Abstract: Cracked tooth is incomplete fracture that originates from the crown and extends to the gingival area. Due to the insidious development，uncontrollable progression，and uncertain long-term prognosis，it often brings challenges to diagnosis，treatment，and prognostic evaluation. This article analyzes the development process of cracked tooth from a biomechanical perspective and the infection characteristics of cracked tooth from a microbiological perspective，aiming to provide new insights for clinical diagnosis and treatment. 

Key words: cracked tooth, crack extension, biomechanics

摘要： 牙隐裂是从牙冠开始并延伸到龈下的不完全折裂，因发展过程隐匿、不可控及远期预后不确定，常给诊断、治疗、预后评估带来挑战。文章通过生物力学视角解析牙隐裂的发展过程，以及微生物学视角解析牙隐裂的感染特点，以期为临床诊疗提供新思路。

关键词: 牙隐裂, 裂纹扩展, 生物力学