Nemec Michael, Bartholomaeus Hans Magnus, H Bertl Michael, Behm Christian, Ali Shokoohi-Tabrizi Hassan, Jonke Erwin, Andrukhov Oleh, Rausch-Fan Xiaohui
Division of Orthodontics, University Clinic of Dentistry, Medical University of Vienna, 1090 Vienna, Austria.
Division of Conservative Dentistry and Periodontology, University Clinic of Dentistry, Medical University of Vienna, 1090 Vienna, Austria.
Materials (Basel). 2020 Nov 24;13(23):5311. doi: 10.3390/ma13235311.
Invisalign aligners have been widely used to correct malocclusions, but their effect on oral cells is poorly known. Previous research evaluated the impact of aligners' eluates on various cells, but the cell behavior in direct contact with aligners is not yet studied. In the present study, we seeded oral epithelial cells (cell line Ca9-22) directly on Invisalign SmartTrack material. This material is composed of polyurethane and co-polyester and exhibit better mechanical characteristics compared to the predecessor. Cell morphology and behavior were investigated by scanning electron microscopy and an optical cell moves analyzer. The effect of aligners on cell proliferation/viability was assessed by cell-counting kit (CCK)-8 and 3,4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT) assay and live/dead staining. The expression of inflammatory markers and proteins involved in epithelial barrier function was measured by qPCR. Cells formed cluster-like structures on aligners. The proliferation/viability of cells growing on aligners was significantly lower ( < 0.05) compared to those growing on tissue culture plastic (TCP). Live/dead staining revealed a rare occurrence of dead cells on aligners. The gene expression level of all inflammatory markers in cells grown on aligners' surfaces was significantly increased ( < 0.05) compared to cells grown on TCP after two days. Gene expression levels of the proteins involved in barrier function significantly increased ( < 0.05) on aligners' surfaces after two and seven days of culture. Aligners' material exhibits no cytotoxic effect on oral epithelial cells, but alters their behavior and the expression of proteins involved in the inflammatory response, and barrier function. The clinical relevance of these effects has still to be established.
隐适美矫治器已被广泛用于矫正错牙合畸形，但其对口腔细胞的影响却鲜为人知。以往的研究评估了矫治器洗脱液对各种细胞的影响，但与矫治器直接接触的细胞行为尚未得到研究。在本研究中，我们将口腔上皮细胞（Ca9-22细胞系）直接接种在隐适美SmartTrack材料上。这种材料由聚氨酯和共聚酯组成，与前代产品相比具有更好的机械性能。通过扫描电子显微镜和光学细胞运动分析仪研究细胞形态和行为。通过细胞计数试剂盒（CCK）-8、3,4,5-二甲基噻唑-2-基-2,5-二苯基四氮唑溴盐（MTT）法和活/死染色评估矫治器对细胞增殖/活力的影响。通过qPCR检测炎症标志物和参与上皮屏障功能的蛋白质的表达。细胞在矫治器上形成簇状结构。与在组织培养塑料（TCP）上生长的细胞相比，在矫治器上生长的细胞的增殖/活力显著降低（<0.05）。活/死染色显示矫治器上死细胞很少见。与在TCP上生长的细胞相比，在矫治器表面生长的细胞中所有炎症标志物的基因表达水平在两天后显著升高（<0.05）。培养两天和七天后，矫治器表面参与屏障功能的蛋白质的基因表达水平显著升高（<0.05）。矫治器材料对口腔上皮细胞无细胞毒性作用，但会改变其行为以及参与炎症反应和屏障功能的蛋白质的表达。这些影响的临床相关性仍有待确定。
