphoric acid etching; Group 3 – sandblasting; and Group 4 – hydrofluoric acid (HF) etching, rinsing, and silane application. OptiBond Solo Plus adhesive was utilized in all the groups. Then, composite resin cylinders were bonded to sample surfaces. The samples were thermocycled and tested for microshear bond strength using a universal testing machine at a crosshead speed of 1 mm/min. Data were analyzed with Kruskal–Wallis and Mann–Whitney tests. Scanning electron microscopy images were prepared for each study group after surface treatments.Results:Means and standard deviations of bond strength values in study groups 1–4 were 14.83 ± 7.76, 21.85 ±7.99, 6.48 ± 3.89, and 26.01 ± 11.09 Mpa, respectively.Conclusions:Within the limitations of this study, phosphoric acid etching or HF etching plus silanization was preferred to surface treatment of MTA before composite resin bonding.

Effect of Proteolytic Agents on Microleakage of Etch and Rinse Adhesive Systems

Objective: this study aimed to assess the effect of treatment of phosphoric acid etched dentin surface with 5% bromelain enzyme and Nd:YAG laser prior to the use of etch and rinse adhesive systems on microleakage margins of class V composite restorations. Materials and Methods: sixty sound premolar teeth were selected. Standard class V cavities were prepared in the buccal and lingual surfaces of each teeth. Preparation in that way 1 mm of the cavity was above and 1 mm of it was below the cementoenamel junction. The teeth were then randomly divided into three groups including 20 teeth(40cavities in each gorup). Two ethanol base etch and rinse system (Adper Single Bond and OptiBond Solo) was applied in each group. In the control group, cavities were etched with 37% phosphoric acid. Adper Single Bond was applied to 20 and OptiBond Solo was applied to the remaining 20 cavities and they were restored with Z250 composite (n=40). The same procedures were performed in bromelain and Nd:YAG laser groups with the difference that prior to the application of adhesive, aqueous 5% bromelain was applied in bromelain group while Nd:YAG laser was irradiated in laser group. All teeth were thermocycled and their apices were sealed with sticky wax. The tooth surfaces were coated with nail varnish except for 1 mm around the restoration margins, and the teeth were then immersed in fuchsine and sectioned by a diamond disc into mesial and distal halves. Marginal microleakage at both sides was determined and scored under a stereomicroscope at x40 magnification. Then data were analyzed using the Kruskal Wallis and Mann Whitney tests (α=0.05). Results: according the result of Mann Whitney test, Cervical margins showed significantly higher microleakage than the occlusal margins (P=0.000) but no significant difference was noted in microleakage of occlusal (P=0.362) or gingival (P=0.147) margins among the three groups by Kruskal Wallis test. Conclusion: in conclusion, application of proteolytic agents(5% bromelain solution and Nd:YAG laser) on acid-etched dentin surface prior to the application of adhesive has no significant effect on marginal microleakage of class V composite restorations.

Bond strength of etch-and-rinse and self-etch adhesive systems to enamel and dentin irradiated with a novel CO2 9.3μm short-pulsed laser for dental restorative procedures.

The objective of this study was to evaluate the influence of CO2 9.3μm short-pulsed laser irradiation on the shear bond strength of composite resin to enamel and dentin. Two hundred enamel and 210 dentin samples were irradiated with a 9.3µm carbon dioxide laser (Solea, Convergent Dental, Inc., Natick, MA) with energies which either enhanced caries resistance or were effective for ablation. OptiBond Solo Plus [OptiBondTE] (Kerr Corporation, Orange, CA) and Peak Universal Bond light-cured adhesive [PeakTE] (Ultradent Products, South Jordan, UT) were used. In addition, Scotchbond Universal [ScotchbondSE] (3M ESPE, St. Paul, MN) and Peak SE self-etching primer with Peak Universal Bond light-cured adhesive [PeakSE] (Ultradent Products) were tested. Clearfil APX (Kuraray, New York, NY) was bonded to the samples. After 24h, a single plane shear bond test was performed. Using the caries preventive setting on enamel resulted in increased shear bond strength for all bonding agents except for self-etch PeakSE. The highest overall bond strength was seen with PeakTE (41.29±6.04MPa). Etch-and-rinse systems achieved higher bond strength values to ablated enamel than the self-etch systems did. PeakTE showed the highest shear bond strength with 35.22±4.40MPa. OptiBondTE reached 93.8% of its control value. The self-etch system PeakSE presented significantly lower bond strength. The shear bond strength to dentin ranged between 19.15±3.49MPa for OptiBondTE and 43.94±6.47MPa for PeakSE. Etch-and-rinse systems had consistently higher bond strength to CO2 9.3µm laser-ablated enamel. Using the maximum recommended energy for dentin ablation, the self-etch system PeakSE reached the highest bond strength (43.9±6.5MPa).

