The jaw is arguably one of the most important aspects of a face. Throughout the defining beauty series, we’ve used and explained the concept of a ‘universal beauty standard,’ something that people from all cultures, races and creeds find attractive, as they’re indicators of basic genetic health.
A recessed jaw creates malocclusion, a condition where the upper and lower jaw don’t line up correctly and this leads to a whole host of problems from uncomfortable sleep apnea to painful TMJ.
It’s pretty clear to see why the jaw is such a strong indicator of genetic health, because it’s actually correlated to your health, unlike other features which only suggest it. Selectively, we prefer partners with well formed jaws for their sexual dimorphism, where males are expected to have a longer jaw body and steeper ramus and females are expected to have a shorter, shallower one.
Before we delve any deeper into what makes an attractive jaw, lets cover the terminology:
When plastic surgeons and orthodontists prepare for jaw surgery, they consider a few key parameters that influences the jaw’s final shape. The first and most well known one is the lower mandible, or what’s commonly known as the jawline or jaw body. In art anatomy it’s often taught that the mandible should line up with the naision of the face.
A longer, more prominent mandible, within reason, is more beneficial to increasing bite force as the pterygoid (ter-e-goid) muscles have a longer lever arm to generate more torque with. This is one of the proposed reasons for why we’ve always found strong jawlines attractive from an evolutionary survival point of view.
The next important part is the ramus which again helps with bite force, but not as much as the mandible. Men have a steeper ramus which goes downwards and doesn’t help make the lever arm longer to amplify force. The length of the ramus largely determines the face shape from long and oval to short
and square. In men rammus length determines, for lack of a better word, how ‘masculine,’ your jaw looks and vice versa in women, as it’s one of the main points of sexual dimorphism in the jaw. Sexual dimorphism referring to biological differences in men’s and women’s anatomy.
The Jaw Angle
The ramus does play a role in attractiveness as it forms the next parameter, the gonial angle. The gonial or jaw angle is the angle the ramus makes with the mandible and can vary from 90° to 140° with the population average being
within 128° +/- 2.36° for males and 126° +/-2.41°. More acute gonial angles result in square, masculine faces while larger, more obtuse angles result in a rounder, feminine appearance.
Bigonial width is a measure of jaw width from gonion to gonion (the apex of the mandible and lower jaw). Men tend to have larger bigonial widths while women have smaller ones. Interestingly, some may mistake large masseter muscles as being the bigonial width, however this is strictly a measure of bone structure and so muscles which vary in size day to day
cannot be included. The majority of men who go in for jaw surgery are concerned with improving their bigonial width. It’s the last milestone for the Brad Pitt’esque jawline, where many have strong mandibles, but few have the Hollywood width to acheive the masculine square face look.
From the journal of Cranio Maxillo Facial Surgery 2016, ‘The Ideal Male Jaw’
Esthetically, a fuller,augmented gonial angle portrays a look of masculinity, and a stronger jaw is often desired
For the purposes of this experiment, the participants are expected to choose based on the jaw that’s ideal for a male model and to exclude prominent cheekbones or other midface features from their criteria.
Model Jaw Shapes
As mentioned in the difference between universal and cultural beauty standards, humans universally find averageness in features conventionally attractive. Number 1 to you might not be what the average man looks like on the street but his features are average in proportion to his face unlike #2 which has an above average rammus length and bigonial width and #4 with an above average bigonial angle.
In the first warmup question, 52% chose the first image, which is honestly surprising because one would expect #3 or #5 to win out as they have more defined midfaces, alongside the model tier jaws. However, excluding young Depp’s cheekbones #1 has the most well formed, ‘conventional’ jaw. The second option has a very extreme ramus length, giving him an overly blocky appearance, while #4 has a lower third (jaw) disproportionate to his face.
Influence of Facial Fat
The following question in the research paper delves into how excess skin and fat conceals the jaw and is not aesthetically pleasing with 74% agreeing. Staying lean has a huge benefit to facial attractiveness and skin aging as it reduces the size of facial fat compartments that mobilize themselves through ageing, best explained here.
Downward Cranio-facial Development
The last and most important question goes over finding an ideal jaw shape in terms of side profile and frontal lower third. The results are about what one would expect if you searched ‘handsome guy’ on google images. Cases like number 6 got 0% rating it as good out of 800 participants. The jaw has a poor bigonial width, and the entire structure is angled downards instead of prominently forwards.
This is seen in cases of children who mouthbreathe where a constant open jaw fails to provide the support needed to the upper jaw and maxilla to push it up and outwards and so the entire face sags. The puffy under eye almost out of frame, is a result of the recessed maxilla and midface and even in the photo he has his mouth open.
Compare this to how drastically different number 10 is. The bigonial width is wider, pulling the mouth out wider making the entire face shape shorter and squarer, which results in a shorter facial width to height ratio which is seen as attractive in men.
Foward Cranio-facial Development
Jaw Placement and Length
The trial was repeated but this time removing the chin to find ideal jaw placement and length in relation to the face. There was a larger spread in results but the mode result still indicated square, short faces like Brad Pitt’s to be ideal and longer jaws, (i.e. longer faces) to be unideal. Interestingly enough square faces have the strongest bite force as the mandible is most perpendicular to the fulcrum of the jaw in these face types which backs up the hypothesis that the an attractive jaw correlates to bite force dating back to our evolutionary survival ancestors.
Jaw Side Profile
The final trial considered the side profile of the jaw. Recessed jaws didn’t score well like #6 but the best rated jaw wasn’t the most prominent one surprisingly. Jaws like #9, rated lower than jaws like #15, both being super prominent and masculine jaws, but differing by their gonial angles with #15 having the population average angle of 128°. The winning jaw angle was #12 which has a lower rammus length leading to a more feminine, ‘pretty boy’ look like your average boyband member.
Although only one jawline can be the winner in this study, the differences between the prominent, well formed jawlines is very close whereas the recessed jawlines are a unanimous no. If theres one thing to ever recommend changing, it’s fixing a recessed jawline as the health issues only get worse with age, that’s even before considering aesthetics.
The preferred jaw angle had these characteristics: 130° in face profile view, intergonial width similar to facial width, vertical position in frontal view at the oral commissure or at least not below the lower lip, jawline slope in the face frontal view nearly parallel to (with a maximum 15° downward deviation from) a line extending from the lateral canthus to the alare, ascending ramus slope 65°–75° to the Frankfort horizontal, and curvature in the oblique view visible from earlobe to chin and not pointy.
Proposed Causes of Jaw Recession
Having a prominent jaw is really the gold standard universally, arguably more so than any other feature. So what causes a recessed jaw? One reason is due to mouth breathing where the constantly open jaw doesn’t give the upper jaw any support to push upwards and away from, creating a recessed maxilla and subsequent downward angled jaw. Another reason is due to poor tongue posture which is a more recent proposal of Dr Mike Mew, and the final reason is due to our soft diets, as indicated by Dr Weston Price in the late 1900s.
Further Reading / References
- The ideal male jaw angle
- appropriate biting substrate and standardization of bite out-lever