The baby nine months has not yet teeth can choose to observe, supplemental nutrition, check the status of bone function, etc., we recommend patience, if necessary, go to the hospital to find out the cause of timely treatment. The fact that the baby has not yet grown teeth at nine months may be a sign of late eruption of teeth, which may be due to genetic, nutritional deficiencies, bone function abnormalities and other reasons. Genetic factors of the late eruption, you can patiently wait for the teeth to erupt, generally can be observed until about one year old, not yet teeth can be photographed to confirm the condition of the embryo. Nutritional deficiencies can be supplemented with vitamins and various elements needed for growth and development, such as calcium, zinc, iron and so on. Bone function abnormalities caused by rickets can be supplemented with vitamin D and calcium. It is recommended to consult the doctor in time to clarify the reasons for the non-eruption of baby teeth, and carry out targeted treatment in time.