Biocompatibility and bond degradation of poly-acrylic acid coated copper iodide-adhesives

ObjectiveTo investigate the effect of poly-acrylic acid (PAA) copper iodide (CuI) adhesives on bond degradation, tensile strength, and biocompatibility. MethodsPAA-CuI particles were incorporated into Optibond XTR, Optibond Solo and XP Bond in 0.1 and 0.5mg/ml. Clearfil SE Protect, an MDPB-containing adhesive, was used as control. The adhesives were applied to human dentin, polymerized and restored with composite in 2mm-increments. Resin–dentin beams (0.9±0.1mm2) were evaluated for micro-tensile bond strength after 24h, 6 months and 1year. Hourglass specimens (10×2×1mm) were evaluated for ultimate tensile strength (UTS). Cell metabolic function of human gingival fibroblast cells exposed to adhesive discs (8×1mm) was assessed with MTT assay. Copper release from adhesive discs (5×1mm) was evaluated with UV–vis spectrophotometer after immersion in 0.9% NaCl for 1, 3, 5, 7, 10, 14, 21 and 30 days. SEM, EDX and XRF were conducted for microstructure characterization. ResultsXTR and Solo did not show degradation when modified with PAA-CuI regardless of the concentration. The UTS for adhesives containing PAA-CuI remained unaltered relative to the controls. The percent viable cells were reduced for Solo 0.5mg/ml and XP 0.1 or 0.5mg/ml PAA-CuI. XP demonstrated the highest ion release. For all groups, the highest release was observed at days 1 and 14. SignificancePAA-CuI particles prevented the bond degradation of XTR and Solo after 1year without an effect on the UTS for any adhesive. Cell viability was affected for some adhesives. A similar pattern of copper release was demonstrated for all adhesives.

Comparative bonding ability to dentin of a universal adhesive system and monomer conversion as functions of extended light curing times and storage.

The purpose of this in vitro study was to evaluate the bonding ability and monomer conversion of a universal adhesive system applied to dentin as functions of different curing times and storage. The results were compared among a variety of commercial adhesives. Flat superficial dentin surfaces were exposed on human molars and assigned into one of the following adhesives (n = 15): total-etch Adper Single Bond 2 (SB) and Optibond Solo Plus (OS), self-etch Optibond All in One (OA) and Clearfil SE Bond (CSE), and Scotchbond Universal Adhesive in self-etch mode (SU). The adhesives were applied following the manufacturers' instructions and cured for 10, 20, or 40s. Specimens were processed for the microtensile bond strength (µTBS) test in accordance with the non-trimming technique and tested after 24h and 2 years. The fractured specimens were classified under scanning electron microscopy (SEM). Infrared (IR) spectra were obtained and monomer conversion (%) was calculated by comparing the aliphatic-to-aromatic IR absorption peak ratio before and after polymerization (n=5). Data were analyzed by 2-way ANOVA/Tukey's tests (α = 0.05). At 24-h evaluation, OA and CSE presented similar bond strength means irrespective of the curing time, whereas SB and SU exhibited significantly higher means when cured for 40s as did OS when cured for 20 or 40s (p < 0.05). At 2-year evaluation, only OA exhibited significantly higher bond strength when cured for 20 and 40s (p < 0.05). When the evaluation times were compared, OA also exhibited the same bonding ability when cured for longer periods of time (20 and 40s). All of the adhesives tested exhibited significantly lower monomer conversion when photoactivated according to the manufacturers' instructions (10s). Higher monomer conversions obtained with longer light exposure allow only higher immediate bond strength for most of the adhesives tested. After 2-year storage, only the self-etching adhesive Optibond All-In-One exhibited the same bonding ability when cured for longer periods of time.

