Shear bond strength of resin cements to human dentin.

OBJECTIVES: The objectives of this in vitro study were (1) to assess the bond strength of the universal cement RelyX Unicem to dentin and to compare it with three conventional resin cements, (2) to test the influence of aging on their bonding capacity and (3) to test the influence of the operator on bonding quality by performing the same test in two different centers. METHODS: 160 third molars, divided into 80 for tests at the University of Zurich (Z) and 80 for tests at the University of Berne (B), were assigned to 2 x 8 subgroups of 10 teeth each. The specimens were prepared with the corresponding bonding agents and acrylic rods were luted either with RelyX Unicem (U), RelyX ARC (A), Multilink (M) or Panavia 21 (P). All specimens were stored in water for 24h (W) and half of the specimens were subjected to 1500 cycles of thermocycling (5 degrees C and 55 degrees C) (T). Bond strength was measured by means of a shear test. RESULTS: After water storage RelyX Unicem exhibited lowest bond strength (UWZ: 9.2+/-1.6 MPa, UWB: 9.9+/-1.2 MPa, AWZ: 15.3+/-6.0 MPa, AWB: 12.2+/-4.3 MPa, MWZ: 15.6+/-3.3 MPa, MWB: 12.4 MPa+/-2.4, PWZ: 13.4+/-2.9 MPa, PWB: 14.9+/-2.6 MPa). Thermocycling affected the bonding performance of all four cements. However, bond strength of RelyX Unicem was least influenced by thermocycling (UTZ: 9.4+/-2.9 MPa, UTB: 8.6+/-1.3 MPa, ATZ: 11.4+/-6.3 MPa, ATB: 13.3+/-3.7 MPa, MTZ: 15.4+/-3.1 MPa, MTB: 10.3+/-2.4 MPa, PTZ: 11.1+/-2.8 MPa, PTB: 11.3+/-2.8 MPa). SIGNIFICANCE: Although the bond strength of RelyX Unicem to dentin was lower in comparison to RelyX ARC, Multilink and Panavia 21, its bond strength was less sensitive to variations in handling and aging.     

2种树脂黏固剂产品与人牙本质黏结性能的研究

目的探讨2种树脂黏固剂对进行和不进行处理的人牙本质是否具有相同的黏结效果。方法将30枚人牙本质试件分为6组,分别施以不同表面的处理（A、B组不处理 C、D组磷酸酸蚀15s E、F组磷酸酸蚀15s后使用One-step通用型黏结剂）。A、C、E组使用RelyX Unicem双固化树脂黏固剂,B、D、F组使用Bis-cem双固化树脂黏固剂,制作牙本质/树脂黏固剂黏结试件,测试剪切黏结强度,扫描电镜观察黏结界面形态。结果统计分析可知组A和组B的黏结强度值分别低于组C、E和组D、F,组C与组E间以及组D与组F间无统计学差别。RelyX Unicem树脂黏固剂除对于磷酸酸蚀牙本质的黏结强度高于Biscem树脂黏固剂外,牙本质进行其他表面处理或不处理时,2种树脂黏固剂间的黏结强度无明显差别。结论磷酸酸蚀能够提高RelyX Unicem和Biscem2种自黏结树脂黏固剂对牙本质的黏结强度。     

Shear bond strength of resin cements to both ceramic and dentin

STATEMENT OF PROBLEM: All ceramic restorations benefit from resin cement bonding to the tooth. However, the literature is unclear on which cement, ceramic conditioning treatment, and dentin bonding agent produce the highest and longest-lasting bond strength. PURPOSE: This in vitro study evaluated immediate and 6-month shear bond strengths between a feldspathic ceramic and 4 different resin cements with the use of 6 different surface-conditioning treatments. Shear bond strengths between the 4 resin cements and dentin also were measured. MATERIAL AND METHODS: Four hundred eighty discs (10 mm in diameter and 4 mm thick) of Ceramco II porcelain were randomly divided into 6 main groups (n = 80). The ceramic specimens received 6 different surface conditioning treatments before the application of resin cement. These surface treatments were sanding with 600-grit silicon carbide paper, microetching with aluminum oxide, sanding followed by silane application, microetching followed by silane application, hydrofluoric acid-etching, and hydrofluoric acid-etching followed by silane application. Each group then was subdivided into 4 subgroups (n = 20) for the application of 1 of 4 cements: Nexus, Panavia 21, RelyX ARC, and Calibra. All cemented specimens were tested under shear loading until fracture on a universal testing machine; the load at fracture was reported in MPa as the bond strength. Bond strengths were determined at 24 hours and after 6 months of specimen storage in a saline solution. For dentin-resin cement shear bond strength testing, dentin specimens were treated with dentin bonding agents, and a thin layer of resin cement was applied according to the manufacturer's directions. Prodigy composite was bonded to the cement. Shear bond strengths were determined as above and reported in MPa at fracture. Data were analyzed with 3-way analysis of variance (P<.01). RESULTS: Hydrofluoric acid-etching followed by silane application produced bond strengths (15.0 +/- 7.4 to 21.8 +/- 5.8 MPa) in the highest statistical group with all 4 cements at both 24 hours and 6 months (P<.01). Sanding with 600-grit silicon carbide paper and microetching with aluminum oxide produced the lowest bond strengths (0.0 to 4.0 +/- 3.5 MPa). At 24 hours and 6 months, there were no significant differences among the 4 cements when hydrofluoric acid-etching was followed by silane application. Both auto- and light-polymerized dentin bonding agents bonded better to dentin than dual-polymerized bonding agents. CONCLUSION: Within the limitations of this study, hydrofluoric acid-etching followed by silane application produced the best bonds at 24 hours and 6 months with all 4 cements. Auto- and light-polymerized adhesives were associated with higher bond strengths to dentin than dual-polymerized adhesives.     

