酸蚀时间对牙釉质粘接剂剪切强度影响的研究

目的:研究不同酸蚀时间和不同施力方向对正畸托槽与牙面间剪切强度的影响.方法:选择180个正畸减数的前磨牙,根据酸蚀时间(15 s、30 s、45 s、60 s)的不同,随机分为四组,每组45个牙分别进行4次实验,将45个牙按不同施力方向(0°、45°、90°)分为3个亚组,每组15个牙.用WDW3050型电子万能试验机,YD-88型电阻应变仪测量正畸托槽剪切强度,并评价牙釉质粘接剂残留指数(ARI).结果:酸蚀30 s的剪切强度比酸蚀15 s的剪切强度大,有显著性差异.酸蚀45 s和60 s与酸蚀30 s 的剪切强度没有显著性差异;酸蚀时间越长,粘接剂残留指数(ARI)越大;施力角度不同,ARI不同,水平方向ARI最小,45°次之,90°最大.结论:酸蚀30 s可达到临床正畸矫治需要的粘接强度,且粘接剂残留指数相对较小,易于去除托槽而不损伤牙釉质.     

酸蚀时间对乳牙釉质脱矿的影响

目的:采用激光共聚焦显微镜观察不同酸蚀时间对乳牙釉质脱矿的影响,对不同酸蚀时间形成的乳牙釉质的脱矿区进行形态学和数据学评价。方法:采用随机区组设计,将28颗离体下中切牙的唇面分别开4个窗,随机分到酸蚀30s(A)、60s(B)、90s(C)、120s(D)4个处理组中,采用32%磷酸凝胶对标本进行酸蚀处理。0.1mmol/L罗丹明B染色后,进行激光共聚焦显微镜扫描。采用SPSS11.0软件包对数据进行正态性检验和S-N-K法检验。结果:随着酸蚀时间的延长,釉质脱矿条带有所增粗,鱼鳞状结构变得不明显。衡量釉质脱矿程度的3个参数,荧光面积(FLA)、总荧光量(TF)和平均荧光量(AF)的均值随着酸蚀时间的延长而有所增大。A、B、C、D4组的FLA均值分别为(5.5±1.6)×102μm2、(7.4±2.7)×102μm2、(9.2±3.0)×102μm2和(9.6±2.9)×102μm2;4组的TF均值分别为(3.5±1.3)×104、(5.7±2.9)×104、(8.3±3.6)×104和(9.7±3.4)×104;AF均值分别为128.4±35.3、166.6±21.1、200.8±19.4和219.1±12...     

氟化钠抗碳酸饮料酸蚀乳牙釉质作用的研究

目的：探讨氟化钠抗碳酸饮料对乳牙釉质酸蚀的效果。方法：用人下颌乳切牙制备72个釉质块,将其随机平均分为3组：对照组釉质块不作涂氟处理,实验组两组釉质块分别涂0.6%和1.23%浓度氟化钠;各组再按浸泡在碳酸饮料中的时间不同分成30 min和50 min两个亚组。将各组釉质块分别浸泡于碳酸饮料中30 min或50 min,取出后用去离子水冲洗,将实验组重新涂氟,然后再将釉质块浸泡在碳酸饮料中,如此循环直至12 h。用扫描电镜观察乳牙釉质表面形态改变,显微硬度计测定釉质表面硬度值（surface micro-hardness,SMH）变化,评估氟化钠保护乳牙釉质抗碳酸饮料酸蚀的效果。结果：与对照组比较,经两种浓度氟化钠处理过的乳牙釉质能不同程度地抵抗碳酸饮料的酸蚀作用,SMH值较高（P〈0.05）;随着碳酸饮料浸泡时间的延长,氟化钠保护乳牙釉质抗酸蚀的能力下降;较高浓度的氟化钠的保护效果更好,差异有统计学意义（P〈0.05）。结论：氟化钠能够增强乳牙釉质抗碳酸饮料酸蚀能力。     

酸蚀剂型和酸蚀时间对窝沟封闭剂——釉质粘结强度的影响

简化涂布工艺，减少操作时间是窝沟封闭剂(以下简称封闭剂)临床应用中需解决的重要问题，有学者比较了液型、相型、胶型粘结效果，以胶型最佳，也有报告液型和胶型两种剂型酸蚀荆的涂膜保留率相似，有人发现釉树脂—向质粘结强度，发现只需酸蚀5s就可达到常规60s的粘结强度，本研究观察酸蚀剂型和酸蚀时闻对封闭剂—釉质粘结强度的影响，为临床应用提供参考。     

