Prompt L-Pop Research Articles

Comparative evaluation of shear bond strength of orthodontic brackets bonded with two self-etching adhesive systems: an in vitro study

Abstract Objective To evaluate and compare the shear bond strength (SBS of the new Optibond eXTRa Universal and Adper Prompt L-Pop self-etch adhesive systems using an in vitro experimental design. Patients and methods The sample included 40 freshly extracted human maxillary first premolars collected from orthodontic patients, adhering to ethical guidelines. The teeth were randomly assigned to two groups, one treated with Optibond eXTRa Universal self-etch adhesive and the other with Adper Prompt L-Pop. Stainless-steel brackets were then bonded to the teeth using BracePaste orthodontic adhesive composite resin. After storage and thermocycling, SBS was measured using a universal testing machine, and adhesive remnant index (ARI) scores were assessed under a digital microscope. Statistical analyses were performed, including the Shapiro–Wilk method, Student’s t-test for SBS, and χ 2 test for ARI scores. Results The mean SBS showed no significant difference between both groups (P = 0.076). However, the distribution of ARI scores exhibited a highly significant difference between the two groups (P < 0.001). Conclusion While both adhesives exhibited similar bond strengths, variations in adhesive residue patterns highlight the importance of considering adhesive performance in orthodontic applications such as ease of cleanup and potential impact on enamel health.

Influence of 2% Chlorhexidine on the Bond Strength of Three Adhesive Systems on Primary Molars: An In Vitro Study

The hydrolysis of the collagen matrix by metalloproteinases (MMPs) is one of the paradigms that currently arouses most interest due to its close relationship with a decrease in bond strength (BS) and consequent restoration failure. Chlorhexidine 2% has demonstrated its ability to inhibit MMPs’ activity in the permanent dentition, improving the duration of resin–dentine, but there are few studies on deciduous dentition and its possible repercussions. Aim: To determine the influence of 2% chlorhexidine digluconate (CHX) as a dentine pretreatment on the BS of three adhesive systems on primary molars. Methods: 128 primary extracted molars were assigned to eight groups at random. BS in vitro was recorded by micropush-out test, and analyzed by two-way ANOVA. Results: BS values oscillated from 15.01 MPa to 20.41 MPa. There was no statistically relevant variation between the BS total mean of those adhesive groups that had received CHX pretreatment versus those that did not. Adper Prompt L-Pop was the self-etching adhesive with the best BS. Adper Scotchbond 1XT was the total-etch adhesive with the best BS values. Conclusions: Application of 2% chlorhexidine for 60 s as dentine pretreatment did not affect the immediate BS of several adhesive systems used in primary dentition.

Shear Bond Strength of Repaired Ceramic-Metal Restorations Using Different Bonding Agents with Different Surface Treatments

Background: Fracture of ceramic-metal restorations is a major problem facing the dentists and the patients. There are several bonding systems currently available in the market to repair the fractured ceramic-metal restorations inside or outside the oral cavity. Purpose: The purpose of this study was to test the efficiency of repairing of metal-ceramic restorations using different bonding systems with different surface treatments. This efficiency was tested through the conduction of shear bond strength of the composite bonded to the porcelain and to nickel-chromium alloy using three different bonding agents (Excite, AdheSE, and Prompt L-Pop) with four different surface treatments (sandblasting and enchant, diamond stone roughening, sandblasting and hydrofluoric acid etching, or without surface treatment). Materials and Methods: A total of 120 specimens were prepared, 60 specimens from porcelain and 60 specimens from nickel-chromium alloy. Each group was divided into three equal subgroups, 20 specimens each, corresponding to the 3 bonding agents used. Each subgroup was further subdivided into four subgroups, 5 specimens each, corresponding to the surface treatment procedures. Bonding agents applied over all specimens and cured, followed by application of a micro-hybrid light-cured composite resin (Tetric Ceram). Thermal cycling was done for all specimens between 5°C and 55°C for 1000 cycles with a 10-second dwell time. Shear bond strength test was conducted using a universal testing machine ata cross-head speed of 0.5 mm/min. Results: The highest shear bond strength value recorded for the porcelain specimens bonded with Excite bonding agent with surface treatment sandblasting and hydrofluoric acid etching. In metal groups, the AdheSE bonding agent showed the highest shear bond strength value with the same surface treatment of the porcelain specimens. It was observed that sandblasting followed by hydrofluoric acid etching produced the most effective treatment method for porcelain and metal surfaces. Conclusion: The most effective technique for repairing metal ceramic restoration was sandblasting with hydrofluoric acid etching as surface treatment together with AdheSE or Excite bonding agents.

