A child has 12 permanent and 12 deciduous teeth, what could be his age:
**Core Concept**
The development and eruption of teeth in children follow a predictable pattern, allowing for estimation of age based on dental status. The presence of permanent and deciduous teeth is a key indicator of dental maturity.
**Why the Correct Answer is Right**
Typically, by the age of 12 years, most children have a mix of primary (deciduous) and permanent teeth. The presence of 12 permanent and 12 deciduous teeth suggests that the child is at a stage where the primary teeth are being gradually replaced by permanent teeth. This process usually starts around the age of 6 years and continues until the age of 12-14 years. The correct answer reflects this typical timeline for dental development.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it is too young for a child to have 12 permanent and 12 deciduous teeth, as the process of tooth replacement starts around the age of 6 years.
**Option B:** This option is incorrect because it is too old for a child to have 12 deciduous teeth, as most children have a majority of permanent teeth by this age.
**Option C:** This option is incorrect because it is too old for a child to have 12 deciduous teeth, and it does not take into account the typical timeline for dental development.
**Clinical Pearl / High-Yield Fact**
Keep in mind that dental development can vary among children, and some may have more or fewer permanent teeth at a given age. However, a general rule of thumb is that by the age of 12 years, most children have a mix of primary and permanent teeth.
**Correct Answer:** D. 12 years.