Effect of natural cross-linkers incorporation in a self-etching primer on dentine bond strength

Objectives

The aim of this in vitro study was to investigate the effect of incorporation of natural cross-linkers into the primer of a self-etching adhesive on resin–dentine bond strength.

Methods

Flat dentine surfaces were prepared from extracted human molar teeth and were applied with the following self-etching primers. The 0.5% hesperidin (HPN), 0.5% chlorhexidine (CHX) or 0.5% grape seed extract (GSE) was incorporated into Clearfil SE primer (Kuraray Medical, Inc.) to formulate three experimental primers. The original SE primer served as control. Following primer application, the teeth were bonded with Clearfil SE bond, restored with resin composite and stored in water for 24 h at 37 °C. The bonded specimens were sectioned into beams and subjected to micro tensile bond testing (μTBS). Failure analysis and morphological evaluation of the dentine surfaces were performed using a scanning electron microscope (SEM). Hardness (H) and elastic modulus (EM) were measured using nano-indentation technique to examine the mechanical properties of the bonded interfaces.

Results

One-way ANOVA showed significant differences in μTBS, H and EM among the tested and control groups (p < 0.001). Tukey post hoc test revealed that incorporation of HPN significantly increased μTBS, H and EM, when compared with the other groups (p < 0.006). The GSE-incorporated group significantly decreased μTBS, H and EM, when compared with the other groups (p < 0.006); while CHX-incorporated group did not show any statistical significant difference when compared with the control group.

Conclusion

Incorporation of HPN into Clearfil SE primer had a positive influence on the immediate μTBS and mechanical properties of the bonded interface.     

Effect of 2% chlorhexidine on dentin microtensile bond strengths and nanoleakage of luting cements

Objectives

The aim of this study was to investigate the effect of pre-treatment by chlorhexidine on the microtensile bond strength (mTBS) of resin cements and nanoleakage at the resin–dentine interfaces.

Methods

Cylindrical composite blocks were luted to human dentine using resin cements (RelyX ARC, 3M ESPE: ARC; Panavia F, Kuraray Medical Inc.: PF; RelyX Unicem, 3M ESPE: UN) with/without pre-treatment by 2% chlorhexidine digluconate (CAVITY CLEANSER, Bisco, Inc., Schaumburg, IL, USA). CAVITY CLEANSER was applied on the acid etched dentine for 60 s in the ARC group, and on smear layer-covered dentine in the PF and UN groups. After storage in water for 24 h, the bonded teeth were sectioned into 1 mm thick slabs and further into 0.9 mm × 0.9 mm beams. After immersion in water or ammoniacal silver nitrate for 24 h, the beams were stressed to failure in tension. The fractured surfaces were examined by field-emission scanning electron microscopy (FE-SEM) using backscattered electron mode. The silver-stained slabs were used to examine nanoleakage within the bonded interface by FE-SEM.

Results

The resin cement and chlorhexidine treatment had significant effects (p < 0.0001) on mTBS; while the storage media had no significant effect (p = 0.435). The mTBS of ARC was significantly higher than the other cements. Chlorhexidine reduced mTBS and produced pronounced nanoleakage when PF and UC were luted to dentine.

Conclusions

Pre-treatment with chlorhexidine affected the integrity of dentine bonding with PF and UC, while there was no adverse effect on coupling of ARC.     

Bracket bond strength comparison between new unfilled experimental self-etching primer adhesive and conventional filled adhesives

