Smiling Portrait

Cheek dimples are visible indentations of the epidermis, caused by underlying flesh, which form on some people's cheeks, especially when they smile. Dimples are genetically inherited and are a dominant trait. A rarer form is the single dimple, which occurs on one side of the face only. Anatomically, dimples may be caused by variations in the structure of the facial muscle known as zygomaticus major. Specifically, the presence of a double or bifid zygomaticus major muscle may explain the formation of cheek dimples. This bifid variation of the muscle originates as a single structure from the zygomatic bone. As it travels anteriorly, it then divides with a superior bundle that inserts in the typical position above the corner of the mouth. An inferior bundle inserts below the corner of the mouth.
Real smiles vs. fake smiles
A smile does indeed have great power and great social rewards. However, it has been proven that an authentic smile is much more effective than a counterfeit smile. A smile is an outward sign of perceived self-confidence and internal satisfaction. It seems to have a favorable influence upon others and makes one likeable and more approachable.