Prompt L-Pop Research Articles

Bond strength of self-etch adhesives to dentin prepared with three different diamond burs

Objectives To evaluate the micro-tensile bond strength (μTBS) of a control etch-and-rinse and three self-etch (strong, mild, ultra-mild) adhesive systems to dentin prepared with three different grit size of diamond burs. Methods Dentin surfaces were created from mid-coronal sound dentin in extracted, human third molars. The teeth were ground with high-speed medium grit (100 μm), fine grit (30 μm), or extra-fine grit (15 μm) diamond bur. Resin composite (Z100) was bonded to the surfaces using Optibond FL, Adper Prompt L-Pop, Clearfil SE Bond, or Clearfil S3 Bond. Rectangular micro-specimens were prepared using the slow-speed diamond saw and tested in tensile to determine the μTBS. Failure analysis was performed using a stereo-microscope and Fe-SEM. Data were analyzed by two-way analysis of variance and Tukey's HSD test ( p < 0.05). Results The etch-and-rinse adhesive yielded high micro-tensile values (58–69 MPa), irrespective of the diamond burs used. The bond strength values were comparable for Adper Prompt L-Pop and Clearfil SE Bond irrespective of the burs used. The μTBS values were significantly higher as the particle size of diamond burs is smaller for Clearfil S3 Bond. Most failures were recorded as interfacial failure when the fine and extra-fine diamond burs were used. Significance Overall, different grit-sized diamond burs did not affect the mechanical properties of the interface, except for the ultra-mild one step self-etch adhesive. This adhesive performed significantly better when a smaller grit size was used to prepare dentin surface.

Microtensile Dentin and Enamel Bond Strengths of Recent Self-etching Resins

In this study, the microtensile bond strengths of resin composites to dentin and enamel produced by recently introduced self-etching resins were determined. Included were two adhesives with self-etching primers, Clearfil SE (Kuraray) and Peak SE (Ultradent), four self-etching adhesives, Optibond All-In-One (Kerr), Clearfil S3 (Kuraray), Adper Prompt L-Pop (3M ESPE) and iBond (Heraeus Kulzer) and, as a positive control, PQ1 (Ultradent), an etch-and-rinse adhesive. Each product was evaluated using the same hybrid resin composite, Z250 (3M ESPE). Testing was performed after 48 hours using a "non-trimming" microtensile test at a crosshead speed of 0.6 mm/minute. Sample size was five teeth per group, with the value for each tooth calculated by averaging the bond strengths of seven beams derived from it. Mean values in MPa (SD) for dentin were: Clearfil SE 81.6 (3.5),a Peak SE 80.3 (9.9),a PQ1 73.4 (4.9),a,b Optibond All-In-One 64.4 (5.9),b Clearfil S3 62.5 (2.2),b,c iBond 51.0 (4.0)c and Prompt L-Pop 33.9 (6.4).d Mean values in MPa (SD) for enamel were: PQ1 55.6 (2.5),a Clearfil SE 54.1 (5.4),a Prompt L-Pop 54.0 (5.4),a Peak SE 51.8 (1.5),a,b Clearfil S3 44.3 (5.2),b,c Optibond All-In-One 40.1 (2.1)c,d and iBond 33.8 (3.3).d (Values for each substrate with the same letter were not significantly different, one-way ANOVA, Tukey-Kramer Multiple Comparison Test, p<0.05.) Compared to the positive control, PQ1, only adhesives with self-etching primers, Clearfil SE and Peak SE, were as effective in bonding to both enamel and dentin. With the exception of Prompt L-Pop, scanning electron micrographs of the etched enamel surface produced by self-etching products indicated far less surface topography than conventional etching, even for self-etching primer systems producing the same bond strengths as the etch-and-rinse adhesive.