Knoop Hardness of Self-Etch Adhesives Applied on Superficial and Deep Dentin.

Statement of the Problem: Low pH of self-etch adhesives might cause suboptimal polymerization.Purpose: This study aimed to evaluate the effect of dentin depth (deep and superficial) on polymerization efficacy of two self-etch adhesives, with different pH by means of Knoop hardness test.Materials and Method: In this in vitro study, sixty sound molars were used to prepare 30 superficial dentin and 30 deep dentin specimens. Dentin specimens of each depth were randomly distributed into two equal subgroups (N=15) and bonded by either Adper Prompt L-Pop (strong self-etch adhesive) or Adper Easy Bond (mild self-etch adhesive). Knoop hardness test was employed to evaluate degree of cross-linking of the adhesives. Data were analyzed with SPSS 16, using two-way ANOVA to compare mean hardness values of the study groups (p< 0.05).Results: There was no interaction effect between dentin depth and the type of adhesive (p= 0.36). Regardless of dentin depth, hardness of Adper Easy Bond was significantly higher than that of Adper Prompt L-pop (p< 0.001). Moreover, both the adhesives showed higher hardness when bonded to superficial dentin compared to deep dentin (p< 0.001).Conclusion: Degree of cross-linking of the self-etch adhesive with mild acidity was more than that of the strong self-etch adhesive after light-curing. Surface hardness of both adhesives was higher on superficial dentin compared to deep dentin.

Effect of Simulated Pulpal Pressure on Knoop Hardness of Two Self-etch Adhesives with Different Aggressiveness

Simulated pulpal pressure (PP) has been shown to affect the bond strength and nanoleakage of different adhesives at dentin interfaces but the effect of simulated PP on polymerization of adhesives has not been studied yet. Furthermore, it has been proposed that strong and mild self-etch adhesives have different polymerization behaviors. This study aimed to evaluate the effect of simulated PP on polymerization of two self-etch adhesives, Adper Prompt L-Pop (APLP) and Adper Easy Bond (AEB), by means of the Knoop hardness test. Sixty caries-free human molars were used to prepare deep dentin specimens with a mean remaining dentin thickness of 0.9 mm. The specimens were bonded in the absence or presence of PP. The specimens were assigned to four equal groups (n = 15) as follows: AEB/-PP, APLP/-PP, AEB/+PP, and APLP/+PP. Bonding procedures were completed; then the specimens' hardness was measured with the Knoop test. Data were analyzed with two-way ANOVA and the t test. In the absence of PP, the hardness of AEB was significantly higher than that of APLP (p < 0.001). In contrast, when PP was simulated, the hardness of APLP was higher than that of AEB (p = 0.002). The hardness of AEB was not influenced by the presence of PP (p = 0.153). Simulation of PP resulted in a significant improvement in the hardness of APLP (p < 0.001). The polymerization degree of strong self-etch adhesive was lower compared to mild self-etch adhesive. In the presence of hydrostatic PP, the polymerization degree of strong self-etch adhesive was higher than mild self-etch adhesive. Dentin moisture caused by positive PP might improve polymerization of strong self-etch adhesives.

Comparative evaluation of shear bond strength of sixth- and seventh-generation bonding agents with varying pH - An in vitro study.

