A panoramic radiograph of a 9-year-old patient shows a radiolucent structure between teeth #8 and #9 (upper central incisors). What is the most likely diagnosis?

Correct answer: C. Mesiodens (supernumerary tooth between the centrals)

• A. A lateral periodontal cyst occurs lateral to the root of a vital tooth — classically between mandibular premolars. It is unlikely between maxillary central incisors of a child.
• B. A median diastema is an ABSENCE of bone/tooth — it would not present as a distinct radiolucent structure with internal density. Diastemas are space between teeth, not distinct lesions.
• C. CORRECT. A mesiodens is the most common supernumerary tooth, occurring in the premaxilla between the maxillary central incisors. On radiograph, it appears as a small, often cone-shaped radiopaque structure within a radiolucent follicular sac. In a 9-year-old, a radiolucency between #8 and #9 with a tooth-like density inside is classic for an unerupted mesiodens.
• D. A periapical cyst from tooth #8 would appear at the ROOT APEX, not between the two central incisors at the crown level. In a 9-year-old, the teeth are likely vital.