Scientists say it is too early to see whether the revolutionary operation in August was a success, but the surgery paves the way for other body parts to be grown to order, according to the University of Massachusetts' Medical Centre.
Raul Murcia's thumb was crushed in an accident earlier this year but the mangled remains were kept alive by sewing them on to his chest to keep the skin alive.
Dr Charles Vacanti, a tissue-engineering specialist, then built a "scaffold" out of coral in the shape of the thumb bone. Bone-producing cells were taken from Mr Murcia's forearm and grown in a test-tube for eight weeks until there were enough to transplant.
The coral thumb was then attached to Mr Murcia's hand and bone cells were injected into the porous material. The scientists believe that they will eventually form proper bone and the coral scaffold will dissolve. Flesh grown from the original thumb saved in the accident was used to cover the new bone.
Mr Murcia's thumb remains swollen from the operation. But it is hoped the procedure will have proved successful.
Similar tissue culture and transplant technique will allow a range of new surgical procedures in future. Tissue engineering could help grow new breasts for women who have had mastectomies and scaffolds implanted into defective organs, such as hearts and livers, could allow the regeneration of those organs.
Dr Vacanti has been at the forefront of the developments. He was responsible for the striking image three years ago of a laboratory mouse apparently sprouting a human ear.