Objective:To determine if a new unfilled experimental self-etching primer (SEP) adhesive system (SBP-40TX + C&B Metabond) that incorporates a methyl methacrylate–based 4-META/TBB (4-methacryloxyethyl trimellitate anhydride tri-n-butyl borane) resin can provide adequate shear bond strength (SBS) when used for bonding orthodontic brackets.Methods and Materials:Forty-eight human maxillary premolars were randomly divided into three groups of 16 specimens each. Brackets were bonded with three bonding systems. A filled Bis-GMA/TEGDM (triethylene glycol dimethacrylate)–based SEP adhesive system (Transbond Plus) and an unfilled conventional etch-and-rinse adhesive system (C&B Metabond) were used for comparison. The SBS for each sample was examined with a universal testing machine, and the Adhesive Remnant Index score was calculated. Enamel surfaces after conditioning were examined using a scanning electron microscope. Data were compared by one-way analysis of variance and a χ² test.Results:The experimental SEP showed a milder etching pattern than Transbond Plus SEP. No statistically significant differences in the mean SBS were found between the specimens bonded with the unfilled experimental SEP adhesive system (10.0 MPa) and the filled SEP adhesive system (8.7 MPa). The unfilled experimental SEP adhesive system showed less residual adhesive than the filled SEP adhesive system.Conclusions:The unfilled experimental SEP adhesive system showed a clinically sufficient SBS that was equivalent to the filled SEP adhesive system.     

The incorporation of chlorhexidine in a two-step self-etching adhesive preserves dentin bond in vitro

Objectives

To investigate whether the incorporation of chlorhexidine in a two-step self-etching adhesive can preserve dentin bond strengths.

Methods

Different amounts of 20% chlorhexidine digluconate were added directly to the primer of Clearfil SE Bond to prepare mixtures of four different concentrations of chlorhexidine: 0.05%, 0.1%, 0.5% and 1.0%. Sixteen extracted third molars were randomly divided into 4 groups. Each group corresponded to one of the four chlorhexidine concentrations. Each of the 16 teeth was sectioned into two halves. One half was bonded with Clearfil SE Bond without chlorhexidine, and the other half was bonded with Clearfil SE Bond containing different concentrations of chlorhexidine. Specimens were stored in 0.9% NaCl containing 0.02% sodium azide at 37 °C. Microtensile bond strengths were tested 24 h after specimen preparation or 12 months later. The modes of fractures were examined under a stereomicroscope.

Results

Twelve-month storage resulted in significant bond strength reduction of all control groups (p < 0.05). When incorporated in SE Bond primer, chlorhexidine preserved dentin bond in the 0.1%, 0.5% and 1.0% chlorhexidine group (p < 0.05); in the 0.05% group, there is no statistical difference of bond strength between control group and experimental group tested at the 12-month period (p > 0.05).

Conclusions

When incorporated in the primer of Clearfil SE Bond, chlorhexidine can preserve dentin bond as long as the concentration of chlorhexidine in the primer is higher than or equal to 0.1%.     

Effect of saliva contamination on bond strength of resin luting cements to dentin

Objectives

This study examined the effect of saliva contamination on the microtensile bond strength (μTBS) of resin luting cements to dentin.

Methods

For RelyX ARC (ARC, 3M ESPE), dentin surfaces were etched with 32% phosphoric acid. The subgroups were: ARC-control (uncontaminated), ARC-I (saliva contamination, blot-dried), ARC-II (saliva contamination, rinse, blot-dried) and ARC-III (saliva contamination, rinse, re-etch, rinse, blot-dried). For Panavia F 2.0 (PF, Kuraray), the subgroups were: PF-control (uncontaminated), PF-I (saliva contamination, dried), PF-II (saliva contamination, rinse, dried), PF-III (primer, saliva contamination, dried), PF-IV (primer, saliva contamination, dried, primer re-applied) and PF-V (primer, saliva contamination, rinse, dried, primer re-applied). Composite blocks were luted onto dentin using the two cements. Bonded specimens were sectioned into 0.9 mm × 0.9 mm beams for μTBS testing. Representative fractured beams were prepared for fractographic analysis.

Results

For ARC, salivary contamination of etched dentin (ARC-I) significantly lowered bond strength (p = 0.001). Rinsing saliva off with water (ARC-II) restored bond strength to control level. Re-etching dentin surface after rinsing (ARC-III) resulted in the lowest bond strength (p < 0.001). For PF, salivary contamination of dentin before (PF-I) and after application of primer (PF-III and PF-IV) significantly lowered bond strength (p < 0.001). Rinsing saliva off with water and re-application of primer (PF-II and PF-V) improved bond strength.

Conclusion

Saliva contamination during luting deteriorated the bond quality of resin cements. Decontamination by rinsing with water was most effective in restoring the bond strength of RelyX ARC. Decontamination by water-rinsing and primer re-application after rinsing improved the bond strength of Panavia F 2.0.     

