计算机辅助正畸托槽间接粘接技术的研究

目的研究计算机辅助下的正畸托槽间接粘接技术的可行性。方法采用激光扫描仪获取石膏牙颌模型的数字化信息,利用工程软件绘制真实大小的直丝弓托槽,在虚拟模型上实现托槽的定位,通过计算机辅助设计出用于托槽定位的个体托盘,并利用快速成型技术进行加工。结果通过计算机辅助设计及快速成型技术可以实现正畸托槽的间接粘接。结论计算机辅助正畸托槽的间接粘接,能够保证托槽的精确位置,同时节约椅旁占用时间,减少实验室操作步骤,可作为托槽间接粘接的新技术。     

正畸托槽间接粘接的临床应用

目的 探讨正畸托槽的间接粘接技术,以提高托槽定位的准确性。方法 选取南京医科大学附属口腔医院正畸科18名成人正畸患者,采用间接粘接技术粘接托槽,模型粘接和口内粘接均为同一医生进行,技工室压模均由同一技工完成。结果 18例患者的302个托槽在粘接过程中,有13个托槽在压模时发生脱落,1个在口内粘接时脱落。与直接粘接法相比,间接粘接法椅旁操作时间减少,但操作繁琐、总操作时间增加。结论 间接粘接技术托槽放置精确,椅旁操作时间减少,利于初学者培养托槽定位感,适合舌侧矫治器的粘接。     

氟化物在预防正畸釉质脱矿中的应用

釉质脱矿是正畸临床中经常伴有的牙体损害,一旦发生,大部分不可逆转,常会影响到牙齿的健康和美观,因此预防釉质脱矿非常重要.氟化物的应用可以抑制釉质脱矿的发生并促进釉质再矿化.氟化物防龋机制主要是降低釉质溶解度、生成氟化钙和氟磷灰石来促进釉质再矿化.本文就氟化物预防正畸釉质脱矿的可能机制和预防方法进行综述.     

Resin bonding using an all-etch or self-etch adhesive to enamel after carbamide peroxide and/or CPP-ACP treatment

BACKGROUND: Limited evidence exists regarding the effect of carbamide peroxide and casein phosphopeptide amorphous calcium phosphate (CPP-ACP) on composite-enamel bonding. Microshear bond strengths, using either a total-etch or self-etching adhesive, to enamel treated with carbamide peroxide and/or CPP-ACP were investigated. MATERIALS AND METHODS: Twenty-six extracted human third molars were sectioned into four parts, each being allocated into one of the four groups (n=26): bleach (Polanight, 16% carbamide peroxide), CPP-ACP (GC Tooth Mousse), bleach and then CPP-ACP, or untreated (control). The surfaces were bonded with a total-etch bonding system (Single Bond) or a self-etching primer system (Clearfil SE Bond) and tested using a microshear test. RESULTS: A significant difference in bond strength was found between bonding systems. SE Bond showed the highest bond strength to untreated enamel (p < 0.05). The microshear bond strength of SE Bond decreased when the enamel was treated with carbamide peroxide, CPP-ACP or both (p < 0.05). Only combined use of carbamide peroxide and CPP-ACP significantly affected microshear bond strength with Single Bond. CONCLUSION: These findings suggest the shear bond strength of resin to enamel using a self-etching priming adhesive may be affected if the enamel is treated with a bleaching agent or CPP-ACP.     

纳米二氧化钛对正畸粘接剂抗菌性与拉伸粘接强度的影响

目的研究纳米级二氧化钛对正畸托槽粘接剂抗菌效果及拉伸粘接强度的影响。方法在光固化托槽粘接剂(Grengloo)中加入质量分数1%、2%、3%纳米级二氧化钛。空白对照组不加入二氧化钛。将托槽粘接于离体前磨牙上,测量拉伸粘接强度与粘接剂残留量。粘接剂制成树脂圆片与菌悬液共培养48 h后,进行细菌活性与代谢测定。结果 4组粘接剂的拉伸粘接强度和粘接剂残留指数无显著差异。2%、3%组的pH值明显增加、乳酸产生量明显减少,但两组间无明显差别。加入纳米二氧化钛的三组菌落计数均明显减少,但3组间无明显差别。结论 2%纳米二氧化钛对Grengloo托槽粘接剂拉伸粘接强度无明显影响,同时提高其抗菌性。     