Introduction:To compare and evaluate the shear bond strength of sixth- and seventh-generation bonding agents with varying pH – an in vitro study.Materials and Methods:Eighty extracted human premolar teeth were collected and cleaned and polished with pumice and water. The root portion of teeth was resected, and only the coronal portion was embedded in the cold-cure acrylic resin. The labial surface of mounted teeth was prepared with a high-speed handpiece using #245 carbide bur. The samples prepared were divided into four groups, with 20 specimens in each group: Group A: Sixth-generation bonding agent, Adper Prompt L-Pop (APLP) (3M ESPE)Group B: Sixth-generation bonding agent, Xeno III (X III) (Dentsply)Group C: Seventh-generation bonding agent, Adper Easy One (AEO) (3M ESPE)Group D: Seventh-generation bonding agent, Xeno IV (X IV) (Dentsply). Tooth surface were rinsed and dried, and bonding agents were applied on tooth surface. Composite resin (Z-350 XT, 3M ESPE) was placed in a two-layer increment on tooth and was light cured. Specimens were subjected to the universal testing machine in a compression mode force at a crosshead speed of 1 mm/min keeping blade parallel to the adhesive–dentin interface. Shear force required to debond the specimen was recorded in megapascal. The data obtained were analyzed statistically using ANOVA and post hoc test.Results:AEO (pH = 2.3, Group C seventh generation) showed higher bond strength, and pH values did not influence the shear bond strength significantly in the tested adhesive systems.Conclusion:The pH values did not influence the shear bond strength significantly in the tested adhesive systems. ADPER EASY ONE (pH= 2.3, GROUP C Seventh Generation) showed higher bond strength followed by XENO IV(pH = 2.1, GROUP D), XENO III (pH = 1.5, GROUP B) on dentinal surface ,where as ADPER PROMPT L POP (pH =0.7 to 1 Sixth Generation, GROUP A) showed lower bond strength.

Comparison of shear bond strength of traditional 3-step composite with self etch primer and composite.

The revolution in orthodontics has been due to replacement of cemented bands by orthodontic brackets. Acid etching is required to bond a bracket on tooth’s surface. Traditional three step acid etch procedure consisted of etching, sealing/priming and bonding. The self etch system (etchant and primer together) can be used without the need for surface preparation, saving chair side time and minimizing contamination. Objectives: To compare the shear bond strength (SBS) of orthodontic bracket bonded with Conventional etching primer (Transbond XT, 3M Unitek) with self etch primer (Adper Prompt L-Pop, 3M ESPE). Study Design: Prospective study Setting: Orthodontic Clinic of Ihsan Mumtaz Hospital, Lahore and PCSIR (Lahore). Period: 6 months from June 2018 to December 2018. Material and Methods: 60 human maxillary premolars were randomly divided into 2 groups of 30 each. Group-I was bonded with conventional etching primer + composite and Group-II was bonded with self etch primer + composite. Shear bond strength was measured through Ionstron force testing machine. Statistical Analysis: For each variable, shear bond strength, arithmetic mean, standard deviation, minimum and maximum values were calculated. t-test was used to compare the shear bond strength (SBS) of the two groups and P value less than and equal to 0.05 was considered significant. Results: The mean shear bond strength in group 1 and group II was10.5MPa and 7.36MPa respectively. Conclusion: The shear bond strength of Conventional etching primer + adhesive was significantly higher than the shear bond strength of self etch primer +adhesive group.

Longevity of posterior composite and compomer restorations in children placed under different types of anesthesia: a retrospective 5-year study