Shear bond strength of dual-cured and self-cured resin composites to dentin using different bonding agents and techniques

This study determined the effects of bonding agents on the shear bond strength of dual- and self-cured resin composites to dentin. Two light-cured dentin bonding agents (Excite and One-Step) and a dual-cured bonding agent (Excite DSC) were compared. Light activation of the bonding agents prior to placement of the resin composites was also evaluated. This in vitro study was performed on 120 extracted non-carious human third molars. The occlusal part of the crowns was removed to expose a flat dentin surface. The teeth were then randomly divided into three major groups for Excite, One-Step and Excite DSC as bonding agents. The specimens in each adhesive group were divided into four subgroups: with and without light activation of the bonding agent and with dual-cured (Luxacore Dualcure, DMG, Hamburg, Germany) or light-cured resin (Luxacore, DMG, Hamburg, Germany) composites. After placing the restorations, the specimens were kept in water at 37 degrees C for 24 hours before being tested for shear bond strength on an Instron universal testing machine at a crosshead speed of 0.5 mm/minute. The results showed that the shear bond strength of dual-cured resin composite to dentin was significantly higher than that of self-cured resin composite (p = 0.017). Light activation of the bonding agents prior to applying the resin composites led to a significantly higher shear bond strength of the resin composites to dentin, compared to no light activation (p < 0.05).     

Shear bond strength of AH-26 root canal sealer to dentine using three dentine bonding agents

OBJECTIVE: The purpose of the study was to compare the bond strength of AH-26 root canal sealer to human root canal dentine exposed to different intracanal medications both with and without the use of three bonding agents. The materials used were AH-26 sealer, two one-bottle bonding agents (Single Bond, Bond-1) and one self-etching bonding agent (Clearfill SE Bond). METHODS: The dentine substrate was obtained from single rooted human teeth. The dentine specimens were treated either with EDTA 15% or phosphoric acid 37% to achieve the removal of smear layer. The AH-26 sealer was placed on the dentine surfaces both with and without the use of the bonding agents. Bond strength was tested using a single plane shear test assembly. RESULTS: The SBS values were (MPa): Group A (EDTA-AH-26) 3.678+/-0.853, Group B (Phosphoric acid-AH-26) 3.470+/-0.834, Group C (EDTA-Single Bond-AH-26) 4.8+/-0.865, Group D (Phosphoric acid-Single Bond-AH-26) 5.043+/-1.022, Group E (EDTA-Bond 1-AH-26) 4.939+/-0.877, Group F (Phosphoric acid-Bond 1-AH-26) 5.101+/-1.117, Group G (Clearfill SE Bond-AH-26) 6.975+/-1.694.The use of dentine bonding agents improved significantly (p<0.05) the adhesion of AH-26 sealer with the root canal dentine. However, the best results were obtained with the self-etching system. Similar results were observed from the pretreatment of dentine either with phosphoric acid 35% or EDTA 15%. CONCLUSIONS: The use of dentine bonding agents gave higher shear bond strengths of AH-26 sealer to human root canal dentine.     

