We're discussing whether or not the results of a tummy tuck or an abdominoplasty are permanent. That depends on surgeon who performs the surgery and exactly what was done, in part, and it also depends on how well the patient has taken care of his or her body after the surgery.
So, it's important that the procedure is performed correctly. There are certain techniques that are used in a properly performed surgery: tightening of the muscle wall, removal of an appropriate amount of skin and fat, liposuction in areas that are important to have liposuction. All of these things need to take place in order to have a permanent result.
In addition to that, after having the surgery, it's important for the patient to take care of his or her body. If one were to gain an enormous amount of weight, then, no, the results of the tummy tuck would not be permanent. If a woman were to get pregnant after having a tummy tuck, there's the possibility that all the tissue that was tightened would loosen up, and the results would also not be permanent.
So in answer to the question, "Is a tummy tuck result permanent," it depends on both how well the tummy tuck was performed initially by the surgeon, and the level of care that a patient gives their body after the surgery.