Antibacterial Activity of Commercial Dentine Bonding Systems against E. faecalis–Flow Cytometry Study

Literature presents inconsistent results on the antibacterial activity of dentine bonding systems (DBS). Antibacterial activity of adhesive systems depends on several factors, including composition and acidity. Flow cytometry is a novel detection method to measure multiple characteristics of a single cell: total cell number, structural (size, shape), and functional parameters (viability, cell cycle). The LIVE/DEAD® BacLight™ bacterial viability assay was used to evaluate an antibacterial activity of DBS by assessing physical membrane disruption of bacteria mediated by DBS. Ten commercial DBSs: four total-etching (TE), four self-etching (SE) and two selective enamel etching (SEE) were tested. Both total-etching DBS ExciTE F and OptiBond Solo Plus showed comparatively low antibacterial activity against E. faecalis. The lowest activity of all tested TE systems showed Te-Econom Bond. Among SE DBS, G-ænial Bond (92.24% dead cells) followed by Clearfil S3 Bond Plus (88.02%) and Panavia F 2.0 ED Primer II (86.67%) showed the highest antibacterial activity against E. faecalis, which was comparable to isopropranol (positive control). In the present study, self-etching DBS exhibited higher antimicrobial activity than tested total-etching adhesives against E. faecalis.

Effect of saliva and blood contamination on the shear bond strength of fifth-, seventh-, and eighth-generation bonding agents: An in vitro study.

Aim:To evaluate the bond strength of different adhesives after contamination with saliva and blood at various steps of application.Materials and Methods:Buccal surfaces of 180 human premolars were sliced to expose dentin. The specimens were randomly divided into six groups (n = 30), in which saliva and blood were used as contaminants in three groups each. The groups were further divided according to the generation (fifth – OptiBond Solo Plus Kerr, USA; seventh – OptiBond All-In-One Kerr, USA; eighth – Futurabond DC, Voco, Germany) of the adhesive used. Effect of contaminant application both before and after polymerization of the adhesive was evaluated. Composite cylinders were fabricated on exposed dentinal surfaces and were subjected to shear bond strength test. The results were subjected to one-way analysis of variance and t-test.Results:The eighth-generation adhesive showed the highest mean shear bond strength, followed by fifth- and seventh-generation adhesive. Salivary contamination resulted in greater decrease of bond strength when contaminated before polymerization. However, the results were vice versa when blood contamination was done, except in the case of fifth-generation adhesive. Blood contamination produced the lowest shear bond strength in all conditions.Conclusion:The eighth-generation adhesives showed the highest and blood contamination the lowest bond strength in all conditions.

Comparison of traditional and simplified methods for repairing CAD/CAM feldspathic ceramics.

PURPOSETo evaluate the adhesion to CAD/CAM feldspathic blocks by failure analysis and shear bond strength test (SBSt) of different restorative systems and different surface treatments, for purpose of moderate chipping repair.MATERIALS AND METHODSA self-adhering flowable composite (Vertise Flow, Kerr) containing bi-functional phosphate monomers and a conventional flowable resin composite (Premise Flow, Kerr) applied with and without adhesive system (Optibond Solo Plus, Kerr) were combined with three different surface treatments (Hydrofluoric Acid Etching, Sandblasting, combination of both) for repairing feldspathic ceramics. Two commercial systems for ceramic repairing were tested as controls (Porcelain Repair Kit, Ultradent, and CoJet System, 3M). SBSt was performed and failure mode was evaluated using a digital microscope. A One-Way ANOVA (Tukey test for post hoc) was applied to the SBSt data and the Fisher's Exact Test was applied to the failure analysis data.RESULTSThe use of resin systems containing bi-functional phosphate monomers combined with hydrofluoric acid etching of the ceramic surface gave the highest values in terms of bond strength and of more favorable failure modalities.CONCLUSIONThe simplified repairing method based on self-adhering flowable resin combined with the use of hydrofluoric acid etching showed high bond strength values and a favorable failure mode. Repairing of ceramic chipping with a self-adhering flowable resin associated with hydrofluoric acid etching showed high bond strength with a less time consuming and technique-sensitive procedure compared to standard procedure.

