Gracco Antonio, Mazzoli Alida, Favoni Orlando, Conti Carla, Ferraris Paolo, Tosi Giorgio, Guarneri Maria Paola
Department of Orthodontics, University of Ferrara, Italy.
Aust Orthod J. 2009 May;25(1):34-40.
To investigate the short-term optical, chemical and morphological changes in Invisalign appliances.
One 'as-received' Invisalign aligner, one 'as-received' Invisalign aligner immersed in artificial saliva for 14 days and 10 Invisalign aligners worn by 10 randomly selected patients for 14 days were used. Fourier'transform infra-red microspectroscopy was used to characterise any molecular changes on the surfaces of the appliances, spectrophotometry was used to evaluate any changes in colour and transparency, scanning electron microscopy and energy dispersive X-ray microanalysis were used to examine the surface morphology and elemental composition of deposits on the surfaces of the aligners and gas chromatography-mass spectrometry was used to identify substances released from the aligners into the artificial saliva.
Aligners worn for 14 days had microcracks, abraded and delaminated areas, localised calcified biofilm deposits and loss of transparency. Monomers and/or by-products were not released from the aligner suspended in artificial saliva for 14 days, which suggests that the material is chemically stable.
Further studies are required to evaluate how intra-oral conditions may influence the optical properties and chemical stability of the aligners.
研究隐适美矫治器的短期光学、化学和形态学变化。
使用一副“刚收到时”的隐适美矫治器、一副浸泡在人工唾液中14天的“刚收到时”的隐适美矫治器以及10副由10名随机选择的患者佩戴14天的隐适美矫治器。采用傅里叶变换红外显微光谱法对矫治器表面的任何分子变化进行表征，用分光光度法评估颜色和透明度的任何变化，用扫描电子显微镜和能量色散X射线微分析来检查矫治器表面沉积物的表面形态和元素组成，并用气相色谱-质谱法鉴定从矫治器释放到人工唾液中的物质。
佩戴14天的矫治器出现微裂纹、磨损和分层区域、局部钙化生物膜沉积物以及透明度降低。浸泡在人工唾液中14天的矫治器未释放单体和/或副产物，这表明该材料在化学上是稳定的。
需要进一步研究以评估口腔内环境如何影响矫治器的光学性能和化学稳定性。