The aims of this study were (i) to assess cumulative survival rates of class II resin-based composite and compomer restorations in primary molars with a 5-year observation period and (ii) to analyze the influence of different types of anesthesia and different localizations of the restorations in the teeth. Patient charts of a private practice for pediatric dentistry were screened for class II resin-based composite (Spectrum TPH3) and compomer (Dyract Posterior; both Dentsply DeTrey) restorations in primary molars with a 5-year observation period used with Adper Prompt L-Pop (3M-ESPE). One restoration per patient (age ≤ 6years at placement) was randomly selected. Two hundred sixty restorations were included (43% resin-based composites, 57% compomers). After 5years, cumulative survival rates were 43% for resin-based composite and 49% for compomer restorations with no statistically significant differences. There was a tendency for higher survival rates for restorations placed under N2O inhalation sedation or general anesthesia. Distal-occlusal compomer restorations showed significantly lower survival rates (p = 0.003) as compared to mesial-occlusal compomer restorations. Within the limitations of the study, we conclude that type of restorative material as well as the type of anesthesia do not influence restoration survival rates, although restorations placed in patients receiving N2O inhalation sedation or general anesthesia tend to perform better as compared with patients receiving no anesthesia or only local infiltration. Resin-based composite and compomer restorations show similar survival rates of more than 43% (annual failure rates less than 11.5%) after 5years for restoration of primary molars.

Avaliação da resistência da união imediata à dentina de sistemas adesivos simplificados

Objetivo: Avaliar quatro sistemas adesivos comerciais de diferentes composições quanto ao desempenho da resistência da união à dentina.&#x0D; Métodos: Vinte incisivos bovinos tiveram a dentina vestibular exposta e receberam restaurações de resina confeccionadas com quatro (n=5) diferentes sistemas adesivos simplificados: Magic Bond DE e OptiBond Solo (convencionais), One-Up Bond F e Adper Prompt L-Pop (auto-condicionantes). Os dentes foram seccionados perpendicularmente a interface adesiva utilizando-se um disco de diamante, de modo a se obter palitos de 1mm² de área de secção. Os palitos foram submetidos ao ensaio de micro-tração em uma máquina de ensaios universal. Os valores médios de resistência de união dos diferentes sistemas adesivos foram comparados utilizando-se ANOVA de uma via e teste Tukey, em um nível de significância de 5%.&#x0D; Resultados: Os valores médios de resistência da união foram 48,81±0,56 para o Magic Bond DE, 47,52±13,03 para o OptiBond Solo, 44,68±13,32 para o One-Up Bond F e 31,59±11,81 para o Adper Prompt L-Pop. O adesivo Adper Prompt L-Pop apresentou resistência de união inferior a dos adesivos convencionais (p

Bonding effectiveness of self-etch adhesives to dentin after 24 h water storage.

Purpose:This study evaluated the immediate bonding effectiveness of five self-etch adhesive systems bonded to dentin.Materials and Methods:The microtensile bond strength of five self-etch adhesives systems, including one two-step and four one-step self-etch adhesives to dentin, was measured. Human third molars had their superficial dentin surface exposed, after which a standardized smear layer was produced using a medium-grit diamond bur. The selected adhesives were applied according to their respective manufacturer's instructions for μTBS measurement after storage in water at 37°C for 24 h.Results:The μTBS varied from 11.1 to 44.3 MPa; the highest bond strength was obtained with the two-step self-etch adhesive Clearfil SE Bond and the lowest with the one-step self-etch adhesive Adper Prompt L-Pop. Pretesting failures mainly occurring during sectioning with the slow-speed diamond saw were observed only with the one-step self-etch adhesive Adper Prompt L-Pop (4 out of 18).Conclusions:When bonded to dentin, the self-etch adhesives with simplified application procedures (one-step self-etch adhesives) still underperform as compared to the two-step self-etch adhesive Clearfil SE Bond.

Effects of Additional Acid Etching on the Dentin Bond Strengths of One-Step Self-Etch Adhesives Applied to Primary Teeth.

