The shape of the lower jaw has an influence on the appearance of one’s face. Besides the shape and prominence of one’s chin in the front, the other important jaw features are that of the paired angles in the back. The more prominent or square the jaw angles are, they can enhance the masculine features ofa man and can give the impression of strength and confidence in a woman. When the jaw angles are too prominent, however, the jaw can be disproportionately wide as compared to the rest of the face. This may create a very square-shaped face and is the motivation for aesthetic jaw angle modification surgery, also known as a gonioplasty. (jaw angles are also referred to as the gonial angles)
Jaw angle bone modification is done to soften the face and make for a less square or more oval-shaped face. Some may call this creating a more feminine jawline and this is certainly true for a woman considering the procedure. Fewer men undergo gonioplasties because the square jaw is a desired masculine feature but there are some men whose jaw angles are exceptionally prominent who want modification as well.
When considering jaw angle modification, it is extremely important that one understand that there are different techniques for doing it…with different aesthetic outcomes. The traditional and most commonly used method is jaw angle removal surgery. This is always referred to as jaw angle reduction but this is a misnomer. Reduction implies the bony angle is preserved but reduced. In reality, the entire jaw angle is simply cut off or removed. From incisions inside the mouth, the junction of the back part of the jaw and the lower border of the jaw is essentially cut off. This not only softens the jaw angle but also raises the line of the jaw from front to back.
For many women, the elimination of the jaw angle (and raising the height of the back part of the jaw up to a horizontal level of the mouth) is aesthetically advantageous because it is a feminizing procedure. It is also the most effective way to thin the width of the face (jaw angle to jaw angle) because the full-thickness of the jaw bones in this area are removed. Given that that each jaw angle is 1 cm or more thick, one can narrow the lower facial width by up to 2.5 cms. For men, however, the total loss of the jaw angles may be aesthetically advantageous and must be carefully considered. I have consulted more than one man who wanted jaw implants to replace jaw angles that have been cut off.
The other technique for gonioplasty is true jaw angle reduction. In this technique, the jaw angles are not cut off but thinned by burring reduction. The shape of the jaw angle is preserved but the bone is thinned. Its advantage is that the jaw angle is not eliminated or raised but its disadvantage is that it can not achieve as much narrowing. This is because the full thickness of the bone is not removed but thinned. This changes the amount of transfacial width reduction at the jaw angles to maybe 1 to 1.5 cms.
In lower facial gonioplasty, the two available techniques are removal (excisional gonioplasty) and reduction. (reduction gonioplasty) Their effects on the jaw angle and the amount of width reduction are different. The use of the term ‘jaw angle reduction’ is often misunderstood and may lead to undesired jaw shape outcomes if done in a standard fashion for every patient. This may lead to some unhappy patients seeking jaw angle implant reconstruction later.
Dr. Barry Eppley