Lubricating conditions: effects on friction between orthodontic brackets and archwires with different cross-sections

Abstract Objective: This study investigated the effect of the condition of lubrication on the friction between brackets and NiTi archwires of different rounded cross-sections. Methods: Brackets (Roth, GAC) were affixed to a device connected to a universal testing machine into which segments of archwire were placed (NiTi, Nitinol, GAC) with cross-sections of 0.012-in, 0.016-in and 0.020-in. Once the wire was in the bracket slot, the following lubricants were applied: human saliva (HS: positive control), distilled water (DI), mucin-based (MUC) or carboxymethylcellulose-based (CMC) artificial saliva. In the negative control group, no lubricant was used. The combination between the wire cross-sections and the lubrication condition generated 15 groups with 15 samples each. Data were submitted to two-way analysis of variance and Tukey’s test. Results: There was no significant interaction between the wire cross-section and the condition of lubrication (p= 0.901). Irrespective of whether lubricants were used or not, there was a significant increase in friction with an increase in the cross-section of the wire (p

摘要与研究目的：本研究探究了润滑状态对不同圆角截面镍钛（NiTi）弓丝与托槽之间摩擦力的影响。方法：将Roth、GAC品牌的托槽固定于与万能试验机相连的装置中，并置入截面规格为0.012英寸、0.016英寸及0.020英寸的GAC品牌镍钛（NiTi，Nitinol）弓丝段。当弓丝置入托槽槽沟后，分别施加以下润滑剂：人类唾液（HS，阳性对照）、蒸馏水（DI）、黏蛋白基（MUC）人工唾液或羧甲基纤维素基（CMC）人工唾液；阴性对照组不施加任何润滑剂。弓丝截面与润滑状态的组合共生成15组实验，每组含15个样本。实验数据采用双因素方差分析与Tukey检验进行统计处理。结果：弓丝截面与润滑状态之间无显著交互作用（p=0.901）。无论是否使用润滑剂，弓丝截面增大均会导致摩擦力显著升高（p