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目的探讨影响直接法黏结托槽脱落的临床因素。方法选择2005—2010年江苏省苏北人民医院口腔科门诊收治的正畸固定矫治患者93例(1580个托槽),采用直接法黏结托槽,矫治后3～4周复诊并对脱落托槽的患者年龄、牙位、上下颌位置及操作者进行统计分析。结果在矫治过程中共有241个托槽脱落,占总数的15.2%。<18岁患者托槽脱落率明显高于≥18岁患者(P<0.05);双尖牙托槽脱落率明显高于前牙(P<0.05);下颌托槽脱落率明显高于上颌(P<0.05);不同操作者间托槽脱落率差异有统计学意义(P<0.05)。结论患者年龄、牙位、上下颌位置及操作者的临床经验均直接影响正畸托槽的黏结效果。     

Enamel bonding of self-etch and phosphoric acid-etch orthodontic adhesive systems

This study was conducted to examine the shear bond strengths of orthodontic brackets to ground enamel with two self-etching adhesives (Beauty Ortho Bond and Transbond XT) and two phosphoric acid-etching adhesives (Kurasper F and Orthomite Superbond). After the bonded specimens were stored in water at 37 degreees C for 24 hours, they were subjected to thermal cycling (TC) at 0 and 5000 cycles. Then, shear bond test was performed at a crosshead speed of 1 mm/min. Results indicated that the self-etching adhesives did not significantly differ in bond strength before and after TC (p>0.05), while the phosphoric acid-etching adhesives showed a significant reduction after TC (p<0.05). The predominant modes of bracket failure for the self-etching adhesives were at the enamel-resin interface, leaving less than 50% of the adhesive on the enamel surface. It was concluded that the self-etching adhesives exhibited stable bond strength to ground enamel without causing decalcification nor damage to the enamel surface.     

Shear bond strength of orthodontic brackets with newly developed antibacterial self-etch adhesive

Because the enamel adjacent to brackets may be affected by microorganisms, an antibacterial adhesive may be a useful choice to prevent and reduce demineralization. The purpose of this in vitro study was to determine the (1) shear bond strength of a self-etch and an antibacterial self-etch adhesive for orthodontic metal brackets and (2) bond failure interface of a self-etch and an antibacterial self-etch adhesive using a modified adhesive remnant index (ARI). Twenty-four defect-free premolars were randomly assigned into two groups. The teeth received the following treatments-group 1: Transbond Plus Self-Etching Primer + Transbond XT; group 2: antibacterial dentin bonding system (ABF) + Transbond XT. All samples were stored in deionized water at 37 degrees C for 48 hours. Shear debonding tests were performed at a crosshead speed of five mm/min. The results in megapascals were (median, minimum, maximum) group 1: 8.53, 4.59, 12.63; group 2: 9.79, 4.01, 22.10, respectively. Mann-Whitney test revealed that the difference between the groups was not statistically significant (P = .2, P > .05). Failed brackets were examined by an optical microscope at 16x magnification to determine the bond failure interface using a modified ARI. The predominant mode of failure for both groups was at the bracket-adhesive interface. ABF may have sufficient mechanical properties and also an antibacterial effect that makes it a good choice for orthodontic bonding.     

Effect of pine bark extract on bond strength of brackets bonded to bleached human tooth enamel

Abstract

Aim. The purpose was to investigate the effect of pine bark (proanthocyanidin, natural antioxidant) solution on the shear bond strength (SBS) of metal brackets bonded with composite resin to human enamel after bleaching with hydrogen peroxide (HP). Materials and methods. Sixty recently extracted premolars were divided into an experimental group (n = 45), which was bleached with 40% HP, and a control group (n = 15), which was not bleached. The experimental group was further divided into three sub-groups. Specimens in group IB (n = 15) were bonded immediately after bleaching; specimens in group SA (n = 15) were bleached, then treated with 10% sodium ascorbate and then bonded; group PB specimens (n = 15) were bleached, then treated with 5% pine bark solution and bonded. The specimens were debonded with Universal testing machine. The adhesive remnant index was calculated. Results. No significant differences in shear bond strength were noted when the pine bark treated group was compared with the control group and sodium ascorbate group (p > 0.05). Treating the bleached enamel surface with 10% sodium ascorbate or 5% pine bark solution reverses the SBS reduction. Conclusion. So, as a natural antioxidant and less hazardous, clinicians can choose pine bark solution instead of sodium ascorbate.     

