Clinical application and prospects of zirconia bonding agent / 中国组织工程研究

BACKGROUND: Zirconia ceramic was considered as one of the optimal materials in prosthodontics and widely used in daily clinical treatment for its features, such as aesthetic properties, biocompatibility and corrosion resistance. Ideal bond strength and durability are necessary for the restoration to achieve satisfied clinical performance. OBJECTIVE: To systematically review zirconia and common zirconia bonding agents, the physical and chemical properties of zirconia ceramics, the clinical operating process standard, the common zirconia bonding agents and their bonding performance. METHODS: We searched the articles from March 2005 to March 2020 in PubMed, CNKI, Wanfang databases with the key words of “zirconia; surface treatment; universal adhesive; self-adhesive resin cement; bonding strength” in Chinese and English. After screening according to inclusion and exclusion criteria, the final 36 included articles were summarized. RESULTS AND CONCLUSION: Zirconia has excellent physical and chemical properties with hydrophobic surface, so it is difficult to form a proper bonding surface with the substrate. At present, the combination of physical sand blasting and chemical reaction is the most common treatment. The sand blasting can effectively increase the reaction area. In the aspect of chemical bonding, the bond strength of the self-adhesive resin cement can be significantly improved by both the universal adhesive and zirconia primer after 24 hours of water storage; however, the durability of universal adhesive is better than that of zirconia primer. As common sense, 37% phosphoric acid is daily used on tooth surface before bonding procedure, which can prohibit chemical reaction to zirconia. Sand blasting was considered as one of the most practical way to physically increase the surface for 10-MDP contained primers or universal adhesives chemically reacted with zirconia.

Evaluation of Effectiveness of Self-Adhesive Composites for Amalgam Repair with or Without Alloy Primer, in Terms of Shear Bond Strength / Evaluación de la efectividad de los compuestos autoadhesivos para la reparación de amalgamas con o sin imprimación de aleación, en términos de resistencia al cizallamiento

Abstract Purpose: The purpose of the present research was to evaluate the effectiveness of self-adhesive composites in amalgam repair as time-saving alternatives to universal bonding-universal composite materials, with or without the usage of Alloy Primer in terms of shear bond strength. Materials and Methods: Forty- two disc-shaped amalgam samples were prepared by condensing into 6×2 mm holes in acrylic resin blocks, sandblasted with 50 μm Al2O3 and randomly divided into 6 groups according to repair material [Constic (Group C), Fusio Liquid Dentin (Group FLD), Universal bonding+Universal composite (Group Control), Alloy Primer+Constic (Group APC), Alloy Primer+Fusio Liquid Dentin (Group APFLD), Alloy Primer+Universal bonding+Universal composite (Group APControl)]. After shear bond strength test, the fracture modes were determined under a digital microscope. Statistical analysis was performed using one-way analysis of variance and Tukey's post hoc test. Results: The highest shear bond strength values were obtained for Fusio Liquid Dentin, among the three repair materials when Alloy Primer was not applied (p<0.05). Usage of Alloy Primer increased shear bond strength values of the investigated repair materials to amalgam, except Fusio Liquid Dentin. Conclusion: Within the limitations of the present research, it can be concluded that; the investigated self-adhesive composite materials could be time-saving alternatives to the Universal bonding+Universal composite for the purpose of amalgam repair, in terms of shear bond strength. The clinicians could prefer Fusio Liquid Dentin self-adhesive composite material without Alloy Primer application for the purpose of amalgam repair in non-cooperative patients.

Resumen Propósito: El propósito de la presente investigación fue evaluar la efectividad de las resinas compuestas autoadhesivas en la reparación de amalgamas como alternativas que ahorran tiempo con respecto a las resinas compuestas universales de adhesión universal, con o sin el uso de Alloy Primer en términos de resistencia al cizallamiento. Materiales y métodos: Se prepararon 42 muestras de amalgama en forma de disco condensándolas en orificios de 6×2 mm en bloques de resina acrílica, arenadas con 50 μm de Al2O3 y divididas al azar en 6 grupos según el material de reparación [Constic (Grupo C), Fusio Liquid Dentin (Grupo FLD), Adhesivo universal+Resina universal (Grupo Control), Imprimación de aleación+Constic (Grupo APC), Imprimación de aleación+Fusio Liquid Dentin (Grupo APFLD), Imprimación de aleación+Adhesivo universal+Resina universal (Grupo APControl)]. Después de la prueba de resistencia al cizallamiento, los modos de fractura se determinaron bajo un microscopio digital. El análisis estadístico se realizó mediante análisis de varianza unidireccional y la prueba post hoc de Tukey. Resultados: Se obtuvieron los valores de resistencia al cizallamiento más altos para Fusio Liquid Dentin, entre los tres materiales de reparación cuando no se aplicó Alloy Primer (p<0.05). El uso de Alloy Primer aumentó los valores de resistencia al cizallamiento de los materiales de reparación investigados para la amalgama, excepto Fusio Liquid Dentin. Conclusión: Dentro de las limitaciones de la presente investigación, se puede concluir que; los materiales compuestos autoadhesivos investigados podrían ser alternativas que ahorran tiempo con respecto al adhesivo universal+resina universal con el fin de reparar las amalgamas, en términos de resistencia a la cizalladura. Los clínicos podrían preferir el material compuesto autoadhesivo Fusio Liquid Dentin sin la aplicación Alloy Primer con el fin de reparar amalgamas en pacientes poco cooperadores.

