不同自锁托槽摩擦力的实验研究

目的：探讨干燥条件下,被动自锁托槽系统与主动自锁托槽系统分别和不同弓丝组合时,在后牙段所产生的摩擦力差异.方法：在干燥条件下,分别测试2种被动自锁托槽系统（Damon 3,3M Smart clip）、2种主动自锁托槽系统（Tomy,Time 2）与3种弓丝（0.019×0.025英寸NiTi方丝、0.019×0.025英寸SS方丝、0.014英寸NiTi圆丝）组合在后牙段的动、静摩擦力.结果：0.019×0.025英寸NiTi方丝组中,被动自锁托槽与主动自锁托槽的摩擦力比较均有显著性差异,大小依次为Tomy＞Time2＞3M SmartClip＞Damon3自锁托槽的摩擦力;0.019×0.025英寸方丝组中,Tomy自锁托槽的摩擦力最大,然后依次为Time 2、3M SmartClip与Damon3自锁托槽（被动自锁托槽的摩擦力无显著性差异）;0.014英寸NiTi圆丝组中,4种自锁托槽的摩擦力无明显差异p＞0.05）.同一自锁托槽系统时,0.019×0.025英寸NiTi方丝的摩擦力最大,其次为0.019×0.025英寸SS方丝、0.014英寸NiTi圆丝.结论：在0.019×0.025英寸SS弓丝-自锁托槽组合中,被动自锁托槽系统产生的摩擦力＜主动自锁托槽系统（p＜0.05）：在0.014英寸SS弓丝-自锁托槽组合中,被动自锁托槽系统产生的摩擦力与主动自锁托槽系统的无明显差异（p＞0.05）.     

自锁托槽和传统直丝弓托槽弓丝结扎时间的对比研究

目的：比较Damon3、DamonMX、In-Ovation3种自锁托槽的弓丝自锁结扎与传统弹力结扎圈结扎、不锈钢丝结扎的椅旁操作时间。方法：5种结扎方式各选取10例不拔牙病例。上下牙列完全排齐整平、安放0．019×0．025”的不锈钢丝后，分别测量记录每位患者全口弓丝结扎以及去结扎所需要的时间，并进行统计学分析：结果：5种结扎方式的全口结扎时间分别为Damon 3：（13．4±0.4）s，Damon MX：（13．1±0.4）s，In—Ovation：（13．5±0.4）s，弹力结扎圈：（135．2±5．9）s，不锈钢丝：（644．6±22．8）s；全口去结扎时间分别为Damon3：（28．5±1．0）s，Damon MX：（27．5±1．1）s，In—Ovation：（28．9±0．8）s，弹力结扎圈：（42．2±2．5）s，不锈钢丝：（232．2±9．5）s。3种自锁托槽的全口结扎、去结扎时间均明显短于弹力结扎圈和不锈钢丝结扎，经统计学分析其差异具有统计学意义（P〈0．05）。结论：自锁托槽矫治器的弓丝自锁结扎与传统的弓丝结扎方式相比能明显地缩短弓丝结扎、去结扎所需的时间，从而减少椅旁操作时间，提高工作效率。     

自锁托槽的临床应用及研究进展

自锁托槽是一种新的托槽类型,可以通过托槽槽沟唇侧的滑盖或弹簧夹固定弓丝,简便了结扎过程,节省了椅旁操作时间,还有助于减小滑动阻力,减少关闭间隙的阻力,使矫治效力增加。自锁托槽与传统托槽一样,能三维方向控制牙的移动。大部分学者认为,使用自锁托槽矫治可以减少总治疗时间,延长复诊间隔时间,减少复诊次数,并且自锁托槽的脱落率和意外打开率和传统托槽无显著差异。     

