Mansoura University, Faculty of Dentistry, Orthodontic Department (Mansoura/Egypt).
University of Bonn, Department of Oral Technology, School of Dentistry (Bonn/Germany).
Dental Press J Orthod. 2022 Jul 4;27(3):e2220489. doi: 10.1590/2177-6709.27.3.e2220489.oar. eCollection 2022.
To evaluate, in-vitro, the change in crown inclination that occurs during orthodontic leveling and alignment using different archwire-bracket-ligation combinations.
Four archwire types were tested: (1) 0.012-in stainless steel and (2) 0.0155-in stainless steel multi-stranded, (3) 0.012-in nitinol Orthonol® and (4) 0.012-in nitinol Thermalloy®. Combinations with five types of 0.022-in slot orthodontic brackets were tested: SmartClipTM and Time3® self-ligating brackets, Mini-Taurus® and Victory SeriesTM conventional brackets, and Synergy® conventional-low friction bracket. Conventional brackets were ligated with both stainless steel and elastomeric ligatures. The simulated malocclusion comprised 2.0mm gingival and 2.0mm labial displacements of a maxillary right central incisor. Rotation around the Y-axis (representing labio-palatal inclination) was measured for the different archwire-bracket-ligation combinations.
The largest rotation was measured whith Orthonol® and Thermalloy® wires when combined with SmartClipTM brackets (8.07±0.24º and 8.06±0.26º, respectively) and with Synergy® brackets ligated with stainless steel ligatures (8.03±0.49º and 8.0±0.37º, respectively). The lower rotation was recorded when Thermalloy®, multi-stranded, and Orthonol® wires were ligated with elastomeric rings to Mini-Taurus® brackets (1.53±0.18º, 1.65± 0.23º and 1.70±0.28º, respectively) and to Victory SeriesTM brackets (1.68± 0.78º, 2.92± 1.40º and 1.74±0.46º, respectively).
All archwire-bracket-ligation combinations produced lingual crown inclination; however, lower changes were observed when the conventional brackets were ligated with elastomeric rings. The multi-stranded archwire produced less rotation with nearly every bracket-ligation combination, compared to the other archwires. The effect of the archwire-bracket-ligation combination on tooth inclination during leveling and alignment should be considered during planning treatment mechanics.
通过体外实验评估不同弓丝-托槽-结扎组合在正畸排齐整平过程中牙冠倾斜度的变化。
测试了四种弓丝类型：（1）0.012 英寸不锈钢和（2）0.0155 英寸不锈钢多股，（3）0.012 英寸镍钛诺 Orthonol®和（4）0.012 英寸镍钛诺 Thermalloy®。测试了五种 0.022 英寸槽正畸托槽的组合：SmartClipTM和 Time3®自结扎托槽、Mini-Taurus®和 Victory SeriesTM传统托槽以及 Synergy®传统低摩擦托槽。传统托槽用不锈钢结扎丝和弹性结扎丝结扎。模拟错牙合包括上颌右侧中切牙牙龈 2.0mm 和唇侧 2.0mm 移位。测量不同弓丝-托槽-结扎组合的 Y 轴（代表唇腭倾斜）旋转。
当 Orthonol®和 Thermalloy®丝与 SmartClipTM托槽结合时，测量到的旋转最大（分别为 8.07±0.24º和 8.06±0.26º），当与 Synergy®托槽和不锈钢结扎丝结合时，旋转最大（分别为 8.03±0.49º和 8.0±0.37º）。当 Thermalloy®、多股和 Orthonol®丝用弹性环结扎到 Mini-Taurus®托槽（分别为 1.53±0.18º、1.65±0.23º和 1.70±0.28º）和 Victory SeriesTM托槽（分别为 1.68±0.78º、2.92±1.40º和 1.74±0.46º）时，记录到的旋转最小。
所有弓丝-托槽-结扎组合都产生了舌倾牙冠倾斜，但当传统托槽用弹性环结扎时，变化较小。与其他弓丝相比，多股弓丝与几乎所有托槽-结扎组合的旋转都较小。在计划治疗力学时，应考虑弓丝-托槽-结扎组合对牙齿在排齐整平过程中倾斜度的影响。