Morphological and bond strength evaluation of different resin cements to root dentin

This study correlated the morphological characteristics with the bond strengths of various resin cements used for bonding fiber posts to root canal dentin. Fifty glass-fiber posts (FRC Postec Plus) were luted into the root canals of extracted human anterior teeth using five resin cements ( n  = 10): Panavia F 2.0, PermaFlo DC, Variolink II, RelyX Unicem, and Clearfil Core. Before insertion of the post, the adhesive systems were labeled with fluorescein and the resin cement was labeled with rhodamine isothiocyanate. The roots were sectioned into three slices (of 2 mm thickness), and each slice was analyzed using confocal laser scanning microscopy in dual fluorescence mode to determine hybrid layer thickness, the number of resin tags, and the number of broken tags. Bond strengths were measured using a micro push-out test. Bond strengths to root canal dentin, as well as the morphological characteristics, were significantly affected by the materials. However, these factors did not correlate. The self-adhesive resin cement, which showed the formation of a hybrid layer and resin tags only sporadically, had the highest bond strengths. These results indicate that chemical interactions between the adhesive cement and hydroxyapatite may be more crucial for root dentin bonding than the ability of the same material to hybridize dentin.     

Shear bond strength of glass-ionomer cements to air-abraded dentin

PURPOSE: The aim of this in vitro study was to evaluate the shear bond strength of two conventional glass-ionomer cements to bovine dentin when using the air-abrasion technique for cavity preparation. MATERIALS AND METHODS: Forty bovine central incisors were selected, embedded in polyester resin, and ground until the dentin surface was exposed. The teeth were randomly assigned to four groups: I and II--rotating instrument with a carbide bur; III and IV--an air-abrasion system. Groups I and III were restored with Fuji IX and groups II and IV with Ketac Molar. A 3-mm-diameter bonding site was delimited and treated with 10% polyacrylic acid for 10 s in the Fuji IX subgroups and with 25% polyacrylic acid for 10 s in the Ketac Molar subgroups. After surface treatment, a glassionomer cylinder was prepared for each specimen, using a split bisected Teflon matrix. The finished specimens were submitted to the shear bond strength test in a universal testing machine at a crosshead speed of 0.5 mm/min. The data were analyzed using ANOVA and Scheffé statistical tests. The dentin bonding areas were analyzed under a stereoscopic optical magnifier (40X) to assess the type of failure. RESULTS: The mean (SD) shear bond strengths in MPa were: group I--3.49 (+/- 3.77), group II--7.17 (+/- 2.93), group III--7.55 (+/- 2.99), group IV--5.67 (+/- 3.90). Ketac Molar showed higher bond strength values in bur-prepared cavities, while on the air-abraded preparations, Fuji IX showed superior results. CONCLUSION: It can be concluded that the air-abrasion system used for cavity preparations may influence the bonding performance of conventional glass-ionomer cements to dentin.     

Factors affecting in vitro bond strength of bonding agents to human dentin

Four generations of total-etch (fourth, fifth) and self-etching (sixth, seventh) bonding agents for use with resin composites are commercially available in the United States. Innovations in bonding agents include: filled systems, release of fluoride and other agents, unit dose, self-cured catalyst, option of etching with either phosphoric acid or self-etching primer, and pH indicators. Factors that can affect in vitro bond strength to human dentin include substrate (superficial dentin, deep dentin; permanent versus primary teeth; artificial carious dentin), phosphoric acid versus acidic primers, preparation by air abrasion and laser, moisture, contaminants, desensitizing agents, astringents, and self-cured restorative materials. This article reviews studies conducted at the Houston Biomaterials Research Center from 1993 to 2003. Results show that in vitro bond strengths can be reduced by more than 50% when bonding conditions are not ideal.     

粘接处理剂对自粘接树脂水门汀和RMGIC的牙本质粘接强度的影响

目的:实验评价牙本质粘接处理剂对自粘接树脂水门汀和树脂加强型玻璃离子水门汀(RMGIC)的牙本质微拉伸粘接强度的影响.方法:选用离体人无龋第三恒磨牙24颗,用低速切片机垂直于牙体长轴方向将磨牙冠(牙合)中1/3交界线处切开待用.实验组牙本质表面涂布牙本质粘接处理剂,对照组不涂粘接处理剂.后将试样分别用自粘接树脂水门汀(Unicem,3M ESPE;seT PP,SDI)或树脂加强型玻璃离子水门汀(Fuji CEM,GC)原位对位粘接.水浴中储存24h后,用低速切片机把样本切割成约1mm×1mm×8mm条状,随后进行微拉伸测试.用扫描电镜观察粘接界面形貌.结果:无论是否使用粘接处理剂,Unicem的牙本质粘接强度显著高于seT PP 和Fuji CEM(P <0.01).与对照组相比,实验组的粘接强度显著提高(P <0.05).结论:粘接处理剂表面处理增强自粘接树脂水门汀及树脂加强型玻璃离子水门汀的牙本质粘接强度.     

