Class III malocclusion is associated with which condition?

Class III malocclusion is associated with which condition?

• A. Acromegaly
• B. Achondroplasia
• C. Cleft lip and palate
• D. Down syndrome

Answer: (B)

Class III malocclusion describes a bite where the lower teeth or jaw sit ahead of the upper teeth, often from a relatively underdeveloped upper jaw (midface hypoplasia) or an overgrown lower jaw. Achondroplasia commonly causes midface hypoplasia, so the maxilla doesn’t develop enough to meet the upper teeth, making the lower arch appear protrusive and producing the Class III pattern. This strong association with midface deficiency is why achondroplasia is the best fit. Other conditions can affect facial structure and teeth, but they don’t characteristically produce the same midface deficiency pattern that leads to this occlusal relationship.

Class III malocclusion describes a bite where the lower teeth or jaw sit ahead of the upper teeth, often from a relatively underdeveloped upper jaw (midface hypoplasia) or an overgrown lower jaw. Achondroplasia commonly causes midface hypoplasia, so the maxilla doesn’t develop enough to meet the upper teeth, making the lower arch appear protrusive and producing the Class III pattern. This strong association with midface deficiency is why achondroplasia is the best fit. Other conditions can affect facial structure and teeth, but they don’t characteristically produce the same midface deficiency pattern that leads to this occlusal relationship.