Clinical evaluation of two materials for the bonding of composite resins to dentine: one-year results

Non-undercut Class V abrasion cavities were restored using either Creation Bond dentine bonding agent and Visar-Fil composite resin (42 cavities), or Dentin Adhesit dentine bonding agent with Silux composite (42 cavities) or Heliosit composite (31 cavities). No enamel etching was carried out. The restorations were examined after approximately one month, three months, six months and one year.
The results showed a cumulative loss rate of Creative Bond/Visar-Fil restorations of 55 per cent after one month, increasing to 96 per cent after one year. Comparative results were 52 per cent to 93 per cent for Adhesit/Silux restorations, and 23 per cent to 77 per cent for Adhesit/Heliosit restorations. Remaining restorations of all materials had varying degrees of marginal staining.     

不同再粘接方法对托槽粘接效果的影响

目的评价托槽再粘接过程中酸蚀对再粘接效果的影响,比较传统两步法和自酸蚀一步法对再粘接效果的影响。方法收集40颗由于正畸治疗需要拔除的上颌第二前磨牙,随机分成4组。分别运用传统两步法(组1和组2)和自酸蚀一步法(组3和组4)进行首次托槽粘接。然后再去托槽,进行牙面处理,各组分别用相同的粘接剂重新粘接,其中组2和组4粘接前无酸蚀。再粘接后24h,对40颗牙进行剪切粘接强度(SBS)以及粘接剂剩余指数(ARI)的检测,并在扫描电镜下对牙釉质面进行观察。结果按组1-组4的顺序,其平均SBS值分别为14.18、6.57、11.90和5.91 MPa。其中组1与组2、组3与组4之间的差异有统计学意义(P<0.05);而组1与组3、组2与组4之间无统计学差异(P>0.05)。ARI指数在组1与组2之间差异具有统计学意义(P<0.05);其它各组间无统计学差异(P>0.05)。扫描电镜照片显示:组1与组2的釉质面上有大面积以及较深的沟裂;组3与组4釉质上有相对较浅的小凹。结论在本试验条件下:①再粘接过程中未经酸蚀也可获得临床所需的粘接强度,且牙釉质面比再次酸蚀者破坏范围相对较小;②传统两步法与自酸蚀一步法所获的托槽再粘接强度以及粘接剂剩余指数无明显差异。     

自锁托槽矫治技术的临床研究进展

自锁托槽自问世以来不断改进发展,代表了直丝弓矫治器的发展方向.自锁托槽通过闭锁结构替代了传统托槽橡皮圈或结扎丝对弓丝的结扎,根据其对弓丝的加力方式主要分为主动自锁托槽与被动自锁托槽.因自锁托槽无需结扎,临床操作方便、快捷,节省椅旁工作时间,摩擦力低,在正畸临床应用中日趋广泛,本文就自锁托槽临床应用中矫治力的选择、矫治时...     

两种氟保护漆用于预防正畸治疗釉质脱矿的临床比较研究

目的：比较两种氟保护漆预防正畸治疗釉质脱矿的临床效果。方法：选取临床正畸患者20例440颗需要粘接正畸装置的牙齿,采用自身对照的方法,实验组220颗牙,用氟保护漆ClinproTM XT Varnish（3M ESPE）处理牙面,对照组220颗牙,用氟保护漆Fluor Protector（Vivadent）处理牙面。观察两组牙齿托槽脱落率及釉质脱矿指数（enamel decalcification index,EDI）。结果：实验组和对照组的托槽脱落率经统计学分析,差异无统计学意义（x2＝0．259,P ＝0．611）;两组釉质脱矿指数比较,差异无统计学意义（t＝0．362,P＝0．718）。结论：氟保护漆ClinproTM XT Varnish和Fluor Protector用于预防正畸治疗中釉质脱矿具有较好的临床效果。     

In vivo bonding of orthodontic brackets to fluorosed enamel using an adhesion promotor

