Karimjee C K, Koka S, Rallis D M, Gound T G
Endodontics, Department of Surgical Specialties, University of Nebraska Medical Center College of Dentistry, Lincoln, NE, USA.
Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2006 Oct;102(4):e115-20. doi: 10.1016/j.tripleo.2005.12.020. Epub 2006 Jul 14.
Mineral trioxide aggregate (MTA) mixed with water has a short working time, delayed setting, and poor consistency. A preliminary study suggested that substituting KY Jelly as a mixing vehicle improves the working properties of MTA. The present study compared the biocompatibility of white MTA mixed with water or with KY Jelly to that of Fuji II cement and of silver amalgam.
Periodontal ligament (PDL) cells were cultured using standard laboratory procedures. Cells were plated in wells at a density of 10,000 cells/well. The test materials were mixed and eluate placed in contact with the PDL cells. Cell viability was determined by measuring mitochondrial enzyme activity using the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenytl)-2H-tetrazolium inner salt assay. Cytotoxicity was also measured in terms of cell lysis using the lactate dehydrogenase assay. The assays were completed in triplicate after time intervals of 24, 48, and 72 h. Mean cell counts were calculated and converted to a percentage of control results. A 2-way analysis of variance and Tukey honestly significant difference post-hoc test were performed to determine statistical significance.
Eluate extractions from all materials caused significantly less cell viability and more cell death than control eluate (medium only) at all eluate time points tested. However, at 72 h the MTA/water, MTA/KY, and amalgam eluate extractions led to significantly better cell viability than the Fuji II eluates. However, there was significantly greater cell lysis for all eluates from the tested materials at 72 h than at 24 h.
Within the limitations of this in vitro study, we conclude that MTA/KY, MTA/water, and amalgam have similar biocompatibility regarding effects of their eluates on human PDL cells, and eluates from all 3 materials demonstrate better biocompatibility than eluates derived from a resin-modified glass ionomer cement.
与水混合的三氧化矿物凝聚体（MTA）操作时间短、凝固延迟且稠度不佳。一项初步研究表明，用KY胶冻作为混合媒介可改善MTA的操作性能。本研究比较了与水或与KY胶冻混合的白色MTA、富士II型水门汀及银汞合金的生物相容性。
采用标准实验室程序培养牙周膜（PDL）细胞。将细胞以每孔10,000个细胞的密度接种于孔板中。将测试材料混合，其洗脱液与PDL细胞接触。使用3-(4,5-二甲基噻唑-2-基)-5-(3-羧基甲氧基苯基)-2-(4-磺基苯基)-2H-四唑内盐法通过测量线粒体酶活性来确定细胞活力。还使用乳酸脱氢酶法根据细胞裂解情况来测量细胞毒性。在24、48和72小时的时间间隔后，一式三份完成检测。计算平均细胞计数并换算为对照结果的百分比。进行双向方差分析和Tukey真实显著性差异事后检验以确定统计学显著性。
在所有测试的洗脱液时间点，所有材料的洗脱液提取物导致的细胞活力明显低于对照洗脱液（仅培养基），且细胞死亡更多。然而，在72小时时，MTA/水、MTA/KY和银汞合金洗脱液提取物导致的细胞活力明显优于富士II型洗脱液。然而，在72小时时，所有测试材料洗脱液的细胞裂解明显多于24小时时。
在本体外研究的局限性内，我们得出结论，MTA/KY、MTA/水和银汞合金在其洗脱液对人PDL细胞的影响方面具有相似的生物相容性，并且这三种材料的洗脱液均显示出比树脂改性玻璃离子水门汀的洗脱液更好的生物相容性。