Clinical Evaluation of a Resin-based Desensitizing Agent and Self-etching Adhesive on Reduction of Postoperative Sensitivity of Amalgam Restorations

The aim of this randomized, double blind clinical trial was to compare three lining materials (Adper Prompt L-Pop, VivaSens, and Copalite) versus unlined restorations on postoperative cold sensitivity of class I amalgam restorations. Potential subjects were screened for the presence of four initial class I carious lesions on posterior teeth. Each tooth was assigned to treatments according to a randomized block design. After cavity preparation, teeth were lined with either VivaSens, Adper Prompt L-Pop, or Copalite, and one tooth remained unlined and served as a control. The cavities were filled with high copper amalgam (Oralloy). The time taken for a subject to respond to a standardized cold stimulus (CRM) was recorded at baseline, 24 hours, one week, and one month after treatment. Participants filled out a self-report questionnaire at each time point. Data was gathered by analysis of variance (ANOVA) and Duncan Multiple Comparisons tests (alpha=0.05). Twenty subjects participated in this study. Comparisons within each group found no significant reduction in mean CRM for the Adper Prompt L-Pop group (P>0.05), but a significant difference in mean CRM for the VivaSens group was observed at one week and one month intervals after restoration (P<0.05). Copalite and the unlined groups showed significant mean CRM reductions after one day (P<0.05). No significant differences between groups receiving Adper Prompt L-Pop and Copalite were found at any time point (P>0.05). VivaSens showed more cold sensitivity than Adper Prompt L-Pop at one week and one month recalls (P<0.05), while the most cold sensitivity was found in the unlined group. Adper Prompt L-Pop and Copalite reduced postoperative sensitivity to cold more than VivaSens and unlined groups at all assessment time points, 24 hours, one week, and one-month post treatment. The subjects receiving Copalite, VivaSens, and unlined restorations experienced greater sensitivity to cold at one month compared to baseline, while subjects receiving the Adper Prompt L-Pop liner experienced no greater sensitivity to cold from baseline to one month. Adper Prompt L-Pop as a liner under spherical high copper amalgam successfully reduced cold postoperative sensitivity.

The resistence of conditioned enamel to the effect of cariogenic solution

Enamel surface around restoration is very sensitive to the effect of cariogenic solution. It is the consequence of the manner the cavity is prepared before restoration, the existence of marginal cracks around restoration, that is, irregular polishing of filling. The aim of this study is to analyze the morphology of the marginal enamel surface around composite fifth class restoration after the application of cariogenic solution. In this study 28 extracted molars were used. After the V class preparation of the buccal crown surface, teeth samples were divided into two groups. The first group was restored with the composite system Single Bond +Z250, applying the total etching technique. The second group was restorated with Prompt L-pop +Z250 and by applying self-etching primers. After the cavity restoration, teeth samples were kept in demineralising solution (lactic acid, pH 4.5, 0.1 M) at the temperature of 37 degrees C during 7 and 28 days. Control group samples were kept in distilled water during the experiment. The marginal enamel surface analysis was done by a scanning electron microscope. The achieved results showed that there was a denivelation and severe demineralization of the perimarginal enamel zone after 7 and 28 days, while on the remaining enamel there were some minor changes. Along the marginal composite/enamel joint there was the central type of demineralization of enamel prisms and preserved inter prismatic enamel.The existence of pores of different sizes and scattered enamel fractures was established. The marginal joint was mostly without any gaps in the first group samples, while in the second group samples there were narrow or wider edge gaps. After the application ofcariogenic solution, perimarrginal enamel showed conspicuous morphological damage in comparison to the remaining enamel surface.

Influence of operator skill on microleakege of total-etch and self-etch bonding systems

Objectives To evaluate the influence of operator skill on microleakage in class V restorations using simplified bonding systems. Methods Two cavities were carried out on the buccal and lingual surfaces of 50 human bicuspid teeth. The teeth were randomly assigned to two groups according to the operator's skill: student group and expert group. The two cavities of each tooth were randomly treated with Adper Scotchbond 1 XT (total-etch adhesive) and Adper Prompt L-Pop (self-etch adhesive). All cavities were restored with a 0.2 mm thick layer of flowable composite (Filtek flow) followed by one bulk increment of resin composite (Filtek Supreme XT). Specimens were thermocycled, immersed in 2% methylene blue and sectioned in a bucco-lingual plane. They were then examined under a stereomicroscope and scored according to microleakage. The data was subjected to a multilevel statistical model. Results At the dentine margin the microleakage resulting from both the self-etch adhesive and the total-etch one was similar in the student and in the expert groups. The interaction term skill × adhesive was not statistically significant ( p = 0.4156). At the enamel margin the self-etch adhesive microleakage within the student group resulted lower than that within the expert group. On the other hand, the total-etch adhesive microleakage within the expert group resulted lower than that within the student group. The interaction term skill × adhesive was statistically significant ( p = 0.0037). Conclusions Both the adhesives used were sensitive to operator skill in obtaining a reliable seal with the enamel. On the dentine, both adhesives demonstrated little sensitivity to operator skill.

