Self-etch Group Research Articles

Efficacy of Potassium Iodide and Glutathione for Correlation of Dentin Discoloration Caused by Silver Diamine Fluoride.

This study aimed to investigate and contrast the degree of dentin discoloration resulting from the application of silver diamine fluoride (SDF) alone, SDF in combination with potassium iodide (KI), and SDF in combination with glutathione. The aim was to assess the effectiveness of these combinations in reducing the aesthetic issues associated with SDF treatment in minimally invasive dentistry and preventive procedures. We conducted this in-vitro study on 136 permanent molar teeth. The teeth were randomly assigned to two main groups of total-etch and self-etch and four subgroups of control, SDF, SDF plus KI, and SDF with glutathione. The teeth underwent colorimetry before and 1 week after applying materials to compare the color change. We mounted the teeth in acrylic resin 1 mm below their cementoenamel junction. A low-speed diamond saw and 600-grit silicon carbide abrasive paper eliminated the occlusal enamel for 10 seconds under water coolant, exposing the dentin. The teeth were then immersed in a demineralizing solution (pH of 4.4, 50 mmol acetate, 2.2 mmol potassium dihydrogen phosphate, and 2.2 mmol calcium chloride) for 7 days at 37°C to induce dentin demineralization and simulate demineralized dentin artificially. The teeth were then gently polished with 600-grit silicon carbide abrasive paper to create a standard smear layer and eliminate the demineralized dentin layer. 136 teeth were evaluated in the total-etch (n = 68) and self-etch (n = 68) groups. Glutathione and KI significantly decreased the discoloration caused by SDF (P<0.05). No significant difference was noted in color change between SDF/glutathione and SDF plus KI groups (P > 0.05). In self-etch groups, glutathione yielded an ∆E=4.12, while KI yielded an ∆E=4.44, with no significant difference. The application of glutathione and KI can significantly decrease dentin discoloration caused by SDF.

Comparative evaluation of bonding performance between universal and self-etch adhesives: In vitro study

ObjectiveThis work aimed to assess the bonding performance of universal adhesive and self-etch adhesives, and a comparative study was conducted using the same acid etching mode. MethodsThe selective acid-etching mode was used to simulate bonded restorations to teeth defects of isolated human molars including enamel and dentin. Microtensile bond strength and microleakage of all adhesives were tested and compared after 24 h and 5000 thermocycles, respectively. The morphology of the adhesive interfaces was observed by scanning electron microscopy (SEM) and fluorescent staining. ResultsThe bond strength and microleakage of Single Bond Universal (SBU) adhesive are comparable to those of self-etch adhesives, although Clearfil Tri-S Bond (S3) exhibited significantly lower bond strength compared to other two self-etch groups evaluated. No significant differences were found in the microleakage resistance of these four adhesives, suggesting their similar effectiveness in sealing the margins of the restorations, although SBU showed the highest resistance of microleakage. The SEM and fluorescent staining results of the resin-dentin interfaces further revealed the formation of abundant resin tags for all adhesives. ConclusionsSelf-etch adhesives evaluated in this study performed similarly to universal adhesives in selective acid-etch mode for bond strength and microleakage resistance. Both types of adhesives exhibited effective penetration capabilities into the dentinal tubules. Clinical significanceDuring the adhesion processes involving both dentin and enamel, self-etch adhesives can serve as alternatives to universal adhesives in selective acid-etch mode.

