Self-etch Adhesive Systems Research Articles

Selection of adhesive systems in treatment of tooth root caries (literature review)

Adhesive dentistry is the foundation on the basis of which there have been global changes in the concept of adhesion of composite materials in therapeutic dentistry, protocols for fixing ceramic restorations in orthopedic dentistry. But a number of unsolved problems remained – the adhesion of composite materials to sclerosed dentin and tooth root cement, the sensitivity of the components of the adhesive systems to the wet environment of the oral cavity and spatial stability in the presence of dentinal fluid moving centrifugally in the dentinal tubules, the lack of restoration of periodontal attachment to the defect that occurs during tooth root caries. The review analyzes the results of studies on the use of self-etching adhesive systems in the treatment of root caries. The physician's ability to choose an adhesive system in a particular clinical case demonstrates his fundamental knowledge and minimizes the percentage of errors that he can make during the treatment phase.

Clinical effectiveness of direct resin composite restorations bonded using one-step or two-step self-etch adhesive systems: A three-year multicenter study

The purpose of this multicenter clinical study was to compare the mid-term clinical effectiveness of direct resin composite restorations using one-step or two-step self-etch adhesives (1-SEAs or 2-SEAs). In total, 352 restorations of class I-V cavities and non-carious cervical lesions in vital teeth (1-SEAs; 52 cases, 2-SEAs; 300 cases) were placed at nine university hospitals and evaluated according to the modified USPHS criteria at baseline, and after 1, 2, and 3 years. The recall rates were 86.6% (1 year), 80.1% (2 years), and 62.2% (3 years). Two restorations failed due to fracture during the follow-up, and there was no significant difference in survival rates between 1-SEAs (97.6%) and 2-SEAs (99.4%). However, 2-SEAs exhibited significantly lower occurrences of discoloration, marginal discoloration, fracture, and plaque retention. Moreover, the subjects reported a significantly lower postoperative hypersensitivity and higher overall satisfaction at all evaluation periods if 2-SEAs were used.

INFLUÊNCIA DO USO DA PROANTOCIANIDINA EM UM ADESIVO AUTOCONDICIONANTE: AVALIAÇÃO DA RESISTÊNCIA DE UNIÃO

Introdução: Os sistemas adesivos possibilitam a execução de restaurações estéticas e minimamente invasivas, sendo, portanto, objeto de pesquisas para contornar os problemas que se apresentam no procedimento restaurador. Objetivo: Avaliar in vitro a resistência de união de um sistema adesivo autocondicionante, e deste modificado com soluções extrativas de semente de uva. Metodologia: Duas soluções extrativas foram preparadas com extrato de semente de uva em pó dissolvido em acetona e etanol. A partir delas e de um adesivo, seis sistemas adesivos autocondicionantes experimentais foram preparados, diferindo quanto ao solvente utilizado e às proporções entre adesivo puro e solução extrativa, esta, variando em 7,5%, 15% e 30%. Setenta incisivos bovinos hígidos tiveram as raízes removidas com disco de carborundum e as faces vestibulares desgastadas com lixas d’água de granulação 120, 240, 600 e 1200 sob refrigeração até expor a dentina superficial. Os dentes foram distribuídos aleatoriamente em sete grupos distintos: Controle; A7,5; A15; A30; E7,5; E15; e E30, contendo 10 elementos cada. A aplicação dos adesivos foi executada de acordo com as recomendações do fabricante do adesivo controle. A restauração foi realizada com uma matriz de silicone com dimensões 2 mm de altura e 4 mm de diâmetro e inserido o material restaurador em incremento único e fotopolimerizado por 40s. Após três meses armazenados em água destilada, os espécimes foram submetidos ao teste de resistência de união. Foi empregado o método estatístico Teste Paramétrico Anova 1 Fator e pós- teste de Tamhane (p<0,05). Resultados: Os grupos A7,5, E7,5 e E30 não apresentaram diferença em relação ao grupo Controle; A15 e A30 mostraram desempenho estatisticamente semelhante entre si; e E15 não apresentou diferença estatística em relação aos outros adesivos. Conclusões: A adição de proantocianidina teve efeitos diferentes, dependendo dos solventes e das concentrações utilizadas, mas sem alterar significativamente o desempenho do adesivo.