Development of novel self-adhesive resin cement with antibacterial and self-healing properties / 华西口腔医学杂志

OBJECTIVE@#This study aimed to develop novel self-adhesive resin cement with antibacterial and self-healing properties. Furthermore, the dentin bonding strength, mechanical properties, self-healing efficiency, and antibacterial property of the developed cement were measured.@*METHODS@#Novel nano-antibacterial inorganic fillers that contain quaternary ammonium salts with long-chain alkyls were synthesized. These fillers were added into self-adhesive resin cement containing self-healing microcapsules at mass fractions of 0, 2.5%, 5.0%, 7.5%, or 10.0%. The dentin shear bonding test was used to test the bonding strength, whereas the flexural test was used to measure the flexural strength and elastic modulus of the cement. The single-edge V-notched beam method was used to measure self-healing efficiency, and human dental plaque microcosm biofilms were chosen to calculate the antibacterial property.@*RESULTS@#The dentin shear bond strength significantly decreased when the mass fraction of the nano-antibacterial inorganic fillers in the novel cement reached 7.5% (P0.1). Resin cement containing 2.5% mass fraction or more nano-antibacterial inorganic fillers significantly inhibited the metabolic activity of dental plaque microcosm biofilms, indicating strong antibacterial potency (P<0.05).@*CONCLUSIONS@#The novel self-adhesive resin cement exhibited promising antibacterial and self-healing properties, which enable the cement to be used for dental applications.

Effects of universal adhesives and resin cement on the shear bond strength of zirconia / 华西口腔医学杂志

OBJECTIVE@#To study the effects of universal adhesives and resin cement on the shear bond strength and durability of zirconia ceramics.@*METHODS@#Zirconia ceramics were sintered into 20 mm×10 mm×10 mm and 10 mm×10 mm×10 mm specimens. The experiment was divided into 12 groups. The two types of specimens were bonded using two variants of resin cement (RelyX Ultimate and Clearfil SAC self-adhesive resin cement), universal adhesives (non-adhesive, Scotchbond uni-versal adhesive, and Clearfil SE One adhesive), and storage conditions (water bath and water bath-thermal cycling). The shear bond strengths were tested, and the fracture morphologies were analyzed.@*RESULTS@#The cement (F=8.41, P<0.01) and adhesive (F=30.34, P<0.01) exerted a significant effect on the shear bond strength of zirconia, whereas storage condition showed no significant effect on this property (F=1.83, P=0.18). The lowest shear bond strength (14.02 MPa±6.86 MPa) was exhibited by the group treated with RelyX Ultimate resin cement, non-adhesive, and water bath-thermal cycling, whereas the highest shear bond strength (54.12 MPa±8.37 MPa) was displayed by the group treated with RelyX Ultimate resin cement, Scotchbond universal adhesive, and water bath-thermal cycling.@*CONCLUSIONS@#Universal adhesives can improve the durability of the bonding of resin cement to zirconia. If non-self-adhesive resin cement is used without a universal adhe-sive, the durability of the bond will be greatly reduced.

The effects of deproteinization and primer treatment on microtensile bond strength of self-adhesive resin cement to dentin / 대한치과재료학회지

The purpose of this study was to evaluate the effects of deproteinization and an additional primer treatment on the microtensile bond strength of a newly developed self-adhesive resin cement to dentin. The occlusal dentin of extracted human third molars was randomly divided into four groups according to the surface treatment: a control (CON) with no treatment; applying a deproteinizing agent (DPT) (5% sodium hypochlorite); using a primer (PRI) (G-CEM ONE Adhesive enhancing primer, GC); and applying a deproteinizing agent and a primer (DPT-PRI). Composite resin blocks with a disk shape (diameter, 10 mm; height, 4 mm) were bonded to the treated dentin using a self-adhesive resin cement (G-CEM ONE, GC). The specimens were sectioned into sticks with a cross-section of 1 mm² and tested to failure in tension mode at a crosshead speed of 1 mm/min. All groups showed a significantly higher microtensile bond strength compared to CON (p0.05). Within the limitations of this study, a deproteinizing agent or specific primer can enhance the microtensile bond strength of the self-adhesive resin cement to dentin. However, it is not recommended to use a primer in combination with the deproteinizing agents.

