Adl Alireza, Motamedifar Mohammad, Shams Mahdi Sedigh, Mirzaie Ahmad
Department of Endodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
Aust Endod J. 2015 Apr;41(1):12-6. doi: 10.1111/aej.12054. Epub 2013 Dec 13.
The purpose of this clinical study was to determine the effect of 7 day intracanal dressing with calcium hydroxide on the amount of bacterial lipopolysaccharide (LPS; endotoxin) in human teeth with necrotic and infected pulp and apical periodontitis. Twenty-five single-rooted teeth with necrotic pulps and apical periodontitis were selected. Samples were collected before (S1), after root canal preparation (S2) and after 7 day intracanal dressing with calcium hydroxide (S3). The limulus amoebocyte lysate assay was used to quantify LPS. LPS was present in 100% of the root canals before (S1), after preparation (S2) and after 7 day intracanal dressing (S3). A significant reduction, equal to 29.54%, was found after root canal preparation (P < 0.05). A significant difference (equal to 25.26% reduction) was also detected between S2 and S3 (P < 0.05). Total endotoxin reduction (S3 compared with S1) was found to be 47.34%. Endotoxin concentration of the infected root canals was reduced after root canal preparation and also after 7 days of dressing of canals with calcium hydroxide; however, relatively high values of endotoxin remained in the root canals.
本临床研究的目的是确定用氢氧化钙进行7天根管内封药对患有坏死感染牙髓及根尖周炎的人牙齿中细菌脂多糖（LPS；内毒素）含量的影响。选取了25颗患有坏死牙髓及根尖周炎的单根牙。在根管预备前（S1）、根管预备后（S2）以及用氢氧化钙进行7天根管内封药后（S3）采集样本。采用鲎试剂法对LPS进行定量。在根管预备前（S1）、预备后（S2）以及7天根管内封药后（S3），100%的根管中均存在LPS。根管预备后LPS含量显著降低，降幅达29.54%（P < 0.05）。在S2和S3之间也检测到显著差异（降幅为25.26%）（P < 0.05）。与S1相比，S3时内毒素总量降低了47.34%。根管预备后以及用氢氧化钙对根管封药7天后，感染根管的内毒素浓度均有所降低；然而，根管内仍残留相对较高水平的内毒素。
