Prof. Rooban Thavarajah's Lecture Series - Morphology of Human Deciduous Mandibular Central Incisor Tooth for First BDS students

1. Prof. Rooban Thavarajah
Tooth Morphology
Lecture Series
Dr. Rooban Thavarajah

2. Dr. Rooban Thavarajah
Deciduous Dentition
Mandibular Central Incisor

3. BACK GROUND
 Similar to deciduous mandibular lateral incisor
 Is symmetrical from any surface
 Crown is relatively wider MD than in permanent
incisors – MD dimension NOT greater than
crown length
Dr. Rooban Thavarajah

4. LABIAL ASPECT
 ~ permanent lateral incisor
 root twice length of crown
 Mamelons can be present,
 Appears wide in comparison to its permanent
successor
 Root twice length of crown
Dr. Rooban Thavarajah

5. LABIAL ASPECT
 Proximal outlines are evenly convex - sharp
mesioincisal and distoincisal angles
 Convexity less than Maxillary counterpart
 height of contour - @ contact area in Incisal 3RD
 Incisal margin is straight
 Labial surface - smooth, lacking developmental
depressions, and flatter than labial surface
Dr. Rooban Thavarajah

6. PALATAL ASPECT
 Cingulum is well defined
 Marginal ridges are not so well developed
 Lingual fossa - shallow.
 Smooth
 @ middle, incisal third – flat surface
 Lingual fossa
 MD @ Labial surface > Lingual surface
Dr. Rooban Thavarajah

7. PROXIMAL ASPECT
 Mesial aspect
 Greater LP than permanent incisors.
 Incisal edge is located over root center
 Cervical line contour is evenly curved to Ins. edge
 Distal aspect - similar to mesial BUT -
cervical line exhibits less depth of curvature.
 Distal surface a developmental depression
Dr. Rooban Thavarajah

8. INCISAL ASPECT
 Incisal edge is straight – divides - labial
and palatal portions of the crown into
equal halves.
 MD and LP dimensions are nearly equal
– maxillary central incisor it is wider MD
 Labial convex, Lingual concave
Dr. Rooban Thavarajah

9. ROOT
 Single, relatively long, and slender.
 Labial and Palatal surfaces are convex
 Mesial and distal surfaces are somewhat
flattened.
Dr. Rooban Thavarajah

10. Dr. Rooban Thavarajah

11. Dr. Rooban Thavarajah