Influence of Age and Etching Technique on the Microleakage in Class-V Composite Restorations: An In-vitro Study

Aim: The objective of current research was to evaluate the impact of patient’s age on the microleakage in Class-V composite restorations. Study Design: Research article. Methodology: 30 permanent human molars from various age groups (n=10 each) were collected. The teeth were categorized based on age, Group I (less than 30 years), Group II (30-50 years), and Group III (more than 50 years), standardized Class-V tooth preparations were prepared. Subsequently, each group has further two subgroups: selective enamel etching (Sb A) and self-etching (Sb B), using universal adhesive (3M single bond). Following this, restoration of teeth were done using Z350 composite, and microleakage was analysed by dye penetration method via stereomicroscope and corresponding scoring were recorded. Mann- Whitney Test and Kruskal- Wallis Test was done for statistical analysis. Results: The group III subgroup A and B showed highest microleakage (2.40 and 2.80) followed by group II (1.20 and 1.60) and least in group I (0.40 and 0.80) respectively (P&lt;.005). Therefore, more microleakage was seen with self-etch group as compare to selective etch. Conclusion: Influence of age of patient had significant impact on Class-V restorations. Also, more microleakage was observed in self-etch group as compared to that of selective etch technique.

Evaluation of Microvoid and Microleakage Potential of Bulk-Fill Resin Composites in MOD Restorations

Background: Polymerization shrinkage and microvoid formation has been a significant problem giving way to resin composite failure. The aim of this study was to evaluate the microvoid potential and microleakage of two bulk-fill and a microhybrid resin composite applied with different adhesive materials. Materials and Methods: MOD cavities were prepared in 60 endodontically treated maxillary premolars. The teeth were divided into six different groups (n = 10) according to adhesive systems (Gluma (Kulzer), OptiBond FL (Kerr) and resin composite materials EverX Posterior (GC) and Filtek One Bulk Fill (3M ESPE). An aging procedure with 5000 cycles of thermal cycling was applied. All teeth were individually scanned with micro-computed tomography. A Shapiro–Wilk test, two-way MANOVA, and Bonferroni analysis were used for statistical tests. Results: Self-etch groups showed more microleakage than total-etch groups. Minimum microleakage was observed in Filtek One Bulk Fill groups, whereas G-aenial Posterior groups showed maximum microleakage. Conclusions: Filtek One Bulk Fill (3M ESPE) resin composite was found to be more effective in reducing microvoid formation in MOD cavities when applied with total-etch adhesive systems. However, EverX Posterior (GC) and G-aenial Posterior (GC) showed less microvoid formation with self-etch adhesive systems.

Longitudinal bond strength of a universal adhesive and chemical dentin characterization under different acid etching protocols.

This study aimed to analyze the longitudinal bond strength of a universal adhesive and chemically characterize the dentin substrate under different acid etching protocols. Dentin samples were etched with polyacrylic acid 25% (PAA) for 10 seconds (n=3) and phosphoric acid 32% (PA) for 15 seconds (n=3) and analyzed by Fourier transform infrared spectroscopy - attenuated total reflectance (FTIR-ATR) before and after treatment. For collagen degradation, samples (n=12) were divided into 3 groups: PAA, PA, and Deionized water (control), and analyzed by the quantity of solubilized type I collagen C-terminal cross-linked telopeptides and solubilized C-terminal peptide in relation to total protein concentration (ICTPtp and CTXtp) and by their ultimate tensile strength (UTS). For the adhesive interface analysis, dentin samples (n=72) were divided into 3 groups: PAA, PA, and Self-etch (SE), and subdivided into 2 groups: 24 h (baseline) and 1 year. The following tests were performed: microtensile bond strength (μTBS) (n=48), scanning electron microscopy (SEM) (n=12), and nanoleakage (n=12). The FTIR of PAA showed lower reduction of the peaks in the phosphate group when compared to PA. For ICTPtp, PA showed a significantly higher value. For CTXtp, PA and PAA groups failed to statically differ from each other. UTS was significantly lower for PA. For μTBS, storage time significantly affected bond strength. The results were unaffected by the etching protocol. For SEM, after 1 year, PA had little evidence of degradation in the upper third of the adhesive interface in comparison to the other groups. Nanoleakage showed no considerable silver impregnation after 1 year in the SE group. The use of PAA prior to a universal adhesive (when compared to PA) represents a less aggressive type of etching to dentin. However, self-etching still seems to be the best option for universal adhesive systems that have functional monomers in their composition.

