Lower Jaw & Chin
JAW & CHIN GENDER
Lower jaw and chin feminization can produce a dramatic or subtle change in the global balance of facial features which is fundamental to the final outcome.
The male jaw has a set of characteristics that can influence the perception of facial gender. It is easier to understand the jaw if it is divided into the mandibular angle and the mandibular body. The mandibular angle in men is usually more square-shaped and has well-defined corners, while the mandibular body typically has a greater volume of bone. This results in a wider lower facial third in men and also gives the male jaw its greater vertical height, an important factor when planning jaw reshaping in FFS.
The male chin also tends to be more square-shaped, with more pronounced and defined transitions between the chin and mandibular body, greater bone volume and a more significant vertical dimension. Gender does not necessarily determine the position of the chin; retro-positioned or over-projected chins are found in both men and women. However, a well-defined, projected chin can improve the overall aesthetics of the jaw-chin region.
The transition between the lower jaw and chin is another key area that must also be dealt with in some facial feminization cases. This area has the distinction of generally corresponding to the point where the mentonian nerves emerge, meaning that it must be handled with great care.
SURGICAL TECHNIQUES AND APPROACH
All of the surgical techniques employed by FACIALTEAM for the lower jaw and chin feminization use small incisions inside the mouth (approaches that are invisible after the operation), assisted by field magnification (surgical loupes that improve and augment the surgeon’s vision), and resorbable material (stitches that dissolve over time, eliminating the need for removal). The osteotomies for lower jaw and chin feminization are executed using latest-generation ultrasound technology, which allows the surgeons to make highly precise bone cuts without damaging the adjacent tissue (nerves, blood vessels, muscles). None of the techniques for lower jaw and chin feminization affect the teeth nor how they meet (occlusion).
In some cases, especially in older patients, the soft tissue may be too slack to fully re-adapt to changes in the lower jaw and chin area. In these cases, surgical lifting of the soft tissues may be required. This type of adjustment should not be done at the same time as the jaw and chin surgery, but several months later when the swelling from the surgery has subsided.
Fortunately, the features of the chin can be significantly modified on several planes: width, height and projection. The changes will vary depending on the patient’s anatomical characteristics and the desired result. The type of technique used will also depend on each patient’s features. For example, a sliding genioplasty sections the chin from front to back, separating the chin segment from the jaw. By removing different segments, the surgeon can modify the height and width, obtaining the desired projection or regression. The segments are fixed using unnoticeable mini-plates and titanium screws, and the incisions are closed with intraoral resorbable stitches. At times, a liposuction is also done to remove excess fat under the chin and obtain a better final chin definition.
LOWER JAW FEMINIZATION
Lower jaw recontouring
Jaw recontouring decreases the bone volume (width), improves and softens the jawline and decreases the jaw height, when necessary, using bone sculpture (high-revolution burring) and osteotomies (specific bone cuts).
For patients who require jaw recontouring from the angle area to the chin, including the body of the jaw and the transition between the jaw and chin, FACIALTEAM has developed a triple approach technique. With this technique, the entire jaw surface can be approached via three small incisions inside the mouth. This prevents major scarring, protects the mentonian nerves (responsible for feeling in the jaw and lips) and accelerates postoperative recovery and the return to normal life.
In cases where it might be difficult to get a good view of specific parts of the jaw (for example, in the rearmost part of the mandibular angle), the FACIALTEAM surgeons use endoscopic techniques to improve their view and control the surgical procedures.
Masseter reduction with botulinum toxin treatment
Mandibular width is determined by different facial structures: the skin, subcutaneous tissue, adipose tissue, musculature and bone. During FFS, we can decrease mandibular width using different techniques on the bone (shaving, osteotomies). For patients with masseter hypertrophy (excessive development of the musculature due to hyperfunction), treatment with several botulinum toxin infiltrations can atrophy the muscles and partially reduce the mandibular volume.
The first botulinum toxin treatment infiltration is done during the facial feminization surgery. The following sessions can be done locally, where you live, or during one of your check-up consultations (when appropriate).
If you are interested in learning more about the lower jaw and chin recontouring tecnniques, please read our chapter on Facial Gender Confirmation Surgery in the most definitive book on transgender healthcare to date:
By Luis Capitán and Daniel Simón
In: Gender Affirmation: Medical and Surgical Perspectives
Editors: Salgado, Monstrey, Djordjevic
Thieme Medical Publisher, Inc.