Humans are the only hominids to have chins and scientists think that they developed to spread the forces created with eating or stresses on the bone from the tongue during the evolution of speech. The jawbone, or mandible, provides the basic shape with a layers of fat and muscle under the skin providing the detailed appearance
A strong chin is a masculine feature that dominates the lower third of the face in men. Kirk Douglas’ look was dominated by his solid chin and superheroes in comics such as Superman and Batman have always been drawn with square, prominent chins.Although a masculine chin is important for men, the shape of a woman’s chin is very important in her appearance and the proportions of her face. Female faces ideally narrow from the cheekbones to a well-defined chin.
It is important for a chin to be proportional to the rest of the face. Overall 1/3 of the face should be from the base of the nose to the lowest part of the chin. Within this, 1/3 should be from the base of the nose (the subnasale) to where the lips meet (the oral aperture). The other 2/3 is from the oral aperture to the tip of the chin (the menton).
As well as the frontal appearance, the side-on appearance of the chin is important. A strong chin is especially important for men and correction of a ‘weak’ chin is a well-known request. Here a face in profile has just the prominence of the chin adjusted, but the change in appearance for the rest of the face is remarkable.The prominence of the chin is linked to the appearance of the lips as ideally there should be a line running from the chin to the nose with a 4mm space to the upper lip and a 2mm space to the lower lip. This can be seen by resting your finger on the chin and nose and seeing the gap between the finger and lips. Knowing the correct proportions allows for any correction to be done in harmony with the rest of the face.
Another important aspect of the chin is that in the youthful face it blends in with the jawline. Jowls appear over time as the middle part of the face (below the eye) sags with a characteristic, if unwanted, aged appearance. Lines running down from the corners of the mouth, often known as marionette lines, add to this appearance of the chin appearing to be isolated from the jaw.
Fillers are the most common treatment for the chin and lower 1/3 of the face. They can be used to adjust the chin size and shape, and to smooth the marionette lines at the corners of the mouth to blend chin area to cheeks. Fillers can also be used to re-establish the jawline to define it and recreate the straight line of youth.
Botox can also be used in this area. An orange-skin appearance of the skin when the lips are pursed is due to a strong mentalis muscle and this can be reduced with botox. Where the marionette lines are in part due to a strong muscle pull at the corners of the mouth, which also causes a ‘sad’ appearance, botox may be needed in combination with fillers for a full correction.
Sometimes the problem of the appearance of the chin can lie within the mouth. If the teeth are very worn or even absent the mouth, and face, can be over closed leading to a ‘witch’s’ chin appearance. Here a dental correction can be the most important factor and needed before any facial aesthetic treatment will be effective.