Anatomy Of The Maxillary Central Incisor
The crown of the maxillary central incisor is the longest of all the human teeth, including that of the canines. The crown is narrowest in the cervical third and becomes broader toward the incisal third.
The broad depression (concavity) on the lingual surface of the maxillary central incisor is called lingual fossa - fossa lingualis, positioned immediately incisal to the cingulum. The cingulum is- an enlargement on the cervical third of the lingual surface of the crown on anterior teeth. The lingual fossa is bounded by the mesial and distal
marginal ridges. Due to the slightly distal placement of the cingulum, the mesial marginal ridge is longer than the distal marginal ridge.
From the incisal aspect the crown has a triangular shape, with a slightly curved labial outline. The incisal ridge is the widest part of the crown. The labial outline of the crown is broadly convex, with a mesial and distal depression on the labial surface, located in the middle and incisal thirds.