Evaluation of Microleakage with Total Etch, Self Etch and Universal Adhesive Systems in Class V Restorations: An In vitro Study

Experimental and Chitosan-Infused Adhesive with Dentin Pretreated with Femtosecond Laser, Methylene Blue-Activated Low-Level Laser, and Phosphoric Acid

Aim: To prepare experimental adhesive (EA) with 1% and without chitosan nanoparticles on dentin conditioned with a conventional technique phosphoric acid (PA) compared with two different contemporary techniques: photodynamic therapy (PDT) and femtosecond laser (FSL). Method: The methodology consisted of synthesis of EA and 1% chitosan-modified adhesive (CMA). Scanning electron microscopy, dentin adhesive interface assessment, energy-dispersive spectroscopy, shear bond strength (SBS), degree of conversion (DC), and bond failure were assessed. Teeth were selected, disinfected, and mounted in acrylic up to the cementoenamel junction. Occlusal enamel was removed and teeth were randomly allocated into groups and conditioned. These included Group 1: samples treated with PA; Group 2: specimens conditioned with methylene blue photosensitizer (MBP) activated by PDT; and Group 3: samples conditioned with FSL. Following different conditioning regimes, specimens were bonded using 1% CMA and EA. The composite buildup was followed by SBS testing and a bond failure assessment. DC was assessed for both EA and CMA. Analysis of variance and Tukey's post hoc test were used to compare the mean and standard deviation of SBS and DC in different experimental groups, with a significance level of p < 0.05. Results: Dentin pretreated with etch and rinse demonstrated the highest bond strength with 1% CMA. Dentin conditioned with MBP activated by PDT and bonded to EA showed the lowest bond scores. Overall SBS values of 1% CMA were better than EA irrespective of the conditioning regime of dentin. The DC was higher in EA adhesive. This was followed by DC in 1% CMA. DC in EA was found to be comparable with 1% CMA. Conclusions: PA remains the gold standard for dentin conditioning. The incorporation of 1% chitosan in adhesive improves SBS and results in no change in DC. The use of FSL in dentin conditioning can be used as an alternative approach as it results in SBS within acceptable limits. The study was approved by the ethical board of King Saud University.

Impact of acid and laser etching of enamel on microleakage in different adhesive systems

This study aimed to evaluate the microleakage of light-cured and self-cured adhesives on enamel surfaces selectively etched with Er, Cr: YSGG laser or 35% phosphoric acid. A total of 60 class V cavities were prepared 1 mm above the cemento-enamel junction (CEJ). The specimens were randomly divided into six groups. Group 1: Clearfil SE Bond with no conditioning, Group 2: Tokuyama Universal Bond with no conditioning, Group 3: Clearfil SE Bond conditioned with 35% phosphoric acid, Group 4: Tokuyama Universal Bond conditioned with 35% phosphoric acid, Group 5: Clearfil SE Bond conditioned with Er, Cr: YSGG laser and Group 6: Tokuyama Universal Bond conditioned with Er, Cr: YSGG laser. Microleakage was evaluated qualitatively (visually) and quantitatively (ImageJ). The data were analyzed using IBM SPSS V23 and submitted to Kruskal-Wallis and Wilcoxon tests. The significance level was set at p < 0.05. In all evaluation methods, the microleakage scores exhibit significant differences (p*<0.001). Group 1 and Group 3 exhibited similar and lower microleakage values than the Group 5. In the occlusal margin, the microleakage values were similar in Group 2, Group 4, and Group 6, whereas in the gingival margin Group 4 showed significantly lower leakage compared to Group 2. Regardless of the etching protocols and adhesive systems used, less microleakage was observed on the occlusal surface than on the gingival surface. Phosphoric acid etching provides better results than laser etching for enamel surface treatment on both occlusal and gingival surfaces.

Comparative Evaluation of Microleakage With Total-Etch, Universal (Self-Etch Mode), and Nano Adhesive Systems in Class V Composite Restorations: An In-Vitro Study

OBJECTIVES

The adhesion of bonding agents and their longevity are of interest to dentistry. Microleakage remains the major cause of composite restoration failures, which in turn depends on bonding between the restorative material and tooth substrate. The objective of this study is to evaluate and compare the microleakage with total-etch, universal, and nano adhesive systems in Class V composite restorations, utilizing a dye penetration method.