Comparison of the Antibacterial Activity of Different Self-etching Primers and Adhesives

The aim of this study was to evaluate the antibacterial effects of different one-step and two-step self-etching primer/adhesives on Streptococcus mutans (S. mutans), Lactobacillus casei (L. casei), and Lactobacillus acidophilus (L. acidophilus). The antibacterial effects of Clearfil Protect Bond Primer and Bonding agent; AdheSE Primer and Bonding agent; Adper Prompt L-Pop; Futurabond NR; Clearfil Tri S Bond; and Cervitec (positive control, 1% chlorhexidine varnish) were tested against standard strains of S. mutans, L. Casei, and L. acidophilus using the disk diffusion method. Standard filter paper disks (n=5) impregnated with 20 microL of each material were prepared. After incubation at 37 masculineC for 48 hours in a 5-10% CO2 atmosphere, the diameter of inhibition zones were measured in millimeters. Data were analyzed using one way analysis of variance (ANOVA) and multivariate analysis of variance (MANOVA). Duncan's Multiple Range Test was used for pairwise comparison. The size of inhibition zones produced by primer/adhesives varied among the brands. AdheSE Primer: S. mutans (20.6+/-1.51); L. casei (14.8+/-1.78); L. acidophilus (11.4+/-0.54). Adper Prompt L-Pop: S. mutans (19.6+/-1.51); L. casei (13.8+/-1.64); L. acidophilus (13.8+/-1.09). Cervitec: S. mutans (23+/-0.00); L. casei (27+/-0.70); L. acidophilus (22.4+/-0.54). Clearfil Protect Bond Primer: S. mutans (17+/-0.00); L. casei (17.6+/-0.54); L. acidophilus (22.4+/-0.54). Futurabond NR was found effective only against S. mutans (14.6+/-1.67). Of all the materials tested, AdheSE Bonding agent, Clearfil Protect Bond Bonding agent, and Clearfil Tri S Bond exhibited no inhibition zone (-) for all bacteria tested. Among the adhesives tested Clearafil Protect Bond Primer based upon monomer methacryloyloxydodecylpyridiniium bromide (MDPB) was found to be the most potent material against L. acidophilus and L. casei. AdheSE Primer and Adper Prompt L-Pop are highly effective against S. mutans. Compared with other adhesive systems, Clearfil Protect Bond Primer (containing MDPB) showed a high antibacterial effect against all microorganizms tested. Two-step, self-etching primer/adhesive system Clearfil Protect Bond might be a suitable choice under minimally invasive restorations. The recently developed one-step, self-etching system Clearfil Tri S Bond showed no antibacterial effect against microorgazims tested.

Adhesion of a self‐etching system to dental substrate prepared by Er:YAG laser or air abrasion

The purpose of this study was to assess the microtensile bond strength of a self-etching adhesive system to enamel and dentin prepared by Er:YAG laser irradiation or air abrasion, as well as to evaluate the adhesive interfaces by scanning electron microscopy (SEM). For microtensile bond strength test, 80 third molars were randomly assigned to five groups: Group I, carbide bur, control (CB); II, air abrasion with standard tip (ST); III, air abrasion with supersonic tip (SP); IV, Er:YAG laser 250 mJ/4 Hz (L250); V, Er:YAG laser 300 mJ/4 Hz (L300). Each group was divided into two subgroups (n = 8) (enamel, E and dentin, D). E and D surfaces were treated with the self-etching system Adper Prompt L-Pop and composite buildups were done with Filtek Z-250. Sticks with a cross-sectional area of 0.8 mm(2) (+/-0.2 mm(2)) were obtained and the bond strength tests were performed. Data were submitted to ANOVA and Tukey's test. For morphological analysis, disks of 30 third molars were restored, sectioned and prepared for SEM. Dentin presented the highest values of adhesion, differing from enamel. Laser and air-abrasion preparations were similar to enamel. Dentin air-abrasion with standard tip group showed higher bond strength results than Er:YAG-laser groups, however, air-abrasion and Er:YAG laser groups were similar to control group. SEM micrographs revealed that, for both enamel and dentin, the air-abrasion and laser preparations presented irregular adhesive interfaces, different from the ones prepared by rotary instrument. It was concluded that cavity preparations accomplished by both Er:YAG laser energies and air abrasion tips did not positively influence the adhesion to enamel and dentin.