Effect of post-space irrigation with naocl and caocl at different concentrations on the bond strength of posts cemented with a self-adhesive resin cement

Abstract The aim of this study was to evaluate the effect of post-space irrigation with NaOCl and CaOCl at different concentrations on the bond strength of posts cemented with a self-adhesive resin cement. Eighty premolars were sectioned 14 mm from the apex, and endodontically treated. The root canal filling was partially removed. Specimens were randomly assigned into 8 groups (n=10), according to the irrigant for post-space irrigation: SS - 0.9% saline solution (control group); CHX - 2% chlorhexidine; 1% NaOCl - 1% sodium hypochlorite; 2.5% NaOCl - 2.5% sodium hypochlorite; 5% NaOCl - 5% sodium hypochlorite; 1% CaOCl - 1% calcium hypochlorite; 2.5% CaOCl - 2.5% calcium hypochlorite; and 5% CaOCl - 5% calcium hypochlorite. For each group, irrigation was performed continuously with 2 ml of solution. The post-spaces were dried with paper points (#80), and glass fiber posts were cemented using a self-adhesive resin cement. The specimens were sectioned perpendicularly and the push-out test was performed. Optical microscopy was used to analyze the failure mode. ANOVA and Bonferroni tests analyzed the bond strength data. NaOCl and CaOCl presented similar bond strength regardless the concentration used to irrigate the post-space (p>0.05). SS showed the highest bond strength (11.47 MPa) (p<0.05). Adhesive failures at the cement/dentin interface were predominant (58.33%). Saline solution should be irrigant of choice to irrigate the post-space before fiber post cementation with self-adhesive resin cement. NaOCl and CaOCl negatively affect the bond strength values.

Resumo O objetivo deste estudo foi avaliar o efeito da irrigação do espaço preparado para o pino com NaOCl e CaOCl em diferentes concentrações na resistência adesiva de pinos cimentados com um cimento resinoso autoadesivo. Oitenta pré-molares foram seccionados 14 mm do ápice e endodonticamente tratado. As obturações foram parcialmente removidas. Os espécimes divididos randomicamente em 8 grupos (n=10) de acordo com o irrigante usado para irrigação do espaço preparado para pino: SF - soro fisiológico 0,9% (grupo controle); CHX - clorexidina 2%; NaOCl 1% - hipoclorito de sódio 1%; NaOCl 2,5% - hipoclorito de sódio 2,5%; NaOCl 5% - hipoclorito de sódio 5%; CaOCl 1% - hipoclorito de cálcio 1%; CaOCl 2,5% - hipoclorito de cálcio 2,5%; CaOCl 5% - hipoclorito de cálcio 5%. Para cada grupo, irrigação foi realizada com 2 mL de solução. O espaço preparado para pino foi seco com cone de papel absorvente (#80) e os pinos de fibra foram cimentados com cimento resinoso autoadesivo. Os espécimes foram seccionados perpendicularmente e o teste de push-out foi realizado. Microscopia óptica foi usada para analisar o padrão de falha. Os testes de ANOVA e Bonferroni analisaram os dados de resistência adesiva. NaOCl e CaOCl apresentaram similar resistência adesiva, independentemente da concentração usada para irrigar o espaço preparado para pino (p>0,05). SF apresentou os maiores valores de resistência adesiva (11,47 MPa) (p<0,05). Falhas adesivas na interface cimento/dentina foram predominantes (58,33%). Soro fisiológico deve ser o irrigante de escolha para irrigar o espaço preparado para pino antes da cimentação de pinos de fibra com cimentos resinosos autoadesivos. NaOCl e CaOCl afetam negativamente os valores de resistência adesiva.

Influence of the dentin smear layer trait on the bond strength of the self-adhesive resin cements / 华西口腔医学杂志

OBJECTIVE@#This work aimed to evaluate the influence of smear layer on the bonding effectiveness and durability of the self-adhesive resin cements to dentin.@*METHODS@#A total of 48 fresh caries-free third molars with exposed dentin surface were divided into two groups. The dentin surfaces were treated using a standard grit diamond bur (group A) or further polished using a fine grit diamond bur (group B) and then bonded with either of the two self-adhesive resin cements, namely, Clearfil SA Cement (CSA, Kuraray) and Multilink Speed (MS, Ivoclar Vivadent). After 24 h or 2-year water storage, a microtensile bond strength test was performed.@*RESULTS@#In group A, the dentin surface was rough, the smear layer was thick, and the dentin tubule orifice detritus showed low embolism value. In group B, the dentin surface roughness decreased, the embolism proportion increased, and the smear layer became thin. The initial bonding strengths of CSA and MS in group A were significantly lower than those in group B (P0.05).@*CONCLUSIONS@#The properties of the smear layer and the types of self-adhesive resin cement used affected the bond strength and durability.