METHODS

Forty-five extracted premolars were included in the present study, and a Class V cavity on the facial surface of each tooth was prepared. The samples were divided into three groups of 15 teeth each depending on the bonding agents used, following which composite restoration was done. Specimens were thermocycled, and nail varnish was applied except around the restorations. Specimens were then immersed in 2% methylene blue for 24 hours and rinsed; sectioning was done and viewed under a stereomicroscope with 10X magnification.

RESULTS

The mean microleakage score was reported to be significantly higher in the universal adhesive system in the self-etch mode (3.60 ± 0.55) when compared with the total-etch adhesive system (2.40 ± 0.55) and least in the nano adhesive system (1.20+.45) (p value <.05).

CONCLUSION

The study findings revealed that nano adhesives showed lesser microleakage as compared to total-etch and universal adhesive systems.

CLINICAL SIGNIFICANCE

The study strengthens the findings that the nano adhesives have reduced microleakage, resulting in better marginal integrity and increased longevity of restoration. This study signifies that an eighth-generation bonding agent is reported to be better than the other bonding agents used in this study.

The effects of dental adhesives total etch; self-etch and selective etch application procedures on microleakage in class II composite restorations

Purpose

The aim of this study is to evaluate the amount of microleakage resulting from the application of self-etch, selective etch, etch-and-rinse of adhesive systems in class II cavities.

Materials and methods

Four adhesive systems with etch-and-rinse, selective etch and self etch methods were used on the extracted teeth. All groups were restored with G-aenial A'CHORD (Nanohybrid) (GC, Tokyo, Japan) A2 composite. After 1000 thermal cycles were applied to the teeth after restoration, the samples were kept in 0.5% basic fuchsin for 24 hours. Microleakage values formed after dye penetration with basic fuchsin were determined quantitatively by scoring method on sections taken from each sample in the mesiodistal direction. One-way Analysis of Variance (ANOVA) and Tukey test were used for statistical analysis of the data (p<0.05).

Results

While there was no statistically significant difference between the etch-and-rinse and selective etch applications of adhesive systems (G2-Bond Universal, Clearfil Tri-S Bond Universal Prime&Bond Universal and Tokuyama Bond Force II) (p>0.05), there was a statistically significant difference in self-etch application (p<0.05). As a result of Prime&Bond Universal's self-etch application, it showed statistically more microleakage than the other three adhesive systems (p<0.05).

Conclusion

It has been observed that additional etching of enamel and/or dentin with phosphoric acid reduces the amount of microleakage.

Microleakage in indirect onlay restorations cemented with three different types of adhesives: An in vitro study

Background

To evaluate the in vitro degree of marginal microleakage in indirect Class II onlay restorations cemented with dual self-adhesive, universal adhesive and dual adhesive.

Material and Methods

In the present in vitro experimental study, a total of 54 human premolar teeth were prepared and divided into three equal groups (n = 18) for placement of onlay-type restorations cemented with A: Allcem™ dual-cure adhesive cement), B: RelyX™U200 dual-cure self-adhesive cement and C: RelyX™ Ultimate universal adhesive cement. All restorations were subjected to 10,000 thermocycles between 5°C and 55°C and immersed in a 1M silver nitrate solution for 6 hours. The crowns were then sectioned mesiodistally and observed under a stereo microscope to determine the degree of marginal microleakage in the cervical area.

Results

The onlay restorations cemented with RelyX Ultimate did not present microleakage in the majority of cases (77.8%). Restorations cemented with RelyX U200 showed predominantly microleakage up to the pulp floor in 83.3% of the total, being this significantly higher microleakage than in restorations cemented with RelyX Ultimate and Allcem Dual (p<0.001 and p<0.001 respectively). There was no significant difference in microleakage between the last two mentioned cements (p=0.255).