Comparative Evaluation of Application of Universal Bonding on the Microtensile Bond Strength of Light Cure and Dual Cure Composites Bonded to Dentin.

Objectives: There is limited knowledge on the efficacy of universal adhesives when used in different etching modes. The aim of this study was to evaluate the microtensile bond strength (µTBS) to dentin using universal adhesives with light-cure and dual-cure composites. Materials and Methods: In this in vitro experimental study, the occlusal third of 60 caries-free human molars were removed and the exposed surfaces were treated and allocated to 10 groups (N=6). Two different bonding agents (Single Bond Universal, G-Premio) were used to bond 2 different composite resins (Z250 light-cure and CoreFlo DC dual-cure) to dentin, using etch-and-rinse (E&R) and self-etch (SE) modes. Single Bond 2 was applied in E&R mode on wet dentin to serve as control. The specimens were sectioned into 1×1 mm2 sticks with a precision saw. A microtensile testing machine was used to measure the µTBS of the specimens with a crosshead speed of 0.5 mm/min. Data were analyzed using three-way ANOVA and Bonferroni post-hoc test (α=0.05). Results: The Single Bond Universal group in SE mode with light-cure composite yielded the highest (39.24MPa), and the G-Premio SE group with dual-cure composite produced the lowest (13.65MPa) mean µTBS (P<0.05). The dominant failure mode was adhesive, in all groups. Conclusion: The bonding agent had a significant effect on µTBS of composite to dentin, but different composites and different etching modes were not significantly different in this respect.

The comparison of the repair bond strength of the composite resin to direct and indirect composite restorations with different surface preparations.

Indirect restorations have been employed in restorative dentistry to solve some of the drawbacks of direct restorations. The aim of this study was to evaluate the effect of different modes of a universal adhesive resin on the repair capacity of two indirect resin composites and a direct resin composite. Indirect composite resins (Ceramage and Gradia Plus) and a direct composite resin (Filtek Z250) were prepared in a plastic mold with a height and diameter of 2-mm and 6-mm, respectively. Composite blocks were thermocycled (5000 cycles, 5°C-55°C). Then, according to their surface treatments, composite blocks were categorized into six-groups: Group 1: ER (etch&rinse), Group 2: SE (self-etch), Group 3: Bur+ER (bur+etch&rinse), Group 4: Bur+SE (bur+self-etch), Group 5: Bur+Silane+ER (bur+silane+etch&rinse), Group 6: Bur+Silane+SE (bur+silane+self-etch), respectively. After surface treatments and adhesive application for bonding with a direct resin composite, all groups were then thermocycled before performing shear-bond-strength-test. Failure modes were evaluated using a stereomicroscope. Data were analyzed by two-way-ANOVA and Bonferroni-test (P<0.05). The highest bond-strength values were obtained for Bur+Silane+SE groups, while the lowest values were obtained for the Bur+Silane+ER groups for all materials. Statistically significant differences were observed between the Bur+Silane+ER group and ER, Bur+ER and Bur+Silane+SE groups in Gradia Plus (P<0.05). The self-etch-mode of the universal-adhesive and silane applications led to the increase in the repair-strength of the adhesive in the Filtek Z250 and Ceramage. The self-etch-mode of the universal-adhesive might be used to reduce adhesive-application-steps in the clinical repair procedures.

Comparison between Shear Strength in Total Etch and Self Etch Adhesive material in Bonding of Stainless-steel Brackets

Bracket bonding in tooth enamel with total-etch material is a general practice procedure. The researchers combine etchant and bonding procedures in one application or called self-etch. This procedure is a solution for timesaving in bonding procedures and minimizing enamel damage without degrading the ability to sustain bond strength during the application of an orthodontic appliance. The aim of this research is to know the comparison between shear strength, ARI value, and enamel crack length between total-etch and self-etch adhesive material. Eighteenth teeth are divided into three groups which are K-1 as a control group without etchant application, K2 as the self-etch material group, and K-3 as the total etch material group. All teeth practiced shear strength test by Universal Testing Machine Autograph. After bracket removal, an Adhesive Remnant Index (ARI) test was performed and followed by cleaning the adhesive remnant with tungsten carbide burs and continued by enamel crack test by Scanning Electron Microscope (SEM). According to the OneWay Anova result, there is a difference between shear strength, ARI value, and significant enamel crack length (p&lt;0.05) between the control group, self-etch group, and total-etch group. Total etch material has higher shear strength, higher ARI value, and higher enamel crack length number than self-etch material.

