Every Plastic surgeon has definitive opinions on this topic. since you asked, I will share mine with you. In general, sutures in surgery can be divided into PERMANENT (Silk, Cotton, Prolene, Tevdek, Dacron, Ethibond etc etc) and DISSOLVING - either short lasting, or longer lasting (Gut, chromic gut, Vicryl, Monocryl, PDS etc). We usually use dissolving sutures when we want things splinted for a short time together BUT are confident that the scar would COMPETENTLY hold things in place after wards. We use permanent sutures when we want to make sure certain things do not separate (Heart valves, vascular grafts, hernias, ports etc). for this reason mOST surgeon repair the abdominal muscles with permanent sutures - to make sure they do not separate. As regards the transverse closure, some surgeons DO use permanent sutures in the deep SFS layer to assure a long lasting lift of the thighs and prevent scar widening - others use only dissolving sutures. I subscribe to the opinions voiced by Dr. Lockwood, the inventor of the High Lateral Tension Abdominoplasty and I use permanent sutures interspersed with long acting dissolving ones in the SFS layer. BUT - NONE OF THESE SUTURES are visible from the skin. Dr. P. Aldea