Conclusions

Allcem dual adhesive cement and RelyX Ultimate universal adhesive showed significantly less microleakage than RelyX U200 dual-curing self-adhesive cement at the cervical level, with predominantly no microleakage and microleakage down to the enamel, respectively. The use of RelyX Ultimate cement in indirect restorations is recommended as it showed better marginal adaptation. Key words:Microleakage, human teeth, adhesion, adhesive cement, thermal cycling, onlay restoration.

Renewal MI Dental Composite Etch and Seal Properties

This study's aim was to assess whether the Renewal MI composite can self-etch enamel, seal sound cavities, and stabilize demineralized dentine. Etching was assessed using scanning electron microscopy (SEM). Cavity sealing was quantified using the ISO-11405 dye microleakage test. Demineralized dentine stabilization was evaluated by visualizing resin tag formation, enzyme activity and mineral precipitation at the adhesion interface. Renewal MI provided a mild etching of sound enamel in comparison with 37% phosphoric acid. It provided a comparable seal of sound cavities to Z250/Scotchbond Universal adhesive and a superior seal to Activa, Fuji IX and Fuji II LC. With demineralized dentine, Renewal MI formed 300-400 µm resin tags covering 63% of the adhesion interface compared with 55 and 39% for Z250/Scotchbond and Activa. Fuji IX and Fuji II LC formed no resin tags. A higher tag percentage correlated with lower surface enzyme activity. Unlike Activa and Fuji II LC, Renewal MI promoted mineral precipitation from simulated body fluid, occluding adjacent dentinal tubules within 6 months. These novel etching and sealing properties may facilitate Renewal MI's application in minimally invasive dentistry.

Microleakage Evaluation in Class V Cavities Restored with Five Different Resin Composites: In vitro Dye Leakage Study

Purpose

Restorative materials and techniques have improved the clinical success of a variety of restorative procedures. Despite these new improvements, microleakage remains one of the leading causes of restoration failure and may lead to postoperative sensitivity, enamel microcracks, marginal staining, discoloration, recurrent caries, and deformation of teeth. This study evaluated microleakages of five recent resin composites in class V cavities.

Materials and Methods

Standardized class V cavities were prepared on the labial surfaces of one hundred extracted intact and noncarious human permanent premolar teeth. The cavities were divided into five groups (n=20) according to the resin composite material. Groups: A1, A2, A3, A4 and A5 were restored with Omnichroma, Spectrum, Mosaic, Tetric N-Ceram and Harmonize, respectively. The teeth were stained with methylene blue and then sectioned, and the extent of dye penetration was examined under a stereomicroscope and scanning electron microscope (SEM) to evaluate microleakage. One-way ANOVA test was used to statistically analyze the data. Statistical Package for Social Sciences Computer Software (SPSS) version 15.0 was used.

Results

Dye penetration was observed at the tooth-restoration interface in all the studied samples, with varying degrees of penetration. At the cervical margins of the cavities, no statistically significant difference in the microleakage scores was observed (P=0.16). At the cavity floor, no statistically significant difference in microleakage scores was observed (P=0.74). Omnichroma resin composite had the highest microleakage results.

Conclusion

Nanohybrid resin composites showed less microleakage than other resin composites. Among all the groups, Omnichroma showed the highest microleakage at the cavity floor and at the cervical areas.

Clinical Significance

In light of our findings, nanohybrid resin composites appear to be capable of reducing microleakage, and the results reported herein must be verified by additional clinical trials.

Evaluation of Microleakage of Micro Hybrid Composite Resins versus Chitosan-Incorporated Composite Resins When Restored in Class V Cavities Using Total Etch and Self-Etch Adhesives: An In vitro Study

Aim:

To evaluate the in-vitro microleakage of traditional micro hybrid composite resin and 0.2% chitosan-incorporated composite resin when restored in Class V cavities using total etch versus self-etch adhesives after storing in artificial saliva for 24 h.

Materials and Methodology:

Sixty permanent maxillary premolars collected and Class V cavities were prepared on buccal surface of each tooth (dimensions: mesio-distally 3 mm, occluso cervically 2 mm, and depth of 1.5 mm) and restored with Group 1: micro hybrid (30 teeth) and Group 2: chitosan-incorporated composite (30 teeth), which was further subdivided into: (a) 15 teeth using total-etch adhesives. (b) 15 teeth using self-etch adhesives. Next dye extraction test was carried out using spectrophotometer.