Effect of Airborne Particle Abrasion on Microtensile Bond Strength of Total-Etch Adhesives to Human Dentin.

Aim of this study was to investigate a specific airborne particle abrasion pretreatment on dentin and its effects on microtensile bond strengths of four commercial total-etch adhesives. Midcoronal occlusal dentin of extracted human molars was used. Teeth were randomly assigned to 4 groups according to the adhesive system used: OptiBond FL (FL), OptiBond Solo Plus (SO), Prime & Bond (PB), and Riva Bond LC (RB). Specimens from each group were further divided into two subgroups: control specimens were treated with adhesive procedures; abraded specimens were pretreated with airborne particle abrasion using 50 μm Al2O3 before adhesion. After bonding procedures, composite crowns were incrementally built up. Specimens were sectioned perpendicular to adhesive interface to produce multiple beams, which were tested under tension until failure. Data were statistically analysed. Failure mode analysis was performed. Overall comparison showed significant increase in bond strength (p < 0.001) between abraded and no-abraded specimens, independently of brand. Intrabrand comparison showed statistical increase when abraded specimens were tested compared to no-abraded ones, with the exception of PB that did not show such difference. Distribution of failure mode was relatively uniform among all subgroups. Surface treatment by airborne particle abrasion with Al2O3 particles can increase the bond strength of total-etch adhesives.

Reparability of two different CAD/CAM polymer materials using a light-cured composite and universal adhesives

ObjectiveTo evaluate the reparability of CAD/CAM polymer materials with universal adhesive systems. MethodsEighty blocks of polymethyl methacrylate (PMMA) and eighty blocks of polyoxymethylene (POM) were milled by the manufacturer (7mm of diameter and 4mm height). The top surface of all specimens was abraded with 50μm Al2O3. The 80 specimens of each material were randomly allocated to four experimental groups (n=20) according to the adhesive system used: OptiBond XTR, Futurabond M+, Scotchbond Universal or OptiBond Solo Plus. Each adhesive and the repairing composite resin (GrandioSO) were applied according the manufacturer's instructions. Specimens were stored in distilled water at 37°C for 48h and submitted to shear bond strength (SBS) tests. Fracture surfaces were observed and classified as: adhesive, cohesive or mixed type. SBS data were analysed with 2-way ANOVA and Kruskal–Wallis and Mann–Whitney tests were used to failure mode data (α=0.05). ResultsThe mean SBS yielded with PMMA specimens was significantly (p<0.001) higher than with POM. There were no statistical (p=0.062) differences between adhesive systems. Statistically significant (p<0.001) differences were found between failure mode observed in the two polymeric materials. No cohesive failure was obtained, with the POM specimens having mostly adhesive failures, in contrast with the PMMA with mostly mixed failures. No significant (p=0.925) differences in failure mode were identified between adhesives. ConclusionIt is possible to achieve an adequate adhesion bond to POM and PMMA. SBS values were higher in PMMA specimens than to POM but no differences were found between adhesive systems.

Solvent type influences bond strength to air or blot-dried dentin.

BackgroundAir-drying of etched and rinsed dentin surface may force the exposed collagen fibrils to collapse. Blot-drying is an alternative method to wipe the excess water from the dentin surface without compromising the monomer penetration. Contemporary total etch adhesives contain ethanol/water or acetone as solvent in which resin monomers are dissolved. Solvent type of the adhesive system has an important role in bonding to dentin. An adhesive containing tertiary butanol as an alternative solvent has been in the market. Purpose of this study is to determine the shear bond strengths of three total-etch adhesives with different solvents (acetone, ethanol or tertiary butanol) applied to air or blot dried moist dentin.MethodsSixty extracted non-carious human third molars were divided into three main groups according to solvent content of the adhesives [acetone based - One Step (OS, Bisco, IL, USA); ethanol/water based - Optibond Solo Plus (OB, Kerr, CA, USA); and tertiary butanol based - XP Bond (XP, Caulk/Dentsply, DE, USA)]. Each main group was divided into two groups according to drying methods (blot or air) (n = 10). Shear bond strengths (SBS) were measured. Data were analyzed by Student’s t test and Tukey HSD test (p < 0,05).ResultsXP showed highest SBS values in both drying methods applied (p < 0.05). Drying method did not influence the SBS in OS and OB (p > 0.05). XP-blot produced significantly higher SBS than XP-air (p < 0.05).ConclusionsTertiary butanol based adhesive showed higher bond strength values than ethanol or acetone based adhesives. Blot drying of dentin improved the bond strength values of tertiary butanol based adhesive. Further research is necessary to determine in vivo and in vitro performance of tertiary butanol based adhesives.

