Wang H, Chao Y, Liao Y, Sun J
Department of Prosthodontics, School of Stomatology, WCUMS, Chengdu 610041, China.
Hua Xi Yi Ke Da Xue Xue Bao. 2001 Dec;32(4):524-5.
To determine the shrinkage and strength of GI-II Infiltrated Ceramic for providing scientific basis of its clinical use.
The adobes by slip-casting alumina powder of GI-II Infiltrated Ceramic were sintered at 1125 degrees C for 2 hours. The sintered alumina bodies were then divided into two groups and infiltrated by melt glass at 1125 degrees C and 1100 degrees C respectively for 6 hours. The length of the infiltrated ceramic specimens before and after fabrication was determined to calculate shrinkage. Their strength values were obtained by 3-point bending test.
The infiltrated ceramic infiltrated at 1125 degrees C was 0.289 +/- 0.155% in shrinkage, 367.7 +/- 76.1 MPa in strength, and 4.79 in Weibull modulus; that infiltrated at 1100 degrees C was 0.253 +/- 0.043%, 377.5 +/- 64.4 MPa, and 5.52, respectively. There was no statistically significant difference between those two groups. But their strength values were statistically high, compared with 300 MPa.
The shrinkage of GI-II Infiltrated Ceramic could be compensated by brushing spacer on dies and expansion of die stone. Its strength satisfied the requirement for clinical use of all-ceramic bridge materials. This kind of high-strength and low-shrinkage ceramic could be used for fabricating all ceramic crown and bridge core.
测定GI-II渗透陶瓷的收缩率和强度，为其临床应用提供科学依据。
将GI-II渗透陶瓷的氧化铝粉注浆坯体在1125℃烧结2小时。然后将烧结后的氧化铝体分为两组，分别在1125℃和1100℃用熔融玻璃渗透6小时。测定制备前后渗透陶瓷试件的长度以计算收缩率。通过三点弯曲试验获得其强度值。
在1125℃渗透的陶瓷收缩率为0.289±0.155%，强度为367.7±76.1MPa，韦布尔模量为4.79；在1100℃渗透的陶瓷收缩率为0.253±0.043%，强度为377.5±64.4MPa，韦布尔模量为5.52。两组之间无统计学显著差异。但与300MPa相比，其强度值在统计学上较高。
GI-II渗透陶瓷的收缩率可通过在代型上涂抹间隔剂和使用膨胀石膏来补偿。其强度满足全瓷桥材料临床应用的要求。这种高强度、低收缩率的陶瓷可用于制作全瓷冠和桥核。
