Yoldaş O, Doğan C, Seydaoğlu G
Department of Conservative Dentistry and Endodontics, Faculty of Dentistry, University of Cukurova, Adana, Turkey.
Int Endod J. 2004 Dec;37(12):828-31. doi: 10.1111/j.1365-2591.2004.00885.x.
To evaluate the effect of a calcium hydroxide and glycerine mix and a calcium hydroxide and water mix on the microhardness of human root dentine.
Eleven freshly extracted maxillary canine and central incisor teeth were used. The teeth were sectioned transversally to produce a total of 22 dentine discs from the middle-third of the root. The specimens were divided into two groups of 11 discs each. Dentine samples were treated with either a Ca(OH)2-glycerine combination or a Ca(OH)2-distilled water combination for 1, 3 and 7 days. Dentine microhardness was measured with a Knoop indenter with a load of 100 g for 15 s before and during the experimental period. Each root disc received a series of three indentations around the pulp space, 1 mm from canal wall.
Statistical analysis showed that both combinations significantly decreased dentine microhardness after 3 and 7 days (P < 0.01). The reduction in dentine microhardness following the use of a Ca(OH)2-glycerine combination was significantly greater than that after a Ca(OH)2-distilled water combination after 3 and 7 days (P < 0.01).
The use of Ca(OH)2 combinations for intracanal dressing softens dentine.
评估氢氧化钙与甘油混合物以及氢氧化钙与水混合物对人牙根牙本质显微硬度的影响。
使用11颗新鲜拔除的上颌尖牙和中切牙。将牙齿横向切片，从牙根中部三分之一处共制作出22个牙本质圆盘。标本被分为两组，每组11个圆盘。牙本质样本分别用氢氧化钙 - 甘油组合或氢氧化钙 - 蒸馏水组合处理1天、3天和7天。在实验期之前和期间，使用努氏压头，在100克载荷下保持15秒来测量牙本质显微硬度。每个牙根圆盘在距根管壁1毫米处围绕牙髓腔接受一系列三个压痕。
统计分析表明，两种组合在3天和7天后均显著降低了牙本质显微硬度（P < 0.01）。在3天和7天后，使用氢氧化钙 - 甘油组合后牙本质显微硬度的降低显著大于使用氢氧化钙 - 蒸馏水组合后的降低（P < 0.01）。
根管内封药使用氢氧化钙组合会使牙本质软化。
