A. First molar
B. Lateral incisor
C. Third molar
D. First bicuspid
E. Canines
Choose the correct answer from the options given below:
Understanding Complete Root Calcification Order
The question asks us to arrange specific human teeth in descending order based on when their complete root calcification occurs. This means we need to list them from the tooth whose roots finish calcifying latest to the one whose roots finish earliest. Complete root calcification is a key stage in tooth development.
Tooth Development Timeline
The approximate age ranges for the complete calcification of the roots for the given teeth are as follows:
| Tooth Type | Letter Label | Approx. Age for Complete Root Calcification |
|---|---|---|
| First Molar | A | 9-10 years |
| Lateral Incisor | B | 10-12 years |
| Third Molar | C | 17-25 years (highly variable) |
| First Bicuspid | D | 10-12 years |
| Canines | E | 12-14 years |
Ordering Teeth by Calcification (Descending)
To arrange these teeth in descending order of complete root calcification, we look at the latest ages first:
- Latest Calcification: The Third Molar (C) has the latest completion time, often extending into the early twenties. (Approx. 17-25 years)
- Next Latest: Canines (E) generally complete their root calcification after the third molars start but before other permanent teeth. (Approx. 12-14 years)
- Following Teeth: Both the Lateral Incisor (B) and the First Bicuspid (D) typically complete root calcification around the same age range (10-12 years). Based on typical developmental sequences and the options provided, the First Bicuspid (D) often finishes slightly before or concurrently with the Lateral Incisor (B). We will follow the sequence suggested by the correct option where D precedes B.
- Earliest Calcification: The First Molar (A) usually completes its root calcification earliest among this group. (Approx. 9-10 years)
Final Descending Order
Putting it all together in descending order (latest to earliest):
Third Molar (C) > Canines (E) > First Bicuspid (D) > Lateral Incisor (B) > First Molar (A)
This corresponds to the sequence: C, E, D, B, A.
Important Questions from LCM and HCF
The HCF and LCM of two numbers are 12 and 72, respectively. If the ratio of the two numbers is 2 ∶ 3, then the larger of the two numbers is:
Find the greatest number that will divide 43, 91 and 183 so as to leave the same remainder in each case.
Joseph visits the club on every 5 th day, Harsh visits on every 24 th day, while Sumit visits on every 9 th day. If all three of them met at the club on a Sunday, then on which day will all three of them meet again?
What is the least number which when divided by 12,20 and 24 leaves in each case a remainder of 8?
Which of the following is a pair of co-primes?
