What is the SMAS?
The earliest facelifts were single layer procedures that only tightened the skin. Good results were possible but longevity and scar quality were limited by high wound healing tension on the skin. In the 1970’s surgical anatomists described the Superficial MusculoAponeurotic System, or SMAS. This is a dense connective tissue layer in the cheek lying between the subcutaneous fat above and the muscles that control facial expression below. Surgeons soon began tightening this layer to increase lifting power as well as improve both procedure longevity and scar quality by taking tension off the skin. Skin tightening is still important but its lifting role is secondary to the SMAS effect.
What does "Deep Plane" mean?
In the 1990’s Sam Hamra, a prominent Texas plastic surgeon, popularized the deep plane lift. This procedure raises the skin and the SMAS together as a single layer. This method provides better circulation for the overlying skin since it is a double layer, but poses a greater risk of injury to the facial nerve branches just deep to it. Most traditionally trained plastic surgeons have abandoned the deep plane lift because there has been no proven aesthetic advantage ever demonstrated in results.
How is a SMAS lift different?
A SMAS lift raises the skin and SMAS layers separately, rather than together. The advantage is that the SMAS and skin can then be tightened in slightly different directions. This allows better control and customization in restoring individual facial shape. The deep plane method is limited to one direction of tightening. Additionally, there are several variations of SMAS layer treatment: either excising part of it or folding it on itself for patients whose laxity is primarily limited to the jowl area, and more extensive inward SMAS lifting for those that also need central cheek lifting. The deep plane method can only do the same thing for every patient. This is regardless of individual differences in facial shape due to bone structure, soft tissue bulk, and skin quality. For these reasons, SMAS lifts are preferred.
Why is there a controversy between SMAS and deep plane lifts?
There actually is no controversy based on technique merits. Procedure preference reflects surgeon training instead. Plastic surgeons from traditional plastic surgery programs use SMAS lifts. “Facial plastic surgeon” is a self-proclaimed title by graduates of ear, nose, and throat (otolaryngology) programs. They do not perform aesthetic procedures below the neck. They exclusively use deep plane lifts for reasons unclear.