Evaluation of gap formation for different adhesive agents in primary teeth with optical coherence tomography.

This study aimed to evaluate gap formation between the tooth surface and restorative material in terms of microleakage by using optical coherence tomography (OCT) for self-etch and selective-etch applications of two different universal and one self-etch adhesives. Sixty non-caries, primary molar teeth were divided into six groups; self-etch and selective-etch application ways of two different universal and one self-etch adhesive systems (n:10). After Class-V cavities were prepared, every tooth was distributed randomly in groups to apply adhesion procedure and then, all cavities were restored with polyacid-modified composite resin. Microleakage was evaluated by measuring the gap between the tooth surface and restoration by a blind researcher with Image J Software from OCT images. During statistical analysis, the significance level was accepted as p<0.05. According to the statistical analysis of the measurements obtained by Image J Software, selective-etch groups showed less gap formation than self-etch groups for each tested adhesive (p<0.05), and self-etch adhesive without etching showed significantly highest gap formation among all groups (p<0.05). Universal adhesives with a selective-etching step might be preferred over self-etch adhesives for long-lasting polyacid-modified composite resin restorations in primary teeth. However, obtained results should be considered with another prospective clinical study for long-term prognosis.

Evaluation of shear bond strength of orthodontic adhesives with integrated primer: A comparative study

Objectives: The study aimed to compare the shear bond strength (SBS) of three orthodontic adhesives with integrated primer, with those of self-etching and conventional bonding adhesives. Material and Methods: One hundred extracted premolars were randomly allocated to five groups. Brackets were bonded using three adhesives with integrated primer (GC Ortho Connect™, Biofix, and Orthocem). A group of brackets was bonded with the conventional bonding procedure (Transbond XT) and one group was bonded with a self-etching primer (Transbond™ Plus). All samples were subjected to thermal aging (5000 cycles: At 5°C and 55°C media). The compressive strength test was performed and the maximum load when the bracket detached was recorded. The amount of residual adhesive (ARI) remaining on the tooth surface was assessed visually. Results: Significantly higher SBS values were recorded with the conventional technique (14.01 ± 5.79 megapascals [MPa]), compared to other groups except for GC Ortho Connect™ (11.86 ± 3.83 MPa). There was no significant difference between the self-etching group and the groups containing integrated primer samples. However, one of the adhesives with integrated primer presented SBS values near-slightly below the limit considered clinically successful (7.65 ± 3.71 MPa). The ARI scores varied between adhesive groups; GC Ortho Connect™ and the self-etching primer samples showed statistically significantly higher scores compared to the three other groups. Conclusion: Clinically successful bonding values were achieved with two out of three different adhesives with integrated primer. One of the adhesives with integrated primer provided a similar SBS value to the tri-step conventional bonding procedure. ARI scores varied independently from SBS values.