Results:

Comparison within groups: In Group 1: Self-etch demonstrated less microleakage (0.0129) compared with total etch (0.0183). The difference was statistically significant, and in Group 2: No statistically significant difference was found in mean microleakage scores after using either self-etch (0.0118) or total etch adhesives (0.0120).

Conclusion:

It can be concluded that chitosan-incorporated composite seems to have improved mechanical properties with a stable bond when used with either self-etch or total etch adhesives in addition to being antibacterial. It may be clinically useful in restoring Class V cavities in patients with high caries risk. However, further in vitro and in-vivo studies need to be carried out.

Effect of Different Bonding Techniques on Marginal Adaptation of Harmonize Composite Resin at Different Storage Times

Aim:

The aim of this study is to evaluate the outcome of diverse bonding methods on marginal adaptation of harmonize composite at altered times of storage.

Materials and Methods:

The study was done on 120 upper premolars with two adhesive systems (n = 60), self-etch, and total-etch type. Sixty teeth of each method were stored at three different times (n = 20) 1 day, 3, and 6 months. Class II cavities were made in all teeth restored with Harmonize composite incrementally. Then, each tooth was sectioned into two halves in buccolingual direction and observed with stereomicroscope for detecting any gaps and scanning electron microscope to assess resin-dentin junction.

Results:

Mean gap area was more in the self-etch group at the cervical and occlusal margins. Storage period of 6 months revealed significantly highest mean gap area.

Conclusions:

Total-etch system showed better marginal adaptation than the self-etch system and storage of resin in water has unfavorable marginal adaptation.

Shear bond strength of acid and laser conditioned enamel and dentine to composite resin restorations: An in vitro study

Objective

To compare the shear bond strength of enamel or dentin conditioned with either Er,Cr:YSGG (erbium, chromium: yttrium–scandium–gallium–garnet) laser or phosphoric acid to composite resin restoration.

Material and methods

Forty posterior human extracted teeth were used. After mesiodistal sectioning of the teeth crowns, the samples were randomly divided into two groups—in the first group (E), bonding was performed on the enamel after roughening and in the second group (D), the enamel was removed and bonding was performed on the dentin. These groups were further randomly divided into two subgroups according to the type of etching (n = 20 each). In the acid‐etched groups (EA and DA), the surfaces were etched with 37% phosphoric acid. In the laser‐conditioned groups (EL and DL), the surfaces were conditioned with Er,Cr:YSGG laser. Total‐etch adhesive system was used to bond all the 80 specimens resin composite. The composite was vertically light‐cured, and the specimens were subjected to a shear bond strength test. Modes of bond failure were determined with a stereomicroscope.

Results

The highest shear bond strength was observed for the DA group (16.25 ± 1.10 MPa, p < 0.0001), whereas the lowest was observed for the DL group (8.56 ± 0.67 MPa). The adhesive failure mode was the most frequently observed in all groups.

Conclusions

The shear bond strength of composite resin bonded to enamel and dentin etched with phosphoric acid was higher than when conditioned with Er,Cr:YSGG laser. Thus, laser conditioning is not recommended.

In Vitro Analysis of Quality of Dental Adhesive Bond Systems Applied in Various Conditions

