Cells in the human body are constantly metabolized and updated. After replacement, all the previous cells died and were replaced by new cells. So, of course it will be the anterior cruciate ligament.
In fact, you don't need to worry, because you are doing autologous tendon reconstruction. In other words, the anterior cruciate ligament is replaced by your own semitendinosus tendon.
Anterior cruciate ligament and semitendinosus tendon have the same tissue structure and cell type, and they are all their own cells. The difference between them is that they have different functions in the body. So after the replacement, it just moved one position. Ever heard of skin transplantation? If you burn your hand or arm, it won't matter after a while (where can you ask the skin? ); The difference is that tendons adapt slowly.
In the first half of tendon replacement, the blood supply of tendon muscle mainly depends on the blood vessels of muscle, and the blood supply of muscle is relatively rich (for example, it is equivalent to the children of rich families who have been overnourished since childhood). The anterior cruciate ligament is mainly supplied by synovial fluid, and the supply of bone stops also accounts for a part; Joint fluid and bone anchor point provide relatively little nutrition for anterior cruciate ligament (for example, it is equivalent to a poor child who grew up malnourished and grew up on simple food).
Moreover, semitendinosus muscle replacement is a simple boneless tendon replacement (allogenic tendon is a "bone-tendon-bone" model). After replacement, we should rely entirely on joint synovial fluid for nutrition. Therefore, the semitendinosus muscle after replacement should adapt to the "living environment" in the knee joint.
Finally, to sum up, the ligament after replacement will completely become the anterior cruciate ligament in about 3 months. Don't do strenuous exercise for three months. Because it takes time for semitendinosus muscle to replace tendon and calcaneus.
Finally, you are still young, and it is not bad to do autologous semitendinosus replacement. Allogeneic "bone-tendon-bone" replacement has rejection and so on. Don't ask the doctor why he didn't do this for you.