口腔材料学教学中有关铸造包埋材料热膨胀性的理解

受热膨胀是铸造包埋材料的一个重要特性。包埋材料的膨胀可以使容纳金属的铸腔扩大，并以此补偿金属的铸造收缩。在口腔医学专业本科生临床教学中，“蜡型周边的包埋材料受热后，为什么不会向内膨胀侵占失蜡产生的空间？”是学生向授课教师提出最多的一个问题。针对该疑问，我们通过建立简化模型进行计算，结合理论和临床分析，做出了相应的解释，目的是使口腔医学专业学生对包埋材料热膨胀现象获得更加深入的理解。

Analysis on the problems in the thermal expansion of casting investment materials

One important characteristic of casting investment materials is thermal expansion, which can expand the casting cavity and compensate for the shrinkage of metal. The reason why can''t the casting investment materials around the paraffin wax expand inward and occupy the space produced by wax loss after heating is one of the most common questions students ask their teachers in clinical teaching of stomatology undergraduates. To solve this problem, we established a simplified model for calculation, combined with theoretical and clinical analysis, and made corresponding explanations, so that students majoring in stomatology can gain a deeper understanding of the knowledge related to thermal expansion of casting investment materials.