The condition in which the occlusal plane of the teeth lies nearer the Frankfurt plane than it does in normal occlusion is called
**Core Concept**
Dental occlusion refers to the relationship between the upper and lower teeth, and their position in the jaw. The Frankfurt plane is an anatomical reference line used in dentistry to evaluate the position of the occlusal plane. An abnormal relationship between these two planes can indicate various occlusal disorders.
**Why the Correct Answer is Right**
The condition described is an example of a Class II division 1 occlusal relationship, where the upper teeth are positioned more forward than the lower teeth. This results in the occlusal plane lying closer to the Frankfurt plane than normal. The Frankfurt plane is a horizontal reference line that passes through the upper margin of the external auditory meatus and the lower margin of the orbit. In a normal occlusal relationship, the occlusal plane is positioned more posteriorly, allowing for proper alignment and function of the teeth.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not accurately describe the relationship between the occlusal plane and the Frankfurt plane in the condition being asked about.
**Option B:** This option is incorrect because it is a different occlusal relationship altogether, and does not address the specific condition described in the question.
**Option C:** This option is incorrect because it is a type of occlusal disorder, but it does not specifically describe the relationship between the occlusal plane and the Frankfurt plane.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the Frankfurt plane is used as a reference for evaluating the position of the occlusal plane in dentistry. A deviation from the normal relationship between these two planes can indicate various occlusal disorders, and should be addressed by a dentist or orthodontist to prevent potential complications.
**Correct Answer:** C. Class II division 1 occlusal relationship.