The effect of several dentin desensitizers on shear bond strength of adhesive resin luting cement using self-etching primer

Objectives

Dentin desensitizers can inhibit the bonding between dentin and resin cements. This study examined the effect of the previous application of desensitizers on the shear bond strength of one resin cement using self-etching primer to dentin.

Materials and methods

One hundred and twenty-five dentin exposed teeth were randomly assigned to four experimental groups and one control group of 25 teeth each. Four dentin desensitizers were applied to the four experimental groups, respectively. The dentin desensitizers used were SuperSeal^® (Phoenix Dental, Inc., USA), MS-Coat^® (Sun Medical Co. Ltd, Japan), Gluma^® (Heraeus Kulzer, Germany), and Copalite Varnish^® (Cooley &; Cooley Ltd, USA). Panavia F (Kuraray Co. Ltd, Tokyo, Japan) was attached to the top of each experimental and control group teeth using an Ultradent testing jig (Ultradent Product, Inc., Utah, USA), and the shear bond strength was measured using a Universal testing machine (Model 6022, Instron Co., Canton, MA, USA). The tooth surface was examined by scanning electron microscopy (SEM, JSM-T2000, JEOL, Tokyo, Japan).

Results

The control group showed the greatest shear bond strength (14.74 MPa) followed by SuperSeal^® (12.33 MPa), Gluma^® (5.28 MPa), MS-Coat^® (4.44 MPa) and Copalite Varnish™ (3.14 MPa). There was no significant difference in shear bond strength between the control group and the experimental group treated with Superseal^®. The shear bond strength in the other experimental groups treated with Gluma^®, Varnish^®, and MS-Coat^® was similar to each other but significantly lower than control or Superseal^®. SEM showed revealed resin tags in most of the dentinal tubules in the experimental group treated with the Superseal^®.

Conclusion

Among the four dentin desensitizers, Superseal^® was the only one that did not interfere with the process of resin bonding. The other dentin desensitizers that contained a resin ingredient interfered with resin retention.     

氯己定预处理牙本质后对自酸蚀粘接剂粘结效果的影响

目的 评价2%氯己定在不同作用时间下对自酸蚀粘接剂稳定性的影响。方法 选择50颗无龋离体牙作为研究对象,制作牙本质试件,采用Adper^TM Easy One自酸蚀粘接剂粘结,堆积复合树脂,制作粘结试件。试件分别用2%氯己定进行0、15、30、45、60 s预处理,分别在老化循环前后进行微拉伸强度和扫描电镜测试,检测氯己定对自酸蚀粘结的影响。采用SPSS 19.0软件包对数据进行统计学分析。结果 氯己定预处理45、60 s组即刻测试微拉伸强度显著高于对照组,老化循环后氯己定预处理60 s组微拉伸强度较对照组高,差异显著(P<0.05)。结论 2%氯己定能提高自酸蚀粘接剂的粘结强度,改善粘结界面的老化退变,提高粘结的持久性。     

Influence of cement thickness on resin-zirconia microtensile bond strength

PURPOSE

The aim of this study was to evaluate the influence of resin cement thickness on the microtensile bond strength between zirconium-oxide ceramic and resin cement.

MATERIALS AND METHODS

Thirty-two freshly extracted molars were transversely sectioned at the deep dentin level and bonded to air-abraded zirconium oxide ceramic disks. The specimens were divided into 8 groups based on the experimental conditions (cement type: Rely X UniCem or Panavia F 2.0, cement thickness: 40 or 160 µm, storage: thermocycled or not). They were cut into microbeams and stored in 37℃ distilled water for 24 h. Microbeams of non-thermocycled specimens were submitted to a microtensile test, whereas those of thermocycled groups were thermally cycled for 18,000 times immediately before the microtensile test. Three-way ANOVA and Sheffe''s post hoc tests were used for statistical analysis (α=95%).

RESULTS

All failures occurred at the resin-zirconia interface. Thermocycled groups showed lower microtensile bond strength than non-thermocycled groups (P<.001). Differences in cement thickness did not influence the resin-zirconia microtensile bond strength given the same resin cement or storage conditions (P>.05). The number of adhesive failures increased after thermocycling in all experimental conditions. No cohesive failure was observed in any experimental group.

