Enamel hypoplasia
Enamel hypoplasia is a defect of the teeth in which the enamel is hard but thin and deficient in amount, caused by defective enamel matrix formation with a deficiency of vitamin D in the body. Usually the condition involves part of the tooth having a pit in it. In some cases, the natural enamel crown has a hole in it, and in extreme cases, the tooth has no enamel, which doesn't mean the tooth doesn't exist because dentin is also a component of teeth.