不同釉质酸蚀技术对正畸托槽粘接的影响

牙面的酸蚀是影响正畸粘接力的一个重要因素，如何正确选择和使用酸蚀方法一直是研究的热点。本文就酸蚀剂的不同种类、剂型、浓度、酸蚀时间及酸蚀技术对正畸粘接力的影响作一综述。     

不同酸蚀条件对釉质表面的影响研究

目的　探究不同pH值的盐酸溶液和酸蚀时间对釉质表面的影响。方法　制作40个釉质片样本，每个样本表面分为未处理面和处理面。根据处理面酸蚀条件分为8组，其中酸蚀时间为30 s，pH值分别为1.6、2.4、3.2、4.0的4组记为A1、A2、A3、A4组；酸蚀时间为60 s，pH值分别为1.6、2.4、3.2、4.0的4组记为B1、B2、B3、B4组。利用显微硬度计测量样本表面显微硬度；激光共聚焦显微镜测量样本未处理面和处理面之间形成的高度差（即釉质丧失量）。对结果进行两因素析因设计资料的方差分析。结果　酸蚀后，A1～A4组样本表面显微硬度值分别下降（42.1 ± 5.8）、（23.6 ± 5.7）、（10.9 ± 6.9）和（-0.6 ± 2.6）MPa；B1～B4组样本表面显微硬度值分别下降（59.3 ± 6.6）、（35.4 ± 9.2）、（15.7 ± 5.1）和（7.7 ± 3.1）MPa。A1～A4组样本未处理面和处理面之间的高度差分别为（793.4 ± 43.0）、（319.2 ± 20.4）、（15.8 ± 2.4）和（-1.4 ± 3.3）nm；B1～B4组样本未处理面和处理面之间的高度差分别为（1366.6 ± 174.8）、（437.2 ± 41.0）、（75.1 ± 6.4）和（1.3 ± 3.2）nm。方差分析结果显示，酸蚀时间和盐酸溶液的pH值对釉质表面显微硬度值下降量及釉质丧失量均有显著影响。结论　酸蚀时间和盐酸溶液的pH值均是影响釉质表面显微硬度值下降量及釉质丧失量的因素，且酸蚀时间和盐酸溶液的pH值对釉质丧失量的影响存在交互作用。     

不同釉质酸蚀技术对正畸托槽粘接的影响

牙面的酸蚀是影响正畸粘接力的一个重要因素,如何正确选择和使用酸蚀方法一直是研究的热点。本文就酸蚀剂的不同种类、剂型、浓度、酸蚀时间及酸蚀技术对正畸粘接力的影响作一综述。     

酸蚀时间对临床托槽脱落率的影响

目的：比较15秒和60秒酸蚀后临床托槽脱落率的差异，从而探讨正畸临床适宜的牙釉质酸处理时间。方法：选择年龄为11—16岁的正畸患者30名，随机分为两组，两组患者按不同牙位分别进行两种时间的酸蚀。酸蚀后常规粘结方丝托槽，每次复诊时分别记录两组托槽脱落数，连续记录三个月。结果：15秒酸蚀组总脱落率为7．777％，60秒酸蚀组总脱落率为3．333％，前牙托槽脱落数明显少于后牙，最易脱落的托槽为第二前磨牙。结论：建议正畸临床上粘结前牙可使用15秒的酸蚀时间。第二前磨牙及腭向错位侧切牙宜适当延长酸蚀时间。     

