Following eruption, how long does a tooth root take to complete its development?

Correct answer: A. 2-3 years

• A. Correct. After a tooth erupts into the oral cavity, root development takes approximately 2-3 more years to complete (apex closure). For example, a maxillary central incisor erupts around age 7-8 and its root is complete around age 10.
• B. Root completion does not occur at eruption — teeth erupt before roots are complete (apexogenesis still needed).
• C. 5-7 years after eruption is too long — root formation is typically complete in 2-3 years.
• D. 6-12 months is too short for root completion after eruption.