Introduction: There are several methods of reducing a microleakage, and one of them is choosing appropriate adhesive material. The aim of the work was the in vitro analysis of 4 bonds: 3M ESPE “Single bond”, Dentsply “Prime and Bond Active”, Coltene “One Coat 7 Universal”, and Kuraray “Clearfil Universal Bond Quick”. Material and methods: 136 healthy molar teeth were collected and randomly split into 4 groups and Vth Class cavities were prepared. Chosen adhesives were used in four groups of teeth with the same composite. Teeth were the thermocycled, sealed, covered with lacquer, and submerged in 1% methylene blue solution for 24 h. After the thermocycling, the vertices of each tooth were sealed using dental wax. Each tooth was then fully covered with lacquer. All teeth were then submerged into 1% methylene blue solution for 24 h in room temperature. In the next step they were transversely cut through a center of restoration. The Olympus BX43 microscope was used to photograph each cut tooth. With the usage of Olympus stream software, measurement of the dye’s leakage was performed. Results. The statistical analysis proved that the most effective material when applied to ideally prepared cavity surface was Dentsply “Prime and Bond Active”. The second material was 3M ESPE “Single Bond”, third—Coltene “One Coat 7 Universal” and fourth—Kuraray “Clearfil Universal Bond Quick”. The most effective material applied to a too-dry surface was Dentsply “Prime and Bond Active”, second—3M ESPE “Single Bond”, third—Coltene “One Coat 7 Universal” and fourth—Kuraray “Clearfil Universal Bond Quick”. When it comes to too damp surfaces the best results were obtained with Dentsply “Prime and Bond Active” then Coltene “One Coat 7 Universal”, 3M ESPE “Single Bond” and Kuraray “Clearfil Universal Bond Quick”. Conclusion: The level of cavity dampness influences the quality of adhesives. Better results are obtained with over-dried surfaces than over-damp, which is connected with the dilution of the material.

Effect of Diode Laser (810 nm) Irradiation on Marginal Microleakage of Multi-mode Adhesive Resins in Class V Composite Restorations

Introduction: Some studies have shown that laser irradiation on unpolymerized adhesives can improve composite-dentin adhesion. The aim of the present study was to evaluate the effect of the diode laser (810 nm) on the microleakage of multi-mode adhesive systems at enamel and dentin margins of composite restorations. Methods: Classic class V boxes were prepared on 48 sound premolar teeth and randomly divided into 6 groups (n=16). In the control groups, Scotchbond Universal (SBC), G-Premio (GBC), and Ambar U (AMC) were used by a self-etch mode. In the test groups (SBL, GBL, ABL), the 810 nm diode laser was irradiated (1 W) for 10 seconds before the polymerization of the adhesive. The boxes were restored by the resin composite. After finishing and polishing, the samples were thermocycled (5°C to 55°C) for 1000 cycles and then immersed in 0.1% methylene blue dye (48 hours). Dye penetration through the gingival and occlusal margins was measured by Stereomicroscope. The data were analyzed at the 5% significance level using Kruskal-Wallis and Mann-Whitney U tests. Results: Significant differences were found between the control and test groups (P < 0.05). The occlusal margins of the SBL and GBL groups and the cervical margin of the SBL group exhibited the lowest microleakage (P < 0.05). The AM control group showed maximum microleakage at cervical and occlusal margins. Conclusion: The irradiation of the 810 nm diode laser on the unpolymerized universal adhesive systems in a self-etch mode caused a significant reduction in enamel and dentin marginal microleakage of composite restorations.

Multi-Mode adhesives performance and success/retention rates in NCCLs restorations: randomised clinical trial one-year report

Aim: Compare clinical performance and success/retention rates of two multi-mode (MM) adhesives, applied in self-etch (SE) or etch-and-rinse (ER) modes, with SE-all-in-one adhesive (SE/SE with enamel etching) in NCCL restorations at one-year follow-up.

Material and methods: Prospective, double-blind RCT approved by the University Fernando Pessoa and the National-Clinical-Research-Ethics Committees (CEIC-20150305), ClinicalTrials.gov registered (NCT02698371), in 38 participants with 210 restorations (AdmiraFusion^®) randomly allocated to six groups (Adhesives_Adhesion mode), each with 35 restorations: G1-Control Futurabond^®DC_SE; G2-Control Futurabond^®DC_SE with enamel etching; G3-Futurabond^®U_ER; G4-Futurabond^®U_SE; G5-Adhese^®Universal_ER; G6-Adhese^®Universal_SE. Restorations evaluated at baseline and one-year by three calibrated examiners (ICC ≥0.952) using FDI criteria and statistical analysis with nonparametric tests (alpha = 0.05).

