Babu, a 7½ years old child, reports with a fracture of
central incisor with an open apex, there is large pulpal
exposure. The treatment of choice is:
The Cvek Pulpotomy on Immature Permanent Teeth
Pulpotomy is an established technique for preserving vital pulp functions in immature teeth that have been subject to pulp-exposing trauma. Inflammation is confined to the surface 2 to 3 mm of the pulp, when it is traumatically exposed and left untreated for up to 168 hours. 
In a classic report, Cvek described a pulpotomy technique in which only the superficial 2 to 3 mm of hyperplastic inflamed tissue was removed with a water-cooled, high-speed diamond bur to place the wound in a healthy site. Hemostasis was then secured before capping with an appropriate material. 
Hemostasis was obtained with saline, and a pulp cap of calcium hydroxide was overlaid with a sealing coronal restoration.
Reference: Cohen Pathways of Pulp 11th ed page no e31