Bond strength of adhesive systems to dentin and enamel—Human vs. bovine primary teeth in vitro

Objectives This in vitro study compared the bonding performance of four adhesive luting agents to dentin and enamel of human and bovine primary teeth, in order to evaluate the suitability of primary bovine hard tissues for replacement of those of human origin for bond testing. Methods A composite (Clearfil AP-X) was bonded to specimens from 167 extracted human ( n = 88) and bovine ( n = 88) primary teeth using the following adhesive systems: Syntac Assortment (SY), Adaper Prompt L-Pop (PLP), iBond Gluma inside (IB) and Clearfil Protect Bond (PB). After 24 h storage in distilled water, shear bond strength was determined according to ISO/TS 11405:2003. The data ( n = 11 per group) were statistically analyzed with the Mann–Whitney U-test and the error-rates method (ERM). The fracture modes were analyzed with the χ 2-test. Results Bond strength data (ERM) and fracture modes ( χ 2-test) using human primary teeth were, in general, not statistically different from those of bovine origin. With few exceptions, pair wise comparisons showed the same results. The bond strength data for SY, PLP and PB bonded to primary human and bovine enamel were higher than those to primary human and bovine dentin, for IB vice versa. Significance Bovine teeth may be considered as a suitable alternative to human teeth in bond strength tests for primary dentition.

Microtensile Bond Strength of Contemporary Adhesives to Primary Enamel and Dentin

The purpose of this study was to assess bond strength of three self-etching and two total-etch adhesive systems bonded to primary tooth enamel and dentin. Forty extracted primary human molars were selected and abraded in order to create flat buccal enamel and occlusal dentin surfaces. Teeth were assigned to one of the adhesive systems: Adper Scotch Bond Multi Purpose, Adper Single Bond 2, Adper Prompt L-Pop, Clearfil SE Bond and AdheSE. Immediately to adhesive application, a composite resin (Filtek Z250) block was built up. After 3 months of water storage, each sample was sequentially sectioned in order to obtain sticks with a square cross-sectional area of about 0.72 mm2. The specimens were fixed lengthways to a microtensile device and tested using a universal testing machine with a 50-N load cell at a crosshead speed of 0.5 mm/min. Microtensile bond strength values were recorded in MPa and compared by Analysis of Variance and the post hoc Tukey test (a = 0.05). In enamel, Clearfil SE Bond presented the highest values, followed by Adper Single Bond 2, AdheSE and Adper Scotch Bond Multi Purpose, without significant difference. The highest values in dentin were obtained with Adper Scotch Bond Multi Purpose and all other adhesives did not present significant different values from that, except Adper Prompt L-Pop that achieved the lowest bond strength in both substrates. Adper Scotch Bond Multi Purpose and Adper Single Bond 2 presented significantly lower values in enamel than in dentin although all other adhesives presented similar results in both substrates. contemporary adhesive systems present similar behaviors when bonded to primary teeth, with the exception of the one-step self-etching system; and self-etching systems can achieve bond strength values as good in enamel as in dentin of primary teeth.

Dentin diffusion of HEMA released from etch‐and‐rinse and self‐etch bonding systems