CONCLUSION

When resin cements of adhesive monomers are applied over air-abraded zirconia restorations, the degree of fit does not influence the resin-zirconia microtensile bond strength.     

Effect of time on tensile bond strength of resin cement bonded to dentine and low-viscosity composite

OBJECTIVES: The purpose of this study was to evaluate the tensile bond strength (TBS) of Panavia F resin cement (PF) applied on dentine pre-treated with ED Primer (ED) and Clearfil Liner Bond 2V (CLB) coated with a layer of low-viscosity composite Protect Liner F (PLF) at 10 min, 24 h and 12 months after curing. METHODS: The labial surfaces of 60 bovine lower incisors were ground to obtain a flat dentine surface, allowing a demarcation of a 4.0 mm-diameter area with adhesive tape. The teeth were randomly divided in six groups; ED was applied in groups A I, A II and A III and CLB was applied, followed by PLF, in groups B I, B II and B III. A resin composite rod with a wire loop was luted directly to the prepared surface of each group with PF. The specimens of groups A I and B I were submitted to TBS test after 10 min. Groups A II and B II were submitted to TBS test after 24 h storage and groups A III and B III were submitted to TBS test after 12 months storage. Each specimen was inspected by SEM and classified according to the failure mode. Additionally, two representative specimens of each failure mode were sectioned for a composite/dentine interface SEM evaluation. RESULTS: No significant statistical differences were observed among the groups at 10 min and 24 h. Groups A III and B III presented the lowest TBS values (p<0.05) after 12 months storage. PF on resin-coated dentin (PLF) showed the highest TBS values and was statistically different to PF on dentine for all the groups. The fracture pattern was generally cohesive on the adhesive/hybrid layer for groups A I, A II and A III and cohesive on composite resin for B I, B II and B III. SIGNIFICANCE: The use of a less hydrophilic self-etching system to pre-treat dentine, coating with a low-viscosity composite layer prior luting with resin cement, may provide a protection of the hybridised complex, allowing a dentine seal during the 12 months storage period.     

底涂剂的化学处理对二氧化锆陶瓷树脂粘接效果的影响

目的 评估专用底涂剂的化学处理对二氧化锆陶瓷与自粘接型树脂水门汀间粘接效果的影响。方法 2.5 mm厚可切削二氧化锆陶瓷片（Vita InceramYZ）经烧结、研磨、清洗后,一半的陶瓷试件表面在0.3 MPa压力下接受50 μm Al2O3颗粒喷砂处理20 s。使用X射线荧光光谱仪对研磨和喷砂组的陶瓷表面成分进行定性定量分析。研磨和喷砂组的陶瓷片各分为2组：一组直接与自粘接型树脂水门汀（Biscem）进行粘接,另一组经底涂剂（Z Primer Plus）处理后与Biscem进行粘接。各实验组试件再分为两个亚组（n=10）经0、10000次冷热循环后接受剪切粘接 强度测量。使用多因素方差分析对数据进行统计。结果 喷砂后的陶瓷表面会有质量比为8.27%的Al2O3颗粒附着。 与喷砂处理相比,底涂剂处理对冷热循环前粘接强度的提高更加显著。冷热循环前后,未经过底涂剂处理的陶瓷与 树脂间粘接强度的差异无统计学意义（P>0.05）,但经过底涂剂处理后陶瓷与树脂间粘接强度的差异有统计学意义（P<0.05）。结论 底涂剂的化学处理能够显著提高二氧化锆陶瓷与自粘接型树脂水门汀的初期粘接强度,但在耐 久实验条件下其粘接界面不稳定,会出现快速老化。     

