[Facial rejuvenation and concentric malar lift: the FACE RECURVE concept].
Cell ageing is responsible for the increasingly creased appearance of our skin. The ageing of the structures of the face is attributed primarily to the effect of gravity on the tissues. The theory expounded below sets out to prove that the main and initial cause of this ageing is the repeated contractions of the mimic muscles. This concept attributes only a secondary role to gravity in the ageing process, which is initially brought about by muscular contractions. An MRI study recently made it possible to demonstrate the anterior convexity curve of the mimic muscles in the young subject. This curve is due to the existence at the back of these muscles of a deep fat pad. In the young subject, the extent of its convexity and its location give a specific, youthful character to the movements, in terms of direction and amplitude, of the facial muscles. With age, the muscle gradually straightens and shortens due to the repeated contractions that expel the underlying fat and increase the tonus at rest. The application of these new findings to the ageing of the face gives rise to new technical possibilities both in the field of medicine and aesthetic surgery. These new techniques have the same targets: segments of the mimic muscles (maintain over time a good muscular curve and a low tonus at rest) and the underlying fatty convexities. As far as medicine is concerned, the combination of botulinum toxin and filling has proved its worth. But two technical elements are new: the filling products must, at several points, be injected primarily behind the muscle to treat the depressions naturally and restore the initial curve of the overlying muscle. A very low number of units (a quarter to one unit) of botulinum toxin must be injected into certain muscles to diminish the tonus at rest of these muscles without diminishing their strength in maximum contraction. In surgery, new possibilities to treat premature ageing include procedures that combine segmentary muscular weakening, micro liposuctions and retromuscular reinjections. The advantage with regard to the medical procedures is greater stability over time and the greater precision of these muscular actions (one third of a muscle can be weakened for example) and the fat reinjections can be more stable. These procedures can be performed under local anesthesia. In cases of more advanced ageing, surgery offers new treatment possibilities that include, for the midface region, the concentric malar lift. It replaces, on the orbital rim, the sub-orbicularis oculi fat that has descended eccentrically as a result of the contractions of the orbicularis oculi muscle. The procedure, using the subperiosteal detachment plane, is therefore stable over time. At the same time, specific muscles are weakened. The aims of restoring fatty volumes and muscular tonuses are thus achieved. Similarly, in the neck, the platysma muscle is specifically weakened. Each area is studied in line with its specificities. For the first time, the skin tension of the facelift has no more to be maximum to treat the relief of the jawl line, of the palpebro malar groove and so on. The skin tension becomes moderate, just to remove the excess of skin. The relief is faded with the specific muscular and fatty action. The name of this new concept is Face Recurve.