The aim of this in vitro study was to determine the diffusion of 2-hydroxyethyl methacrylate (HEMA) released from different bonding systems (BS) through dentin. Occlusal cavities with a remaining dentin thickness (RDT) of 0.5 mm (n=90) and 0.25 mm (n=80), respectively, were prepared in dentin discs of non-carious human molars. Artificial pulp chambers were attached to the pulpal side of each dentin disc. Bonding systems were applied with (Clearfil SE Bond, OptiBond FL, OptiBond Solo Plus) or without (AdheSE, Adper Prompt L-Pop, Clearfil SE Bond, OptiBond FL, OptiBond Solo Plus Self Etch, Xeno III) prior phosphoric acid etching. HEMA was detected by gas chromatography/mass spectrometry (n=10 per BS and RDT). The highest mean HEMA concentration was found in the 0.25 mm RDT group treated with OptiBond FL (13.3 microg) and the lowest mean HEMA concentration was detected in the 0.5 mm RDT group treated with AdheSE (0.5 microg). At 0.25 mm RDT the quantities of HEMA recovered in the artificial pulp chambers were significantly higher than at 0.5 mm RDT, except for Clearfil SE Bond. Etching with phosphoric acid increased the detected HEMA quantities compared with self-etch BS. In deep cavity preparations, etching with phosphoric acid should be avoided in favor of the use of self-etch BS.

Shear Bond Strength of Different Adhesive Systems to Primary Dentin and Enamel

The aims of this study were to evaluate the shear bond strength (SBS) off our adhesive systenms applied to primary dentin and enamel and verify, after SBS testing, the failure mode of the adhesive interface. Sixty extracted sound primary molars were selected and crowns were sectioned in a mesial-distal direction. Specimens were randomly assigned into two groups (adhesion to enamel and adhesion to dentin) and then subdivided into four subgroups according to the adhesive system (n=15). Scotchbond Multi-Purpose (SMP)--Single Bond (SB)--Clearfil SE Bond (and Adper Prompt L-Pop (APL)--SBS tests were performed and the obtained values were statistically analyzed using ANOVA and Tukey tests (p < 0.05). The failure mode analysis was performed with a Scanning Electron Microscope (XL-30, Philips). SBS mean values on enamel were [MPa (SD)]: SMP--2789 (749); SB--23.92 (8.8); CSB--24.36 (6.69), APL--25.96 (4.08); and on dentin: SMP--17.29 (4.25) SB--18.2 (8.74); CSB--16.13 (714); APL--6. 04 (3.35). The predominant failure mode was cohesive (primarily of the bonding agent). On enamel SBS was statistically similar for all four adhesives. On dentin SBS ofAPL was lower than the other tested adhesives.

Influence of dentin cavity surface finishing on micro-tensile bond strength of adhesives

The current trend toward minimal-invasive dentistry has introduced innovative techniques for cavity preparation. Chemical vapor deposition (CVD) and laser-irradiation technology have been employed as an alternative to the common use of regular burs in high-speed turbines. Objectives The purpose of this study was to assess the influence of alternative techniques for cavity preparation on the bonding effectiveness of different adhesives to dentin, and to evaluate the morphological characteristics of dentin prepared with those techniques. Methods One etch&rinse adhesive (OptiBond FL, Kerr) and three self-etch systems (Adper Prompt L-Pop, 3M ESPE; Clearfil SE Bond, Kuraray; Clearfil S3 Bond, Kuraray) were applied on dentin prepared with a regular bur in a turbine, with a CVD bur in a turbine, with a CVD tip in ultrasound and with an Er,Cr:YSGG laser. The micro-tensile bond strength (μTBS) was determined after storage in water for 24 h at 37 °C, and morphological evaluation was performed by means of field-emission-gun scanning electron microscopy (Feg-SEM). Results Feg-SEM evaluation revealed different morphological features on the dentin surface after the usage of both the conventional and alternative techniques for cavity preparation, more specifically regarding smear-layer thickness and surface roughness. CVD bur-cut, CVD ultra-sonoabraded and laser-irradiated dentin resulted in lower μTBSs than conventionally bur-cut dentin, irrespective of the adhesive employed. Significance The techniques, such as CVD diamond-bur cutting, CVD diamond ultra-sonoabrasion and laser-irradiation, used for cavity preparation may affect the bonding effectiveness of adhesives to dentin, irrespective of their acidity or approach.