Effect of six month storage on microtensile bond strength of new elective etching adhesive system on dentin in self-etching or etch-and-rinse approach

Abstract The aim of this study was to evaluate the microtensile bond strength (μTBS) to dentin of an elective etching adhesive system applied in etch-and-rinse (ER) or self-etching (SE) mode after 6-months of storage in water. Thirty-six caries-free, human third molars were collected and stored in a 0.1% thymol solution. Dentin surfaces were exposed by 600-grit silicon carbide paper and teeth were divided into six groups ( n = 6), according to the adhesive systems: a 2-step SE system, Clearfil SE Bond (CSE); a 1-step SE adhesive Adper Prompt L-Pop (LPOP); Scotchbond Universal applied as a 1-step SE adhesive (SBU-SE) and applied as a 2-step ER adhesive (SBU-ER); and two 2-step ER adhesives: Adper Single Bond Plus (SBP) and Optibond Solo Plus (OSP). Composite build-ups were constructed with TPH3 and cured in three increments of 2 mm each. Specimens were sectioned with a slow-speed diamond saw under water in X and Y directions to obtain bonded beams that were tested to failure in tension at a crosshead speed of 1.0 mm/min after one week or 6 months of storage in water. Statistical analyses were computed using Repeated-Measures ANOVA and Fisher’s LSD Tests ( α = 0.05). There were no significant differences between 1-week and 6-months. SBU-ER and SBUSE showed the highest μTBS values and statistically differed from LPOP (Fisher’s LSD). The SBP, OSP, and CSE groups showed intermediary μTBS and did not differ statistically from SBU-ER, SBUSE or LPOP, which presented the lowest μTBS values. The use of elective etching adhesive system in dentin with the etch-and-rinse or self-etching approach did not compromise the bond strength and showed stable bonds after six months of storage in water.

Microleakage comparison of three types of adhesive systems versus GIC-based adhesive in class V composite restorations

Background and aims: New dentin bonding agents and techniques have been developed to reduce microleakage and create higher bond strength. This in-vitro study compared the microleakage of three resin-based adhesives versus a GIC-based adhesive on class V composite restorations. Materials and Methods: Class V cavities were prepared on the buccal surfaces of 72 sound premolars, randomly assigned to six groups (n=12) and treated as follows: without any treatment (negative control group); total-etch (OptiBond Solo Plus); two-step self-etch (OptiBond XTR); one-step self-etch (OptiBond All-in-One) and GIC-based adhesive (Fuji bond LC) with pre-cure and co-cure techniques. The treated cavities were filled with a micro-hybrid resin composite (Point 4, Kerr). Following finishing and polishing procedures, the specimens were placed in 100% humidity, stored in distilled water, thermocycled and then immersed in a methylene blue, sectioned, evaluated for microleakage and scored on a 0 to 3 ordinal scale. Results: None of the adhesives tested were capable of completely eliminating marginal microleakage. There were statistically significant differences among the test groups at occlusal margins; but at cervical margins were not. The Fuji Bond LC with co-cure and control groups had significantly greater microleakage scores at the occlusal margins. At the cervical margins, the bonded restorations with OptiBond XTR and OptiBond All-in-One adhesives presented significantly lower microleakage scores. Also, there were no significant differences between the resin adhesive groups both at occlusal and cervical margins. The microleakage scores at the cervical margins were markedly higher than the occlusal margins in the groups bonded with OptiBond Solo Plus and Fuji Bond LC with pre-cure. The differences between Fuji Bond LC adhesive with pre-cure and co-cure techniques were significant. Conclusion: This study encourages application of the Fuji bond LC adhesive with pre-cure technique instead of the resin adhesives for marginal seal in class V composite restorations.

