Gordon G E, Johnson G H, Drennon D G
Department of Restorative Dentistry, University of Washington, School of Dentistry, Seattle.
J Prosthet Dent. 1990 Jan;63(1):12-5. doi: 10.1016/0022-3913(90)90257-d.
This study evaluated the accuracy of reproduction of stone casts made from impressions using different tray and impression materials. The tray materials used were an acrylic resin, a thermoplastic, and a plastic. The impression materials used were an additional silicone, a polyether, and a polysulfide. Impressions were made of a stainless steel master die that simulated crown preparations for a fixed partial denture and an acrylic resin model with cross-arch and anteroposterior landmarks in stainless steel that typify clinical intra-arch distances. Impressions of the fixed partial denture simulation were made with all three impression materials and all three tray types. Impressions of the cross-arch and anteroposterior landmarks were made by using all three tray types with only the addition reaction silicone impression material. Impressions were poured at 1 hour with a type IV dental stone. Data were analyzed by using ANOVA with a sample size of five. Results indicated that custom-made trays of acrylic resin and the thermoplastic material performed similarly regarding die accuracy and produced clinically acceptable casts. The stock plastic tray consistently produced casts with greater dimensional change than the two custom trays.
本研究评估了使用不同托盘和印模材料由印模制作的石膏模型的复制准确性。所用的托盘材料为一种丙烯酸树脂、一种热塑性塑料和一种塑料。所用的印模材料为一种加成型硅橡胶、一种聚醚和一种多硫化物。印模取自一个模拟固定局部义齿牙冠预备的不锈钢主模型以及一个带有典型临床牙弓内距离的不锈钢制的带有跨牙弓和前后标志的丙烯酸树脂模型。使用所有三种印模材料和所有三种托盘类型制作固定局部义齿模拟的印模。使用所有三种托盘类型，仅用加成型硅橡胶印模材料制作跨牙弓和前后标志的印模。1小时后用IV型牙科石膏灌注印模。采用样本量为5的方差分析对数据进行分析。结果表明，丙烯酸树脂定制托盘和热塑性材料托盘在模型准确性方面表现相似，并且制作出临床上可接受的模型。成品塑料托盘制作的模型始终比两个定制托盘产生更大的尺寸变化。