Marginal integrity of class V restorations: SEM versus dye penetration

Objectives To perform an in vitro investigation on the marginal integrity of different adhesives (Optibond FL, Scotchbond 1XT, Clearfil SE Bond, Adper Prompt L-Pop, S 3 Bond, iBond exp., Adper Prompt L-Pop) in combination with Tetric Ceram as well as an experimental silorane-restorative (Hermes, Hermes Bond; 3M ESPE) using SEM and dye penetration (2% methylene blue) in a comparative manner. Methods Standardized class V-cavities (3 mm × 1.5 mm) were prepared in 70 extracted human teeth ( n = 10). The adhesives were applied according to manufacturers’ instructions. The cavities were restored with three increments. After finishing and polishing (Sof-Lex discs) and thermocycling (5000×, 5/55 °C), replicas were taken and the teeth immersed in the dye for 10 s (D10) and evaluated. After another penetration of 30 min (D30) a final evaluation of the percentage of dye-penetrated margins was conducted. Results The median percentages in marginal gaps (%) at the enamel margins for the three methods investigated (D10/D30/SEM) were—Optibond FL: 0/0/4, Scotchbond 1 XT: 5/16/11, Clearfil SE Bond: 0/0/0, S 3 Bond: 0/0/1, iBond exp.: 20/42/12, Adper Prompt L-Pop: 5/23/8, Hermes/Hermes Bond: 5/45/24. Cementum margins—Optibond FL: 0/1/0, Scotchbond 1 XT: 0/21/23, Clearfil SE Bond: 0/0/4, S 3 Bond: 0/0/0, iBond exp.: 0/0/0, Adper Prompt L-Pop: 10/32/23, Hermes/Hermes Bond: 0/0/13. After pooling the data of all groups, a Spearmann's ρ test showed a good correlation between the methods D10 and D30 at the enamel margins and at the entire cavity margins (correlation coefficient 0.8 and 0.7). Significance SEM did not correlate with the results obtained from D10 (correlation coefficient <0.5). A fair correlation was found between SEM and D30 for the entire cavity margin but a good correlation for the enamel margins. No correlation between investigation methods was determined at the cementum margins. D30 showed a better correlation to SEM than D10 did. Therefore, 30 min of dye penetration time seems to be more suitable than 10 s.

The induction of oxidative stress, cytotoxicity, and genotoxicity by dental adhesives

Objectives Polymerized dental resin materials release residual monomers that may interact with pulp tissues. We hypothesized that dental adhesives might cause cytotoxicity in pulp cells via the generation of reactive oxygen species (ROS), which may also contribute to genotoxic effects in vitro. Methods For cytotoxicity testing, transformed human pulp-derived cells were exposed to extracts of primers and bonding agents of Clearfil SE bond, Clearfil Protect bond, AdheSE, Prompt L-Pop, and Excite for 24 h. The cytotoxicity of the same materials was also analyzed in a dentin barrier test device using three-dimensional pulp cell cultures. The generation of ROS in monolayer cultures was measured after a 1 h exposure period by flow cytometry (FACS), and genotoxicity as indicated by the formation of micronuclei was determined in V79 cells after a 24 h exposure period. Results The dentin primers and bonding agents decrease cell survival in a dose-related manner. Cytotoxicity of bonding agents based on concentrations which caused 50% cell death (EC50) were ranked as follows: Excite (0.16 mg/ml) > AdheSE bond (0.30 mg/ml) > Clearfil Protect bond (0.35 mg/ml) > Clearfil SE bond (0.37 mg/ml), and Prompt L-Pop bond (0.68 mg/ml). Dentin primers were about 10-fold less effective. In contrast, no cytotoxic effects of the dental adhesives were observed in a dentin barrier test device. Yet, all dental adhesives increased the amounts of ROS about fivefold in pulp cells in a dose-related manner, and, again, the bonding agents were more efficient than the dentin primers. Finally, the number of micronuclei was increased about sixfold by extracts of the AdheSE primer. Significance Our results suggest that the cytotoxic potencies demonstrated by these materials might be of clinical relevance, since all dental adhesives disturbed the cellular redox state of pulp cells in monolayer cultures. As a result, the concentrations of biologically active ingredients of some of the agents may be high enough to modify pulp cell metabolism when the materials are used in deep cavities or directly contact pulp tissue.