In-vitro comparison of the effect of different bonding strategies on the micro-shear bond strength of a silorane-based composite resin to dentin.

The current study evaluated the micro-shear bond strengths of a new low-shrinkage composite resin to dentin. In this in-vitro study, 70 extracted premolars were assigned to one of seven groups (n = 10): Group 1: OptiBond Solo Plus (Opt; Kerr); Group 2: SE Bond (SE; Kuraray); Group 3: Silorane System Adhesive (SSA; 3M ESPE); Group 4: OptiBond Solo Plus + LS Bond (Opt LS); Group 5: SE Bond + LS Bond (SE LS); Group 6: OptiBond Solo Plus (Opt Po); and Group 7: SE Bond (SE Po). Occlusal dentin was exposed and restored with Filtek LS (3M ESPE) in groups 1 to 5 and Point 4 (Kerr) in groups 6 and 7. After thermocycling (1000 cycles at 5/55΀C), micro-shear bond test was carried out to measure the bond strengths. The results were submitted to analysis of variance and post hoc Tukeytests (P < 0.05). Two-way ANOVA showed no significant differences between the two types of composite resin (P = 0.187), between bonding agents (P = 0.06) and between composite resin and bonding agents (P = 0.894). Because P value of bonding agents was near the significance level, one-way ANOVA was used separately between the two composite groups. This analysis showed significant differences between silorane composite resin groups (P = 0.045) and Tukey test showed a significant difference between Groups 4 and 5 (P = 0.03). The application of total-etch and self-etch methacrylate-based adhesives with and without use of a hydrophobic resin coating resulted in acceptable bond strengths.

Effect of thermocycling on the durability of etch-and-rinse and self-etch adhesives on dentin.

The objective was to compare bond strengths of adhesives with/without thermocycling and to analyze the micromorphology of resindentin interfaces. Flat dentin surfaces were prepared and divided into eight groups to bond with four etch-and-rinse adhesives (Optibond FL, Adper Scotchbond Multi-Purpose, Optibond Solo Plus, and Single Bond 2) and four self-etch adhesives (Clearfil SE Bond, Adper SE Plus, Clearfil S(3) Bond and Adper Easy Bond). Specimens were further divided into two subgroups subjected for with/without thermocycling and then subjected to both micro-tensile test and resin-dentin interface evaluation. The results revealed that there were significant differences in bond strength between the groups with and without thermocycling for all etch-and-rinse groups and for the Adper Easy Bond self-etch group (p<0.01). Clearfil SE Bond demonstrated highly durable bond strengths. Furthermore, more silver ion uptake was observed at the resin-dentin interfaces for all etch-and-rinse adhesives and Adper SE Plus and Adper Easy Bond after thermocycling.

An &amp;lt;i&amp;gt;in Vitro&amp;lt;/i&amp;gt; Comparison of Bonding Effectiveness of Different Adhesive Strategies on Erbium:Yttrium-Alluminum-Garnet Laser Irradiated Dentin

