Dergham Carine Abi, Khoury Elie, Ghoubril Joseph
Faculty of Dentistry, Saint-Joseph University of Beirut, Orthodontic Department, Beirut, Lebanon.
Faculty of Dentistry, Saint-Joseph University of Beirut, Orthodontic Department, Beirut, Lebanon.
Int Orthod. 2019 Jun;17(2):202-207. doi: 10.1016/j.ortho.2019.03.001. Epub 2019 Apr 10.
The purpose of this study was to compare the friction of two types of polycrystalline ceramic brackets before and after aging.
A total of 60 second-upper right premolar brackets were divided into two groups: Clarity™ Advanced (3M Unitek, Monrovia, CA) and Clarity™ (3M Unitek). All brackets had a nominal 0.022-in slot size and a McLaughlin Bennett Travesi (MBT) prescription. Each bracket was submitted to a friction test, using the YL01 UTM universal testing machine (YLE GMBH, Germany) before and after thermocycling. All tests were carried out in the presence of artificial saliva, using .019×.025-in. rectangular stainless steel (SS) archwires (3M Unitek). Bracket slot surfaces were observed under an optical microscope (Olympus CX41, Tokyo, Japan) before and after aging.
Before aging, the Clarity Advanced group showed significantly lower friction than the Clarity group (P=0.011). After aging, the friction of the Clarity Advanced bracket decreased significantly (P<0.001), whereas the friction of the Clarity bracket increased significantly (P<0.001). The microscopic qualitative evaluation showed that the slot surfaces of all aged Clarity brackets revealed important pit corrosion when compared with the original brackets.
The new Clarity Advanced ceramic bracket shows good physical friction properties due to the various modifications added by the manufacturers.
本研究旨在比较两种多晶陶瓷托槽老化前后的摩擦力。
总共60个右上第二前磨牙托槽被分为两组：Clarity™ Advanced（3M Unitek，蒙罗维亚，加利福尼亚州）和Clarity™（3M Unitek）。所有托槽的槽沟尺寸标称值为0.022英寸，且采用麦克劳克林·贝内特·特拉维西（MBT）处方。每个托槽在热循环前后使用YL01 UTM万能试验机（YLE GMBH，德国）进行摩擦力测试。所有测试均在人工唾液存在的情况下，使用0.019×0.025英寸的矩形不锈钢（SS）弓丝（3M Unitek）进行。老化前后在光学显微镜（奥林巴斯CX41，东京，日本）下观察托槽槽沟表面。
老化前，Clarity Advanced组的摩擦力显著低于Clarity组（P = 0.011）。老化后，Clarity Advanced托槽的摩擦力显著降低（P < 0.001），而Clarity托槽的摩擦力显著增加（P < 0.001）。微观定性评估显示，与原始托槽相比，所有老化后的Clarity托槽的槽沟表面均出现明显的点蚀。
新型Clarity Advanced陶瓷托槽由于制造商进行的各种改进而具有良好的物理摩擦性能。