Pulpal responses after application of current adhesive systems to deep cavities

The aim of the present study was to evaluate comparatively the pulpal tissue reactions of four adhesive systems placed in experimental cavities of healthy dog's teeth. Class V cavities with a mean value of remaining dentin thickness (RDT) ranging between 0.55 +/- 0.30-0.68 +/- 0.38 mm were prepared. The cavities were treated with the following adhesive systems: Etch and Prime 3.0 (EP), Single Bond (SB), Clearfil SE Bond (CSE), and Prompt L-Pop (PLP). The pulpal tissue responses to dentin adhesives were assessed histopathologically at postoperative periods of 7, 21, and 65 days, and the results were subjected to statistical analysis. A significantly greater adverse inflammatory response was observed with the materials EP and PLP, while a significantly lesser degree of disorganization in the odontoblastic zone was found with the materials SB and CSE, in the postoperative period of 65 days. In addition, a thicker predentin zone was observed where SB material was applied. Application of the selected adhesive systems to non-exposed cavities, with an RDT, which ranged between the above-mentioned rates, was correlated with slight to moderate inflammation and odontoblast reduction depending on the materials used as well as upon the RDT.

Effect of pre-etching enamel on fatigue of self-etch adhesive bonds

Objective A previous study found that the shear bond strength (SBS) to bovine enamel for the self-etching adhesive Adper Prompt-L-Pop (PLP) was 75% of that found with the etch-and-rinse material SingleBond, while the comparative value for the shear fatigue limit (SFL) was only 58% at 10 5 load cycles. Resin penetration into the enamel surface was substantially less for PLP but it was not conclusive that this was the reason for the lower results cited above. The objective of this study was to determine if pre-etching enamel would substantially improve the SBS and SFL of the PLP adhesive over those found in the previous study. Materials and methods All test methods were the same as for the previous study. SBS measurements were conducted for composite bonds to bovine enamel using a phosphoric acid pre-etch with the PLP adhesive (PLP-10) and for a conventional enamel-bonding adhesive (EB). Fatigue testing was done with the same test fixtures, load cycling at 2 Hz up to a maximum of 10 5 cycles at four selected peak load values between 35 and 60% of the respective bond strengths. Fatigue limits were determined from the data obtained. SEM analysis of resin penetration of the enamel surface was carried out for each adhesive. Results A significantly greater SBS and SFL were found for EB (SBS: 30.4 MPa; SFL: 15.6 MPa) than for PLP-10 (SBS: 20.2 MPa; SFL: 9.9 MPa). Compared with previously found results, the pre-etching of enamel had no significant improvement in SBS and only slight improvement in SFL. Resin tag penetration of the enamel surface for PLP-10 was similar to that previously found for PLP alone, suggesting that the porosity created by phosphoric acid was effectively removed by the acidic PLP adhesive. Significance Unlike some self-etching adhesives reported in the literature, pre-etching enamel did not improve the performance of the Prompt-L-Pop adhesive.

Microleakage of self-etch primer/adhesives in endodontically treated teeth

The authors evaluated the coronal marginal leakage of endodontically treated teeth bonded with four self-etching adhesives and one total-etch adhesive system. The investigators prepared Class II cavities in 60 extracted human premolars. They performed conventional endodontic therapy using a resin-based sealer and gutta-percha points. They randomly assigned each tooth to a group receiving one of the following adhesives: Adper Prompt L-Pop (3M ESPE, Seefeld, Germany), Clearfil SE Bond (Kuraray, Osaka, Japan), FL Bond (Shofu, Kyoto, Japan), Single Bond (3M ESPE) or Xeno III (Dentsply De Trey, Konstanz, Germany). They restored all teeth with resin-based composite material (Z250, 3M ESPE). Specimens underwent thermocycling and dye penetration and were sectioned longitudinally. The authors photographed the sections under a stereomicroscope. They transferred the images to an IBM-compatible personal computer for quantitative assessment of dye penetration using image analysis software. They analyzed data by means of Kruskal-Wallis and Mann-Whitney U tests (P = .05) and evaluated two specimens from each group under scanning electron microscopy. None of the tested self-etch adhesives completely eliminated microleakage. Dye leakage was restricted to the coronal cavity walls; it did not migrate toward the pulp chamber or toward the root canal. Single Bond and Clearfil SE Bond showed significantly lower dye penetration values at occlusal and gingival margins. The coronal sealing performance of the tested self-etch adhesive systems in endodontically treated teeth was material-dependent. The use of Clearfil SE Bond in such teeth can help achieve a marginal seal comparable to that achieved with Single Bond.

