Maxillary

Mandibular

Contact

Distal: At junct incisal & mid 1/3^rd.

Distal: incisal 3^rd, cervical to mesial contact.

Crown

2mm narrower & less symmetrical than central. "oblong".

Tilted distally-"bent appearance". Make distal outline shorter than mesial.

Incisal Angles

Both more rounded than central. Mesioincisal more acute & distoincisal more obtuse central.

*Distoincisal is noticeably more rounded than mesial.

Proportions

Root longer than crown. Can be longer than max central. Root:crown > max central.

Root shape

Blunt from proximal.

Narrow lingually compared to facial.

Lingual fossae

More pronounced and covers less area than max central. Deep or shallow.

Not pronounced.

Cingulum

Centered, narrower & more convex than max central.

Slightly distal.

Marginal ridges

Distal: shorter than mesial due to incisal ridge sloping distally. Curves.

Mesial is longer than distal due to placement of the cingulum. Overall, not pronounced.

Pits

Present. Often must be restored due to decay.

Overall Lingual anatomy

Fewer than central.

Accessory lingual ridges

May possess near cingulum

Root depression

On mesial, where mesial is flattest side. Can be on distal. Both on mid root.

Both mesial and distal. More distinct on distal.

Incisal Edge

1.0 to 1.5 mm & straighter than max central. Slope cervically toward distal & lingual.

On or lgual to the long axis of root. Viewing form mesial, edge *twists distolingually which places it more lingual to LAR.

CEJ

More curvature on mesial than distal.

Distal: curves 1.4 mm incisally.

Height of contour

Lingual: cervical 3^rd.

Crown width

M.D. wider than F.L. However sometimes they can be equal.

Wider F.L. than M.D. No symmetry to to distolingual twist.

Crown outline

Resembles central but narrower M.D. Labial more convex than max central.

Labial outline convex in incisal 3^rd.

Labial depressions

Less prominent than central.

Minimal. Smoothe like central.

Root Curvature

Distally in apical 1/3^rd.

May have distal bend.