Tensile bond strength of indirect composites luted with three new self-adhesive resin cements to dentin

Objective

The aims of this study were to evaluate the tensile bond strengths between indirect composites and dentin of 3 recently developed self-adhesive resin cements and to determine mode of failure by SEM.

Material and Methods

Exposed dentin surfaces of 70 mandibular third molars were used. Teeth were randomly divided into 7 groups: Group 1 (control group): direct composite resin restoration (Alert) with etch-and-rinse adhesive system (Bond 1 primer/adhesive), Group 2: indirect composite restoration (Estenia) luted with a resin cement (Cement-It) combined with the same etch-and-rinse adhesive, Group 3: direct composite resin restoration with self-etch adhesive system (Nano-Bond), Group 4: indirect composite restoration luted with the resin cement combined with the same self-etch adhesive, Groups 5-7: indirect composite restoration luted with self-adhesive resin cements (RelyX Unicem, Maxcem, and Embrace WetBond, respectively) onto the non-pretreated dentin surfaces. Tensile bond strengths of groups were tested with a universal testing machine at a constant speed of 1 mm/min using a 50 kgf load cell. Results were statistically analyzed by the Student''s t-test. The failure modes of all groups were also evaluated.

Results

The indirect composite restorations luted with the self-adhesive resin cements (groups 5-7) showed better results compared to the other groups (p<0.05). Group 4 showed the weakest bond strength (p>0.05). The surfaces of all debonded specimens showed evidence of both adhesive and cohesive failure.

Conclusion

The new universal self-adhesive resins may be considered an alternative for luting indirect composite restorations onto non-pretreated dentin surfaces.     

Shear bond strength of three veneering resins to a Ni-Cr alloy using two bonding procedures

Composite veneering materials are used as alternatives to porcelain in fixed prosthodontics. Mechanical retention of the resin on the metal framework has been associated with the formation of gaps at the resin/alloy interface, and failure of the restoration. Several chemical bonding systems have been introduced to promote resin adhesion. The purpose of the present study was to evaluate the shear bond strength of three photocured composites (Artglass, Solidex & Signum+) to a Ni-Cr alloy.72 wax disks covered with 150-mum diameter beads were cast and divided in two equal groups. In the first group, Metal Photo Primer was applied on the casting surface, while the Siloc system was used in the second. Each group was divided in three subgroups of 12 samples, in which the three composites were photocured. Half of the specimens of each subgroup were subjected to 1000 and 5000 thermal cycles (5 and 55 degrees C) respectively. All specimens were tested in shear in a universal testing machine. The Siloc-Solidex group showed the highest bond strength (17.3 +/- 3.7 MPa). No statistically significant difference was found between specimens treated with Metal Photo Primer or Siloc. Thermocycling did not significantly affect the bond strength values. Solidex showed an adhesive failure mode for both alloy surface treatments, while Artglass and Signum+ exhibited combination failures. Conclusively, the appropriate alloy surface treatment - resin combination can significantly improve the resin-alloy shear bond strength. Specifically, Solidex resin exhibited significantly higher bond values compared with Artglass and Signum+, for both surface treatments and thermocycling procedures.     

Shear bond strength of four filled dentin bonding systems

This study compared the shear bond strength of four filled dentin bonding agents (Prime & Bond NT, One Coat Bond, OptiBond Solo, PermaQuik1) to a conventional unfilled Dentin Bonding agent (3M Scotchbond Multipurpose Plus). A column of composite resin (Herculite XRV Restorative Resin) was bonded to human dentin using the five dentin-bonding systems following the manufacturers' directions. The specimens were thermocycled 1000 cycles from 6 to 60 degrees C. Each specimen was tested on an MTS machine in shear-to-failure. The data were subjected to One-Factor ANOVA and Newman-Kuels post-hoc tests. Statistical analysis revealed that One Coat Bond had significantly greater shear bond strength than all other materials tested.     