自锁托槽和无托槽隐形矫治器对正畸患者牙周组织炎症状态的影响

目的 探讨自锁托槽和无托槽隐形矫治器对正畸患者牙周组织炎症状态的影响。方法 选取104例错畸形患者，根据患者自愿原则采用无托槽隐形矫治器和自锁托槽矫治器，各52例，评估两组粘戴托槽前及粘戴托槽24 h后的口腔咬合功能[去皮花生仁的咀嚼次数(MT)，并计算咀嚼效能(ME)、最大咬合力(MF)、最大合力时间(MFT)、咬合速率(SO)]，对比两组矫治前及矫治6个月后的牙周指数[牙龈指数(GI)、龈沟探诊深度(SPD)、龈沟出血指数(SBI)、菌斑指数(PLI)]、龈沟液中白细胞介素1β(IL-1β)、肿瘤坏死因子(TNF-α)水平和天门冬氨酸转氨酶(AST)及碱性磷酸酶(ALP)含量。结果 两组粘戴托槽24 h后的ME、MT、MF及SO值较粘戴托槽前有显著性降低(P<.05)，MFT值较粘戴托槽前有显著性升高(P<.05)，无托槽组矫治6个月后的GI、SPD、SBI及PLI值较矫治前无明显差异(P>0.05)，而自锁托槽组较矫治前有显著提高(P<.05)，无托槽组上述指标变化幅度显著小于自锁托槽组(P<.05)；两组矫治6个月后的龈沟液中IL-1β、TNF-α、AST及ALP含量水平较矫治前有显著提升(P<.05)，但无托槽组显著低于自锁托槽组(P<.05)。结论 无托槽隐形矫治器用于正畸治疗中，能明显改善患者粘戴托槽后的咬合功能，改善牙周组织健康状态，并有效减少龈沟液中IL-1β、TNF-α、AST及ALP过量分泌，以缓解牙周组织炎症状态。     

自锁托槽与双翼托槽滑动法关闭间隙的临床比较

目的：比较3M SmartClip自锁托槽与3M Gemini MBT双翼托槽在拔除第一前磨牙患者使用滑动法关闭间隙的速度。方法选择需拔除第一前磨牙矫治的安氏Ⅰ类错患者20例,采用自身牙弓左右对比的方法,即牙弓一侧第二前磨牙和第一磨牙粘接3M自锁托槽,另一侧粘接Gemini MBT双翼托槽。排齐整平后用0.48 mm ×0.64 mm（0.019英寸×0.025英寸）不锈钢丝及镍钛拉簧关闭间隙,计算关闭间隙的平均速度（mm/月）。结果自锁托槽侧的平均移动速度是1.03 mm/月,传统双翼托槽侧的平均移动速度是1.00 mm/月,差异无统计学意义（t=0.70,P=0.48）。结论3M SmartClip自锁托槽与Gemini MBT双翼托槽滑动法关闭间隙速度没有明显差异。     

自锁托槽直丝弓矫治器的初步应用

自锁托槽以自身所附有的槽沟盖将弓丝固定在槽沟内，改变了传统的结扎丝固位方式，明显地减小了矫治器系统的摩擦力，使牙齿在弱力作用下有效移动。自锁托槽直丝弓矫治器对拔牙矫治、需要较强磨牙支抗、以滑动法关闭间隙的病例有特殊意义。     

一种尖牙控轴直丝托槽的结构设计

目的 设计一种用于错畸形的正畸治疗的新型托槽——尖牙控轴直丝托槽,对其结构设计和应用原理进行探讨分析.方法 定性设计矫治器的结构,托槽两个对角旋转翼与另两个对角翼可以通过旋转轴发生转动,能灵活选择放入弓丝前不锈钢丝结扎托槽与放入弓丝后弹性结扎托槽等结扎方式.结果 设计出一种尖牙正畸控轴直丝托槽,其特征是两对角托槽翼与另两个对角翼可以通过旋转轴发生转动,从而改变托槽槽沟的高度及宽度.结论 使用尖牙控轴托槽时,可以通过结扎尖牙控轴托槽的合龈翼来选择采取不同的矫治系统.     