Clinical evaluation of retention strength of two different adhesive systems on glass fiber-reinforced posts / 口腔疾病防治

Objective@# To evaluate the clinical effect of two different resin cements on the glass fiber-reinforced posts.@*Methods @# One hundred and thirty-six teeth were randomly divided into two groups, with sixty-eight in each. Group A used Multilink N self-etch system and group B used RelyX Unicem self-adhesive system to bond fiber posts. Follow-up examinations took place at 6, 12 and 24 months after the placement. @*Results @#The success ratios of two groups were all 97% above and there was no significant difference between two groups (P > 0.05). @*Conclusion@#Multilink N self-etch system and RelyX Unicem self-adhesive system all have good effect on glass fiber-reinforced posts bonding.

Research on bond durability among different core materials and zirconia ceramic cemented by self-adhesive resin cements / 华西口腔医学杂志

<p><b>OBJECTIVE</b>This research estimated shear bond durability of zirconia and different substrates cemented by two self-adhesive resin cements (Clearfil SA Luting and RelyX U100) before and after aging conditioning.</p><p><b>METHODS</b>Machined zirconia ceramic discs were cemented with four kinds of core material (cobalt-chromium alloy, flowable composite resin core material, packable composite resin, and dentin) with two self-adhesive resin cements (Clearfil SA Luting and RelyX U100). All specimens were divided into eight test groups, and each test group was divided into two subgroups. Each subgroup was subjected to shear test before and after 10 000 thermal cycles.</p><p><b>RESULTS</b>All factors (core materials, cements, and thermal cycle) significantly influenced bond durability of zirconia ceramic (P<0.00 1). After 10 000 thermal cycles, significant decrease was not observed in shear bond strength of cobalt-chromium alloy luted with Clearfil SA Luting (P>0.05); observed shear bond strength was significantly higher than those of other substrates (P<0.05). Significantly higher shear bond strength was noted in Clearfil SA Luting luted with cobalt-chromium alloy, flowable composite resin core material, and packable composite resin than that of RelyX U100 (P<0.05). However, significant difference was not observed in shear bond strength of dentin luted with Clearfil SA Luting and RelyX U100 (P>0.05).</p><p><b>CONCLUSIONS</b>Different core materials and self-adhesive resin cements can significantly affect bond durability of zirconia ceramic. 
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Tensile Strength of Resin Cements Used with Base Metals in a Simulating Passive Cementation Technique for Implant-Supported Prostheses

Abstract The aim of this study was to analyze the tensile strength of two different resin cements used in passive cementation technique for implant-supported prosthesis. Ninety-six plastic cylinders were waxed in standardized forms, cast in commercially pure titanium, nickel-chromium and nickel-chromium-titanium alloys. Specimens were cemented on titanium cylinders using self-adhesive resin cement or conventional dual-cured resin cement. Specimens were divided in 12 groups (n=8) in accordance to metal, cement and ageing process. Specimens were immersed in distilled water at 37 °C for 24 h and half of them was thermocycled for 5,000 cycles. Specimens were submitted to bond strength test in a universal test machine EMIC-DL2000 at 5 mm/min speed. Statistical analysis evidenced higher tensile strength for self-adhesive resin cement than conventional dual-cured resin cement, whatever the used metal. Self-adhesive resin cement presented higher tensile strength compared to conventional dual-cured resin cement. In conclusion, metal type and ageing process did not influence the tensile strength results.

Resumo O objetivo deste estudo foi analisar a resistência à tração de dois diferentes cimentos resinosos usados na técnica de cimentação passiva de próteses implanto-suportadas. Noventa e seis cilindros plásticos foram encerados em formas padronizadas, fundidos em titânio grau 2 comercialmente puro e ligas de níquel-cromo e níquel-cromo-titânio. Amostras foram cimentadas sobre cilindros de titânio usando um cimento auto-adesivo ou um cimento convencional de dupla polimerização. Os espécimes foram divididos em 12 grupos (n=8) de acordo com o metal, cimento e processo de envelhecimento. Espécimes foram imersos em água destilada a 37 °C por 24 h e metade deles foi termociclado por 5,000 ciclos. Espécimes foram submetidos ao ensaio de tração numa máquina universal de ensaios (velocidade de 5 mm/min). Análise estatística evidenciou maior resistência à tração do cimento auto adesivo do que o cimento convencional de dupla polimerização, independente do metal utilizado. O cimento resinoso auto adesivo apresentou maior resistência à tração do que o cimento convencional de dupla polimerização. O tipo de metal e o processo de envelhecimento não tiveram influência nos resultados.