三种氟化物增强乳牙釉质抵抗饮料酸蚀和再矿化作用的研究

目的观察三种氟化物处理后的乳牙釉质表面抵抗软饮料酸蚀及促进受损牙釉质再矿化的能力。方法应用显微硬度仪和扫描电镜,观测分别用NaF溶液、氟保护剂、双氟脱敏剂处理后再经饮料浸泡的乳牙釉质表面的显微硬度值(surfacemicrohardness,SMH)及形态的变化。结果饮料浸泡后,各组乳牙釉质的SMH均有明显降低;氟化物处理组的釉质SMH降低的程度明显低于对照组(P<0.001);氟保护剂和双氟脱敏剂组釉质SMH的降低无显著性差异,而低于单纯的NaF溶液组;扫描电镜可见釉质表面有不同程度的溶解。饮料侵蚀后又经氟化物再矿化的乳牙,釉质SMH明显增加,其中双氟脱敏剂组的釉质SMH增加最明显。结论釉质表面应用氟化物,能明显增强乳牙釉质抵抗软饮料酸蚀,并能促进受损牙釉质的再矿化修复能力,其中双氟脱敏剂的作用最明显。     

酸蚀时间对乳牙釉质表面结构及树脂抗剪粘接强度的影响

目的:研究酸蚀时间对乳牙釉质表面形态、树脂-釉质粘接强度及界面结构的影响,确定乳牙的最佳酸蚀时间.方法:选取12颗乳牙,随机分为4组,按照15、30、60、120 s时间,采用GLUMA Etch 20 GEL酸蚀乳牙唇而釉质,扫描电镜观察其表而结构;另选取48颗乳牙,将内径4 mm,高2 mm的铜圈用蜡固定在乳牙唇面,按分组方法进行酸蚀.吹干;按照Gluma粘接系统及树脂操作方法.形成柱状光固化复合树脂修复体,其中40个试样用万能测试机测试其抗剪粘接强度;剩余8个试样采用金刚砂片垂直于树脂牙釉质结合面切开,扫描电镜观察其界而结构.结果:乳牙酸蚀30 s和60 s时釉质表面呈均匀的鱼鳞状结构,酸蚀15 s 时釉质表面只有极少部分鱼鳞状,而120 s时釉质鱼鳞状结构消失.牙本质小管暴露;酸蚀15、30、60、120 s组的树脂-釉质粘接强度分别为5.34、10.59、12.22、3.73 MPa;扣描电镜显示树脂-釉质界面结构30 S组和60 S组有长树脂突形成,而15 s组和120 s组界面几乎旱平面,无长树脂突形成.结论:乳牙酸蚀的最佳时间足30～60 s间.     

Enamel roughness and depth profile after phosphoric acid etching of healthy and fluorotic enamel

Background: Dental fluorosis requires aesthetic treatment to improve appearance and etching of enamel surfaces with phosphoric acid is a key step for adhesive restorations. The aim of this study was to evaluate surface roughness and a depth profile in healthy and fluorotic enamel before and after phosphoric acid etching at 15, 30 and 60 seconds. Methods: One hundred and sixty enamel samples from third molars with no fluorosis to severe fluorosis were evaluated by atomic force microscopy. Results: Healthy enamel showed a statistically significant difference (p < 0.05) between mean surface roughness at 15 seconds (180.3 nm), 30 seconds (260.9 nm) and 60 seconds (346.5 nm); depth profiles revealed a significant difference for the 60 second treatment (4240.2 nm). For mild fluorosis, there was a statistically significant difference (p < 0.05) between mean surface roughness for 30 second (307.8 nm) and 60 second (346.6 nm) treatments; differences in depth profiles were statistically significant at 15 seconds (2546.7 nm), 30 seconds (3884.2 nm) and 60 seconds (3612.1 nm). For moderate fluorosis, a statistically significant difference (p < 0.05) was observed for surface roughness for 30 second (324.5 nm) and 60 second (396.6 nm) treatments. Conclusions: Surface roughness and depth profile analyses revealed that the best etching results were obtained at 15 seconds for the no fluorosis and mild fluorosis groups, and at 30 seconds for the moderate fluorosis group. Increasing the etching time for severe fluorosis decreased surface roughness and the depth profile, which suggests less micromechanical enamel retention for adhesive bonding applications.     