Microtensile Bond Strength of Fiber-Reinforced and Particulate Filler Composite to Coronal and Pulp Chamber Floor Dentin

This ex vivo study aimed to compare the microtensile bond strength of fiber-reinforced and particulate filler composite to coronal and pulp chamber floor dentin using a self-etching adhesive system. Coronal dentin of 40 human molar teeth was exposed by cutting occlusal enamel with a low-speed saw. Teeth were then randomly divided into two groups (n = 20). The first group was left as is, while in the second group, pulp chamber floor dentin was exposed by trepanation. After placement of a self-etching adhesive system (G-aenial Bond, GC, Tokyo, Japan), groups were further divided into two sub-groups (n = 10) according to the type of composite: fiber-reinforced composite (EP, everX Posterior, GC, Tokyo, Japan) and particulate filler composite (GP, G-aenial Posterior, GC, Tokyo, Japan). Then, composite blocks were built up. Sticks (1.0 × 1.0 mm2) were obtained from each specimen by sectioning, then microtensile bond strength (μTBS) test was performed. Statistical analysis included one-way ANOVA test and Student’s t-test (p < 0.05). μTBS values were 22.91 ± 14.66 and 24.44 ± 13.72 MPa on coronal dentin, 14.00 ± 5.83 and 12.10 ± 8.89 MPa on pulp chamber floor dentin for EP and GP, respectively. Coronal dentin yielded significantly higher μTBS than pulp chamber floor dentin (p < 0.05), independently from the tested composites.

Evaluation of internal adaptation of flowable and bulk-fill resin-based composites

This study aimed to evaluate and compare the internal adaptation of bulk-fill resin-based composite restorative materials with flowable composites as lining materials using self-etch adhesive system. Class I cavities (2mmx4mm) were prepared on flattened occlusal surfaces of fifty extracted human premolars and randomly assigned into five groups (n=10) according to the materials used: Beautifil Bulk-fill Restorative (BR); Beautifil Bulk-fill Flowable (BF); Beautifil Flow Flowable F10 (BF10); and Self-etch adhesive (SEA). Group A: SEA+BR; Group B: SEA+BF10+BR; Group C: SEA+BF+BR; Group D: SEA+BF10+SEA+BR and Group E: SEA+BF+SEA+BR. The samples were thermocycled for 500 cycles, then sectioned mesiodistally, polished and pre-treated prior to scanning electron microscopy (SEM) evaluation. From SEM images, measurement of adhesive and cohesive adaptation failures was recorded at multiple sites of the pulpal floor and in between materials. Data were analysed using one-way ANOVA and post-hoc Tukey tests (p&lt;0.05). Cohesive failure in SEA was observed at the pulpal floor with the lowest percentage in Group A (5.14%), and highest in Group C and E (&gt;16%). However, there were no significant difference among all groups. Adhesive failure was seen at the pulpal floor between SEA+BF/BF10/BR and between SEA+dentine with the highest percentage of gaps formed in Group A between SEA+dentine (6.62%) and SEA+BR (5.30%). Nonetheless, no significant differences were observed among all groups with p=0.89 and p=0.70, respectively. With the use of BF/BF10 at the pulpal floor, adhesive failure was reduced but resulted in increased of cohesive failure. However, both adaptation failures were absent between materials (BF/BF10 and BR) regardless with or without application of SEA.

Development and characterization of self-etching adhesives doped with 45S5 and niobophosphate bioactive glasses: Physicochemical, mechanical, bioactivity and interface properties