Análisis de resistencia al desplazamiento de dos cementos de resina, en dentina intrarradicular / Resistance to displacement analysis of two resin cements in intra-root dentin

Resumen: Para cementar un endoposte reforzado con fibra de vidrio se deben de tomar en cuenta varios factores, entre ellos, la selección del agente cementante. Los cementos disponibles en el mercado difieren por la modalidad de aplicación, tiempo de trabajo, polimerización y composición química, por ello es necesario contar con el conocimiento de todas sus características y su comportamiento no sólo clínico sino también en el laboratorio. Hoy en día la evolución de los cementos de resina va encaminada a la simplificación de la técnica con el fin de reducir tiempo y margen de error durante el proceso clínico, sin embargo, previos estudios han demostrado que estos cambios han reducido la fuerza de adhesióna la dentina. Objetivo: El propósito de este estudio es observar el comportamiento de dos agentes cementantes de resina, evaluando su fuerza de adhesión en dentina intrarradicular, el sistema BisCem® de Bisco Inc., el cual es un cemento autoadhesivo dual y el sistema ParaCore® Automix de Colténe/Whaledent; cemento dual que requiere de un agente autoacondicionador y un adhesivo dentinarios de curado químico (ParaBond® de Colténe Whaledent). Material y métodos: Se encapsularon 36 dientes unirradiculares en acrílico y se desgastaron hasta descubrir la dentina intrarradicular, siguiendo las especificaciones del fabricante, se realizaron 18 muestras para cada cemento y después se sometieron a pruebas de cizalla a una velocidad de 1 mm por minuto en una máquina de ensayo universal. Resultados: Se observó que BisCem® presenta una menor fuerza de adhesión que Para- Core® Automix. Después de analizar estadísticamente los resultados a través de la prueba «T¼ de Student, los resultados mostrando una diferencia significativa entre ambos cementos. Conclusión: ParaCore® Automix que requiere previo acondicionado de dentina (ParaBond®) presentan una mayor fuerza de adhesión.

Abstract: Several factors must be taken into account when cementing an endodontic post reinforced with fiberglass, among them we can mention selection of the cementing agent. Market available cements differ with respect to application mode, working time, polymerization and chemical composition. It is therefore necessary to count with sufficient knowledge of all their characteristics and behavior, not only from the clinical approach, but also in the laboratory. The evolution of resin cements is nowadays geared to technique simplificatión so as to decrease time and margin of error during clinical process. Moreover, previous studies have demonstrated that these changes have decreased adhesion force to dentin. Objective: The purpose of the present study was to observe the behavior of two resin cementing agents, assessing their adhesion strength in intra-root dentin: the BisCem®, Bisco Inc. system, formed by a dual selfadhesive cement, and the ParaCore® Automix (Coltene/Whaledent) system which is a dual cement system requiring a chemical curing self-conditioning agent and dentin adhesives (ParaBond® Coltene Whaledent). Material and methods: Thirty six single rooted teeth we encapsulated in acrylic and worn down until reaching intra-root dentin. Following manufacturer´s instructions, 18 samples were executed for each cement, and then in a universal testing device they were subjected to shearing tests (guillotine test) at a speed of 1 mm per minute. Results: It was observed that BisCem® exhibited lesser adhesion force than ParaCore® Automix. After statistically analyzing outcome by means of a «T¼ Student test, results revealed significant difference between both cements. Conclusion: ParaCore® Automix, requiring previous dentin conditioning (ParaBond®), exhibited greater adhesion force.

Effect of GLUMA desensitizer on the retention of full metal crowns cemented with Rely X U200 self-adhesive cement

PURPOSE: Considering the importance of retention in the success and long-term clinical service of fixed partial dentures (FPDs) as well as the existing controversy regarding the effect of GLUMA desensitizer on the retention of full metal crowns cemented with RelyX U200 self-adhesive cement, this study aimed to assess the effect of GLUMA desensitizer on the retention of full metal crowns cemented using RelyX U200. MATERIALS AND METHODS: In this experimental study, 20 sound human premolars were prepared; a 0.5 mm chamfer finish line was prepared above the cementoenamel junction. The teeth were randomly assigned to two groups: a desensitizer group (n = 10, treated with GLUMA desensitizer) and a control (n = 10, no surface treatment). Full metal crowns were fabricated of base metal alloy and had a ring. All crowns were cemented with RelyX U200 and subjected to retention test by using a universal testing machine. The data were analyzed using SPSS version 20 and independent t-test. RESULTS: The mean tensile bond strength was significantly higher in the GLUMA desensitizer group (230.63 ± 63.8 N) compared to the control group (164.45 ± 39.3 N) (P≤.012). CONCLUSION: GLUMA desensitizer increases the tensile bond strength of RelyX U200 self-adhesive cement to dentin.

Effect of dentin pretreatment and curing mode on the microtensile bond strength of self-adhesive resin cements

