Which of the following can be predicted from a flush terminal plane of primary dentition?
**Core Concept**
The flush terminal plane of primary dentition refers to the characteristic alignment of the primary teeth at the level of the occlusal plane, where the incisal edges of the upper and lower central incisors are at the same level. This alignment is often seen in children with a Class I malocclusion.
**Why the Correct Answer is Right**
A flush terminal plane can be predicted from a primary dentition with a Class I malocclusion, where the molar relationship is normal and the primary teeth are aligned in a straight line. This is because the primary teeth are smaller and more widely spaced than the permanent teeth, and the occlusal plane is not yet developed. The presence of a flush terminal plane suggests that the primary teeth are in a normal alignment, and the permanent teeth are likely to erupt in a similar alignment.
**Why Each Wrong Option is Incorrect**
* **Option A:** A Class II division 1 malocclusion is characterized by a retroclined upper central incisor, which would not result in a flush terminal plane.
* **Option B:** A Class III malocclusion is characterized by a protruded lower central incisor, which would not result in a flush terminal plane.
* **Option C:** A Class II division 2 malocclusion is characterized by a retroclined upper central incisor and an overjet, which would not result in a flush terminal plane.
**Clinical Pearl / High-Yield Fact**
A flush terminal plane of primary dentition can be a useful indicator of a Class I malocclusion, which has a good prognosis for orthodontic treatment.
**Correct Answer:** C.