Chronology and sequence of primary dentition eruption and various stages of it.

2. DEPARTMENT OF PEDODONTICS
AND PREVENTIVE DENTISTRY
CHRONOLOGY OF
HUMAN DENTITION
By :
Mayank Khandelwal

3. CONTENTS :
1. WHAT IS CHRONOLOGY?
2. SIGNIFICANCE OF CHRONOLOGY
3. PHASES OF DENTITION
4. TOOTH DEVELOPMENT
5. NOLLA’S STAGES OF DEVELOPMENT
6. STAGES OF ERUPTION
7. PRIMARY DENTITION
8. CHRONOLOGY OF PRIMARY DENTITION
9. REFERENCES

4. WHAT IS CHRONOLOGY ?
CHRONOS : TIME
LOGOS : STUDY
IT IS THE STUDY WHICH DEALS WITH THE TIMINGS OF
VARIOUS STAGES OF TOOTH DEVELOPMENT, STARTING
WITH INITIATION OF THE FIRST DENTAL TISSUE
LAID DOWN TO THE EMERGENCE OF TOOTH IN THE
ORAL CAVITY AND ITS COMPLETION OF
CALCIFICATION.

5. SIGNIFICANCE OF CHRONOLOGY
o To avoid treatment that can damage developing
permanent teeth
o To assess unknown age of the patient
o To assess the growth of the patient

6. PHASES OF DENTITION
PRIMARY DENTITION MIXED DENTITION
PERMANENT DENTITION

7. TOOTH DEVELOPMENT

8. NOLLA’S STAGES OF DEVELOPMENT

9. STAGES OF ERUPTION
 Eruption is defined as the movement of developing teeth
through the bone and the underlying mucosa of the jaws
to appear in the oral cavity and reach the occlusal plane.
 It can be divided into 3 phases :
1. Pre-eruptive phase
2. Eruptive phase
3. Functional phase

10. STAGES OF ERUPTION

11. PRIMARY DENTITION

12. PRIMARY DENTITION
 Contains 5 teeth per quadrant (20 in total):
• Central incisors
• Lateral incisors
• Canine
• 1st Molar
• 2nd Molar
Primary teeth start to develop at about 6 weeks intra uterine life
and continues to develop until they erupt in oral cavity with
root taking further more time of about 1 year to completely form.

13. CHRONOLOGY OF PRIMARY DENTITION
 Emergence of primary dentition takes place at about 6-8 months
with mandibular central incisor as the 1st tooth to erupt.
 It takes about 3 years for primary dentition to develop completely
which remains functional till the age of about 11 years after which
they are completely lost.
 Calcification of primary dentition begins at about 13 weeks intra uterine
and by 20 weeks, all teeth start calcifying.

14. CHRONOLOGY OF PRIMARY DENTITION
 Crown formation of primary tooth continues after birth for about :
 3 months : Central Incisor
 4 months : Lateral Incisor
 8-9 months : Canine
 7 months : 1st Molar
 10-11 months : 2nd Molar

15. CHRONOLOGY OF PRIMARY DENTITION
The predominant sequence of eruption of primary
teeth are as follows :
 Central Incisor (A)
 Lateral Incisor (B)
 1st Molar (D)
 Canine (C)
 2nd Molar (E)

17. CHRONOLOGY OF PRIMARY DENTITION

18. EXFOLIATION OF PRIMARY DENTITION

19. REFERENCES
 Textbook of Pedodontics by Shobha Tandon
 Wheeler’s Dental Anatomy, Physiology and
Occlusion by Nelson and Ash
 Internet