ObjectiveThe aim of study was to develop and characterize experimental bioactive glasses (45S5 and niobophosphate bioactive glass (NbG)) and evaluate the effects of their addition in self-etching adhesive systems on physicochemical, mechanical, and bioactive properties, microtensile bond strength (μTBS), and nanoleakage (NL). MethodsTwo-step self-etching adhesive systems containing 5, 10, and 20 wt.% of 45S5 and NbG bioactive glasses were developed. An experimental adhesive without microparticles and a commercial adhesive (Clearfil SE Bond) were used as control groups. The materials were evaluated for their degree of conversion (DC%), ultimate tensile strength (UTS), softening in solvent, radiopacity, sorption and solubility, alkalizing activity (pH), ionic release, and bioactivity. μTBS and NL were evaluated after 24 h and 1 year of storage. The data were subjected to analysis of variance and post-Holm-Sidak tests (α = 0.05). ResultsThe addition of the two bioactive glasses did not change the values of the degree of conversion, ultimate tensile strength, and softening in solvent. The adhesive system containing 20% NbG showed the highest radiopacity. The incorporation of 45S5 increased water sorption and solubility, raised the pH, and allowed the release of large amounts of calcium. After 28 days of immersion in simulated body fluid, the 45S5 adhesive precipitated hydroxyapatite and calcium carbonate (SEM/EDX, ATR/FTIR, and XDR). The addition of 45S5 and NbG to the adhesives improved the stability of the resin-dentin interface after 1 year. SignificanceThe incorporation of microparticles from 45S5 bioactive glass in self-etching adhesive systems is considered an excellent alternative for the development of a bioactive adhesive that improves the integrity of the hybrid layer on sound dentin.

Assessment of permeability of eroded dentin after the use of universal, self-etch, and conventional systems.

Dentin hypersensitivity is caused by increased dentinal permeability due to total or partial exposure of dentinal tubules, which in turn can be produced by alterations of dental structures or failure of restorative procedures. The purpose of this in vitro study was to evaluate the efficacy of the application of different kinds of adhesive systems to prevent dentin permeability before and after an erosive challenge. Fifty bovine dentin discs (6x1 mm) were prepared and the specimens were divided into 5 groups (n=10): (SB2) Single Bond 2, (SBU) Universal Single Bond, (CSB) Clearfil SE Bond, (SM) Scotchbond Multipurpose and (C) Control. Hydraulic conductance of dentin was recorded after adhesive application (HC-1) and after erosive challenge (HC-2). Dentin surface images of post-treatment and post-erosive challenge were obtained by scanning electron microscopy (SEM). Data were analyzed using Kruskal Wallis, Mann-Whitney with Bonferroni correction and Wilcoxon tests (p<0.05). Reduction in dentin permeability was observed with the application of adhesive systems (p<0.05). After the erosive challenge, dentin permeability increased for SBU and CSB (p<0.05), while SB2 and SM did not differ in HC-1 or HC-2 (p>0.05). The conventional, self-etching and universal adhesive systems reduce dentinal permeability by more than 80%, and dentin demineralization may contribute to the increased permeability of universal and self-etching systems.

Effect of captopril pretreatment on the dentin bonding durability of self-etch adhesive.

To investigate the effect of captopril on the dentin bonding durability of self-etch adhesive. Different concentrations of captopril ethanol solutions or captopril ethanol/water solutions were prepared to pretreat dentin as primer for the self-etch adhesives. The surface morphology of the dentin was observed with scanning electron microscopy (SEM). Based on the morphology analysis, the pretreatment condition was selected and two self-etch adhesives were employed to evaluate the improvement effect of the captopril pretreatment on the dentin bonding durability. : SEM showed that the pretreatment of captopril ethanol solutions and captopril ethanol/water solutions were able to remove the smear lay and partially expose collagen matrix. According to the SEM results, the pretreating condition of captopril ethanol/water solution with the pretreating time of was selected for further dentin bonding study. For Clearfil SEBOND system, the immediate bonding strength increased from to (<0.05). After one-year aging, the bonding strength of the control group decreased markedly [(22.90±6.82) MPa, <0.05]; while the bonding strength of the captopril pretreated group kept steadily >0.05]. For Clearfil S BOND system, there was no significant difference in the immediate bonding strength between the experimental group [(4.07) MPa] and the control group[(4.11) MPa]. But after one-year aging, the bonding strength of the experimental group was higher than that of the control group <0.05]. : The pretreatment with captopril ethanol/water solution increases the dentin bonding strength of the self-etch adhesive systems and also improves the bonding durability.