The aim of this study was to evaluate the bond strengths of one-step self-etch adhesives applied to primary tooth dentin with and without additional acid etching. In total, 154 specimens were prepared using 50 naturally exfoliated primary molars. Four commercial one-step self-etch adhesives were used in this study: Scotchbond™ Universal, All-Bond Universal™, Adper™ Prompt™ L-Pop™, and Clearfil S3 Bond™. Two etch-and-rinse adhesives, Prime & Bond® NT™ and Scotchbond™ Multi-Purpose, served as controls. Microtensile bond strength tests were performed for specimens treated with the one-step self-etch adhesives with and without additional acid etching and those treated with the two etch-and-rinse adhesives. All one-step self-etch adhesives except Adper Prompt L-Pop exhibited increased microtensile bond strength values (p < 0.05) with additional acid etching. A nonsignificant interaction was observed between the type of self-etch adhesive and additional acid etching (p = 0.056). Bond strength comparisons between the self-etch adhesives used without additional acid etching and the etch-and-rinse adhesives revealed significantly higher values for Prime & Bond NT than for All-Bond Universal® (p < 0.05). However, there were no significant differences between any etch-and-rinse adhesive and self-etch adhesive used with additional acid etching, although Clearfil S3 Bond showed greater strength than Adper Prompt L-Pop. Our results suggest that additional acid etching increases the bond strength of most one-step self-etch adhesives applied to primary tooth dentin. Additional acid etching of enamel and dentin can be recommended to increase the bond strength of one-step self-etch adhesives applied to primary teeth. (J Esthet Restor Dent 29:110-117, 2017).

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

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

Assessment of the initial and aged dentin bond strength of universal adhesives

This study evaluated the effect of mechanical loading on microtensile bond strengths (μTBS) of universal adhesives to dentin and quantified adhesive dentin penetration using micro-Raman spectroscopy. Human molars had occlusal dentin exposed and were allocated into eight groups: All-Bond Universal and Scotchbond Universal using etch-and-rinse and self-etch approaches, Adper Prompt L-Pop, Adper Single Bond Plus, Clearfil SE Bond, and Optibond FL. Following bonding procedures and build-ups, specimens were either stored in water at 37°C for 24h or mechanically loaded (50,000 cycles, 50N) prior to μTBS test. Additional teeth were prepared for micro-Raman analysis of adhesive penetration and FE-SEM. Data were analyzed by two-way ANOVA and Tukey׳s post hoc test (P<0.05). Mechanical loading had no deleterious effect on μTBS with the exception of Adper Prompt L-Pop. Incomplete infiltration of the demineralized dentin was noticed for adhesives using the etch-and-rinse approach and for Scotchbond Universal in the self-etch approach.

Clinical Effect of Dental Adhesive on Marginal Integrity in Class I And Class II Resin-Composite Restorations.

Dental adhesives are believed to influence marginal adaptation and marginal discoloration when used under posterior resin-based composite restorations. Studies on the latest adhesive systems reveal that the group of the three-step etch-and-rinse adhesive (3-E&RA) and the one-step self-etch adhesive (1-SEA) have entirely different bonding mechanisms, as well as different bond strength and resistance to chemical, thermal and mechanical factors. A hypothesis that a 1-SEA would result in greater enamel marginal discoloration and poorer marginal adaptation than a 3-E&RA was tested. One hundred restorations were placed with a 1-SEA and 100 restorations with a 3-E&RA. Teeth were restored with Filtek Supreme nanofilled resin-composite and were evaluated for marginal adaptation and marginal discoloration at baseline, and 6 months, 12 months, and 36 months postoperatively. The statistical analysis revealed significant differences in marginal integrity between test groups. The 1-SEA resulted in greater enamel marginal discoloration and poorer marginal adaptation than the 3-E&RA at any recall time. Marginal adaptation and marginal discoloration depend on the type of dentin adhesive used. The restorations with Filtek Supreme and Scotchbond MP are better than the restorations with Adper Prompt L-Pop with regard to the marginal adaptation and marginal discoloration at 6-, 12- and 36-month evaluations.

The effect of different adhesives and setting times on bond strength between Biodentine and composite.

