Mandibular Incisors Permanent

Question 1

T/F the central incisor has the smallest mesiodistal dimensions of any tooth?

Answer 1

T

Question 2

Is the central smaller or large than the lateral?

Answer 2

smaller, which is opposite the maxillary

Question 3

Where are the contact areas and what way is the labial surface inclined?

Answer 3

The contact areas are near the incisal ridges

There is a lingual incline of the tooth

Question 4

General characteristics of the mandibular central

Answer 4

• Smallest tooth,
• Crown has slightly more than half mesiodistal diameter of max central,
• labiolingual is 1mm less than maxillary central, root is narrow MD and wide LL,
• length of root is as great if not longer than max. central.

Question 5

Labial view details on mand. central (5)

Answer 5

• Incisal ridge is straight, at right angles to long axis of root
• Mesial and Distal outlines drop straight to contact areas and taper evenly to cervix
• Mesial and Distal outlines of root are fairly straight to apical area, slight curve to distal
• labial face is smooth, with flattened surface at incisal third, middle third is convex
• Face at cervix is more convex along with the root.

Question 6

Lingual view details on mand. central (5)

Answer 6

• Lingual surface is smooth, slight concavity at incisal third
• Marginal ridges are almost absent, sometimes prominent near incisal
• Surface is flat progressing to convexity at cervical third
• shows least developmental grooves along with lateral
• Outlines are symmetrical

Question 7

Mesial View details on mand. central (11)

Answer 7

• Labial face is straight above cervical curvature
• Lingual outline is straight w/labial inclination above cingulum
• concave at middle third (lingual)
• Incisal ridge round or worn flat and lingual to center of root
• Cervical line curvature towards incisal almost one third the length of root
• Root outline is straight form cervix through middle third
• apex may be blunt of pointed
• Mesial surface is convex, smooth at incisal third, tending to concavity at cervix
• Mesial surface of root is flat below cervical line
• usually have broad developmental depressions along most of root
• root depressions usually deeper at middle to apical thirds

Question 8

Distal View on mand. central (3)

Answer 8

• Cervical line curvature is about 1 mm less than mesial
• Distal surface of crown and root similar to mesial
• Developmental depression on distal may be more marked with groove at center

Question 9

Incisal view on mand. central (5)

Answer 9

• bilateral symmetry
• mesial half almost identical to distal half
• incisal edge is almost at right angle with labiolingual bisecting line
• LL dimension is always greater than MD
• Crown tapers to lingual

Question 10

Pulp chamber anatomy mand. central (3)

Answer 10

• LL section: pulp horn is well developed, large pulp chamber, tapering to apex
• MD section: narrow cavity w/ usually only one pulp horn, tapers to apex
• Root section is often ribbon like, sometimes two canals may be present

Question 11

Mesial and Distal view mand. lateral (5)

Answer 11

• mesial side of the crown is usually longer than distal
• incisal ridge slopes distally
• Distal contact is more in a cervical direction
• the root is usually considerably longer
• Will have developmental depressions mesially and distally

Question 12

Incisal view on mand. lateral

Answer 12

• ridge is not at right angles to bisecting line
• Ridge or edge is curved to follow the curvature of arch
• Curvature gives the appearance of crown being twisted on root.

Question 13

Pulp chamber of mand. lateral

Answer 13

very similar to central incisor