PURPOSE: The aim was to evaluate the effect of curing mode and different dentin surface pretreatment on microtensile bond strength (microTBS) of self-adhesive resin cements. MATERIALS AND METHODS: Thirty-six extracted human permanent molars were sectioned horizontally exposing flat dentin surface. The teeth were divided into 12 groups (3 teeth/group) according to the dentin surface pretreatment methods (control, 18% EDTA, 10% Polyacrylic acid) and curing mode (self-curing vs. light-curing) of cement. After pretreatment, composite resin blocks were cemented with the following: (a) G-CEM LinkAce; (b) RelyX U200, followed by either self-curing or light-curing. After storage, the teeth were sectioned and microTBS test was performed using a microtensile testing machine. The data was statistically analyzed using one-way ANOVA, Student T-test and Scheffe's post-hoc test at P<.05 level. RESULTS: For G-CEM LinkAce cement groups, polyacrylic acid pretreatment showed the highest microTBS in the self-cured group. In the light-cured group, no significant improvements were observed according to the dentin surface pretreatment. There were no significant differences between curing modes. Both dentin surface pretreatment methods helped to increase the microTBS of RelyX U200 resin cement significantly and degree of pretreatment effect was similar. No significant differences were found regarding curing modes except control groups. In the comparisons of two self-adhesive resin cements, all groups within the same pretreatment and curing mode were significantly different excluding self-cured control groups. CONCLUSION: Selecting RelyX U200 used in this study and application of dentin surface pretreatment with EDTA and polyacrylic acid might be recommended to enhance the bond strength of cement to dentin.

Evaluation of shear-bond strength between different self-adhesive resin cements with phosphate monomer and zirconia ceramic before and after thermocycling / 대한치과보철학회지

PURPOSE: This study compared shear bond strengths of five self-adhesive cements with phosphate monomer to zirconium oxide ceramic with and without airborn particle abrasion. MATERIALS AND METHODS: One hundred zirconia samples were air-abraded (50 microm Al2O3). One hundred composite resin cylinders were fabricated. Composite cylinders were bonded to the zirconia samples with either Permacem 2.0 (P), Clearfil(TM) SA Luting (C), Multilink(R) Speed (M), RelyX(TM) U200 Automix (R), G-Cem LinkAce(TM) (G). All bonded specimens were stored in distilled water (37degrees C) for 24 h and half of them were additionally aged by thermocycling (5degrees C, 55degrees C, 5,000 times). The bonded specimens were loaded in shear force until fracture (1 mm/min) by using Universal Testing Machine (Model 4201, Instron Co, Canton, MA, USA). The failure sites were inspected under field-emission scanning electron microscopy. The data was analyzed with ANOVA, Tukey HSD post-hoc test and paired samples t-test (alpha=.05). RESULTS: Before and after thermocycling, Multilink(R) Speed (M) revealed higher shear-bond strength than the other cements. G-Cem LinkAce(TM) (G) showed significantly lower bond strengths after thermocycling than before treatment (P.05). CONCLUSION: Most self-adhesive cements with phosphate monomer showed high shear bond strength with zirconia ceramic and weren't influenced by thermocycling, so they seem to valuable to zirconia ceramic bonding.

Effect of atmospheric plasma versus conventional surface treatments on the adhesion capability between self-adhesive resin cement and titanium surface

PURPOSE: The aim of this study was to evaluate the effects of atmospheric plasma (APL) versus conventional surface treatments on the adhesion of self-adhesive resin cement to Ti-6Al-4V alloy. MATERIALS AND METHODS: Sixty plates of machined titanium (Ti) discs were divided into five groups (n=12): 1) Untreated (CNT); 2) Sandblasted (SAB); 3) Tribochemically treated (ROC); 4) Tungsten CarbideBur (TCB); 5) APL treated (APL). SEM analysis and surface roughness (Ra) measurements were performed. Self-adhesive resin cement was bonded to the Ti surfaces and shear bond strength (SBS) tests, Ra and failure mode examinations were carried out. Data were analyzed by one-way analysis of variance and chi-squared test. RESULTS: The lowest SBS value was obtained with CNT and was significantly different from all other groups except for APL. The ROC showed the highest SBS and Ra values of all the groups. CONCLUSION: It was concluded that the effect of APL on SBS and Ra was not sufficient and it may not be a potential for promoting adhesion to titanium.

Effect of Surface Treatment of Fiberglass Posts on Bond Strength to Root Dentin

This study evaluated the influence of the surface treatments of fiberglass posts on bond strength to root dentin using push-out test. Forty bovine incisor roots were endodontically treated. The surface of the fiberglass posts (Exacto #2, Angelus) were treated using 4 different protocols (n=10): Control - 70% ethanol for 1 min; 37% phosphoric acid for 1 min; 10% hydrofluoric acid for 1 min; and 24% hydrogen peroxide for 1 min. After a silane coupling agent was applied for 1 min and all posts were cemented using self-adhesive resin cement (RelyX Unicem, 3M-ESPE). The roots were sectioned and two 1-mm-thick slices were obtained from each third: cervical, middle and apical. The specimens were subjected to the push-out test with a crosshead speed of 0.5 mm/min. Data were analyzed by repeated measures ANOVA followed by Tukey's HSD tests (=0.05). The surface treatment (p<0.001) and root third region (p=0.007) factors were significant. The retention to root canal was affected by surface treatment type. The post surface treatment with 24% hydrogen peroxide for 1 min yielded significantly higher bond strength when the fiberglass posts were cemented with RelyX Unicem.

