Set Traits

Maxillary Central Incisors

Set Traits are characteristics that differentiate teeth in the primary and secondary dentitions. Traits of the secondary tooth will be listed that are different from their primary counterparts.

The crowns of the secondary maxillary central incisors have a greater crown length (cervicoincisal) than crown width (primary maxillary central incisors are wider mesiodistally compared to their crown length).

The mesial and distal crests of curvature of the secondary maxillary central incisors are at different locations. The mesial crest of curvature is in the incisal third of the crown approaching the mesioincisal corner of the crown and the distal crest of curvature is located at the junction of the middle and incisal third of the crown. The primary central incisors have mesial and distal crests of curvature in the incisal third of the crown with the distal slightly more cervical in its position. They are virtually in the same position mesially and distally.

There is less cervical constriction mesiodistally and labiolingually in all secondary teeth compared to their primary counterparts.

The crown:root ratio is less for all primary teeth compared to their secondary counterparts. Primary teeth have much longer roots in comparison to their crowns compared to secondary teeth.

All of these characteristics apply to both the maxillary central and lateral incisors.

Maxillary Lateral Incisors

The crowns of the permanent maxillary lateral incisors have a greater crown length (cervicoincisal) than crown width as do the deciduous maxillary lateral incisors but the deciduous maxillary lateral incisors differ in proportions and appear to have a shorter, wider crown in comparison.

The mesial and distal crests of curvature of the permanent maxillary lateral incisors are at different locations- mesial at the junction of the middle and incisal third of the crown; distal in the middle third of the crown (deciduous maxillary lateral incisors have mesial and distal crests of curvature in the incisal third of the crown with the distal slightly more cervical in its position).

There is less cervical constriction mesiodistally and labiolingually in all permanent teeth compared to their deciduous counterparts.

The crown:root ratio is less for all deciduous teeth compared to their permanent counterparts (deciduous teeth have much longer roots in comparison to their crowns compared to permanent teeth).