Under normal circumstances, the tooth roots develop 1/2~3/4 of the tooth crowns begin to erupt, and the teeth that have passed the eruption period and still fail to erupt in the jawbone tissue are called ambiguous teeth. The buried tooth can occur in all stages of the tooth. The causes of ambulant blockage: including local and systemic factors. There are many local factors: e.g., `premature extraction of the baby tooth due to trauma or severe caries, and lack of space due to displacement of the tooth next to the gap; cyst caused by apical infection of the baby tooth; the baby tooth is not lost in time; the presence of multiple teeth, dental tumors or other types of jaw bone cysts or tumors blocking the eruption of permanent teeth; abnormal position of the permanent tooth germ, such as lateral or inverted growth; malformation of the permanent tooth germ itself, etc. Systemic factors: malnutrition, rickets, endocrine disorders (hypothyroidism, parathyroidism, hypopituitarism), hereditary syndromes, etc. Problems that may arise from untimely treatment of ambulant teeth: displacement or tilting of adjacent teeth labially or palatally; loss of arch length; compression of adjacent roots with root resorption; formation of tooth-containing cysts with compression of jawbone resorption; overgrowth of opposing teeth with disturbed bite and jaw relationship; causing occlusal trauma, etc. When teeth are found to be delayed to erupt, it is necessary to seek medical examination as early as possible to find out the problem and treat it timely, especially to eliminate the local causes as early as possible. 1, multiple teeth: after early extraction, some of the ambiguous teeth can erupt. 2.Infection causing tooth-containing cysts: some of the ambulant teeth can erupt after surgery. 3.Insufficient eruption gap: orthodontic development gap, usually can erupt. 4.Tooth tumor: Remove it in time, orthodontic traction is needed during the period of tooth replacement and permanent teeth. 5.Embedded teeth whose root tip has been developed or permanent tooth germ position is abnormal need to be treated by orthodontic traction.