Effect Of Chitosan Treatment On Shear Bond Strength Of Composite To Deep Dentin Using Self-Etch And Total-Etch Adhesive Systems

Objective: To assess the shear bond strength (SBS) of resin composite to deep dentin, using 1 and 2.5% chitosan pretreatment as well as different adhesive systems. Material and Methods: 80 human maxillary molars were randomly divided to eight groups according to the type of adhesive system and dentin pretreatment (n = 10): I) two-step self-etch system (Clearfil SE bond); II) two-step etch-andrinse system (Adper single bond 2); III) 2.5% chitosan + Clearfil SE bond; IV) 2.5% chitosan +etch + Adper single bond 2; V) etch + 2.5% chitosan + Adper single bond 2; VI) 1% chitosan + Clearfil SE bond; VII) 1% chitosan + etch + Adper single bond 2; VIII) etch + 1% chitosan + Adper single bond 2 (chitosan solution (w/v): 2.5 g and 1 g of chitosan (Sigma Aldrich, USA) was dissolved in 100 ml of 1% acetic acid). Plastic molds were positioned on dentin and filled with composite (Z350, 3M ESPE, USA). SBS (MPa) was tested using a universal testing machine. ANOVA tests, Tukey’s test, and independent t test were used to analyze data (p &lt; 0.05). Results: The highest SBS value among self-etch groups was observed with 1% chitosan (p = 0.001). In the etch-and-rinse group, the SBS of 1% chitosan was significantly lower than the other groups. Chitosan treatment following acid etching led to higher SBS in comparison to when chitosan was applied before etching, with the significant difference in 1% concentration (p = 0.030). A predominance of mix fractures was observed in dentin. Conclusion: Improved dentin bond strength can be achieved through immediate dentin pretreatment with 1% chitosan in self-etch adhesive systems. Chitosan Pretreatment may not be advantageous for etch-and-rinse adhesive systems. Keywords Adhesive system; Chitosan; Deep dentin; Shear strength.

Effect of repair systems on dentin bonding performance.

The purpose of this study was to investigate the influence of phosphoric acid etching, metal primer or silane coupling agent application on dentin bonding performance of a 2-step self-etch adhesive system. Human dentin surfaces were prepared and divided into four groups depending on the pre-treatment method: no pretreatment (Clearfil SE Bond 2, CONTROL); 40% phosphoric acid (K-Etchant GEL, K); metal primer (Alloy Primer, AP); or silane coupling agent (Porcelain Bond Activator, PB). The specimens were sectioned into beams, separated into 2 subgroups (n=20): no thermocyling or thermocycled (TC), and subjected to a µTBS test and an acid-base challenge for SEM observation. Statistically lower results were observed between K and AP groups, PB and CONTROL, and PB with/without TC (p<0.05). SEM images at the dentin-adhesive interface revealed that all groups produced an acid-base resistant zone (ABRZ), with a funnel-shaped erosion under the ABRZ for the K group.

Evaluation of the Bond Strength of Different Pulp Capping Materials to Dental Adhesive Systems: An In Vitro Study

Aim: To evaluate the bond strengths of pulp capping materials (Dycal, ProRoot MTA, Biodentine, TheraCal LC, Calcimol LC, and ApaCal ART) and different adhesive systems (Gluma 2 Bond, Clearfil SE Protect, Gluma Self Etch, Clearfil S 3 Bond Plus, Gluma Bond Universal, Clearfil S 3 Bond Universal). Materials and Methods: Two hundred fifty-two acrylic blocks were prepared in which cylindrical cavities of 4 × 2 mm 3 were formed. Pulp capping materials were placed in the cavities. Different adhesive systems were applied to each pulp capping material group. After applying the composite resin, the shear bond strength (SBS) values of the specimens were determined in the Instron test device. Fracture types were evaluated using a stereomicroscope and a scanning electron microscope. Data were analyzed by Shapiro–Wilk’s and Kruskal–Wallis H test. Results: There is a statistically significant difference between pulp capping materials in terms of SBS values ( P &lt; .05). Dycal’s SBS was found significantly lower than other materials, and the highest bond strength was observed in Calcimol LC material. Although there is no statistically significant difference ( P &gt; .05) between the adhesive agent groups in terms of SBS, Gluma 2 Bond showed the highest bond strength value. Conclusion: In traditional pulp capping materials such as Dycal, MTA, and Biodentine, using a two-step self-etch adhesive system can result in higher bond strength values. In resin-based TheraCal LC,, ApaCal ART, and Calcimol LC materials, it may be recommended to use a two-step etch and rinse adhesive system.