Effect of Different Mouthwashing Regimens on Adhesion of a Universal Adhesive:A Microshear Bond Strength and Scaning Electron Microscopy Evaluation

Objective: To evaluate the effect of probiotic or chlorhexidine-based mouthwashes and coconut oil pulling therapy on microshear bond strength of a universal adhesive, used with two application modes. Method: Ninety-six enamel specimens were prepared using bovine incisors and the surfaces were grounded. Then the specimens were randomly divided into 4groups and each group were subjected to a mouth washing regimen with one of three agents-chlorhexidine mouthwash, probiotic-based mouthwash, coconut oil pulling – or stored in artificial saliva(control) for 7 days(n=24). After the procedure, all groups were divided into 2 subgroups, and a universal adhesive was applied with etch-and-rinse or self-etch mode(n=12). Composite micro-cylinders were bonded to the enamel surfaces and micro-shear-bond strength was measured after 24hours water storage. Failure modes were determined using a stereomicroscope and SEM analysis was also performed. The data were analyzed using Mann-Whitney-U and Kruskal-Wallis tests. Results: No significant differences were observed between the different mouthwash groups, regardless of application modes(p&gt; .05). There were no significant differences in microshear-bond strength, within the same mouthwash groups, between self-etch or etch-and-rinse modes, except for oil pulling group. Etch-and-rinse group showed higher bond strength than self-etch group in specimens subjected to oil pulling(p&lt; .05). Conclusion: Etch-and-rinse mode might be preferable on patients who practice oil pulling.

Universal Simplified Adhesive applied under different bonding technique's: 36-month Randomized Multicentre Clinical Trial

To evaluate the clinical performance of a new dual-cure universal adhesive system (Futurabond U, Voco) when applied using different application strategies in non-carious cervical lesions (NCCLs) after 36 months. Futurabond U was applied in NCCLs of 50 subjects using four adhesion strategies (n=50 restorations per group): only self-etch (SEE); selective enamel etching+self-etch (SET); etch-and-rinse with dry dentin (ERDry); and etch-and-rinse with wet dentin (ERWet). All cavities were restored using Admira Fusion composite resin (Voco). Restorations were evaluated after 36 months using the World Federation criteria (FDI) and the modified United States Public Health Service (USPHS) criteria. The after 36-month retention rates were 87% (75-92%) for SEE, 94% (83-98%) for SET, 91% (80-97%) for ERDry, and 94% (83-98%) for ERWet. Forty-three restorations were considered to have minor discrepancies in marginal adaptation at the 36-month recall (18 for SEE, 12 for SET, 7 for ERDry, and 6 for ERWet; p > 0.05). One restoration was detected as a minor marginal discoloration at the 36-month recall (1 for SET; p > 0.05). No restorations showed postoperative sensitivity and caries recurrence at 36 months. The clinical performance of the Futurabond U did not depend on the employed bonding strategy, and it was considered reliable after 36 months of clinical evaluation. However, greater marginal discrepancy was observed in the self-etch groups. NCCLs restorations using a dual-cure universal adhesive in self-etch and etch-and-rinse modes showed satisfactory clinical performance after 36 months.

Compressive strength, surface roughness, and surface microhardness of principle tricalcium silicate-based endodontic cements after universal adhesive application.

It was aimed to evaluate compressive strength (CS), surface roughness, and microhardness of mineral trioxide aggregate (ProRoot MTA) and Biodentine (BD) after adhesive application. Tests was carried out according to international ISO standard. ProRoot MTA and BD were prepared in Teflon molds according to manufacturer's instructions: n = 210 for CS; n = 210 for microhardness. Samples were incubated for 7 days at 37°C in 100% humidity. Surfaces were smoothed with up to 2000 grits of silicon-carbide sandpaper on abrasive device at 150 rpm, randomly divided into seven groups (n = 15). Clearfil Universal Bond, All Bond Universal, and Single Bond Universal (SBU) were applied in both total-etch and self-etch (SE) modes. Adhesives were applied according to manufacturers' recommendations (no adhesive used in control). CS was performed at speed of 1 mm/min, microhardness at 100 gr for 15 s. The surface roughness of the samples was analyzed with atomic force microscopy. Two-way analysis of variance and post hoc Tukey tests were used for the evaluation of the data. Man CS and microhardness values between ProRoot MTA and BD were as follows: 24.9 N, 72.6 HV; 59.8 N, 59.0 HV, respectively. In CS, BD was higher than ProRoot MTA (P < 0.05). In other comparisons except for SBU SE group (P < 0.05), BD and ProRoot MTA showed similar results (P > 0.05). However, ProRoot MTA was found higher than BD regarding microhardness (P < 0.05). As a result of the adhesive application in both BD and ProRoot MTA groups, a decrease in surface roughness was observed compared to the control group. BD exhibited better results than ProRoot MTA regarding CS. However, ProRoot MTA was found to be more successful than BD in terms of microhardness. BD and ProRoot MTA showed similar physical properties in terms of surface roughness. To improve regenerative procedures, besides the selection of bioceramic cements, the interaction between cements and materials applied during coronal restoration should be considered.

