A preliminary study of the water movement across dentin bonded to glass-ionomer cements (original) (raw)

Analysis of the bond interface between self-adhesive resin cement to eroded dentin in vitro

PLOS ONE, 2018

The purpose of this study was to evaluate the bonding interface between a self-adhesive resin cement to in vitro eroded dentin. Seventy-two third molars were used and divided into two groups: sound dentin and in vitro eroded dentin. The in vitro erosion was performed following a demineralization protocol, in which the specimens were immersed in a demineralizing solution for 2 minutes per cycle and remineralizing solution for 10 minutes per cycle for 9 days. Both groups were submitted to four dentin surface treatments: control group (without any treatment), 2% chlorhexidine, 20% polyacrylic acid, and 0.1 M EDTA (n = 9). Blocks of resin-based composite were bonded with RelyX U200 self-adhesive resin cement applied on the pretreated dentin surfaces. The teeth were sectioned into beams (1mm 2) and submitted to microtensile bond strength testing to evaluate the bond strength of self-adhesive resin cement to dentin after 24 hours and 8 months of immersion in artificial saliva. Three specimens of each group were longitudinally cut and evaluated using confocal laser scanning microscopy to analyze the dentin/cement interface. Eroded dentin showed higher bond strength values when compared to sound dentin for the 2% chlorhexidine group (p = 0.03), 24 hours after adhesion. When considering eroded dentin, the 0.1M EDTA group showed higher bond strength values with a statistically significant difference only for the control group (p = 0.002). After 8 months of storage, the present results showed that there was no statistically significant difference between the two substrates for all experimental groups (p>0.05). Analysis of the microscopy confocal showed different types of treatments performed on dentin generally increased tags formation when compared to the control group. The eroded dentin showed a significant increase in density and depth of resinous tags when compared to sound dentin. The storage of samples for 8 months seems to have not caused significant degradation of the adhesive interface.

Dentin wetting by four adhesive systems

Dental Materials, 2001

Objectives: To evaluate the dentin wetting by four adhesive systems and to relate the wetting properties with the adhesive ef®ciency. Methods: Scotch Bond Multipurpose Plus (3M), Syntac Single-Component (Vivadent), One-Step (Bisco) and Heliobond (Vivadent) were used. The substrate was super®cial and deep human dentin. Roughness and water contact angle were measured before and after acid etching. Dentin wetting by resins was studied by contact angle measurements as a function of time to evaluate the spreading time. The shear bond strength was evaluated following a single plane method, and the microleakage was evaluated in Class V cavities.

Microtensile Bond Strength and Failure Type Analysis of Self- Etch Adhesive Systems on Superficial and Deep Dentin After Long-term Water Storage

Objective: The aim of this study was to evaluate and compare the microtensile bond strengths of four current adhesive materials that contain different monomers at deep and superficial dentin. Material and Methods: Forty non-carious human third molars (n=5) were used in the study. Specimens were divided into two main groups according to dentin thickness as superficial and deep dentin. Groups were further divided into four subgroups in terms of the adhesive systems used: Nova Compo B Plus (NCBP), Nova Compo B (NCB), Futurabond M (FB) and Clearfil S3 Bond Plus (CS3). All specimens were bonded to resin composite and stored in 37 °C water for 9-months. Teeth were sectioned into 3 x 3 mm thick beams. Microtensile bond strength test was carried out by using a universal testing device (1 mm/min). After fracture, failure types were observed using an optical microscope and the fractured dentin surfaces were observed by a scanning electron microscopy (SEM). One-way ANOVA and Tukey tests were used to compare the adhesive system in each dentin group. An unpaired T-test was used to compare the dentin thickness in each adhesive material. Results: As compared to deep dentin, superficial dentin showed higher µTBS values in groups NCBP, FB and CS, as opposed to group NCB. Only NCB revealed higher bond strength at deep dentin layers when compared to superficial dentin. In the superficial dentin group, NCBP showed the highest bond strength value, RESUMO Objetivo: o objetivo deste estudo foi avaliar e comparar a resistência de união à microtração de quatro materiais adesivos atuais que contêm monômeros diferentes na dentina profunda e superficial. Material e Métodos: Quarenta terceiros molares humanos não cariados (n = 5) foram usados no estudo. Os espécimes foram divididos em dois grupos principais de acordo com a espessura da dentina em superficial e profunda. Os grupos foram subdivididos em quatro subgrupos quanto aos sistemas adesivos usados: Nova Compo B Plus (NCBP), Nova Compo B (NCB), Futurabond M (FB) e Clearfil S3 Bond Plus (CS3). Todos os espécimes foram aderidos à resina composta e armazenados em água a 37 ° C por 9 meses. Os dentes foram seccionados em palitos de 3 x 3 mm de espessura. O teste de microtração foi realizado com o uso de um dispositivo de teste universal (1 mm / min). Após a fratura, os tipos de falha foram observados em microscópio óptico e as superfícies de dentina fraturadas por microscopia eletrônica de varredura (MEV). Os testes ANOVA e Tukey um fator foram usados para comparar o sistema adesivo em cada grupo de dentina. Um teste T não pareado foi usado para comparar a espessura da dentina em cada material adesivo. Resultados: Em comparação com a dentina profunda, a dentina superficial apresentou maiores valores de µTBS nos grupos NCBP, FB e CS, ao contrário do grupo NCB. Apenas NCB revelou maior resistência de união na dentina profunda quando comparada à dentina superficial. No grupo de dentina superficial, NCBP apresentou o maior valor de resistência de união, enquanto NCB apresentou a menor