Evaluation of human pulp tissue response following direct pulp capping with a self-etching adhesive system containing MDPB.

This study evaluated the human pulp tissue response following direct pulp capping with Clearfil Protect Bond (CPB) self-etching adhesive containing an antibacterial monomer MDPB. The pulps of third molar teeth were exposed by the removal of carious tissue. In an experimental group, CPB was applied to the exposed pulp and dentin. In the control groups, Clearfil SE Bond (CSE) or calcium hydroxide-based cement (CH) was applied to the exposed pulp surfaces. All teeth were filled with resin composite, extracted after 90 days, and the pulp responses were histologically analyzed. No severe inflammation or soft tissue disorganization was observed in CPB and CH groups. CSE group exhibited a disorganized odontoblastic layer and severe inflammatory infiltration. No hard tissue formation was observed in CSE group, and CH formed more of a hard tissue formation than CPB. CPB induced an acceptable healing response when directly applied to exposed pulps with bacterial contamination.

Does Cavity Disinfectant Affect Sealing Ability of Universal Self-etch Adhesive?

The purpose of this study was to evaluate 2% chlorhexidine disinfectant (CHX), chitosan, and octenidine dihydrochloride (as cavity disinfectants) on microleakage in cavities restored with universal self-etch adhesive. Eighty extracted human permanent premolars were selected. Class V cavities were prepared on the facial surface of each tooth. The teeth were then divided into four groups of 20 teeth each. For the control group after cavity preparation, no disinfectant was applied. The other 3 groups were treated with 0.1% chitosan, 2% CHX, and 0.1% octenidine dihydrochloride (OCT). All the groups were restored with universal adhesive followed by composite resin. The teeth were then immersed in 1% methylene blue dye and were sectioned buccolingually. Microleakage was checked under a stereomicroscope on both occlusal and gingival margins. Among all the groups chitosan-treated cavities showed the least microleakage. Chlorhexidine treated cavities showed less leakage as compared to control, OCT group at both the margins. Chitosan as a cavity disinfectant improves the sealing ability of the self-etch adhesive. Furthermore, in vivo studies need to be conducted to examine the interaction and long-term effect of chitosan with the other self-etch adhesive systems. Chitosan a natural polysaccharide can be used as a cavity disinfectant as it improves the sealing ability of self-etch adhesive.

Micro-shear bond strength of resin composite cement to coronal enamel/dentin, cervical enamel, cementoenamel junction and root cementum with different adhesive systems

The cervical area of teeth is the most unpredictable region for durable adhesive bonding. This study evaluated the adhesion potential of resin cement to coronal and cervical/root structures with a focus on enamel, dentin and cementum using etch-and-rinse and self-etch adhesive systems. Anterior teeth (N = 60) were randomly divided into six groups for adhesion tests: (a) unprepared enamel (UE), (b) ground enamel (GE), (c) mid-coronal dentin (D), (d) cervical enamel 2 mm above cementoenamel junction (CE), (e) cementoenamel junction (CEJ), and (f) root cementum (RC). Enamel and dentin surfaces were conditioned using either an etch-and-rinse (Syntac Classic-SY) or self-etch (Clearfil S3 Bond Plus-CS3) adhesive system. Resin cement (Variolink Esthetic) was adhered to the different substrates using polyethylene molds and photo-polymerized. Bonded specimens were stored in water for 24 h at 37 °C. Microshear tests (µSBT) were conducted in a Universal Testing Machine (1 mm/min) and failure types were analyzed after debonding. Data were analyzed using two-way ANOVA and t-test (alpha = 0.05). While substrate type (p < 0.001) and adhesive system (p < 0.001) significantly affected the bond results, interaction terms were not significant (p = 0.063). Within SY adhesive system, adhesion to all substrates were not significant ranging between (8.07 ± 2.39–6.80 ± 4.60) (p > 0.05), except for CEJ (5.19 ± 1.39) and RC (4.08 ± 1.13). With the CS3 adhesive system, all groups presented non-significant results (4.15 ± 1.35–6.04 + 2.38) (p > 0.05), except for D (3.57 ± 1.84) and RC (3.21 ± 1.13) (p < 0.05). µSBT values for D (7.19 ± 2.31) and RC (4.08 ± 1.13) were significantly higher for SY compared to that of CS3 (3.57 ± 1.84–3.21 ± 1.13, respectively) (p < 0.05).

