Dens invaginatus: review, relevance, and report of 3 cases.

Dens invaginatus is a rare developmental morphoanatomical variation resulting from the infolding of the dental papilla before biological mineralization that allows the invagination of inner dental epithelium. Permanent maxillary lateral incisors are most commonly affected, and the condition is frequently bilateral, but it may also prevail in permanent maxillary central incisors. The purpose of this paper was to provide an overview of the etiopathogenesis, frequency of occurrence, and clinical and radiographic features and to discuss 3 dens invaginatus cases.