Murakami H, Takehana S, Takenaka M, Abe T
The Third Department of Prosthetic Dentistry, School of Dentistry, Aichi-Gakuin University.
Aichi Gakuin Daigaku Shigakkai Shi. 1990 Dec;28(4):1105-14.
In order to compare the physical properties of the silicone impression materials with regard to their hydrophilicity and hydrophobicity, wetting and water absorption, the surface structure and dimensional changes of stone dies were investigated. The evaluation of wetting was performed on one kind of addition-type material with hydrophilicity, five kinds of addition-type materials with hydrophobicity and one kind of condensation-type silicone impression material. One kind of addition-type silicone impression material with hydrophilicity and hydrophobicity was used in other research. Wetting was assessed by measuring the contact angle between water and the impression materials. Water absorption was assessed by the change in weight of the impression materials after immersion in water. The surface structure of the dental stone was observed by SEM. The dimensional changes of stone dies were measured by means of an apparatus designed in this department. The results were as follows: 1. Wetting: The addition-type impression material with hydrophilicity had a 51.4 +/- 1.3 degree contact angle, and other impression materials varied from 84.6 +/- 6.1 degrees to 97.7 +/- 4.4 degrees. 2. Water absorption: The amount of water absorption of the hydrophilic type was greater than that of the hydrophobic type. 3. The surface structure of dental stone: In the case of Vermix stone, which was poured into water-immersed hydrophilic type material, the stone crystals became large, but Fujirock showed no change. 4. The dimensional change on stone dies: No difference was apparent between the hydrophilic type and the hydrophobicity type. 5. Hydrophilicity may affect the surface structure of the dental stone slightly but this is possible within the permissible clinical limits.
为了比较硅橡胶印模材料在亲水性和疏水性、润湿性和吸水性方面的物理性能，对石膏模型的表面结构和尺寸变化进行了研究。对一种亲水性加成型材料、五种疏水性加成型材料和一种缩合型硅橡胶印模材料进行了润湿性评估。在其他研究中使用了一种兼具亲水性和疏水性的加成型硅橡胶印模材料。通过测量水与印模材料之间的接触角来评估润湿性。通过测量印模材料在水中浸泡后的重量变化来评估吸水性。通过扫描电子显微镜观察牙科石膏的表面结构。使用本部门设计的仪器测量石膏模型的尺寸变化。结果如下：1. 润湿性：亲水性加成型印模材料的接触角为51.4±1.3度，其他印模材料的接触角在84.6±6.1度至97.7±4.4度之间变化。2. 吸水性：亲水性类型的吸水量大于疏水性类型。3. 牙科石膏的表面结构：在倒入浸泡在水中的亲水性材料中的Vermix石膏的情况下，石膏晶体变大，但富士石没有变化。4. 石膏模型上的尺寸变化：亲水性类型和疏水性类型之间没有明显差异。5. 亲水性可能会对牙科石膏的表面结构产生轻微影响，但这在临床允许范围内是可能的。
