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
Six bells begin to toll together and toll, respectively, at intervals of 3, 4, 6, 7, 8 and 12 seconds. After how many seconds, will they toll together again?
A and B are two prime numbers such that A > B and their LCM is 209. The value of A 2 - B is:
Find the least number which when divided by 12, 18, 24 and 30 leaves 4 as remainder in each case, but when divided by 7 leaves no remainder.
Calculate the HCF of \(\frac{12}{5}\) , \(\frac{14}{15}\) and \(\frac{16}{17}\) .
Three numbers are in the proportion of 3 : 8 : 15 and their LCM is 8280. What is their HCF?