The aim of this study was to evaluate the effects of 3 different adhesives with different functional monomers, on the shear bond strength (SBS) of Biodentine®. Acrylic blocks (n = 90) were prepared and a 2-mm height x 4-mm diameter hole was opened in each block. Every hole was completely restored with Biodentine®. Before preparation of composite restorations over the Biodentine® (2-mm height x 2-mm diameter), 3 different adhesives (Etch-37 (37%) w/BAC by Bisco &amp; Prime Bond N&amp;T, Clearfil S3 Bond and Adper Prompt L-Pop) were applied. SBS was evaluated using a universal testing machine, and failure mode for each sample was recorded. The results were statistically analyzed using 2-way ANOVA and post hoc Tukey test. When the megapascal values of all groups were compared, although there was no statistically significant difference in the different setting times (p&gt;0.05), statistically significant differences were observed among all adhesive groups (p&lt;0.05). Moreover, the highest SBS values were observed in the Clearfil S3 Bond group. Clinical performance of Biodentine® may be affected by adhesive procedures and its setting time.

Effect of dentin dehydration and composite resin polymerization mode on bond strength of two self-etch adhesives

Background:Dual-cured composite resins are similar to self-cured composite resins in some of their clinical applications due to inadequate irradiation, lack of irradiation, or delayed irradiation. Therefore, incompatibility with self-etch adhesives (SEAs) should be taken into account with their use. On the other, the extent of dentin dehydration has a great role in the quality of adhesion of these resin materials to dentin. The aim of this study was to investigate the effect of dentin dehydration and composite resin polymerization mode on bond strength of two SEAs.Materials and Methods:A total of 120 dentinal specimens were prepared from extracted intact third molars. Half of the samples were dehydrated in ethanol with increasing concentrations. Then Clearfil SE Bond (CSEB) and Prompt L-Pop (PLP) adhesives were applied in the two groups. Cylindrical composite resin specimens were cured using three polymerization modes: (1) Immediate light-curing, (2) delayed light-curing after 20 min, and (3) self-curing. Bond strength was measured using universal testing machine at a crosshead speed of 1 mm/min. Data were analyzed with two-way ANOVA and Duncan post hoc tests. Statistical significance was defined at P < 0.05.Results:There were no significant differences for CSEB subgroups with hydrated and dehydrated dentin samples between the three different curing modes (P > 0.05). PLP showed significant differences between subgroups with the lowest bond strength in hydrated dentin with delayed light-curing and self-cured mode of polymerization.Conclusion:Within the limitations of this study, a delay in composite resin light-curing or using chemically cured composite resin had a deleterious effect on dentin bond strength of single-step SEAs used in the study.

Shear bond strength and microleakage of a self-etching adhesive for fissure sealing after different types of aging.

The aim of this study was to evaluate shear bond strength (SBS) and microleakage of a self-etching adhesive (Adper Prompt L-Pop) in comparison to acid etching prior fissure sealing. Each procedure was tested with 3 aging procedures (1-day water storage, 3-month water storage and 1-day water storage/5,000× thermocycling). SBS was determined according to ISO standard 29022. Additional 30 third molars were utilized for the microleakage analyses. Data were analyzed using Mann-Whitney-U-Test and multiple linear regression models. The SBS of the self-etching adhesive were significantly lower (14.9, 11.9, and 13.0 MPa) than those of conventional fissure sealing (19.1, 18.2, and 15.6 MPa). Multiple linear regression models predicted that material and alteration significantly influenced SBS. The microleakage revealed no difference between both groups (1.3% vs. 1.2%). It can be concluded that the selfetching adhesive might be a pre-treatment alternative for fissure sealing in terms of the easier and shorter clinical workflow.