两种脱敏剂对牙本质粘接剂粘接强度的影响

目的 探讨两种脱敏剂对牙本质粘接剂粘接强度和微观形态的影响,以期对临床治疗有所指导.方法 将30颗完整且无龋的人第三磨牙去除(牙合)面釉质,采用随机数字表法随机分为3组:C组(对照组)、U组(UltraEZTM处理)和M组(MI Paste处理);每组10颗牙齿.C组不做处理,U组和M组分别使用相应脱敏剂对暴露的牙本质表面进行处理.3组样本牙再各随机分为两个小组,每小组5颗牙,分别用粘接剂A(Single Bond 2)和B(Xeno Ⅲ)粘接,用复合树脂修复达4～5 mm.用慢速锯将牙齿切成粘接面积为0.9 mm×0.9 mm的长方体试件,用微拉伸测试仪测试微拉伸强度,作为粘接强度,对其进行单因素方差分析.每组随机挑选3个试件对粘接界面进行扫描电镜观察.结果 对于粘接剂A,U组粘接强度[(14.58±2.31)MPa]与C组[(15.82±2.18)MPa]的差异无统计学意义(P>0.05),而M组粘接强度[(9.90±0.79)MPa]降低.对于粘接剂B,U组粘接强度[(10.55±1.06)MPa]与C组[(10.73±1.07)MPa]的差异无统计学意义(P>0.05),而M组粘接强度[(8.74±0.87)MPa]降低.扫描电镜见各组混合层均较致密,M组两种粘接剂的树脂突较短且稀少.结论 两种脱敏剂对粘接剂粘接强度的影响不同,U组脱敏剂对全酸蚀和自酸蚀粘接剂的粘接强度无明显影响,而M组脱敏剂可降低两种粘接剂的粘接强度.     

四种树脂水门汀黏结牙本质剪切强度的比较

目的:评价4种树脂水门汀与牙本质黏结剪切强度。方法:新鲜拔除的无龋损人第三磨牙48个,随机分为4组(n=12),制备颊侧牙本质黏结面,分别与4种树脂水门汀(Unicem、Panavia F、VariolinkⅡ、Vitique)黏结处理,测试剪切强度,SEM观察牙本质黏结界面。结果:4种树脂水门汀中RelyX Unicem(12.84±2.29)MPa与Panavia F(14.93±3.73)MPa、Vitique(11.03±2.57)MPa之间无显著性差异(P>0.05),而他们均显著高于VariolinkⅡ(5.43±1.25)MPa(P<0.05)。结论:新型自黏结树脂水门汀RelyX Unicem可以取得与牙本质良好的黏结效果,且美观,易于使用,节省操作时间,为黏结修复体提供了一种新的选择。     

Shear bond strength of composite resin cements to lithium disilicate ceramics

The aim of this study was to evaluate the shear bond strength of different commercial composite resin cement systems to lithium disilicate all-ceramic substrate. Five adhesive resin cement systems Panavia 21 and Panavia F (Kuraray), Variolink 2 (Ivoclar-Vivadent), RelyX Unicem Applicap and RelyX ARC (3M ESPE) were used on all-ceramic (IPS Empress 2; Ivoclar-Vivadent) substrate. Shear bond strength of adhesive resin cement to substrate was tested after thermocycling, or without thermocycling (n = 10). Substrate surfaces of the specimen after loading were SEM microscopically examined. The highest bond strengths in water stored conditions were obtained with RelyX ARC (28.7 +/-3.9 MPa), while in thermocycled conditions the highest bonding values were obtained with Variolink 2 (23.2 +/- 7.5 MPa). The lowest values in both water stored (5.8 +/- 4.0 MPa) and thermocycled (2.4 +/- 2.9 MPa) conditions were obtained with Panavia 21. Shear bond strengths appeared to be affected significantly by thermocycling (anova, P < 0.05). It was concluded that there were significant differences between the bond strengths of adhesive resin cements to lithium disilicate substrate.     

Shear bond strengths of resin adhesive cements to dentin and Ni-Cr-Be alloy.

Two adhesives, Super Bond and Panavia, were evaluated for shear bond strength to dentin. Twenty human teeth were used for each adhesive. Bonding sites were prepared in dentin (600 grit) and the adhesives applied according to the manufacturers' instructions. Bond strengths were determined with an Instron testing machine at 24 hours. Super Bond developed the strongest bond of 21.59 +/- 3.91 MPa. Panavia produced a lower bond strength of 2.68 +/- 1.45 MPa. Statistically, Super Bond was found to have a stronger bond than Panavia. The same two adhesives were applied to Ni-Cr-Be specimens and compared to Comspan. Twenty Rexillium III specimens were used for each adhesive at 24 hours and 20 for thermocycling. The metal specimens were ground flat (600 grit) and then air abraded with 50-micron aluminous oxide. The adhesives were applied to the metal surface in accordance with the manufacturers' instructions. One group was tested at 24 hours while the second group was tested after thermocycling (2,500 cycles at 6 degrees C to 60 degrees C). At 24 hours, Super Bond had a significantly stronger bond than the other materials. Comparison of the 24-hour to thermocycled bond strengths found Comspan had a significant increase in bond strength, Panavia had no significant change and Super Bond had a significant decrease in bond strength. After 2,500 thermocycles, Comspan, Panavia, and Super Bond were not significantly different in bond strength.