I will say that 90% of all abdominoplasties also include liposuction of the lateral flanks. It will enhance the natural curves improving the results without the boxy look.
There are several factors that may contribute to a tummy tuck resulting in a boxy shape. These can include a person's native torso contours that simply do not become more curvy with surgery or an excess of subcutaneous fat that may improve with localized liposuction etc. The best way to determine what type of results you can expect is to have a close conversation with your plastic surgeon.It is imperative that you seek the advice of a plasticsurgeon who is certified by the American Board of Plastic Surgery and hasextensive experience in tummy tuck/abdominoplasty. I wish you the best. Dr. Gabbay.