The cheek constitutes the facial periphery, plays a key role in the maintenance of oral competence and mastication, is involved in the facial manifestation of human emotion, and supports neighboring primary structures.
The most common causes of acquired cheek defects are tumors, burns, and trauma; while congenital abnormalities in cheek contour may be due to facial clefts, vascular anomalies, or facial wasting syndromes. [Source: Wikipedia 
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