Effect of antimicrobial photodynamic therapy with different photosensitizers and adhesion protocol on the bond strength of resin composite to sound dentin.

The aim of this study is to evaluate the influence of the antimicrobial photodynamic therapy with phycocyanin and toluidine blue on the bond strength of resin composite to the sound dentin. The samples include 120 tooth blocks taken from 60 human extracted sound third molar teeth. They were randomly divided into 12 groups and disinfected with two different photosensitizers (Phycocyanin and Toluidine blue) activated by 635 nm diode laser for aPDT procedure. Then two different protocols (total-etch and self-etch) of universal adhesive system (G-Premio BOND, GC Dental Products CORP. Japan) were applied. The samples then filled with resin composite (Gradia® Direct, GC Dental Products CORP. Japan). After 10000 cycles of thermocycling, all samples were subjected to the micro shear bond strength (μSBS) test using a universal testing machine (1 mm/min). The data were analyzed with One Way ANOVA. The effect of aPDT using both photosensitizers (phycocyanin and toluidine blue O) on the bonding strength to dentin was not significant (P>0.05). However, the bonding strength of total etch groups was reduced significantly (P<0.05) after aPDT using both photosensitizers. Phycocyanin self-etch group showed the greatest bonding strength (19.48 ± 3.89 MPa) in comparison to other aPDT groups. No significant reduction after thermocycling in dentin bond strength was observed in all groups (P>0.05), with exception of control total etch groups, which showed significant difference (P<0.05). aPDT using toluidine blue O and phycocyanin has no adverse effect on bonding to sound dentin when using universal adhesive in self-etch protocol. Phycocyanin is more recommended to be used in aPDT in comparison to toluidine blue as a natural photosensitizer.

Orthodontic bond strength with the use of non-aerosol producing bonding primers in lieu of conventional primers: An in vitro evaluation.

To evaluate the efficacy of non-aerosol producing restorative self-etching primers (SEPs) as a substitute for conventional orthodontic bonding primers and to analyze the extent of residual composite on the tooth post-debonding. Eighty-four extracted human premolars were randomly divided into seven groups based on the adhesive and the bonding protocol used. The study comprised Prime and Bond one select (Dentsply), G-Premio Bond (GC), which were each divided into three subgroups based on the method used for moisture control and the control group (Transbond XT conventional total etch). The three methods for moisture control in study groups were: without drying, air-drying with the use of a three-way syringe, and with the use of blotting paper. Shear bond strength (SBS) was tested using a universal testing machine (UTM), and after debonding, the enamel surface of each tooth was examined under 10× magnification to evaluate adhesive remaining index (ARI) scores. Groups 2A (Prime and Bond; without drying) & 1 (Transbond XT) had the lowest and highest SBS values, respectively (P = 0.001). Comparison of ARI between the control group and group 2b (Prime and Bond; air-drying with 3 in 1) showed a significant difference (P = 0.041). Comparison of ARI between control group and group 2c (Prime and Bond; blotting paper) showed a significant difference (P = 0.017). Rest all other comparisons were non-significant. Transbond XT had SBS values higher than the self-etch groups. Among the self-etch groups, G-Premio Bond had higher SBS values when the traditional methods of air-drying were followed. Use of blotting paper for drying that produced variable SBS values can be an effective alternative method. G-Premio Bond with its adequate bond strength under manufacturer's instruction seems promising in this regard.

