Objectives: This work aimed to synthesize a novel injectable alginate impression material and evaluate its accuracy.
Methods: Certain proportions of sodium alginate, trisodium phosphate dodecahydrate, potassium fluorotitanate, diatomaceous earth, and other ingredients were dissolved in water and mixed evenly with a planetary centrifugal mixer to obtain a certain viscosity base paste. Certain proportions of calcium sulfate hemihydrate, magnesium oxide, glycerin, and polyethylene glycol (PEG) 400 were mixed evenly with a planetary centrifugal mixer to obtain the reactor paste with the same viscosity as the base paste. The base and reactor pastes were poured into a two-cylinder cartridge at a 2∶1 volume ratio. A gun device was used to accomplish mixing by compressing materials into a mixing tip. The samples were divided into three groups: injectable alginate impression materials (IA group) as the experimental group, and Jeltrate alginate impression materials (JA group) and Silagum-putty/light addition silicone rubber impression materials (SI group) as the two control groups.
Results: Scanning electron microscopy (SEM) showed that the injectable alginate impression materials had a denser structure and fewer bubbles than the commercial alginate impression material. The accuracy of the three kinds of impression materials was evaluated by 3D image superposition. The deviations between the three test group models and the standard model (trueness) were 49.58 μm±1.453 μm (IA group), 54.75 μm±7.264 μm (JA group), and 30.92 μm±1.013 μm (SI group). The deviations of the models within each test group (precision) were 85.79 μm±8.191 μm (IA group), 97.65 μm±11.060 μm (JA group), and 56.51 μm±4.995 μm (SI group). Significant differences in trueness and precision were found among the three kinds of impression materials (P<0.05).
Conclusions: The accuracy of the new injectable alginate impression material was better than that of the traditional powder-type alginate impression material but worse than that of the addition silicone rubber impression materials. The novel injec-table alginate impression material demonstrated good operation performance and impression accuracy, showing broad application prospect.
目的: 研制一种新型可注射型藻酸盐印模材料，评价其准确性。方法: 将一定比例的海藻酸钠、磷酸三钠、氟钛酸钾、硅藻土等成分用水溶解，行星离心搅拌机混合均匀，获得一定黏度的基质组分；将一定比例半水硫酸钙、氧化镁、甘油、聚乙二醇（PEG）400离心搅拌机混合均匀，获得同样黏度的胶结剂组分。基质组分与胶结剂组分封装在2∶1体积比的A/B胶管内。使用时用与A/B胶管匹配的注射枪和混合头加压混合。样本分为3组：以注射型藻酸盐印模材料（IA组）作为实验组，Jeltrate藻酸盐印模材料（JA组）和Silagum-putty/light加成型硅橡胶印模材料（SI组）为对照。通过扫描电子显微镜（SEM）观察注射性藻酸盐印模材料的内部形貌，数字三维测量方法评价印模材料的准确性。结果: SEM结果显示注射型藻酸盐印模材料比Jeltrate藻酸盐印模材料结构致密均匀，气泡含量较少。IA组、JA组、SI组模型与标准模型的差异性（正确度）分别为（49.58±1.453）、（54.75±7.264）、（30.92±1.013）μm。IA组、JA组、SI组内模型之间的差异性（精密度）分别为（85.79±8.191）、（97.65±11.060）、（56.51±4.995）μm。3组印模材料在正确度和精密度上差异有统计学意义（P<0.05）。结论: 新型可注射型的藻酸盐印模材料的准确性优于传统的粉剂型藻酸盐印模材料，但差于加成型硅橡胶印模材料。新型可注射性的藻酸盐印模材料具有良好的操作性能和印模准确性，显示出良好的应用前景。.
Keywords: accuracy; alginate; impression materials; injectability.