主动、被动自锁托槽摩擦力的meta分析研究

目的 采用meta分析的方法评价主动自锁托槽与被动自锁托槽摩擦力的大小。方法 检索Pubmed、荷兰医学文摘(Embase)、Google文献检索、中国期刊网(CNKI)和中国生物医学文献数据库(CBMdisc)数据库,搜集从建库至2011年9月公开发表的关于主动、被动自锁托槽摩擦力的随机对照实验。利用Revman4.2软件及Stata 7.0软件对纳入meta分析的研究进行定量分析,以评价主动、被动自锁托槽与不锈钢丝结合时滑动摩擦力的大小。结果 有6项研究适合做meta分析。结果显示:主动、被动自锁托槽在与圆丝结合时,摩擦力的大小没有统计学差异;而与不锈钢方丝结合时主动自锁托槽的摩擦力大于被动自锁托槽,差异具有统计学意义。结论 在矫治初期,主动、被动自锁托槽摩擦力没有统计学差异,而在矫治后期,主动自锁托槽摩擦力大于被动自锁托槽。     

应用Quick自锁托槽与传统结扎式托槽在拔牙矫治中的比较研究

目的 探讨Quick自锁托槽与传统结扎式托槽在拔牙病例矫治中治疗时间和治疗效果方面是否有差异。方法 选择32例需拔牙矫正病例,随机分为2组,分别使用Quick自锁托槽和传统结扎式托槽。记录并分析2组患者排齐整平、关闭间隙和总的治疗时间。每位患者治疗前、后均拍摄头颅定位侧位片,并对治疗前、后的X线头影测量结果进行比较分析。组内、组间均采用配对t检验。 结果 2组患者均获满意矫正效果。2组患者排齐整平、关闭间隙及整个疗程所需时间的差异均没有统计学意义（P＞0.05）。2组间治疗前后的X线头影测量结果中,只有∠SNB和LL-E2组间的差异具有统计学意义（P＜0.05）,其余各项测量指标均无统计学意义（P＞0.05）。结论 Quick自锁托槽与传统结扎式托槽相比,在拔牙病例的疗程和疗效方面并无明显优势。     

无托槽隐形矫治器与固定矫治器对成人骨性Ⅲ类错牙合掩饰治疗的对比研究

目的 观察轻、中度成人骨性Ⅲ类错患者采用隐形矫治与固定矫治器结合微种植体整体远移下牙列治疗前后头影测量变化，评价其临床效果。方法 选取24例轻、中度高角成人骨性Ⅲ类患者按矫治器类型分成两组，均采用微种植体整体远移下牙列完成治疗，对每位患者治疗前后的X线侧位片进行测量分析。结果 所有患者治疗后，磨牙尖牙关系调整至中性，软组织侧貌得到改善。其中隐形矫治组U1-SN增大(9.99±7.74)°、L1-MP减小(1.71±2.96)°、颏唇角减小(2.35±3.02)°，上唇E线距增大(1.01±1.03)°，下唇E线距减小(0.74±0.51)° ；固定矫治组U1-SN增大(8.77±5.45)°、L1-MP减小(3.29±2.26)°、颏唇角减小(2.12±1.74)°，上唇E线距增大(0.52±0.67)°，下唇E线距减小(0.63±0.29)°。隐形矫治组L1-MP (t=1.245，P=0.034)减小量显著低于固定矫治组，且FH-MP (t=2.268，P=0.017)、SNMP (t=4.487，P=0.002)及ANS-Me (t=2.230，P=0.014)增加量显著低于固定矫治组，其余指标变化量组间比较差异无统计学意义。结论 无托槽隐形矫治器结合微种植体支抗整体远移下牙列可以有效纠上下牙矢状向不调，改善患者下颌前凸的的畸形面容，在下前牙转矩控制及垂直向控制上优于传统固定矫治器。     

低摩擦结扎圈在牙齿排齐阶段静摩擦力的实验研究

目的研究低摩擦结扎圈Slide、Neo-Clip和普通结扎丝／圈在牙齿排齐阶段静摩擦力的差异，并与自锁托槽DamonMx和Smartclip比较。材料和方法选取临床牙列拥挤患者的上颌模型制作Typodont，采用MBT普通金属托槽、0．014NT弓丝，在万能测试机上测量不同结扎方式时矫治器系统的静摩擦力。结果Slide结扎时，矫治器系统的静摩擦力与自锁托槽DamonMx和Smartclip之间的差异无显著性，且显著低于Neo-Clip结扎和传统结扎丝／圈结扎。Neo-Clip结扎时矫治器系统静摩擦与Smartclip、普通结扎丝结扎差异无显著性，且显著低于普通结扎圈结扎。结论低摩擦结扎圈在牙齿排齐阶段，可以使矫治器系统静摩擦力降低至自锁托槽水平。     