Results: At one-year recall 36 participants, 199 restorations were available for examination; five (2.5%) restorations (G1 n = 2; G2, G3, G4 n = 1) were lost due to retention (p > .05); G1 showed less satisfying marginal adaptation (p < .05) than G2 and MM adhesives groups, particularly G6. Overall success rates (p > .05) were: 93.9% (G1), 97.0% (G2; G3; G4) and 100.0% (G5; G6).

Conclusions: MM adhesives (Futurabond^®U and Adhese^®Universal) showed similar and acceptable performance/success rates but also better clinical outputs than the SE-all-in-one adhesive (Futurabond^®DC), particularly in SE mode. Success and retention rates were similar and not dependent on materials or adhesion modes.

Adhesive systems effect over bond strength of resin-infiltrated and de/remineralized enamel

Background: The purpose of this study was to evaluate the effect of different bonding agents on bond-strength to demineralized enamel after remineralizing treatments and resin infiltration. Methods: Buccal enamel of 120 bovine incisors was polished and then were divided into five experimental groups: SE (sound enamel); DE (demineralized enamel); AS (demineralized enamel immersed in artificial saliva for eight weeks); NaF (demineralized enamel treated with 0.05% sodium fluoride solution (one minute) for eight weeks); Ic (demineralized enamel infiltrated with a low-viscosity resin (Icon-DGM). These groups were subdivided according to adhesive system used: self-etching adhesive Adper Easy One (3M/ESPE) and etch-and-rinse adhesive Single Bond (3M/ESPE). The composite resin blocks were fabricated using a Teflon matrix. A thermomechanical cycling machine was used to carry out the artificial aging of the specimens and thus were sectioned into sticks. The microtensile tests were performed using a universal testing machine at a cross-head speed of 1 mm/min. Data (in MPa) were subjected to two-way ANOVA and Tukey's tests (5%). Results: Significant differences were found for both factors tested and interactions (p<0.05). Tukey's test results of µTBS (mean ± SD) were: etch-and-rinse SE (28.79±3.93); DE (30.41±7.22); AS (29.03±3.33); NaF (29.81±4.06)a; Ic (29.47±5.5);  and self-etching SE (30.37±6.96); DE (14.62±4.47); AS (9.79±2.32); NaF (9.36±2.31); Ic (30.78±8.68).   Conclusions: Resin infiltration did not affect the bond strength of demineralized enamel for both adhesive systems tested. For etch-and-rinse adhesive, no differences were observed for the tested groups. For self-etching adhesive, only the resin-infiltrated group showed similar bond strength to sound enamel. Both etch-and-rinse and self-etching adhesive systems can be used in resin-infiltrated enamel, if a composite restoration needs to be further performed. In enamel that has undergone the de/remineralization process, the use of a total-etch adhesive might be preferable for the restorative procedure.

Effect of Preetching on Microleakage with All-In-One Adhesives Using Calcium-Based Desensitizers: An In vitro Study

Objectives

The aim of this study was to evaluate the effect of calcium-based desensitizers on the microleakage with and without preetching enamel in Class V cavities restored with all-in-one adhesives.

Materials and Methods

Class V cavities were prepared on the buccal surfaces of 100 extracted human premolars. A total of 100 box-shaped cavities were divided into five groups (n = 20). Group 1 - no desensitizer was applied and Groups 2 and 4 - desensitizer (CCP-ACP and Novamin) was applied, respectively, followed by the application of G-Bond and restored with composite restoration. Groups 3 and 5 are same as Group 2 and 4, but preetching of enamel was done for 3 s after desensitizers application. The teeth were thermocycled and the specimens were examined for microleakage using methylene blue as a marker. The teeth were sectioned buccolingually and evaluated for microleakage under stereomicroscope and the scores obtained were analyzed with Kruskal-Wallis and Mann-Whitney tests.

Results

Statistically significant difference existed between Groups 2 and 3 (P < 0.05). There was also statistically significant difference between Groups 4 and 5 (P < 0.05). Groups 3 and 5 showed significantly less microleakage (P < 0.05). No statistically significant difference in microleakage values was observed between the two desensitizers CCP-ACP and Novamin.

Conclusion

The application of calcium-containing desensitizers with selective etch enamel technique in all-in-one adhesives could be considered an advisable procedure to minimize microleakage.