Mandibular Lateral Incisors

Question 1

For mandibular lateral incisors, what is the expected age of eruption?

Answer 1

7-8 years

Question 2

For mandibular lateral incisors, what is the crown shape from the facial/lingual views?

Answer 2

Trapezoid

Question 3

For mandibular lateral incisors, from the facial/lingual view how do the mesial and distal outlines compare?

Answer 3

The mesial outline is only very slightly convex with a sharp MI angle while the distal outline is slightly convex with a rounded DI angle. MD incisal edge slants toward the distal.

Question 4

For mandibular lateral incisors, what are the heights of contour (occlusogingival contact points) for the mesial and distal sides?

Answer 4

Mesial: Incisal 1/3
Distal: Incisal 1/3 BUT more cervical than mesial contact point

Question 5

For mandibular lateral incisors, how prominent are the lingual fossa structures?

Answer 5

Not very. lingual fossa is barely visible, convex cingulum is less pronounced, and the mesial and distal marginal ridges are less pronounced. Tooth still narrows lingually from incisal view, however.

Question 6

Are mandibular lateral incisors smaller or laarger than mandibular central incisors?

Answer 6

Larger

Question 7

Do mandibular lateral or central incisors have longer roots?

Answer 7

Lateral

Question 8

Describe the mandibular lateral incisor root shape, apex, bends, and cross section shape.

Answer 8

Mandibular lateral incisor roots are narrow, conical in shape, taper to a point at the apex and dilacerate to the distal. in cross section they appear triangular (similar to maxillary incisors, not mandibular central incisors which are oval in cross section).

Question 9

How many mandibular lateral incisor roots are there per tooth? Pulp chamber shape in cross section?

Answer 9

Generally 1 root. 2 roots 40-45% of the time.
The pulp chamber appears oval in cross section (same as mandibular central incisor root, different than maxillary incisors which are triangular).

Question 10

For mandibular lateral incisors, what is the crown shape from the mesial/buccal view?

Answer 10

Wedge

Question 11

For mandibular lateral incisors, how do the facial and lingual outlines compare from the mesial/distal view?

Answer 11

The lingual outline is convex in the cervical 1/3 and concave in the middle and incisal 1/3s.
The facial outline is convex in the cervical 1/3 and flat in the middle and incisal 1/3s (flat but slopes lingually)

Question 12

For mandibular lateral incisors, what are the buccal and lingual heights of contour?

Answer 12

Cervical 1/3 for both facial and lingual sides

Question 13

For mandibular lateral incisors, what is unique about the cingulum?

Answer 13

It is offset to the distal side of the tooth and less developed

Question 14

For mandibular lateral incisors, besides sloping cervically the incisal edge of the DI corner slants in what direction causing the crown to appear ‘twisted’ on the root from the incisal view?

Answer 14

Lingually

Question 15

For mandibular lateral incisors, what is the crown shape from the incisal view?

Answer 15

triangular or diamond shaped.

Question 16

For mandibular lateral incisors, what is the facial and lingual outline from the incisal view?

Answer 16

Both lingual and facial sides appear convex, rounded. Why tooth referred to as diamond shaped from incisal view.

Question 17

For mandibular lateral incisors, number of lobes?

Answer 17

4 lobes. 3 facial 1 lingual

Question 18

For mandibular central and lateral incisors, where are facets worn on teeth throughout life?

Answer 18

Facets are worn on facial surface in the incisal 1/3 due to contact with maxillary incisors.