Fracture of #8 planned for extraction

Correct answer: C. Making a definitive restoration while the patient is still in orthodontic treatment

• A. A provisional crown is exactly what is indicated during the interim period, maintaining esthetics, function and space.
• B. An implant is a reasonable definitive plan for a fractured non-restorable central incisor — placed after orthodontic movement is complete and, in a growing patient, after skeletal growth has finished.
• C. Correct — this is the EXCEPTION. Definitive restorations are NOT fabricated while active orthodontic treatment is ongoing. Tooth positions, occlusal relationships and the space available are all still changing, so a definitive restoration made now will not fit the final occlusion. PROVISIONALISE during treatment and definitively restore afterwards.
• D. A definitive crown is appropriate once tooth position and occlusion are stable.

Correct answer: D. Orthodontic treatment (external apical root resorption)

• A. Dens invaginatus is an infolding of enamel and dentin into the crown and root before mineralisation, giving a 'tooth within a tooth' appearance.
• B. Hypercementosis is excessive cementum deposition producing a BULBOUS, ENLARGED root — the opposite of shortening.
• C. Internal resorption originates within the pulp and appears as a balloon-like widening of the canal with a smooth outline — not as a shortened apex.
• D. Correct. EXTERNAL APICAL ROOT RESORPTION is a well-recognised sequela of orthodontic treatment, producing shortened, blunted roots. The MAXILLARY INCISORS are the most commonly affected teeth. Risk rises with prolonged treatment duration, heavy continuous forces, intrusive and torquing movements, and pre-existing blunted or pipette-shaped root form.

Note: This links directly to the Day 1 item about a cervical fracture in a patient with short roots after five years of orthodontics. When you see BLUNTED APICES plus an ortho history, the answer is orthodontic root resorption.