Dentin adhesives application deviations: Effects on permeability and nanoleakage

Dental Materials Journal

The purpose was to evaluate the effect that deviations from the recommended protocol of a two-step etch-and-rinse adhesive system has on permeability and nanoleakage. One hundred and twenty dentin disks were treated with a two-step etch-and-rinse adhesive system, according to the manufacturer's instructions, or using five simulated deviations from the recommended protocol: applying potassium oxalate, reducing the application time of the adhesive, avoiding adhesive drying, aggressively drying the adhesive, and double application of adhesive. Kruskal-Wallis and Tukey's post hoc comparisons were used to evaluate the permeability reduction (α=0.05). Twelve additional dentin disks were prepared for transmission electron microscope (TEM) analysis of nanoleakage. Aggressive drying, adding additional layers of adhesive or using oxalate reduced dentin permeability and yielded a better infiltration of the hybrid layer, whereas reducing the application time or less drying the adhesive did not to reduce dentin permeability, caused extensive nanoleakage, showing immediate compromised dentin sealing.

Human dentin and the dentin-resin adhesive interface

Acta Materialia, 1998

Dentin, the inner hard tissue of teeth, is a complex hydrated composite and forms the substrate for much of restorative dentistry. Current efforts to improve restorative and preventive dentistry involve the development of effective bonds to this tissue. Modern bonding techniques involve etching the dentin to remove the mineral portion, leaving a collagen network that can be infiltrated with a monomer and polymerized in place to form a mechanical bond. The objective of this study was to investigate the nature of the interfacial zone, called the resin-dentin interdiffusion zone, using scanning electron microscopy for characterization and thickness measurements, X-ray tomographic microscopy for fracture characteristics and atomic force microscopy for the local modulus and hardness variations. 0 1998 Acta Metallurgica

TEM interfacial characterization of an experimental self-adhesive filling material bonded to enamel/dentin

Dental Materials, 2011

A great challenge regarding the ease-of-use of composites involves the development of 'self-adhesive' composites that no longer require a separate adhesive to bond to tooth enamel/dentin. Objectives. To characterize the interfacial ultra-structure of an experimental self-adhesive filling material bonded to enamel and dentin using transmission electron microscopy (TEM). Methods. The experimental self-adhesive material was bonded to bur-cut human enamel and dentin, and to fractured (smear-free) dentin, strictly according to the manufacturers' instructions. The specimens were stored for 1 day in distilled water (37 • C) prior to further common specimen processing for TEM. Results. The experimental self-adhesive filling material revealed a typical micro-hybrid filler distribution. At bur-cut enamel, a tight interface was formed, mostly exhibiting only tiny micro-tags without distinct surface demineralization. At bur-cut dentin, the experimental self-adhesive filling material interacted superficially, with the surface structure being more irregular because of the bur preparation. No clear resin tags were formed due to the obstruction of dentin tubules with smear plugs. At fractured dentin, the formation of a relatively thin hybrid layer of maximum a few hundreds of nanometer was disclosed without clear surface demineralization. Distinct resin tags were formed due to the absence of smear plugs. Silver-nitrate infiltration showed a pattern of spot-like appearance of nano-leakage. Ag deposition was observed more along the dentin-adhesive interface of bur-cut dentin, as compared to that of fractured dentin.

Elemental distributions and microtensile bond strength of the adhesive interface to normal and caries-affected dentin

Journal of Biomedical Materials Research Part B: Applied Biomaterials, 2005

The aim of this study was to evaluate the microtensile bond strength (TBS) and the elemental contents of the adhesive interface created to normal versus caries-affected dentin. Extracted human molars with coronal carious lesions were used in this study. A self-etching primer/adhesive system (Clearfil Protect Bond) was applied to flat dentin surfaces with normal and caries-affected dentin according to the manufacturer's instructions. After 24 h water storage, the bonded specimens were cross-sectioned and subjected to a TBS test and electron probe microanalysis for the elemental distributions [calcium (Ca), phosphorus (P), magnesium (Mg), and nitrogen (N)] of the resin-dentin interface after gold sputtercoating. The TBS to caries-affected dentin was lower than that of normal dentin. The demineralized zone of the caries-affected dentin-resin interface was thicker than that of normal dentin (approximately 3 m thick in normal dentin; 8 m thick in caries-affected dentin), and Ca and P in both types of dentin gradually increased from the interface to the underlying dentin. The caries-affected dentin had lost most of its Mg content. The distributions of the minerals, Ca, P, and Mg, at the adhesive interface to caries-affected dentin were different from normal dentin. Moreover, a N peak, which was considered to be the collagenrich zone resulting from incomplete resin infiltration of exposed collagen, was observed to be thicker within the demineralized zone of caries-affected dentin compared with normal dentin.