Friction of conventional and self-ligating brackets using a 10 bracket model

The friction generated by various bracket-archwire combinations previously has been studied using in vitro testing models that included only one or three brackets. This study was performed using a specially designed apparatus that included 10 aligned brackets to compare the frictional resistance generated by conventional stainless steel brackets, self-ligating Damon SL II brackets and Time Plus brackets coupled with stainless steel, nickel-titanium and beta-titanium archwires. All brackets had a 0.022-inch slot, and five different sizes of orthodontic wire alloys used. Each bracket-archwire combination was tested 10 times, and each test was performed with a new bracket-wire sample. Time Plus self-ligating brackets generated significantly lower friction than both the Damon SL II self-ligating brackets and Victory brackets. However, the analysis of the various bracket-archwire combinations showed that Damon SL II brackets generated significantly lower friction than the other brackets when tested with round wires and significantly higher friction than Time Plus when tested with rectangular archwires. Beta-titanium archwires generated higher frictional resistances than the other archwires. All brackets showed higher frictional forces as the wire size increased. These findings suggest that the use of an in vitro testing model that includes 10 brackets can give additional interesting information about the frictional force of the various bracket-archwires combinations to the clinician and the research worker.     

Debris and friction of self-ligating and conventional orthodontic brackets after clinical use

Objective:To compare the degree of debris and friction of conventional and self-ligating orthodontic brackets before and after clinical use.Materials and Methods:Two sets of three conventional and self-ligating brackets were bonded from the first molar to the first premolar in eight individuals, for a total of 16 sets per type of brackets. A passive segment of 0.019 × 0.025-inch stainless steel archwire was inserted into each group of brackets. Frictional force and debris level were evaluated as received and after 8 weeks of intraoral exposure. Two-way analysis of variance and Wilcoxon signed-rank test were applied at P < .05.Results:After the intraoral exposure, there was a significant increase of debris accumulation in both systems of brackets (P < .05). However, the self-ligating brackets showed a higher amount of debris compared with the conventional brackets. The frictional force in conventional brackets was significantly higher when compared with self-ligating brackets before clinical use (P < .001). Clinical exposure for 8 weeks provided a significant increase of friction (P < .001) on both systems. In the self-ligating system, the mean of friction increase was 0.21 N (191%), while 0.52 N (47.2%) was observed for the conventional system.Conclusion:Self-ligating and conventional brackets, when exposed to the intraoral environment, showed a significant increase in frictional force during the sliding mechanics. Debris accumulation was higher for the self-ligating system.     

Comparison of static friction with self-ligating,modified slot design and conventional brackets

Objective

To compare the static frictional forces generated at the bracket/wire interface of stainless steel brackets with different geometries and angulations, combined with orthodontic wires of different diameters.

Material and Methods

The frictional forces were evaluated with three different types of metal brackets: a passive self-ligating (SmartClip^TM, 3M/Unitek, Monrovia, USA), with a modified slot design (Mini Uni Twin^TM, 3M/Unitek, Monrovia, USA) and conventional (Kirium, Abzil, São José do Rio Preto, Brazil). The samples were mounted in a testing device with three different angulations and tested with 0.014" and 0.018" stainless steel wires (American Orthodontics, Sheboygan, USA). The static frictional force was measured using a universal testing machine (DL 500, EMIC^®, São José dos Pinhais, Brazil) with a crosshead speed of 1 mm/min. Statistical analysis was performed by two-way ANOVA followed by Bonferroni''s post hoc test.

Results

There was a significant difference (p<0.05) in static friction when the three types of brackets were tested with the same wire size. The wire diameter influenced friction only when the brackets had a 10º angulation (p<0.05). The angulation influenced friction (p<0.05) when the brackets were associated with a 0.018" wire.

Conclusion

Brackets with a modified slot design showed intermediate static frictional force values between the conventional and self-ligating brackets tested.     