Background: To date there is not a material considered ideal for the lased dentin. Objective: To compare the bond strength to human lased dentin of self-etch and etch-and-rinse adhesive systems, a self-adhesive resin composite and a glass-ionomer cement. Methods: Forty human molars were sectioned to obtain a 2 mm-thick slab of mid-coronal dentin. The occlusal surface of each slab was polished by SiC paper (P600) for 10 s. Then an half part of dentin slabs was randomly selected for receiving treatment with 2.94 μm Er:YAG laser (DEKA, Smart 2940D Plus) with 10 Hz at 100 mJ, pulse duration of 230 μs with contact tip. Dentin slabs were randomly divided into four groups (n = 10). Six conical frustum-shaped build-ups were constructed on the occlusal surface of each dentin slab using bonding agents (OptiBond Solo Plus Group 1; OptiBond All-in-one Group 2) combined with a resin composite (Premise Flow), self-adhesive resin composites (Vertise Flow Group 3) and a glass-ionomer cement (Ketac-Fil Group 4). Specimens were subjected to μSBS test. Data were analyzed by a mixed model and Tukey’s test. Results: Measured bond strengths were (mean ± standard deviation): 20.8 ± 5.5 MPa (laser treatment) and 15.6 ± 4.5 MPa (SiC paper) for Group 1, 18.9 ± 5.3 MPa (laser treatment) and 14.0 ± 4.3 MPa (SiC paper) for Group 2, 7.9 ± 2.8 MPa (laser treatment) and 4.3 ± 2.2 MPa (SiC paper) for Group 3, 4.7 ± 1.9 MPa (laser treatment) and 2.6 ± 1.2 MPa (SiC paper) for Group 4. The inferential analysis showed that the dentin laser treatment significantly affected the bond strength within each individual group. On dentin treated with laser the bond strengths recorded for build-ups constructed with etch and rinse and self-etch adhesive systems were significantly higher than those recorded for build-ups constructed with self-adhesive resin composite and glass-ionomer cement (p < 0.0001). Similarly, on dentin treated with SiC paper the bond strengths recorded for build-ups constructed with etch and rinse and self-etch adhesive systems were significantly higher than those recorded for build-ups constructed with self-adhesive resin composite and glass-ionomer cement (p < 0.0001). Conclusion: Er:YAG laser treatment has increased the shear bond strength of all the adhesive materials used.

Evaluation of microleakage in class V composite restorations using dye penetration and micro-CT.

The aim of this study was the evaluation of microleakage in class V cavities using micro-CT imaging and dye penetration. Sixty class V cavities were prepared, randomly divided into five groups (Adper Single Bond Plus (ASB), ExciTE (EX), iBond TE (ITE), Optibond Solo Plus (OSP), Prime & Bond NT (PB)) and restored with Venus Diamond. After thermocycling and dye penetration test with 50wt% ammoniacal silver nitrate, eight samples per group were sectioned longitudinally and evaluated under a coaxial incident light microscope (enamel (E) and dentin (D) measurement in mm). The remaining samples were analyzed by counting voids in the coronal and cervical adhesive areas by means of micro-CT. In dentin, no statistically significant difference in dye penetration was found. In enamel, OSP showed significant higher microleakage than all other adhesives (p<0.001). Groups ITE, ASB, PB, and EX showed a significantly lower penetration depth in E than in D (p<0.001). The results of the micro-CT examination in dentin are contrary to the findings of the microleakage evaluation. Regarding enamel, only group PB showed significant more voids than EX in enamel (p<0.02). Within the adhesive groups, PB showed significantly more voids in E than in D (p<0.04). This test method must be optimized by developing a new leakage tracer for a better differentiation between hard tissues and dental materials. The micro-CT is not yet a vulnerable tool to evaluate the marginal integrity of resin composites.

Shear bond strength evaluation of resin composite to resin-modified glass-ionomer cement using three different resin adhesives vs. glass-ionomer based adhesive

Background: The clinical success of sandwich technique depends on the strength of resin-modified glass ionomer cement (RMGIC) bonding to both dentin and resin composite. Therefore, the shear bond strength (SBS) of resin composite bonded to RMGIC utilizing different resin adhesives versus a GIC-based adhesive was compared. Materials and methods: In this in vitro study, 84 holes (5×2 mm) were prepared in acrylic blocks, randomly divided into seven groups (n=12) and filled with RMGIC (Light-Cured Universal Restorative, GC). In the Group I; no adhesive was applied on the RMGIC. In the Group II, non-etched and Group III was etched with phosphoric acid. In groups II and III, after rinsing, etch-and-rinse adhesive (OptiBond Solo Plus); in the Group IV; a two-step self-etch adhesive (OptiBond XTR) and in Group V; a one-step self-etch (OptiBond All-in-One) were applied on the cement surfaces. Group VI; a GIC-based adhesive (Fuji Bond LC) was painted over the cement surface and cured. Group VII; the GIC-based adhesive was brushed over RMGIC followed by the placement of resin composite and co-cured. Afterward; resin composite (Point 4) cylinders were placed on the treated cement surfaces. The specimens were placed in 100% humidity at 37 ± 1°C and thermo cycled. The shear bond test was performed at a cross-head speed of 1 mm/min and calculated in MPa; the specimens were examined to determine mode of failure. The results were analyzed using one-way ANOVA and Tukey test. Results: The maximum (24.62±3.70 MPa) and minimum (18.15±3.38 MPa) SBS mean values were recorded for OptiBond XTR adhesive and the control group, respectively. The pairwise comparisons showed no significant differences between the groups that bonded with different adhesives. The adhesive failure was the most common failure mode observed. Conclusion: This study suggests that GIC-based adhesive could be applied over RMGIC as co-cure technique for sandwich restorations in lieu of employing the resin adhesives

