Abnormal dental enamel morphology Enamel agenesis 2021-05-07T10:59:43Z Complete or almost complete absence of enamel. Enamel agenesis can indicate a total absence of enamel or the presence of a very thin enamel layer that is difficult to visualize during clinical examination. It may need microscopic studies to determine whether any enamel is still present. It can be present isolated and as part of rare syndromic entities.