Brackett M G, Marshall A, Lockwood P E, Lewis J B, Messer R L W, Bouillaguet S, Wataha J C
Department of Oral Rehabilitation, Medical College of Georgia School of Dentistry, Augusta, GA 30912-1260, USA.
Int Endod J. 2008 Dec;41(12):1072-8. doi: 10.1111/j.1365-2591.2008.01471.x.
To test the hypothesis that extending the time of a traditional ex vivo cytotoxicity test helps to identify trends in the behaviour of root core materials and sealers, which could ultimately aid in predicting their clinical safety and performance.
Endodontic sealers and core specimens were initially tested in direct contact with L929 fibroblasts for 72 h. Cell response was estimated by measuring cellular succinate dehydrogenase activity relative to Teflon controls. Cytotoxicity (% of more active cells) was reassessed after 1, 3, 4 and 6 weeks, with the specimens stored in a physiologically balanced salt-solution between tests.
Distinct trends in cytotoxicity among both core materials and sealers were observed over the 6-week test. Four of the six sealers and two of the three core materials showed cell viabilities of <30% of Teflon after 6 weeks (>70% cytotoxicity).
The current results suggest that some endodontic materials have an elevated biological risk for extended intervals.
验证如下假设,即延长传统体外细胞毒性试验的时间有助于确定根管桩核材料与封闭剂的行为趋势,这最终可能有助于预测它们的临床安全性和性能。
首先将牙髓封闭剂和桩核标本与L929成纤维细胞直接接触进行72小时试验。通过测量相对于聚四氟乙烯对照的细胞琥珀酸脱氢酶活性来评估细胞反应。在1、3、4和6周后重新评估细胞毒性(活性更高的细胞百分比),试验之间将标本保存在生理平衡盐溶液中。
在为期6周的试验中,观察到桩核材料和封闭剂的细胞毒性存在明显趋势。六种封闭剂中的四种以及三种桩核材料中的两种在6周后显示细胞活力低于聚四氟乙烯的30%(细胞毒性>70%)。
目前的结果表明,一些牙髓材料在较长时间内具有较高的生物风险。