Invisalign隐形矫治器材料理化性能变化的短期研究

Short-term study of physical and chemical changes in Invisalign appliances

目的在患者口腔内及体外模拟口腔环境研究Invisalign隐形矫治器材料使用前后的理化性能变化。方法选取进行Invisalign隐形矫治的5名患者,回收佩戴14 d后的矫治器5副,作为口内使用组;选取相同患者未使用的隐形矫治器5副,口外模拟口腔环境浸泡14 d,作为口外模拟组;选取相同患者未使用的形矫治器5副,作为空白对照组。使用扫描电子显微镜观察材料表面形貌的改变,能谱仪检测材料表面元素组成变化,傅立叶红外检测材料官能基团的改变。结果 Invisalign隐形矫治器材料表面平整,为锆增韧纳米级有机聚合材料;在患者口腔环境使用14 d后,材料表面较粗糙,可见散在钙化沉积物,部分区域可见裂纹、磨损与分层,有菌斑附着;体外模拟口腔环境浸泡14 d后,材料表面可见散在沉积物与少量菌斑,但未见磨损、裂纹及分层区域。傅立叶红外光谱显示材料吸收峰集中在3 600~2 700 cm-1与1 900~600 cm-1两个波段,口腔内使用及体外模拟口腔环境浸泡后,材料红外吸收特征光谱未发生明显变化。结论 Invisalign隐形矫治器材料短期内理化性能较为稳定,但需注意控制菌斑。

Objective To investigate the short-term physical and chemical property changes of Invisalign invisible ap- pliance before and after used by patients and immersed in simulated oral environment. Methods Five patients undergo- ing Invisalign invisible orthodontic treatment were randomly selected, and their orthodontic appliances after wearing for 14 d were collected as intraoral used group. Their unused orthodontic appliances, immersing in simulated body fluid to mimic intro-oral environment and without any treatment, were collected as simulated and control group, respectively. Sur- face morphology changes and elemental composition variation were detected by the Scanning Electron Microscopy （SEM） with an Energy Dispersive Spectrometer （EDS）. Molecular and functional groups changes were examined by Fourier transform infrared spectrometer. Results The zireonia toughened nanoscale organic polymeric material with a smooth surface of lnvisalign appliance was confirmed by SEM and EDS. The surface of Invisalign appliance worn for 14 d became rough was observed, and micro-cracks, delaminated areas and localized calcified biofilm deposits were also detected. While, after soaking in artificial saliva for 14 d, scattered sediment with a small amount of plaque were detected. Howev- er, no wear, cracks and stratified area were existed on material surface. Fourier Transform infrared spectroscopy （FTIR） revealed that main adsorption peaks of the material were at 3 600 - 2 700 cm - ~ and 1 900 ~ 600 cm - J, and there were no changes of molecular structurebefore and after used . Conclusion Bacterial colonization was confirmed on Invisalign in- visible appliance surface after wearing for 14 d, however, no sign^cant changes of molecular structure of lnvisalign mate- rial were confirmed by FTIR. Scattered crystalline sediments were formed on both intraoral used and simulated immersion materials.