MANDIBULAR LATERAL INCISOR

• CHRONOLOGYDental organ appearance 5MIU

Start of calcification 3-4 M

Enamel completed 4-5Y

Eruption 7-8Y

Root completed 10Y

• Mandibular lateral incisor resembles central incisor except that its slightly larger by 0.5 mm in all aspects.

• structure

FEATURESLABIAL ASPECT• The mesial side is longer than the distal side • Incisal margin slopes slightly towards the distal

surface• The disto-incisal angle is more rounded than the

sharp mesio-incisal angle• The distal contact is more cervically located than

the mesial one since it is in contact with the canine

cont.……

• The crown is large than of central and root is longer by about 1.5mm

• The distal contact area at the junction of the incisal and middle thirds is the only mandibular incisor contact point which is not in the incisal third

• INCISAL ASPECT• The incisal edge is not straight mesio-distally

as in the central incisor rather it curves lingualy in its distal portion to follow line of the dental arch-it has to fit into maxillary arch

• The cingulum is shifted distally and the incisal ridge follows the curvature of the dental arch

MESIAL AND DISTAL ASPECTS• Differ from the central incisor in;• Distal surface of the lateral incisor is shorter

than the mesial surface• Both cervical line curvatures are slightly less

than that of the central incisor• Distal contact area is more cervically located

than the mesial one• Root depressions are seen on both surfaces

DIFFERENCES BETWEEN MANDIBULAR CENTRAL AND LATERAL INCISORS

Central incisor is smaller than lateralDisto-incisal angle of the central incisor is sharp and

at right angle while of lateral incisor is roundedMandibular central central incisor is bilateral, lateral

incisor is asymmetry

• DIFFERENCES BETWEEN MANDIBULAR AND MAXILLARY INCISORS

• Maxillary incisors are larger in size• Crown of maxillary incisors have a foramen

caecum on the palatal surface• Maxillary incisors have prominent marginal

ridges and cingulum• The lingual and palatal fossa is deeper in

maxillary incisors

Cont.…….

• Mamelons on buccal surface of maxillary incisor differ in size while those of mandibular incisors are equal

• Root of maxillary incisors are triangular in cross-section (at the cervical level) while those of mandibular incisors are oval.

• Maxillary central

• Maxillary lateral incisor

• Mandibular lateral incisor

• Mandibular central