Resistance to sliding of self-ligating brackets versus conventional stainless steel twin brackets with second-order angulation in the dry and wet (saliva) states.

The frictional properties of conventional stainless steel brackets that were coupled with rectangular stainless steel archwires and ligated with stainless steel ligature wires and the frictional properties of closed self-ligating brackets coupled with the same archwires were compared in terms of second-order angulation. The slides of these self-ligating brackets passively restrained the archwires within the slots. As a control, the frictional properties of the opened self-ligating brackets, which were ligated with stainless steel ligature wires, were measured. The resistance to sliding of the conventional brackets and the opened self-ligating brackets were measured at ligation forces ranging from 200 to 600 cN and at angles from -9 degrees to 9 degrees. The resistances to sliding of the closed self-ligating brackets were measured at the same angles, but no external ligation forces were applied. In the passive configuration, the conventional brackets exhibited similar frictional resistance as the opened self-ligating brackets, whereas the closed self-ligating brackets exhibited no friction. In the active configuration, all brackets exhibited increased resistance to sliding as the angulation increased. At all angles, the resistances to sliding of the closed self-ligating brackets were lower than those of the conventional brackets because of the absence of a ligation force when the slide restrained the archwire.     

Evaluation of friction of stainless steel and esthetic self-ligating brackets in various bracket-archwire combinations.

This study measured and compared the level of frictional resistance generated between stainless steel self-ligating brackets (Damon SL II, SDS Ormco, Glendora, Calif), polycarbonate self-ligating brackets (Oyster, Gestenco International, G?thenburg, Sweden), and conventional stainless steel brackets (Victory Series, 3M Unitek, Monrovia, Calif), and 3 different orthodontic wire alloys: stainless steel (Stainless Steel, SDS Ormco), nickel-titanium (Ni-Ti, SDS Ormco), and beta-titanium (TMA, SDS Ormco). All brackets had a.022-in slot, whereas the orthodontic wire alloys were tested in 3 different sections:.016,.017 x.025, and.019 x 0.025 in. Each of the 27 bracket and archwire combinations was tested 10 times, and each test was performed with a new bracket-wire sample. Both static and kinetic friction were measured on a custom-designed apparatus. All data were statistically analyzed (Kruskal-Wallis and Mann Whitney U tests). Stainless steel self-ligating brackets generated significantly lower static and kinetic frictional forces than both conventional stainless steel and polycarbonate self-ligating brackets, which showed no significant differences between them. Beta-titanium archwires had higher frictional resistances than stainless steel and nickel-titanium archwires. No significant differences were found between stainless steel and nickel-titanium archwires. All brackets showed higher static and kinetic frictional forces as the wire size increased.     

国产3B自锁托槽、3B直丝弓托槽和Damon Q自锁托槽椅旁操作时间的对比研究

目的比较国产3B自锁托槽、Damon Q自锁托槽以及国产3B直丝弓托槽的椅旁操作时间,为国产3B自锁托槽的临床应用提供参考依据。方法选择正畸患者80例,其中20人使用国产3B自锁托槽(3B自锁组),20人使用Damon Q自锁托槽(Damon Q自锁组),20人使用国产3B直丝弓托槽+结扎丝结扎(结扎丝组),20人使用国产3B直丝弓托槽+橡皮圈结扎(橡皮圈组)。待患者上下颌牙列基本排齐后,使用0.018*0.025英寸镍钛方丝入槽,记录全口结扎和拆除时间。采用单因素方差分析,比较4组患者的结扎和拆除时间。结果 3B自锁组的结扎、拆除和总时间均明显短于结扎丝组和橡皮圈组(P<0.01)。3B自锁组和Damon Q自锁组在结扎、拆除和总时间方面的差异均无统计学意义(P>0.05)。结论无论是采用结扎丝结扎还是橡皮圈结扎,国产3B自锁托槽的椅旁操作时间明显短于直丝弓托槽,且与进口的Damon Q自锁托槽相比无明显统计学差异。     

Active and passive self-ligation—a myth?