Este estudo avaliou a influência de tratamentos de superfície de pinos de fibra de vidro na resistência de união à dentina radicular por meio do teste de push-out. Quarenta raízes de incisivos bovinos foram submetidas a tratamento endodôntico. A superfície dos pinos de fibra de vidro (Exacto #2, Angelus) foram tratadas com 4 protocolos diferentes (n=10): Controle - 70 % de etanol durante 1 min; 37 % de ácido fosfórico durante 1 min, 10% de ácido fluorídrico durante 1 min e 24 % de peróxido de hidrogênio durante 1 min. Depois foi aplicado agente de união silano por 1 min e todos os pinos foram cimentados com cimento resinoso auto-adesivo (RelyX Unicem, 3M- ESPE). As raízes foram seccionadas e foram obtidas duas fatias de 1 mm de espessura em cada terço: cervical, médio e apical. Os espécimes foram submetidos ao teste de push-out com uma velocidade de 0.5 mm/min. Os dados foram analisados pelo teste ANOVA com medidas repetidas, seguido pelo teste de Tukey HSD (=0,05). Os fatores tratamento de superfície (p<0,001) e região do terço radicular (p=0,007) foram significantes; no entanto, a interação entre os dois fatores não foi significante (p=0,827). A retenção ao canal radicular foi afetada pelo tipo de tratamento de superfície. O tratamento de superfície com 24% de peróxido de hidrogênio por 1 min rendeu significativamente maior resistência de união quando os pinos de fibra de vidro foram cimentados com RelyX Unicem.

The effect of dentin desensitizers and Nd:YAG laser pre-treatment on microtensile bond strength of self-adhesive resin cement to dentin

PURPOSE: The purpose of this study is to evaluate if pre-treatment with desensitizers have a negative effect on microtensile bond strength before cementing a restoration using recently introduced self-adhesive resin cement to dentin. MATERIALS AND METHODS: Thirty-five human molars' occlusal surfaces were ground to expose dentin; and were randomly grouped as (n=5); 1) Gluma-(Glutaraldehyde/HEMA) 2) Aqua-Prep F-(Fluoride), 3) Bisblock-(Oxalate), 4) Cervitec Plus-(Clorhexidine), 5) Smart protect-(Triclosan), 6) Nd:YAG laser, 7) No treatment (control). After applying the selected agent, RelyX U200 self-adhesive resin cement was used to bond composite resin blocks to dentin. All groups were subjected to thermocycling for 1000 cycles between 5-55degrees C. Each bonded specimen was sectioned to microbars (6 mm x 1 mm x 1 mm) (n=20). Specimens were submitted to microtensile bond strength test at a crosshead speed of 0.5 mm/min. Kolmogorov-Smirnov, Levene's test, Kruskal-Wallis One-way Analysis of Variance, and Conover's nonparametric statistical analysis were used (P.05). The microtensile bond strengths of Aqua-Prep F, and Cervitec Plus were similar to each other but significantly lower than the control group (P<.05). Bisblock showed the lowest microtensile bond strength among all groups (P<.001). Most groups showed adhesive failure. CONCLUSION: Within the limitation of this study, it is not recommended to use Aqua-prep F, Cervitec Plus and Bisblock on dentin when used with a self-adhesive resin cement due to the decrease they cause in bond strength. Beside, pre-treatment of dentin with Gluma, Smart protect, and Nd:YAG laser do not have a negative effect.

Resina fluida autoadhesiva utilizada como sellante de fosas y fisuras: estudio de microinfiltración / Self-adhesive flowable composite-resin as a fissure sealant. A microleakage study

Objetivo: Evaluar la capacidad de sellado de una resina fluida autoadhesiva (Fusio Liquid Dentin, Pentron Clinical) utilizada como sellante de fosas y fisuras con distintos acondicionamientos de la superficie de esmalte. Materiales y Métodos: Se seleccionaron 140 terceros molares recientemente extraídos, los que fueron distribuidos aleatoriamente en cuatro grupos (n=35) y recibieron una técnica de acondicionamiento del esmalte y aplicación de un sellante. Se establecieron los siguientes grupos: Grupo 1, grabado ácido y aplicación de sellante (Clinpro, 3M ESPE); Grupo 2, grabado ácido y aplicación de resina autoadhesiva (Fusio Liquid Dentin, Pentron Clinical); Grupo 3, aplicación de resina autoadhesiva; Grupo 4, microarenado del esmalte y aplicación de resina autoadhesiva. Los dientes sellados fueron termociclados (500 ciclos, 5-55°C), y posteriormente sumergidos en solución de nitrato de plata amoniacal por 24 h (pH=14) y luego en revelador radiográfico (GBX, Kodak) por 8h. Posteriormente, los dientes fueron cortados para obtener 2 láminas por diente que fueron observadas bajo magnificación (4x) y analizadas digitalmente para evaluar la microinfiltración y la penetración en la fisura. Los resultados fueron analizados estadísticamente (ANOVA, Dunnett, p<0.05). Resultados: La microinfiltración del Grupo 1 (13.18 +/- 9.25 por ciento) fue significativamente menor que la de los grupos 2, 3 y 4 (p<0.05). La penetración en la fisura en el Grupo 1 (98.92 +/- 2.77 por ciento) fue mayor que en los otros grupos, siendo esta diferencia significativa sólo con el Grupo 4. Conclusión: Fusio Liquid Dentin tiene una capacidad de sellado inferior a la del sellante convencional Clinpro, independiente del acondicionamiento del esmalte que se utilice.