氯已定预处理对两步法自酸蚀粘接剂牙本质粘接界面稳定性的影响

目的：探讨氯已定预处理对两步法自酸蚀粘接剂的牙本质粘接界面稳定性的影响.方法：40颗离体人磨牙沿垂直于牙长轴的方向切割,暴露冠中部牙本质作为粘接面,牙本质试件随机分为两组,一组在粘接处理前涂布0.2％氯已定为实验组,一组无预处理为对照组,两组经两步法自酸蚀粘接剂SE Bond处理后,堆积复合树脂制备成粘接试件.每组随机抽取2个试件借助微拉曼光谱仪分析粘接剂的双键转化率,剩余的18个试件随机分为两个亚组,分别于即刻和冷热循环5000次后检测微拉伸粘接强度和界面的纳米渗漏情况.结果：0.2％氯已定预处理对SE Bond的树脂双键转化率无显著性影响（P＞0.05）.即刻测试时,对照组和实验组间的微拉伸粘接强度和纳米渗漏差异无统计学意义（PP ＞0.05）.冷热循环老化处理后,实验组的微拉伸粘接强度显著高于对照组,纳米渗漏程度显著低于对照组（P＜0.05）.结论：0.2％氯已定预处理不会干扰SE Bond的树脂聚合,且可提高其与牙本质粘接界面的稳定性.     

氧化锆陶瓷与三种树脂粘接剂粘接剪切强度比较

目的探讨适合牙科氧化锆陶瓷的粘接材料。方法将烧结后的氧化锆陶瓷片分为3组,每组32片,分别采用三种自酸蚀粘接剂RelyX Unicem、PanaviaTM F、Superbond C﹠B与喷砂后的氧化锆陶瓷片粘接,水浴24h和水浴30d后,测试其粘接剪切强度。数据用SAS9.12软件进行统计学分析,粘接断面用扫描电镜观察。结果 PanaviaTMF树脂粘接材料粘接强度最好,分别为（31.36±3.49）MPa（水浴24h）、（29.52±3.44）MPa（水浴30d）。Superbond C﹠B能够取得较好的初期粘接强度（31.85±3.61）MPa（水浴24h）,但水浴30d后明显下降至（21.32±2.58）MPa,P〈0.05。RelyX Unicem的初期（水浴24h）粘接强度最小为（13.29±3.05）MPa,P〈0.0001,但水浴30d后粘接强度为（12.06±2.28）MPa,未见明显降低,P（0.05。结论含有MDP磷酸单体的树脂粘接材料可以使牙科氧化锆陶瓷获得最好的粘接效果。使用不含无机填料的化学固化型纯树脂粘接剂可以取得较好的初期粘接强度但长期效果欠佳。一步法自酸蚀树脂粘接剂虽然没有很高的初期粘接强度,但粘接效果尚能持久。     

Effect of temporary cements on the microtensile bond strength of self-etching and self-adhesive resin cement

Objective. The aim of this study was to evaluate the microtensile bond strength (µTBS) of self-etching and self-adhesive resin cement systems to dentin affected by the presence of remnants of either eugenol-containing or eugenol-free temporary cements. Materials and methods. Thirty extracted teeth were obtained and a flat dentin surface was exposed on each tooth. Acrylic blocks were fabricated and cemented either with one of two temporary cements, one zinc oxide eugenol (ZOE) and one eugenol free (ZOE-free), or without cement (control). After cementation, specimens were stored in water at 37°C for 1 week. The restorations and remnants of temporary cements were removed and dentin surfaces were cleaned with pumice. Resin composite blocks were cemented to the bonded dentin surfaces with one of two resin cements, either self-etching (Panavia F 2.0) or self-adhesive (RelyX U-100). After 24 h, the specimens were sectioned to obtain beams for submission to µTBS. The fracture mode was evaluated under a stereoscopic loupe and a scanning electron microscope (SEM). Data from µTBS were submitted to two-way repeated-measure ANOVA and the Tukey test (alpha = 0.05). Results. The cross-product interaction was statistically significant (p < 0.0003). The presence of temporary cements reduced the bond strength to Panavia self-etching resin cements only (p < 0.05). Fracture occurred predominantly at the dentin–adhesive interface. Conclusions. The presence of eugenol-containing temporary cements did not interfere in the bond strength to dentin of self-adhesive resin cements.     

