Dental formula of adolescent human being before seventeen year-

Options

A. `(2122)/(2122)`
B. `(2123)/(2123)`
C. `(2102)/(2102)`
D. `(2023)/(1023)`

Answer

To determine the dental formula of an adolescent human being before the age of seventeen, we need to understand the types of teeth present and their arrangement in the mouth. Here is the step-by-step solution:

### Step 1: Understand the Types of Teeth
Humans have different types of teeth: incisors, canines, premolars, and molars. Each type has a specific function:
- **Incisors**: Used for cutting food.
- **Canines**: Used for tearing food.
- **Premolars**: Used for crushing and grinding food.
- **Molars**: Also used for grinding food.

### Step 2: Identify the Dental Formula for Adults
The dental formula for an adult human is typically represented as:
- **2-1-2-3** (for each quadrant of the mouth)
This means:
- 2 Incisors
- 1 Canine
- 2 Premolars
- 3 Molars

Thus, for the entire mouth, it is:
- **2-1-2-3 by 2-1-2-3** (for the upper and lower jaws).

### Step 3: Determine the Dental Formula for Adolescents
For adolescents under the age of seventeen, the third molars (wisdom teeth) have not yet erupted. The first molar appears around age 6, and the second molar appears around age 12. The third molar typically erupts after age 17.

### Step 4: Write the Dental Formula for Adolescents
Since the third molars are not included, the dental formula for an adolescent human being before seventeen years would be:
- **2-1-2-2 by 2-1-2-2**
This indicates:
- 2 Incisors
- 1 Canine
- 2 Premolars
- 2 Molars (first and second molars)

### Step 5: Conclusion
Thus, the dental formula of an adolescent human being before the age of seventeen is:
- **2-1-2-2 by 2-1-2-2**.