Small white spots on teeth can be caused by calcium deficiency, as well as poor enamel development and poor oral hygiene. 1. Calcium deficiency: During the development of teeth, if there is a lack of calcium, it may affect the development of teeth, resulting in small white spots on the top of the teeth. 2. Enamel dysplasia: Enamel dysplasia can also cause white spots on the teeth, i.e. white spots, it is recommended to consult a dentist. 3. Poor oral hygiene: If oral hygiene is poorly maintained, bacteria and food adhere to the surface of the teeth and demineralize the enamel, which can produce small white spots. Teeth with small white spots may also be caused by other reasons, it is recommended to consult a doctor in time, under the guidance of the doctor to clarify the cause, targeted treatment measures.