Clinical bond failure rates of adhesive precoated self-ligating brackets using a self-etching primer

Objective:To comparatively assess the failure rate of adhesive precoated (APC) self-ligating metal brackets bonded with two different enamel surface preparation techniques: self-etching primer (SEP) and conventional two-step etch and primer method (CM).Materials and Methods:Fifty-seven patients with complete permanent dentition were included in this study. A total of 1140 APC self-ligating brackets (3M Unitek, Monrovia, Calif) were bonded using a split-mouth design. For each patient, SEP (Transbond Plus SEP, 3M Unitek) and CM (37% phosphoric acid) were used in alternate quadrants. All brackets were bonded by the same investigator after pumicing and rinsing of all of the teeth. The number, site, and date of first-time bracket failures were monitored throughout orthodontic treatment (mean, 22 months). The survival rates of the brackets were estimated by Kaplan-Meier and log-rank tests (P < .05). The adhesive remnant index was used to determine the bond failure interface.Results:The bond failure rates were 2.97% and 2.18% for the CM and SEP, respectively. No statistically significant difference in failure rates was found between the groups. The bond failure sites were predominantly at the enamel-adhesive interface in both groups.Conclusion:This long-term in vivo study showed that the combined use of SEP and the APC bracket system can be used effectively for bonding brackets after pumicing the enamel surfaces in clinical orthodontics.     

3种粘接材料与氧化锆陶瓷粘接抗剪切强度的比较

目的研究3种粘接材料与氧化锆陶瓷材料的初期及耐久粘接抗剪切强度。方法将预烧结氧化锆陶瓷片试件喷砂后分为3组,每组20个,分别采用玻璃离子水门汀(GIC组)、Panavia F 2.0树脂粘接剂(PF组)、Clearfil SA Luting树脂粘接剂(SAC组)与核树脂块粘接,每组随机选取10个试件进行冷热循环实验(10 000次,5～55℃),用计算机控制万能材料试验机测定其粘接抗剪切强度。结果未经冷热循环处理的GIC组、PF组、SAC组试件的粘接抗剪切强度值分别为(21.98±1.78)MPa、(30.26±1.73)MPa、(28.63±2.02)MPa,GIC组试件的粘接抗剪切强度低于其他两组(P<0.01),PF组与SAC组的试件相比差异无统计学意义(P>0.05);而冷热循环后,GIC组、PF组、SAC组试件的粘接抗剪切强度值分别为(10.72±2.03)MPa、(28.50±1.54)MPa、(27.02±1.79)MPa,GIC组试件经冷热循环后,其粘接抗剪切强度值明显下降(P<0.05),而其他两组试件经冷热循环后其粘接抗剪切强度值无明显改变(P>0.05)。结论使用玻璃离子可获得较好的初期粘接抗剪切强度,但耐久粘接强度欠佳;含磷酸酯单体的树脂粘接剂可使氧化锆陶瓷获得良好的初期粘接抗剪切强度及耐久粘接抗剪切强度;自粘接型树脂粘接剂操作简便,粘接抗剪切强度与自酸蚀型树脂粘接剂相当,且粘接效果持久。     

4种黏结材料与氧化锆陶瓷黏结剪切强度的比较

目的:探讨适合牙科氧化锆陶瓷的黏结材料。方法:将烧结后的氧化锆陶瓷片分为4组,每组16片,分别采用RelyXTM ARC、PanaviaTM F、RelyXTM Luting、Fuji plus4种黏结材料与喷砂后的氧化锆陶瓷片黏结,水浴24h和水浴30d后,测试其黏结剪切强度,数据用SAS6.12软件进行统计学分析,黏结断面用扫描电镜观察。结果:PanaviaTMF树脂黏结材料黏结强度最好,分别为(34.7±3.44)MPa(水浴24h)、(31.5±3.44)MPa(水浴30d),与其他组黏结强度差别有统计学意义(P<0.01)。RelyXTM Luting,Fuji plus2种树脂改良型玻璃离子可以获得较好的初期(水浴24h)黏结强度,分别为(15.5±2.71)MPa和(16.0±1.77)MPa,但水浴30d后明显下降至(6.80±1.24)MPa和(3.38±2.32)MPa,P<0.05。结论:含有MDP磷酸单体的树脂黏结材料可以使牙科氧化锆陶瓷获得最好的黏结效果,使用树脂改良型玻璃离子可以产生较好的初期黏结强度,但黏结效果不能持久。     