Microleakage of Class I and II Composite Resin Restorations Using a Sonic-resin Placement System.

To determine microleakage of posterior Class I and II restorations using the SonicFill composite resin system. Eighty previously extracted third molars were randomly assigned to four preparation/restoration groups (n=20): Group A: Class I preparations restored with SonicFill system/bulk fill; Group B: Class II preparations restored with SonicFill system/bulk fill; Group C: Class I preparations restored with Herculite Ultra composite resin/incremental technique; and Group D: Class II preparations restored with Herculite Ultra composite resin/incremental technique. Class I preparations were approximately 3.0 mm in width buccolingually and 3.0 mm in depth. Class II preparations were approximately 3.0 mm in width buccolingually, 1.5 mm in axial depth, and 4.0 mm in gingival depth. In all groups, the enamel and dentin surfaces were conditioned with Kerr 37.5% phosphoric acid, followed by application of Optibond Solo Plus adhesive system. Following restoration, the specimens were thermocycled, immersed in methylene blue dye, and embedded in acrylic resin. Specimen blocks were sectioned in the mesiodistal direction, with marginal dye penetration (microleakage) examined using a 20× binocular microscope. Class I and II restoration microleakage was scored separately using a 0-3 ordinal ranking system. Statistical analyses were conducted using nonparametric testing at the p < 0.05 level of significance. Significantly less microleakage was associated with both Class I restorative groups (A and C), SonicFill bulk fill and Herculite Ultra incremental fill, compared to the Class II restorative groups (B and D), SonicFill/bulk fill and Herculite Ultra/incremental fill. According to the results of this study, the materials (SonicFill vs Herculite Ultra), C-factors, and insertion techniques (bulk vs incremental) did not appear to be significant influences with regard to marginal microleakage; however, the type of preparation cavity (Class I vs Class II) and the subsequent bonding surface (enamel vs dentin [cementum]) proved to be significant factors.

Shear Bond Strength between Fiber‐Reinforced Composite and Veneering Resin Composites with Various Adhesive Resin Systems

The aim of this research was to evaluate the shear bond strength of different laboratory resin composites bonded to a fiber-reinforced composite substrate with some intermediate adhesive resins. Mounted test specimens of a bidirectional continuous fiber-reinforced substrate (StickNet) were randomly assigned to three equal groups. Three types of commercially available veneering resin composites - BelleGlass®, Sinfony®, and GC Gradia® were bonded to these specimens using four different adhesive resins. Half the specimens per group were stored for 24 hours; the remaining were stored for 30 days. There were 10 specimens in the test group (n). The shear bond strengths were calculated and expressed in MPa. Data were analyzed statistically, and variations in bond strength within each group were additionally evaluated by calculating the Weibull modulus. Shear bond values of those composites are influenced by the different bonding resins and different indirect composites. There was a significant difference in the shear bond strengths using different types of adhesive resins (p = 0.02) and using different veneering composites (p < 0.01). Belle-Glass® had the highest mean shear bond strength when bonded to StickNet substrate using both Prime & Bond NT and OptiBond Solo Plus. Sinfony® composite resin exhibited the lowest shear bond strength values when used with the same adhesive resins. The adhesive mode of failure was higher than cohesive with all laboratory composite resins bonded to the StickNet substructure at both storage times. Water storage had a tendency to lower the bond strengths of all laboratory composites, although the statistical differences were not significant. Within the limitations of this study, it was found that bonding of the veneering composite to bidirectional continuous fiber-reinforced substrate is influenced by the brand of the adhesive resin and veneering composite.