Upper lateral incisor unilateral agenesis is best characterized by which statement?

Upper lateral incisor unilateral agenesis is best characterized by which statement?

• A. Long persistence of the temporary teeth on the arches
• B. Early extraction of temporary teeth is necessary
• C. Mesial movement of teeth is possible at any age
• D. Extraction of the opposite lateral incisor is not obligatory

Answer: (A)

Unilateral upper lateral incisor agenesis means the permanent upper lateral incisor on one side never develops. When a permanent tooth is missing, the corresponding primary tooth often remains in place longer because there’s no eruption of a successor to trigger resorption of its root and exfoliation. That’s why long persistence of the temporary teeth on the arches is the typical finding in this situation. Other statements aren’t defining features: there isn’t a universal rule that deciduous teeth must be extracted early, and mesial movement of teeth or extraction of the opposite lateral incisor isn’t obligatory in every case; those outcomes depend on individual space, growth, and treatment goals.

Unilateral upper lateral incisor agenesis means the permanent upper lateral incisor on one side never develops. When a permanent tooth is missing, the corresponding primary tooth often remains in place longer because there’s no eruption of a successor to trigger resorption of its root and exfoliation. That’s why long persistence of the temporary teeth on the arches is the typical finding in this situation. Other statements aren’t defining features: there isn’t a universal rule that deciduous teeth must be extracted early, and mesial movement of teeth or extraction of the opposite lateral incisor isn’t obligatory in every case; those outcomes depend on individual space, growth, and treatment goals.