Chapter 1 Facial Assessment

10.1055/b-0040-178119

Chapter 1 Facial Assessment

Introduction

For humans, the face is an important means of communication with the outside world. The face conveys personal characteristics, such as health, emotions, and age, and strongly affects self-esteem. It is, therefore, not surprising that over the years, scientists, philosophers, artists, physicians, and other professionals have searched for the definition and characteristics of an attractive face. However, although beauty is easily recognized, it is difficult to explain, as it comprises a combination of objective, subjective, and cultural factors.

Facial esthetics is the result of a combination of bone pattern, position and volume of subcutaneous tissue, teeth morphology, and even individual personality. According to some studies, human beings prefer averageness (facial traits with average facial measurements of the population to which they belong), bilateral symmetry, harmony, proportion, and sexual dimorphism (Fig. 1.2–1.5). ¹ ,. ²

Cephalometry

In cephalometry, the science that studies the cranial and facial dimensions of the head, landmark points have been established to be used as basic references. These points are called craniometric or cephalometric landmarks and have been precisely determined by various authors. The landmark points are located in anatomical accidents, or in geometric positions, and are important in dermatology for facial assessment and in describing filling techniques. The following landmarks are shown inFig. 1.6:

Cm (columella).
Gl (glabella): corresponds to the most prominent point in the midline, between the eyebrows, and is situated on the frontal bone.
Gn (gnathion): located on the external contour of the mandibular symphysis; it is the most anteroinferior median point of the mandibular symphysis.
Go (gonion): the most posterior inferior point of the mandible.
Li (labial inferior point): this is the median point situated on the lower lip contour.
Ls (labial superior point): this is the median point situated on the upper lip contour.
Me (mentonian): the lowest point on the mandibular symphysis.
N (nasion): the deepest point of the nasal root.
Na (nasal apex): corresponds to the tip of the nose.
Pg (pogonion): the most anterior point of the anterior contour of the mandibular symphysis.
Sn (subnasal): the junction between the nasal septum and thephiltrum.
St (stomion): the imaginary point where the median vertical line of the face, which connects thetrichion (Tr), subnasal (Sn), and gnathion (Gn), meets the horizontal line of the rim of the mouth, when the lips are lightly closed and the teeth are hidden.
Tr(trichion): the point located at the start of the hairline, in the midline of the head.
Trg (tragus).

Proportions

Some specialists believe that a simple way of finding the ideal width of facial structures is to divide the face into vertical fifths, so that each fifth corresponds to the width of an eye (Fig. 1.7). ³

On the vertical plane, the face can be divided into three proportional sections: the upper third (between thetrichion and the glabella), the middle third (between the glabella and the subnasal), and the lower third (between the subnasal and the chin). Moreover, the lower third can be further divided into two parts: one-third from the subnasal to the stomion and two-thirds from the stomion to the chin (Fig. 1.8).

Golden Ratio

The section of a line so that the shortest part is proportional to the longest part, and the longest part is proportional to the entire line, is called the golden ratio. If the shortest part is given a value of 1.0, the longest part will be 1.618 times the length of the shortest, and the shortest will be 0.618 times the length of the longest. The number 1.618 is called the golden number, or phi (Φ)— not to be confused with the number pi (Π)—and can be found in the proportions of human beings (e.g., the size of the phalanges), in nature, and in buildings that are considered beautiful. The controversial Marquardt mask derives from this proportion (Fig. 1.1).