[正畸牵引对牙釉质微观结构的影响]
[Effect of orthodontic traction on the microstructure of dental enamel].
作者信息
Li Zhixin, Zhang Kailiang, Li Ruiping, Xu Lingdan, He Lulu, Pang Xiaochan, Lu Jiyuan, Cao Baocheng, Zhang Baoping
机构信息
School of Stomatology, Lanzhou University, Lanzhou 730000, China.
Department of Prosthodontics, Hospital of Stomatology, Lanzhou University, Lanzhou 730000, China.
出版信息
Nan Fang Yi Ke Da Xue Xue Bao. 2020 Aug 30;40(8):1165-1171. doi: 10.12122/j.issn.1673-4254.2020.08.14.
OBJECTIVE
To investigate the effect of orthodontic traction on the microstructure of dental enamel.
METHODS
Forty-eight isolated premolars were randomly divided into 6 groups (=8), including Group A (blank control group), in which the teeth were bonded with the orthodontic brackets without any loading force; Groups B1, B2, and B3 where the teeth were bonded with the orthodontic brackets using clinical adhesives and loaded with 50 g force for 6 months, 200 g force for 6 months, and 200 g force for 1 month, respectively; and Groups C1 and C2, where the teeth were bonded with straight wire brackets using light curing bonding and chemical curing bonding techniques, respectively. All the teeth were embedded with non-decalcified epoxy resin. Scanning electron microscope (SEM), atomic force microscope (AFM), and energy spectrometer (EDS) were used to analyze interface morphology and elemental composition of the teeth sliced with a hard tissue microtome.
RESULTS
Compared with those in Group A, the teeth in the other 5 groups showed increased adhesive residue index with microcracks and void structures on the enamel surface under SEM; AFM revealed microcracks on the enamel surface with angles to the grinding direction. A larger loading force on the bracket resulted in more microcracks on the enamel interface. The interface roughness differed significantly between Groups A and C2, and the peak-to-valley distance differed significantly between Groups A, C, and C2.
CONCLUSIONS
Orthodontic traction can cause changes in the microstructure of normal dental enamel.
目的
研究正畸牵引对牙釉质微观结构的影响。
方法
将48颗离体前磨牙随机分为6组（每组8颗），包括A组（空白对照组），该组牙齿粘结正畸托槽但未施加任何加载力；B1、B2和B3组，牙齿分别使用临床粘结剂粘结正畸托槽，并分别施加50 g力持续6个月、200 g力持续6个月和200 g力持续1个月；C1和C2组，牙齿分别使用光固化粘结技术和化学固化粘结技术粘结直丝托槽。所有牙齿均用非脱钙环氧树脂包埋。使用扫描电子显微镜（SEM）、原子力显微镜（AFM）和能谱仪（EDS）分析用硬组织切片机切片后的牙齿的界面形态和元素组成。
结果
与A组相比，其他5组牙齿的粘结残留指数增加，SEM下釉质表面可见微裂纹和孔隙结构；AFM显示釉质表面有与研磨方向成一定角度的微裂纹。托槽上较大的加载力导致釉质界面出现更多微裂纹。A组和C2组之间界面粗糙度差异显著，A组、C1组和C2组之间峰谷距离差异显著。
结论
正畸牵引可导致正常牙釉质微观结构发生改变。
Zotero 插件