正畸多次酸处理后牙釉质表面的扫描电镜观察

目的：通过扫描电镜观察正畸多次酸处理后牙釉质表面的结构变化。方法：以正畸临床即将拔除的正常第一双尖牙为实验样本,分为实验组和对照组。应用５０％ 的磷酸处理牙齿的颊面,时间为６０ｓ。对实验组样本分１、２、３ 次粘结托槽。按所设计的酸处理与粘结托槽的次数拔除该牙并固定,扫描电镜下进行观察。结果：镜下的观察显示,第一次酸处理后只是部分釉柱的轻度脱钙,蜂窝样结构少而不均匀。第二次酸处理后牙釉质表面蜂窝样结构密集而规则。经一、二次粘结后牙釉质表面残留的树脂均比较少,第三次粘结后牙釉质表面相对有较多的树脂残留。结论：第二、三次粘结托槽,仍会获得较好的机械性粘合。     

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目的探讨正畸临床牙釉质的最佳酸处理时间。方法从2005年大连市口腔医院外科门诊200颗正畸减数拔除的双尖牙中挑选出13颗作为样本,随机抽取其中3颗作为对照,未作酸处理。10颗进行酸处理的实验牙用约1mm宽的蜡条沿牙冠颊轴嵴作分界线,蜡条覆盖部分作为对照区。扫描电镜下观察未酸蚀的对照牙、实验牙对照区和经过15s和60s酸蚀处理后的实验牙釉质表面形态。结果镜下观察结果显示:酸蚀前釉质表面多较为光滑,似云片、积雪状外观;酸蚀后在小部分样本釉质表面中看到典型的蜂窝样和鹅卵石样形态。构成比显示60s酸蚀组较15s酸蚀组釉质丢失量多。结论60s酸蚀组较15s酸蚀组釉质丢失更严重,为了尽可能地减少酸蚀粘接对牙釉质的损害,正畸临床可将酸蚀时间适当减少。     

Effect of lingual enamel sandblasting with aluminum oxide of different particle sizes in combination with phosphoric acid etching on indirect bonding of lingual brackets

Objective:To compare bond strength and bond failure location of lingual brackets indirectly bonded after lingual enamel sandblasting with 27-, 50-, and 90-µm aluminum oxide particles followed by 37% phosphoric acid etching.Material and Methods:Eighty maxillary premolars were randomly divided into four equal groups according to the method of lingual enamel surface conditioning: Group 1 (control) was etched with 37% phosphoric acid, and group 2, group 3, and group 4 were sandblasted with 27-, 50-, and 90-µm aluminum oxide particles, respectively, prior to acid etching. Lingual brackets were indirectly bonded using the same protocol and adhesive (Sondhi) in all groups. The maximum shear bond strength required to debond the brackets was measured using a testing machine, and the bond failure location was classified according to the adhesive remnant index (ARI). Analysis of variance was used to compare the mean bond strength between groups. The differences between ARI scores were evaluated using the Kruskal-Wallis test.Results:There were no statistically significant differences in mean shear bond strength or ARI scores between the four enamel-conditioning procedures.Conclusion:Lingual enamel sandblasting using different particle sizes of aluminum oxide prior to phosphoric acid etching did not increase the shear bond strength of indirectly bonded brackets and did not affect the amount of adhesive remnant on the enamel.     

Effects of phosphoric acid on bovine enamel bleached with carbamide peroxide

The aim of this study was to measure the demineralization capacity of 37% phosphoric acid on bovine enamel at different time-points after bleaching with 30% carbamide peroxide. Five, 4 × 4-mm sections were obtained from the enamel of 10 bovine incisors. After applying 30% carbamide peroxide (Vivastyle) for 90 min, specimens were stored in artificial saliva for 0, 24, 72 h, or 7 d and then immersed in 37% phosphoric solution. At 15, 30, 60, 90, and 120 s, 5-ml aliquots were extracted. A control group of specimens was not bleached. Ca²⁺ concentrations were measured by atomic absorption spectrophotometry. A larger amount of Ca²⁺ was extracted from enamel by phosphoric acid after the application of 30% carbamide peroxide. Twenty-four hours after bleaching, significantly more Ca²⁺ was extracted from bleached than from control specimens at all time-points, and this greater susceptibility to the action of the acid persisted for at least 1 wk after bleaching.     