Chitosan improves the durability of resin-dentin interface with etch-and-rinse or self-etch adhesive systems.

Degradation of the dentin-resin interface can occur due to hydrolysis of exposed collagen, resulting in reduced bond strength. This study assessed the effect of dentin treatment with chitosan combined with an etch-and-rinse or self-etch adhesive system on improvement of bond strength and preservation of the interface durability. Methodology Enamel was removed from 80 molars and the teeth were divided into two groups: without chitosan (control) or with 2.5% chitosan gel (1 min). They were further subdivided into two subgroups according to the adhesive system: etch-and-rinse or self-etch. Dentin was restored using a composite resin. Half of the specimens from each restored group were subjected to interface aging and the remaining specimens were used for immediate analysis. The specimens were sectioned and subjected to microtensile bond strength (µTBS) test (n=10), chemical composition testing using Fourier-transform infrared (FTIR) spectroscopy (n=4) and energy-dispersive spectroscopy (EDS) (n=5), and morphological analysis of the adhesive interface using scanning electron microscopy (SEM) (n=5). Data were analyzed using three-way ANOVA.Results Chitosan improved the µTBS of the adhesive interface when compared with the control group (p=0.004). No significant differences were observed in dentin adhesion between the adhesive systems (p=0.652). Immediate µTBS was not significantly different from that after 6 months (p=0.274). EDS and SEM did not show significant differences in the chemical and structural composition of the specimens. FTIR showed a decrease in the intensity of phosphate and carbonate bands after using chitosan.Conclusions Dentin treatment with chitosan combined with an etch-and-rinse or self-etch adhesive system improved the immediate and preserved the 6-month bond strength of the adhesive interface.

Microleakage and characteristics of resin-tooth tissues interface of a self-etch and an etch-and-rinse adhesive systems.

ObjectivesThis study was conducted to compare the microleakage and characteristics of the resin-tooth tissue interface between self-etch and etch-and-rinse adhesive systems after 48 hours and 3 months.Materials and Methods40 extracted premolar teeth were randomly divided into 2 groups: 1-step self-etch adhesive system – Optibond™ All-In-One, and 2-step etch-and-rinse adhesive system - Adper™ Single Bond 2. Both groups were subjected to 500 thermocycles (5°C–55°C) before scanning electron microscope (SEM) analysis or microleakage trial at 48-hour and 3-month time periods.ResultsSEM images showed the hybrid layer thickness, diameter, and length of resin tags of the self-etch adhesive (0.42 ± 0.14 µm; 1.49 ± 0.45 µm; 16.35 ± 14.26 µm) were smaller than those of the etch-and-rinse adhesive (4.39 ± 1.52 µm; 3.49 ± 1 µm; 52.81 ± 35.81 µm). In dentin, the microleakage scores of the 2 adhesives were not different in both time periods (48 hours/3 months). However, the microleakage score of etch-and-rinse adhesive increased significantly after 3 months (0.8 ± 0.63 and 1.9 ± 0.88, p < 0.05).ConclusionsThe self-etch adhesive exhibited better long-term sealing ability in dentin when compared to that of the etch-and-rinse adhesive. The greater hybrid layer thickness and dimensions of resin tags did not guarantee reliable, long-lasting sealing in the bonding area.

Repair Bond Strength of High-viscosity Glass-ionomer Cements Using Resin Composite Bonded with Light- and Self-cured Adhesive Systems.

High-viscosity glass-ionomer cements (HVGICs) used with atraumatic restorative treatment can be repaired with light- or self-cured adhesive systems; however, the repair bond strength of two-step, self-etching and one-step adhesives in the light-cure mode surpass one-step self-cure adhesives. Working on a feasible self-cure approach in the absence of such in rural areas as well as in war zones is of prime importance.