树脂加强型玻璃离子粘固剂粘结强度的研究

目的 检测树脂加强型玻璃离子粘固剂的粘结强度,探讨影响粘结性能的相关因素.方法 30颗健康离体前磨牙分成两组,分别用京津釉质粘合剂和树脂加强型玻璃离子粘固剂初次、二次粘接托槽,测剪切强度及粘结剂残余指数.结果 树脂加强型玻璃离子粘固荆的粘结强度与临床普遍使用的京津釉质粘合剂的粘结强度相近,差异无显著性(P>O.05).结论 树脂加强型玻璃离子粘固剂可以替代复合树脂粘结剂.能够满足临床需要.     

Nd：YAG激光对自酸蚀粘结系统和牙本质粘结力的影响

目的探讨Nd：YAG激光对牙本质自酸蚀粘结系统的影响。方法选用因正畸拔除的新鲜前磨牙42颗，随机分为3组，每组14颗；牙面预备暴露牙本质；分别采用Adper^TM Prompt^TM粘结剂＋F2000树脂充填，Nd：YAG激光照射＋Adper^TM Prompt^TM粘结剂＋F2000树脂充填，Adper^TM Prompt^TM粘结剂＋Nd：YAG激光照射＋F2000树脂充填。评价各组树脂与牙本质之间剪切强度。结果Nd：YAG激光照射＋Adper^TM Prompt^TM粘结剂＋F2000树脂充填组的剪切强度明显大于其余2组，其余2组之间剪切强度对比无明显差异。结论先采用脉冲Nd：YAG激光照射后使用Adper^TM Prompt^TM粘结剂组获得最大粘结力。     

自酸蚀树脂水门汀ResiCem牙本质粘结强度的评价

目的 评价自酸蚀树脂水门汀ResiCem的牙本质粘结强度并探讨酸蚀对其粘结强度的影响。方法 选择离体无龋第三恒磨牙15颗。沿垂直于牙体长轴方向将磨牙冠中1/3处切开,将牙本质面分别用自酸蚀树脂水门汀Panavia F和Resi-Cem原位对位粘结。其中ResiCem组牙本质面分别用磷酸酸蚀0、5、10、15 s。用低速切片机把样本切割成约1 mm×1 mm×8mm条块后进行微拉伸测试,并通过扫描电镜观察粘结界面。结果 ResiCem的牙本质微拉伸粘结强度[(16.9±5.3)MPa]与Panavia F[(17.0±5.2)MPa]间差异无统计学意义(P>0.05)。磷酸酸蚀显著地降低ResiCem与牙本质间的粘结强度(P<0.05),并随着酸蚀时间的延长而降低。结论 ResiCem的牙本质微拉伸粘结强度与Panavia F相当,但酸蚀会降低ResiCem的牙本质粘结强度。     

氧化物陶瓷与3种树脂水门汀初期粘接强度比较

目的:通过对2 种修复用氧化物陶瓷与3 种树脂水门汀的粘接抗剪强度比较,探讨适合牙科氧化物陶瓷的粘接材料.方法: 分别用3 种树脂水门汀Superbond C&B、RelyX~(TM)Unicem、Panavia~(TM) F与喷砂后的氧化锆(ZrO2)及三氧化二铝(Al_2O_3)陶瓷的粘接面粘接,37 ℃水浴24 h后测试其粘接抗剪强度,数据用SAS 9.12 软件进行统计学分析.结果: Al_2O_3陶瓷组间均有显著性差异(P<0.000 1), Superbond C&B粘接强度最高为(37.60±2.06) MPa. ZrO2陶瓷组中Superbond C&B与Panavia~(TM) F的粘接强度差异无显著性(P>0.05),RelyX~(TM)Unicem粘接强度最低为(13.29±3.05) MPa.结论: Superbond C&B、Panavia~(TM) F与氧化物陶瓷均具有较高的粘接强度,一步法自酸蚀粘接剂RelyX~(TM)Unicem虽然操作简便、提高了工作效率,但不如多步法系统获得的粘接强度大.