Hu J, Zou X Y, Zhuang H, Gao X J
1. Department of Cariology and Endodontology, Peking University School and Hospital of Stomatology & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology, Beijing 100081, China; 2. School of Stomatology,Fujian Medical University,Fuzhou 350002, China.
Department of Cariology and Endodontology, Peking University School and Hospital of Stomatology & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology, Beijing 100081, China.
Beijing Da Xue Xue Bao Yi Xue Ban. 2016 Oct 18;48(5):871-877.
To compare the effects of three root canal sealers with respect to time on biocompatibility of human periodontal ligament cells (hPDLCs).The sealers included zinc oxide and eugenol based sealers (ZOE), epoxy resin sealers (ERS) and silicone based sealers (SBS).
hPDLCs were primarily cultured,with the method combining of tissue explant and enzymatic digestion. The cells were then exposed to different extract fluids: (1) ZOE extracted for 24 h group ;(2) ZOE extracted for 1 week group;(3)ZOE extracted for 2 weeks group;(4) ERS extracted after 24 h group; (5) ERS extracted after 1 week group; (6) ERS extracted after 2 weeks group; (7) SBS extracted after 24 h group; (8) SBS extracted after 1 week group; (9) SBS extracted after 2 weeks group; (10) Dulbecco modified Eagle's medium/F12 (DMEM/F12) as negative control group. Cell morphology was observed under an inverted microscope.Cell proliferation was measured by methyl-thiazol-diphenyltetrazolium (MTT) assay. ALP assay kit was used for measuring alkaline phosphatase (ALP) activity. Sealers of 2 weeks' setting time were then immersed in an osteogenic medium for examination of mineral nodules and calcium deposits.
Considering the relative growth rate(RGR),ZOE was severely to moderately cytotoxic(RGR:13.6%-39.9%), while ERS was slightly or not cytotoxic (RGR: 87.6%-95.3%).Only SBS did not show any cytotoxicity after setting (RGR: 91.8%-106.7%). The setting time influenced the cytotoxicity of ERS which decreased after 1 week. Considering the ALP activity,there was no difference between SBS group and control group (F=3.397,P=0.053). According to the results of calcium deposits, ZOE:D562 nm=0.180±0.050,ERS: D562 nm=2.968±0.201,SBS:D562 nm=3.623±0.039,Control:D562 nm=3.477±0.102,the ranking of ALP activity and calcium deposits was as follows: ZOE<ERS <SBS=Control.
The cytotoxicity of ZOE was the highest and persisted with time. The setting time had influence on the cytotoxicity of ERS. Only SBS did not show any cytotoxicity or inhibition of the mineral potential on hPDLCs, indicating which was more biocompatible than the others.
比较三种根管封闭剂在不同时间对人牙周膜细胞（hPDLCs）生物相容性的影响。这三种封闭剂分别是氧化锌丁香酚类封闭剂（ZOE）、环氧树脂类封闭剂（ERS）和硅酮类封闭剂（SBS）。
采用组织块法和酶消化法相结合的方式对hPDLCs进行原代培养。然后将细胞暴露于不同的提取液中：（1）ZOE提取24小时组；（2）ZOE提取1周组；（3）ZOE提取2周组；（4）ERS提取24小时后组；（5）ERS提取1周后组；（6）ERS提取2周后组；（7）SBS提取24小时后组；（8）SBS提取1周后组；（9）SBS提取2周后组；（10）杜尔贝科改良伊格尔培养基/F12（DMEM/F12）作为阴性对照组。在倒置显微镜下观察细胞形态。采用甲基噻唑基二苯基四氮唑溴盐（MTT）法检测细胞增殖。使用碱性磷酸酶（ALP）检测试剂盒测量碱性磷酸酶活性。将凝固2周的封闭剂浸泡在成骨培养基中，检测矿化结节和钙沉积情况。
就相对生长率（RGR）而言，ZOE具有重度至中度细胞毒性（RGR：13.6%-39.9%），而ERS具有轻度或无细胞毒性（RGR：87.6%-95.3%）。只有SBS凝固后未显示任何细胞毒性（RGR：91.8%-106.7%）。凝固时间影响ERS的细胞毒性，1周后其细胞毒性降低。就ALP活性而言，SBS组与对照组之间无差异（F=3.397，P=0.053）。根据钙沉积结果，ZOE：D562nm=0.180±0.050，ERS：D562nm=2.968±0.201，SBS：D562nm=3.623±0.039，对照组：D562nm=3.477±0.102，ALP活性和钙沉积的排序如下：ZOE＜ERS＜SBS=对照组。
ZOE的细胞毒性最高，且随时间持续存在。凝固时间对ERS的细胞毒性有影响。只有SBS对hPDLCs未显示任何细胞毒性或对矿化潜能的抑制作用，表明其比其他封闭剂具有更高的生物相容性。
