The Influence of Porcelain Fused to Metal Crowns with Different Crown Margins on the Periodontal Tissues of the Teeth with Chronic Adult Periodontitis; Variation Analysis on Anatomical Properties and Chemical Compositions between Chinese White Poplar and Burl 不同冠边缘位置的金瓷冠对慢性牙周炎基牙牙周组织的影响毛白杨与瘿瘤解剖特性和化学组成变异分析
Thebasic reasons of low crown and resistance to cold have been revealed through anatomical analyses. 同时从叶和根解剖结构上的变化,查明了枳高砧抗寒能力增强和树冠矮化的基本原因。