The effect of chlorhexidine primer application on the clinical performance of composite restorations: a literature review

To discuss the effectiveness of chlorhexidine (CHX) used as therapeutic dentin primer in adhesively bonded composite restorations. OVERVIEW: An electronic search in MEDLINE database, accessed through PubMed was conducted. No restrictions of languages and date of publication were made. The following key words were used: "chlorhexidine", "composite" and "composite resins." Clinical studies in which CHX was used during bonding procedures were included in this review. Six studies met the inclusion criteria. Of these, five studies were carried out on noncarious cervical lesions (NCCL). Only one study was carried out on class II preparation of permanent molars. In all studies, either etch-and-rinse and self-etch adhesive systems were used during bonding procedures. On the basis of the reviewed clinical trials, it can be concluded that CHX primer application does not seem to influence clinical outcome of composite restorations. CLINICAL SIGNIFICANCE: Current scientific evidence cannot neither strongly recommend nor discourage the application of CHX as therapeutic primer in composite restorations. Studies with longer follow-up periods with adhesive restorations placed on dentin after caries removal, rather than only on NCCL, are desirable to further investigate the therapeutic effect of CHX during bonding procedures.

Effect of proanthocyanidin on push-out bond strength between fiber post and root dentin- An in-vitro study

Aim: The aim of this study was to assess the influence of Proanthocyanidin (PA) application on bond strength of glass fiber posts to root canal dentin using self-etch adhesive luting system. Materials and Methods: Twenty single rooted mandibular premolars, freshly extracted for orthodontic purpose, were decoronated below the cementoenamel junction, and standardized to 14mm in length. Post space preparation was done upto No 3 Peeso reamer during which canals were irrigated with conventional irrigation protocol. Teeth were randomly divided into two groups (n=20 each) Group 1: Pre-treatment with PA and Group 2 served as the control group. Both Groups were restored with fiber posts bonded with RELYX U200 self-etch adhesive system. Teeth were then stored in distilled water for three months at 37° C. One mm slices were obtained and push-out bond strength testing was performed. Failure patterns were assessed under stereomicroscope at 20x magnification. Results: Individual bond strength values were calculated and statistically analysed with the chi-square test and independent-t-test. A statistically significant difference existed between the two Groups (p

Comparative evaluation of shear bond strength of a dual-cure core build-up composite bonded to dentin using three different self-etch dentin bonding systems - An in-vitro study

Aim: This in-vitro study compared the shear bond strength of a dual-cure core build-up composite bonded to dentin using a two-step self-etch adhesive, with two, single step self-etch universal adhesive systems. Materials and Methods: In the present in-vitro study, sixty extracted permanent human mandibular molar teeth, decoronated below the dentino-enamel junction to expose the coronal dentin, were taken and later mounted in self-cure acrylic resin. The specimens were randomly divided into three groups of twenty samples each, based on the dentin bonding agents used namely ParaBond (a two-step self-etch adhesive) and two one-step universal adhesives i.e. Single Bond Universal and Tetric N-Bond Universal. The dentin surface of samples was treated with the respective adhesives of the groups according to manufacturer’s instructions. The bonded surface was bulk filled using ParaCore dual-cure composite. The attained samples were stored in distilled water at 370C for 24hrs and subsequently put through thermocycling (50C to 550C for 500 cycles). The samples were than subjected to shear loading in Instron Universal testing machine. The data were tabulated and statistically analyzed using analysis of variance (ANOVA) and Tukey’s HSD test. Results: Tetric N-Bond Universal adhesive showed the highest mean Shear Bond Strength (SBS) of 20.78 MPa, followed by Single Bond Universal 19.07 MPa and ParaBond Adhesive 5.44 MPa. Conclusion: Tetric N-Bond Universal showed the highest mean SBS and a predictable relationship was found between the formulation of dentin adhesive systems and their shear bond strength values. Clinical Significance: The universal adhesives showed high shear bond strength as compared to conventional 2-step self-etch adhesives. High acidic pH of self-etch adhesive affected their bond strength. So for stake of bond stability, a mild self-etch / universal adhesive is recommended for adhesion, because higher the bond strength, higher it can withstand the stress