Successful apexogenesis achieves all of the following EXCEPT:

Correct answer: A. Revascularisation of a necrotic pulp

• A. CORRECT — this is the exception. APEXOGENESIS is a VITAL pulp therapy. It presupposes a living radicular pulp with an intact apical papilla, which is preserved so that normal development continues. Revascularisation (regenerative endodontics) is an entirely different procedure performed on a NECROTIC immature tooth, in which the canal is disinfected and a blood clot or scaffold is induced to allow ingrowth of stem cells.
• B. Dentinal wall thickening is one of the principal benefits, since surviving odontoblasts keep laying down dentine and strengthen a thin, fracture-prone root.
• C. Apical closure occurs physiologically as root development completes.
• D. Root lengthening does occur — Hertwig epithelial root sheath continues to function while the pulp remains vital.

Note: Apexogenesis: vital pulp, root keeps growing. Apexification: necrotic pulp, induce an apical barrier only — the root does NOT lengthen or thicken. Revascularisation: necrotic pulp, attempt to restore development.