Lip anatomy Flashcards
Lip anatomy
Where is the oral fissure and what is the size of oral fissure controlled by?
Describe the structure of the lips starting from the outermost skin to the innermost mucosa? What are the differences between skin of lips c/f to rest of the body?
What do the lips enclose? Where are the labial glands?
Describe the neurovascular supply and how do you avoid important vessels during injection?
Lip anatomy
Oral fissure is a slit like opening of the lips that is controlled by the muscles of facial expression and jaw movements. Muscles of facial expression that affect opening include:
-zygomatus major and minor
-levator labii superioris; levator labii superioris alaeque nasi and levator anguli oris
-depressor anguli oris; depressor labii inferioris
-obicularis oris **
-buccinator
Structure of lips
Lips are covered externally by skin and lined internally by mucosa. From outermost to innermost:
-epidermis: 3-5 layers unlike rest of body 16 layers
-dermis: collagen fibers and elastin
-hypodermis: few fat cells
Skin of lips are much thinner in comparison to the rest of the body and have less oil glands-> prone to dehydration.
Because they are thinner, blood vessels are more visible giving lips pink appearance
Lips enclose orbicularis oris muscle, blood vessels (superior and inferior labial arteries) and pea-shaped labial glands that open up into oral vestibule.
Neurovascular supply
Lips are supplied by superior and inferior labial arteries (branches of facial artery). These are located 4-5mm behind orbicularis oris muscle, 2-3mm above wet-dry border
Describe the surface anatomy of lips
Philtrum of lips-base of nose to lips. They contribute to the shape and appearance of cupid’s bow
Cupid’s bow-M shaped bow of upper lips. Contribute to feminity of lips
Vermillion border-demarcation between skin and red part of lips. can be enhanced in aesthetic injections
White roll- raised part of vermillion border
Tubercles- 3 tubercles of upper lip and 2 tubercles of lower lip
Oral commissures- smiling corners of lips. Controlled by levator anguli oris; zygomatis major and depressor anguli oris
Describe the differences in lip appearances between caucasian, black and asians