不同溶剂的酒石酸酸蚀对黏结强度影响的研究

目的观察用不同溶剂的酒石酸酸蚀牙釉质表面对黏结强度的影响。方法40颗前磨牙随机分为4组,分别用10%的酒石酸水溶液、10%酒石酸乙醇水溶液、10%酒石酸丙酮水溶液及37%磷酸酸蚀(对照组)前磨牙颊面牙釉质表面后,用京津釉质黏合剂黏结舌侧扣。通过电子万能实验机测量记录舌侧扣在轴向拉力作用下脱位的张力强度。结果用37%磷酸酸蚀、10%的酒石酸水溶液酸蚀、10%酒石酸乙醇水溶液酸蚀、10%酒石酸丙酮水溶液酸蚀牙釉质后,京津釉质黏合剂黏结舌侧扣脱位的张力强度分别为(4.12±1.11)MPa、(4.42±1.64)MPa、(2.57±0.75)MPa、(2.65±1.22)MPa,4者间有显著性差异(P<0.01)。结论不同溶剂的酒石酸酸蚀对黏结强度有一定的影响。     

釉质酸蚀后牙面脱矿与再矿化的扫描电镜观察

目的:观察牙釉质酸蚀后在离体状态下和一段时间内在口腔环境中的结构变化,探讨牙釉质脱矿与再矿化的形态学改变.方法:选择因正畸需要拔除健康第一前磨牙病例10例,40个牙,使用YY0269-1995型酸蚀剂对拟拔除的第一前磨牙颊侧釉质酸蚀60 8,左侧上、下颌第一前磨牙为A组,A组再分为A1、A2组,A1组酸蚀后即刻拔除,制作扫描电镜观察标本,A2组,第一前磨牙酸蚀后即刻拔除,置37℃恒温蒸馏水中浸泡1个月后制作电镜标本观察.右侧上、下颌第一前磨牙为B组,第一前磨牙酸蚀后在口内存留1个月后拔除,用相同的方法进行观察,并比较A、B两组牙釉质形态学变化.结果:A组的牙釉质表面松软,不规则,多孔隙,表面呈蜂窝状改变;B组的牙釉质表面有大量矿物质沉积,孔隙变小,矿化物颗粒细小,沉积不均匀.结论:牙釉质脱矿后,在口腔环境中可发生再矿化,但矿化程度是有限的,提示在临床上应注意酸蚀时间及酸蚀范围.     

Influence of phosphoric acid etching on microleakage of a self-etch adhesive and a self-adhering composite

Background: The aim of this study was to evaluate the influence of preliminary phosphoric acid etching on the microleakage of a self‐adhering flowable composite and a self‐etch adhesive used in combination with the proprietary flowable composite. Methods: Standard Class V cavities were prepared on the buccal side of 20 extracted sound human molars. Specimens were randomly divided into five groups: (1) Gel Etchant/Optibond FL/Premise Flowable; (2) Vertise Flow; (3) Optibond XTR/Premise Flowable; (4) Gel Etchant/Vertise Flow; and (5) Gel Etchant/Optibond XTR/Premise Flowable (Kerr). The interfacial sealing ability of the materials was evaluated by scoring the depth of silver nitrate penetration and through scanning electron microscopy observations. Differences in leakage at either the enamel or the dentine interface were evaluated for statistical significance (Kruskal–Wallis ANOVA, Mann–Whitney U test, p < 0.05). Results: At the enamel interface, no significant differences were found among the materials. On dentine, Gel Etchant/Vertise Flow had the highest leakage scores and the difference was statistically significant (p < 0.05). Conclusions: The early sealing ability of the self‐adhering flowable composite and the self‐etch adhesive in Class V restorations did not significantly benefit from selective enamel etching. Preliminary phosphoric acid etching of dentine negatively affected the quality of the seal when using the adhesive‐free flowable composite.     

酸蚀后牙面不同处理方法对托槽粘接效果的影响

目的探讨三种临床常见的不同的酸蚀后牙面处理方法对托槽粘接效果的影响。方法对３０例气水枪冲洗,湿棉球擦拭及酒精棉球擦拭等三种不同酸蚀后牙面处理方法的临床托槽脱落率及粘接剂残留指数ＡＲＩ进行回顾性统计比较。结果气水枪冲洗酸蚀牙面组托槽脱落率最低,ＡＲＩ计分最高;湿棉球擦拭酸蚀牙面组及以酒精棉球擦拭酸蚀牙面组托槽脱落率较高,ＡＲＩ计分较低,后二者与前者相比,托槽脱落率存在着显著差异。结论该结果提示,以气水枪冲洗酸蚀牙面是防止托槽脱落的一个重要方法