The Effect of Modifying the Self-etchant Bonding Protocol on the Shear Bond Strength of Orthodontic Brackets

To compare the shear bond strength (SBS) of orthodontic brackets when the self-etching primer (SEP) and the bracket adhesive are light cured either separately or simultaneously. Seventy-five human molars were randomly divided into five equal groups. Brackets precoated with Transbond XT composite adhesive were used. The five protocols were: Group 1 (control), the SEP Transbond Plus was applied, brackets placed, and adhesive light cured for 20 seconds; Group 2, SEP Adper Prompt L-Pop was applied, light cured, brackets placed, and light cured; Group 3, the same SEP as in Group 2 was used, however, the SEP and bracket adhesive were light cured together; Group 4, SEP Clearfil S3 Bond was applied, light cured, brackets placed, and light cured; and Group 5, the same SEP as in group 4 was used, however, the SEP and the adhesive were light cured together. The teeth were debonded using a universal testing machine, and the enamel was examined for residual adhesive. Analysis of variance was used to compare the SBS. The SBS of Clearfil S3 Bond after one light cure and two light cures were significantly greater than the bonds of brackets using Transbond Plus. Brackets bonded using Adper Prompt L-Pop after one light cure and two light cures were not significantly different from the other groups. The groups did not differ significantly in their bracket failure modes. Only one light curing application is needed to successfully bond brackets when using SEPs and adhesives. This approach can potentially reduce technique sensitivity as well as chair time.

Effect of activation mode of dual-cured resin cements and low-viscosity composite liners on bond strength to dentin

The aim of this study was to investigate the influence of the activation mode of dual-cured resin cements and application of low-viscosity composite liners over self-primed dentin on bond strength (BS) of dentin-bonding agents (DBA). Three DBA (Single Bond; Prompt L-Pop and Clearfil SE Bond), their respective resin cements (RelyX ARC and Panavia F) and two low-viscosity composites (Filtek Flow and Protect Liner F) were tested. After removing the buccal enamel surfaces of 25 bovine incisors, each flat dentin surface was sectioned longitudinally and divided into two similar parts. The dentin surfaces were wet-abraded with 600-grit SiC paper and randomly divided into 10 groups. Experimental groups comprised the use of DBA and their respective dual-cured resin cements, with or without light-activation of resin cements. The low-viscosity resin was used only for the self-etching systems, Prompt L-Pop and Clearfil SE Bond. Three resin cement cylinders (0.5mm high and 0.75mm diameter) were built on each bonded dentin surface, using a tygon tubing mold. After water storage for 24h, specimens were subjected to micro-shear testing. Data were statistically analyzed by two-way ANOVA and Tukey test. Light-activation of resin cements resulted in significantly higher BS for all DBA versus groups in which the resin cements were allowed to self-cure. The low-viscosity composite application increased the BS only for Prompt L-Pop. The bond strength of resin cements to dentin is reduced if light-activation is not employed. The use of a low-viscosity composite liner resulted in improved bond strength only for the single-step self-etching adhesive.

Antibacterial properties of self-etching dental adhesive systems

Dental adhesives with antibacterial properties may reduce recurrent or secondary caries. The authors conducted a study to examine the immediate and long-lasting antibacterial properties of four self-etching adhesive systems. The authors used the agar diffusion test (ADT) and direct contact test (DCT) to measure the antibacterial properties of AdheSe (Ivoclar Vivadent, Schaan, Liechtenstein), Adper Prompt L-Pop (3M ESPE, Seefeld, Germany), Clearfil Protect Bond (Kuraray, Kurashiki, Okayama, Japan) and Xeno III (Dentsply, Konstanz, Germany) on Streptoccocus mutans after aging samples in phosphate-buffered saline for one, two, seven and 14 days. Only Clearfil Protect Bond showed an inhibition halo in the ADT. In the DCT, fresh samples of all of the tested materials exhibited potent antibacterial properties, which were maintained by AdheSe for one day and Clearfil Protect Bond for seven days. None of the adhesive systems exhibited any antibacterial properties after 14 days. All of the tested adhesives had an immediate bactericidal effect on S. mutans. None, however, had long-lasting antibacterial properties. The application of self-etching adhesive materials could contribute to the immediate elimination of residual bacteria. The likelihood of developing secondary caries as a consequence of bacterial microleakage may not be affected by the use of the adhesive systems tested in this study.