Loose teeth are mostly caused by inflammation and other reasons, and have no direct causal relationship with kidney deficiency. From the perspective of Chinese medicine, kidney deficiency can trigger loose teeth or even loss, but it will not only produce this one isolated symptom, but also other physical discomfort. From the perspective of dentistry, loose teeth indicate a decrease in the alveolar bone and supporting tissues around the teeth, just like the soil around a tree loosening, leading to root instability. Periodontitis is the most common cause of loose teeth, and if left untreated, it can lead to unsaved teeth. Additionally, inflammation of the root tip can also cause loose teeth, requiring treatment such as a root canal. Trauma and bite problems, likewise, can cause loose teeth. When teeth are in a healthy state, there is a certain degree of mobility in the horizontal direction, but it is usually less than 0.02mm and is not easy to be noticed. Therefore, when a tooth loosens to a detectable level, you should visit your dentist as soon as possible.