Bond durability of contemporary adhesive systems to pulp chamber dentin

Objective: The purpose of this study was to evaluate long-term bond strengths of dentin adhesive systems, which include one-step self-etch adhesive systems (Optibond All-in-one, Kerr; Adper Prompt L-POP, 3 M ESPE), a three-step etch-and-rinse adhesive (Optibond FL, Kerr) and two-step self-etch adhesive (AdheSE Bond, Ivoclar), applied to pulp chamber dentin surfaces after 12-month water storage by using microtensile bond strength (µTBS) test.Materials and methods: Dentin adhesive systems were applied to unprepared pulp chamber dentin surfaces according to manufacturer’s directions, respectively (n = 5). After applying adhesive systems, composite buildups were done incrementally. Bond strengths to pulp chamber dentin surfaces were determined using µTBS test after water storage for 24 h and 12 month. Kruskal–Wallis analysis and Mann–Whitney U-test for pairwise comparisons were used to determine statistical differences in µTBS between the groups at a significance level of 5%.Results: There were no significant differences in µTBS between storage periods for tested adhesives regardless adhesive class.Conclusion: Bond durability of tested adhesive systems, including one-bottle self-etch adhesives with pulp chamber dentin surfaces, may be considered stable after 12-month water storage. Therefore, one-step self-etch, also called “user-friendly” adhesives may perform and traditional three-step etch-and-rinse adhesives in the long-term when used for bonding to pulp chamber dentin surfaces.

Effects of thermomechanical and thermocycling on the shear bond strength of brackets to bovine enamel bonded with conventional and self-etching adhesive systems

Several adhesive systems have been developed in the last decade. The aim of the current study was to evaluate the shear bond strength of orthodontic brackets bonded with conventional primers or self-etching primers, artificially aged by means of thermocycling and thermomechanical procedures.90 bovine incisors were used in the investigation. The roots were sectioned in the amelo-cementary junction. All samples were randomly divided in 2 groups ( n= 45), according to the primer used for bracket bonding. XT Group–hydrophobic conventional primer (Transbond XT, 3M unitek, Monrovia, Calif); SEP Group –self-etching primer (Transbond Plus SEP, 3 M Unitek, Monrovia, Calif). All specimens were bonded with XT Transbond resin adhesive (3 M Unitek, Monrovia, Calif). A Universal Testing Machine EMIC DL2000 (EMIC Equip. Sist. Ensaio Ltda., São José dos Pinhais, PR, Brazil) was used for the collection of the values of SBS resistance. The results of the current study were: (Prompt L-Pop 1.72±0.13 MPa; Clearfil SE Bond 1.75±0.19 MPa; FL Bond 1.71±0.22 MPa; One-Up Bond 1.77±0.14 MPa; XT Control 10.5±0.86 MPa). In conclusion: the number of cycles in thermal and thermo mechanical cycling did not influence shear bond strength values for any of the primers tested;SEP Transbond Plus showed the greatest values for bond strength of orthodontic brackets.

Evaluation of bond strength of self-etching adhesives having different pH on primary and permanent teeth dentin.

The purpose of this in vitro study was to evaluate the dentin shear bond strength of 4 self-etching adhesives having a different pH on primary and permanent teeth dentin. The occlusal enamel was removed from 60 freshly extracted third molar and 60 primary second molar human teeth, which were randomly separated into 4 groups (n = 15). Four adhesive systems were applied: G-Bond (GC Corporation, Tokyo, Japan, pH: 1.5), Futura Bond M (Voco, Cuxhaver, Germany, pH: 1.4), Adper Prompt L-Pop (3M/ESPE, St Paul, MN, USA, pH: 0.8), and Clearfil S(3) Bond (Kuraray Medical, Tokyo, Japan, pH: 2.7) according to the manufacturer's instructions. After the application of dentin bonding agents, a composite resin material (Z250 Restorative A2, 3M ESPE, St. Paul, MN, USA) for permanent teeth and a compomer resin material (Dyract Extra A2, Dentsply, Konstanz, Germany) for primary teeth was applied onto the prepared dentin surfaces. The data were obtained by using a universal test machine at a crosshead speed of 1 mm/min. The mean values were compared using Tukey's multiple comparison test. Although there was no difference between adhesives on the permanent teeth, Clearfil S3 adhesive showed higher bond (18.07 ± 0.58 MPa) (P>0.05). Lower bond strength values were obtained from primary teeth and especially G-Bond adhesive (9.36 ± 0.48 MPa) (P<0.05). Self-etching adhesives with different pH and solvent types can be used successfully for permanent teeth dentin but adhesives with low pH did not provide greater shear bond strength values.