Aim: To evaluate the sealing ability of a self-adhesive flowable composite-resin (Fusio Liquid Dentin, Pentron Clinical) with different conditioning treatments of the enamel surface used as a fissure sealant. Materials and Method: 140 recently extracted human third molars were selected and randomly divided into four groups (n=35). Each group received an enamel conditioning treatment and a sealant application. The following groups were established: Group 1, acid etching and sealant application (Clinpro, 3M ESPE); Group 2, acid etching and self-adhesive flowable composite-resin (Fusio Liquid Dentin, Pentron Clinical); Group 3, self-adhesive flowable composite-resin; Group 4, sandblasting and self-adhesive flowable composite-resin. Sealed teeth were thermocycled (500 cycles, 5-55ºC) and immersed in ammoniacal silver nitrate solution for 24 h (ph=14). After that, the teeth were immersed in radiographic developer solution (GBX, Kodak) for 8 h. Then, the teeth were vertically sectioned to obtain two slides each that were observed under magnification (4x) and digitally analyzed to assess microleakage and sealant penetration. Results were statistically analyzed (ANOVA, Dunnett, p<0.05). Results: Microleakage of Group 1 (13.18 +/- 9.25 percent) was significantly lower than groups 2, 3 and 4 (p<0.05). Group 1 had the highest sealant penetration mean (98.92 +/- 2.77 percent). Conclusion: Fusio Liquid Dentin had a worse sealing ability than Clinpro irrespective of their enamel conditioning treatment when used as a fissure sealant. Among Fusio’s groups, acid etching was the best enamel surface conditioning treatment.

Effects of dentin moisture on the push-out bond strength of a fiber post luted with different self-adhesive resin cements

OBJECTIVES: This study evaluated the effects of intraradicular moisture on the pushout bond strength of a fibre post luted with several self-adhesive resin cements. MATERIALS AND METHODS: Endodontically treated root canals were treated with one of three luting cements: (1) RelyX U100, (2) Clearfil SA, and (3) G-Cem. Roots were then divided into four subgroups according to the moisture condition tested: (I) dry: excess water removed with paper points followed by dehydration with 95% ethanol, (II) normal moisture: canals blot-dried with paper points until appearing dry, (III) moist: canals dried by low vacuum using a Luer adapter, and (IV) wet: canals remained totally flooded. Two 1-mm-thick slices were obtained from each root sample and bond strength was measured using a push-out test setup. The data were analysed using a two-way analysis of variance and the Bonferroni post hoc test with p = 0.05. RESULTS: Statistical analysis demonstrated that moisture levels had a significant effect on the bond strength of luting cements (p Clearfil SA > G-Cem. CONCLUSIONS: The degree of residual moisture significantly affected the adhesion of luting cements to radicular dentine.

Adhesion of 10-MDP containing resin cements to dentin with and without the etch-and-rinse technique

PURPOSE: This study evaluated the adhesion of 10-MDP containing self-etch and self-adhesive resin cements to dentin with and without the use of etch-and-rinse technique. MATERIALS AND METHODS: Human third molars (N=180) were randomly divided into 6 groups (n=30 per group). Conventional (Panavia F2.0, Kuraray-PAN) and self-adhesive resin cements (Clearfil SA, Kuraray-CSA) were bonded to dentin surfaces either after application of 3-step etch-and-rinse (35% H3PO4 + ED Primer) or two-step self-etch adhesive resin (Clearfil SE Bond). Specimens were subjected to shear bond strength test using the universal testing machine (0.5 mm/min). The failure types were analyzed using a stereomicroscope and quality of hybrid layer was observed under a scanning electron microscope. The data (MPa) were analyzed using two-way ANOVA and Tukey's tests (alpha=.05). RESULTS: Overall, PAN adhesive cement showed significantly higher mean bond strength (12.5 +/- 2.3 - 14.1 +/- 2.4 MPa) than CSA cement (9.3 +/- 1.4 - 13.9 +/- 1.9 MPa) (P<.001). Adhesive failures were more frequent in CSA cement groups when used in conjunction with two-step self-adhesive (68%) or no adhesive at all (66%). Hybrid layer quality was inferior in CSA compared to PAN cement in all conditions. CONCLUSION: In clinical situations where bonding to dentin substrate is crucial, both conventional and self-adhesive resin cements based on 10-MDP can benefit from etch-and-rinse technique to achieve better quality of adhesion in the early clinical period.