Teeth which appear twice in life time are called_____

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the type of teeth that appear twice in a person's lifetime.

2. **Identifying the Types of Teeth**: In human dentition, there are two main categories of teeth based on how many times they appear in a lifetime:
- **Monophyodont**: Teeth that appear only once in a lifetime.
- **Diphyodont**: Teeth that appear twice in a lifetime.

3. **Counting the Teeth**: In the human mouth, there are typically 20 primary teeth (also known as baby teeth or deciduous teeth) that will eventually be replaced by permanent teeth. These include:
- 2 incisors
- 1 canine
- 2 molars
- This pattern is mirrored on both sides of the jaw, leading to a total of 20 teeth.

4. **Conclusion**: The teeth that appear twice in a lifetime are referred to as **Diphyodont**.

5. **Final Answer**: Therefore, the answer to the question is **Diphyodont**.

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