Comparative evaluation of different adhesive strategies of a universal adhesive in class II bulk-fill restorations: A 48-month randomized controlled trial

ObjectivesTo compare the clinical performance of the universal adhesive used in etch-and-rinse (ER) and self-etch (SE) adhesive strategies for 48-month in class II bulk-fill restorations. MethodsA total of 84 class II bulk-fill resin composite (Tetric EvoCeram Bulk Fill) restorations were placed in 35 participants by one operator using the universal adhesive's (Adhese Universal VivaPen) etch-and-rinse or self-etch mode randomly. The restorations were evaluated by two calibrated examiners at baseline and after 6-, 12-, 24-, 36- and 48-month using modified USPHS criteria. The comparison of the two adhesive strategies for each evaluation criteria was performed with the chi-square test. The baseline scores were compared with those at the recalls using the Friedman and Cochran's Q-test (p < .05). ResultsAt 48-month, 74 restorations were evaluated in 30 participants (recall rate: 85.7%). Marginal discoloration was statistically more frequent in SE approach (p < .05), whereas no significant difference was observed between the two strategies in terms of marginal adaptation (p > .05). There were statistically significant differences between the baseline and 48-month recall in the SE group in terms of marginal adaptation and discoloration (p < .05). In ER group, significant differences were found between baseline and 48-month only for marginal adaptation (p < .05). None of the restorations showed post-operative sensitivity. Secondary caries was observed in one restoration from SE group. ConclusionsThe tested bulk-fill restorative exhibited better clinical performance only in terms of marginal discoloration when the universal adhesive was used with ER strategy. Clinical relevanceThough ER approach of the tested universal adhesive appears to be advantageous in terms of marginal discoloration, both adhesive strategies had similar impact on the clinical success of bulk-fill resin restorations.

The effect of etching techniques on cement penetration into dentinal tubules on fiber post cementation

ObjectiveA combination of self-etch and additional etch techniques as pre-cementation procedures for fiber post restoration was reported able to increase the bonding of adhesive material. This research aimed to determine the effects of different etching techniques on resin cement penetration into dentinal tubules. Materials and methodsThirty-two endodontic treated premolars were prepared for 10 mm fiber posts and were divided into two groups (n = 16). Group one was treated with self-etch only, and the second was treated with a combination of self-etch and additional etching. The fiber posts were cemented using fluorescent rhodamine B 0.1%-colored resin cement. The samples were cut to a 2 mm thickness in the middle third of the root and were evaluated with confocal laser scanning microscopy (CLSM). Statistical analysis measurements were analyzed by an independent t-test and Pearson correlation test. ResultsThere were statistically different in densities hybrid layer and resin tag penetration lengths. Statistically strong linear positive correlations between the hybrid layer density and resin tag penetration length in both groups were also observed. Hybrid layer density (9.68 μm), resin tag penetration depth (32.51 μm) in the self-etch group with additional etching were higher than in the other group. The Pearson correlation test results between hybrid bond density and resin tag penetration depth in the self-etch treatment group showed a value of r = 0.634 and p-value = 0.008 and in the etching group self-treatment with additional etching a value of r = 0.516 and p-value = 0.041 (p ≤ 0.05). ConclusionThere is a statistically significant positive correlation or linear relationship between hybrid bond density and the penetration depth of resin tags in both treatment groups: the thicker the hybrid layer density, the deeper the penetration of the resin tags. This phenomenon may increase mechanical strength regarding stronger binding of resin cement to a tooth’s substrate.

