**Question:** In skeletal class III malocclusion will show

A. Protrusion of the maxilla
B. Retrognathia (retrusion of the mandible)
C. Retrognathia (retrusion of the mandible)
D. Retrognathia (retrusion of the mandible)

**Correct Answer:** D. Retrognathia (retrusion of the mandible)

**Core Concept:**

Skeletal class III malocclusion is a dental classification system that describes the relationship between the position of the upper and lower jaws during jaw function. This classification is based on the relationship between teeth and the underlying jaw bones. There are three main types of malocclusion: class I, class II, and class III.

**Why the Correct Answer is Right:**

In skeletal class III malocclusion, the lower jaw (mandible) is positioned more forward than the upper jaw (maxilla). This means that the lower teeth lie behind the upper teeth when the jaws are in a closed position, leading to an increased overbite (the vertical overlap of the upper teeth over the lower teeth). The correct answer, D, refers to retrognathia, which is the condition where the mandible (lower jaw) is retrognathic (or retrognathic mandible).

**Why Each Wrong Option is Incorrect:**

A. Protrusion of the maxilla (option A) is incorrect because this refers to an excessive protrusion of the upper jaw, which would result in an increased overbite. This is different from the situation in skeletal class III malocclusion, where the lower jaw is forward.

B. Retrognathia (option B and C) is incorrect because it refers to the mandible being retrognathic (or retrognathic mandible), which is the opposite of what occurs in skeletal class III malocclusion.

**Clinical Pearl:**

Understanding the different types of malocclusion is essential for dental and orthodontic treatment planning. In skeletal class III malocclusion, retrognathia (or retrognathic mandible) is the key feature that distinguishes it from other malocclusion types. The treatment approach for skeletal class III malocclusion focuses on correcting the mandibular retrognathia by moving the mandible forward, which can be achieved through various orthodontic treatments (e.g., orthognathic surgery or orthodontic treatment), aiming to improve the patient's overall facial appearance and oral function.