Objective:To compare the frictional behavior of several self-ligating brackets with that of normal brackets both with and without tipping force-moments and in combination with different archwire dimensions.Materials and Methods:The resistance to sliding (RS) of seven self-ligating brackets, a conventional bracket, and a ceramic bracket with a low-friction clip were evaluated in combination with three different archwires and tipping force-moments of 0 and 10 Nmm. The center of rotation for the measurements was set within the center of the bracket or with a 10-mm offset. Resistance to sliding was measured using an Instron 3344 at a cross-head speed of 10 mm/min at a temperature of 36°C.Results:Without a tipping moment, RS increased with the active self-ligating brackets with increasing archwire size. No RS was found for any of the passive self-ligating brackets. The 10-Nmm tipping moment resulted in more RS and was similar for all bracket and archwire combinations. RS was approximately doubled when the center of rotation was located at the bracket rather than with a 10-mm offset.Conclusions:RS between brackets and archwires is highly dependent on the experimental setup. Different setups can result in contradictory results. Almost 1 N of traction force is lost in RS when a moment of 10 Nmm is placed at a rotational center 10 mm from the bracket.     

Resistance to sliding with 3 types of elastomeric modules

INTRODUCTION: Super Slick (TP Orthodontics, LaPorte, Ind), a polymeric-coated ligature, has recently been introduced to the orthodontic market. The manufacturer claims it will significantly reduce friction. The purposes of this study were to determine whether Super Slick modules show lower friction than round and rectangular modules and to put the frictional forces into perspective with a self-ligating bracket. METHODS: Maxillary premolar, stainless steel, self-ligating, and monocrystalline brackets with .022-in slots were used with straight lengths of .018-in and .019 x .025-in stainless steel wires. Buccal segment models were set up with 1 molar band and 2 premolar brackets for each test group: self-ligating brackets with the slide closed, self-ligating brackets with the slide open, and monocrystalline brackets. The latter 2 groups were tested with all 3 types of elastomeric module. Each setup was tested both under dry conditions and after soaking in a water bath for 1 hour. RESULTS: The self-ligating brackets demonstrated virtually zero friction with each combination of wire and environmental condition. When the different bracket and elastomeric module combinations were compared, significant differences were observed. In all but 2 combinations, round modules provided the least resistance to sliding and rectangular modules the greatest, with Super Slick modules in between the 2. The self-ligating bracket provided the least resistance to sliding of all the bracket/ligation combinations and almost entirely eliminated friction under the conditions of this experiment. CONCLUSIONS: Super Slick modules demonstrated greater resistance to sliding than conventional round modules, but not rectangular. Self-ligating brackets provided the least resistance to sliding of all bracket/ligation combinations and were the only method that almost entirely eliminated friction. The .018-in and .019 x .025-in wires exhibited similar friction in the dry state, but, when wet, the .018-in wire produced less friction. Ceramic brackets demonstrated greater resistance to sliding than stainless steel brackets. Lubrication reduced the friction with .018-in wires and increased it for .019 x .025-in wires.     

Quantified simulation of canine retraction: evaluation of frictional resistance

The purpose of this study was to evaluate the frictional resistance of various bracket/archwire combinations. The friction testing apparatus allowed dynamic and progressive bracket tipping and uprighting concurrent with linear bracket traction which experimentally approximated canine retraction with sliding mechanics. Multiple ANOVA using general linear models procedure demonstrated significant effects (P < 0.05) for bracket type, archwire type, archwire size, and archwire shape, as well as pair-wise interactions for bracket type/archwire type, bracket type/archwire size, bracket type/archwire shape, archwire type/archwire size, archwire type/archwire shape, and archwire size/archwire shape. Duncan’s multiple range test (P < 0.05) revealed the general trends regarding frictional performance of brackets and archwires tested, while Least squares means table (P < 0.05) illustrated significant interactions of pair-wise factors that differed from the general trends. It was concluded that: (1) Ceramic brackets with and without metal slots had the greatest friction followed by metal brackets, active self-ligating brackets, variable self-ligating brackets, and passive self-ligating brackets. (2) Stainless steel and braided stainless archwires measured greater friction than nickel-titanium. (3) Smaller dimension wires had less friction than larger wires, and round wires had less friction than rectangular wires. In addition, consideration of specific bracket-archwire coupling appear to reduce the frictional resistance with sliding.