Dentin surface and hybrid layer morphological analysis after use of a copaiba oil- based dentin biomodifier

This study evaluated dentin surface and hybrid layer’s morphology, using copaíba (CO) emulsion as dentin biomodifier before traditional and self-etching adhesive, by environmental scanning electron microscopy (ESEM). Ninety-six third sound molars were divided into 16 groups, according to the dentin substrate, tested substances, and the adhesive system used. The conditioned dentin surface treated with clorexidina (CHX) 2% showed phosphate salts on two dentin substrates as well as the sound conditioned or not surface treated with calcium hydroxide solution (CHS), where the mineral precipitate deposition obstructs the tubules lumen. A significant difference (p &lt;0.0001) in dentin surface morphology was observed at the CHS group on conditioned and not conditioned sound dentin. The CO emulsion produced a regular and homogenous hybrid layer with many resin tags on both dentin surfaces, irrespective of the adhesive system used, with better performance than CHS and CHX 2% (p =0.0007) on caries-affected dentin at the self-etching group. CO emulsion showed no morphological changes on sound and caries-affected dentin and presented a regular hybrid layer, regardless of the adhesive system used.&#x0D; Keywords: Copaiba oleoresin; Emulsions; Dentin-bonding agents; Phytotherapy.

24-Month Clinical Performance of a Universal Adhesive on Non-Carious Cervical Lesions: Self-Etch and Etch-and-Rinse Techniques.

To evaluate the 24-month clinical performance of Adhese Universal (ADH) (Ivoclar Vivadent) using two different application modes (etch-and-rinse vs self-etch) when restoring non-carious cervical lesions. Twenty-six patients participated in this study. A total of 117 non-carious cervical lesion restorations (N = 117) were assigned to two groups: 1) ADH in the etch-and-rinse mode (n = 59) and 2) ADH in the self-etch mode (n = 58). The same resin composite (Tetric EvoCeram, Ivoclar Vivadent) was used for all restorations. The restorations were evaluated at baseline and at 24 months using the World Dental Federation (FDI) criteria. The results were analyzed statistically using the McNemar test (α = 0.05) and a generalized estimating equation. In self-etch mode, significant differences were found for marginal coloring (p = 0.002), marginal adaptation (p = 0.031), and hypersensitivity (p = 0.031) between baseline and the end of the 24-month period. In the etch-and-rinse mode, significant differences were found for marginal coloring (p = 0.004), fractures/retention (p = 0.002), marginal adaptation (p = 0.002), and hypersensitivity (p = 0.000). Significant differences were also detected between groups at 24 months for fractures/retention (p = 0.001). At 24 months, 10 restorations of the etch-and-rinse group were lost and 2 restorations of the self-etch group were lost. In terms of fractures and retention criteria, this universal adhesive obtained better results when applied in self-etch mode than in etch-and-rinse mode.

Phenolic extract of Libidibia ferrea inhibits dentin endogenous enzymatic activity depending on the adhesive system strategy

This study evaluated the influence of Libidibia ferrea (Lf) extract used as dentin pretreatment on the resin-dentin bond strength stability and dentin endogenous enzymatic activity. The phytochemical profile (PP) of the Lf extract was evaluated by liquid chromatography; particle size, polydispersity index (PdI), and zeta potential (ZP) were evaluated by dynamic light scattering. The tested groups were ER-Scotchbond Universal (SBU) in the etch-and-rinse (ER) mode; ERLf-SBU in the ER mode + Lf after etching; SE- SBU in the self-etch (SE) mode; and LfSE-Lf before SBU in the SE mode. Sticks were obtained for microtensile bond strength tests and failure mode (24 hr and 12 months). The hybrid layer was evaluated using scanning electron microscopy. The endogenous enzymatic activity of the underlying dentin was analyzed by in situ zymography with the same treatments. The PP showed the presence of quercetin (2.6% w/w). Lf particles were considered large after the analysis of the PdI. The ZP remained stable over time. The ER and ERLf groups had lower bond strength after 12 months, but SE and LfSE remained stable. The predominant failure mode was adhesive for both times. ER and ERLf had longer resin tags and a thicker hybrid layer. The ER and LfSE groups showed higher enzymatic activity than the ERLf and SE groups after 12 months. The Lf extract may contribute to inhibit the dentin endogenous enzymatic activity when associated with an adhesive system in the ER mode.