OBJECTIVES: To determine the success of bracket retention using an adhesion promoter with and without the additional microabrasion of enamel. MATERIALS AND METHODS: Fifty-two teeth with severe dental fluorosis were bonded in vivo using a split-mouth design where the enamel surfaces of 26 teeth were microabraded with 50 microm of aluminum silicate for 5 seconds under rubber dam and high volume suction. Thirty-seven percent phosphoric acid was then applied to the enamel, washed and dried, and followed by placement of Scotchbond Multipurpose Plus Bonding Adhesive. Finally, precoated 3M Unitek Victory brackets were placed and light cured. The remaining teeth were bonded using the same protocol but without microabrasion. RESULTS: After 9 months of intraoral service, only one bond failure occurred in the control group where microabrasion was used. Chi-square analysis revealed P = .31, indicating no statistical significance between the two groups. CONCLUSIONS: Bonding orthodontic attachments to fluorosed enamel using an adhesion promoter is a viable clinical procedure that does not require the additional micro-mechanical abrasion step.     

Clinical bond failure of pre-coated and operator-coated orthodontic brackets

Objectives – To test the hypothesis that there is no significant difference in clinical bracket failure between the 3M APC Mini Twin? bracket system and the Transbond XT? adhesive during orthodontic treatment. Design – A randomized, split mouth, prospective clinical trial. Setting and Sample Population – The Department of Orthodontics and Dentofacial Orthopedics at University of Missouri, Kansas City. Twenty‐nine subjects who were treatment planned to receive comprehensive orthodontics using 0.018 slot appliances. Experimental Variable – The adhesive pre‐coated brackets (APC ) system was randomly assigned to one side of the mouth and the Transbond XT^TMwas assigned to the opposite side. Outcome Measure – The absence of any of the brackets at the time of a regular or emergency orthodontic appointment. Results – There was no significant difference (P > 0.05) in bracket failure between the 3M APC Mini Twin^TM bracket system and the Transbond XT^TM adhesive at any time period (90, 180, or 365 days). The failure rate of brackets on premolars was higher than on incisors or canines. Conclusion – APC Mini Twin^TM bracket system and Transbond XT^TMadhesive are equally effective in maintaining brackets clinically. Inexperienced operators had an overall 7.5% bond failure 12 months following bracket placement.     

Effect of a self-etch primer/adhesive on the shear bond strength of orthodontic brackets

Conventional adhesive systems use 3 different agents (an enamel conditioner, a primer solution, and an adhesive resin) during the bonding of orthodontic brackets to enamel. A unique characteristic of some new bonding systems in operative dentistry is that they combine the conditioning and priming agents into a single product. Combining conditioning and priming saves time and should be more cost-effective to the clinician and, indirectly, to the patient. The purpose of this study was to determine the effects of the use of a self-etch primer on the shear bond strength of orthodontic brackets and on the bracket/adhesive failure mode. Brackets were bonded to extracted human teeth according to 1 of 2 protocols. In the control group, teeth were etched with 37% phosphoric acid. After the sealant was applied, the brackets were bonded with Transbond XT (3M Unitek, Monrovia, Calif) and light cured for 20 seconds. In the experimental group, a self-etch acidic primer (ESPE Dental AG, Seefeld, Germany) was placed on the enamel for 15 seconds and gently evaporated with air, as suggested by the manufacturer. The brackets were then bonded with Transbond XT as in the first group. The present in vitro findings indicate that the use of a self-etch primer to bond orthodontic brackets to the enamel surface resulted in a significantly (P = .004) lower, but clinically acceptable, shear bond force (mean, 7.1 +/- 4.4 MPa) as compared with the control group (mean, 10.4 +/- 2.8 MPa). The comparison of the adhesive remnant index scores indicated that there was significantly (P = .006) more residual adhesive remaining on the teeth that were treated with the new self-etch primer than on those teeth that were bonded with the use of the conventional adhesive system.     

粘贴含氟正畸托槽后菌斑和唾液中氟离子的变化

目的 测定粘贴含氟正畸托槽后,口腔内菌斑及唾液氟离子浓度的变化,探讨采用含氟正畸托槽预防牙釉质脱矿的意义.方法 选择10名志愿者,口腔内粘贴含氟正畸托槽.用离子选择性氟电极测定口腔内菌斑及唾液氟离子浓度,并与粘贴托槽前的基线水平相比较.结果 粘贴含氟正畸托槽后,菌斑及唾液中氟浓度均升高,唾液氟浓度持续3天高于基线水平,...