Shrivastava Kirti Jajoo, Bhoyar Anjali, Agarwal Surendra, Shrivastava Saurabh, Parlani Swapnil, Murthy Varsha
Department of Prosthodontics, People's Dental Academy, Bhopal, Madhya Pradesh, India.
Department of Prosthodontics, People's College of Dental Sciences, Bhopal, Madhya Pradesh, India.
J Nat Sci Biol Med. 2015 Aug;6(Suppl 1):S53-7. doi: 10.4103/0976-9668.166082.
We compared the clinical efficacy of three gingival displacement systems to accurately record intra-crevicular margins of tooth preparation.
One mechanical (magic foam cord) and two chemico-mechanical (expasyl paste and retraction cord impregnated with 15% aluminum chloride) gingival displacement systems were used. This study was conducted on the maxillary central incisors of 20 patients (20-60 years old) requiring full coverage restoration. All the three gingival displacement systems were tested in three sessions at an interval of 14 days in same order. The casts were sectioned and viewed under an optical microscope, followed by quantitative measurements of the width of the pre and postretracted sulci.
All the three displacement systems produced highly significant horizontal gingival displacement. Retraction cord soaked in 15% aluminum chloride produced maximum displacement (0.74 mm), followed by expasyl paste (0.48 mm) whereas magic foam cord produced the least displacement (0.41 mm).
Gingival displacement shown by each displacement system was found to be more than the accepted value necessary for elastomeric impression accuracy (0.2 mm) to record intra-crevicular margins of tooth preparation.
我们比较了三种牙龈退缩系统在准确记录牙体预备龈沟内边缘方面的临床疗效。
使用一种机械性(魔术泡沫线)和两种化学机械性(排龈膏和浸渍15%氯化铝的排龈线)牙龈退缩系统。本研究针对20例(年龄20 - 60岁)需要全冠修复的患者的上颌中切牙进行。所有三种牙龈退缩系统按相同顺序在三个阶段进行测试,间隔14天。将模型切片并在光学显微镜下观察,随后对退缩前后龈沟宽度进行定量测量。
所有三种退缩系统均产生了高度显著的水平牙龈退缩。浸渍15%氯化铝的排龈线产生的退缩量最大(0.74毫米),其次是排龈膏(0.48毫米),而魔术泡沫线产生的退缩量最小(0.41毫米)。
发现每种退缩系统所显示的牙龈退缩量均超过了弹性印模记录牙体预备龈沟内边缘所需的公认值(0.2毫米)。