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The power of a smile is in its ability to engender feelings of happiness and positivity. The smile has been rated as the facial expression with the highest positive emotional substance and has been shown to reduce stress. However, not all smiles are equal in their emotional content and social impression. A genuine enjoyment smile (Duchenne smile), is a positive display of facial emotion characterized by upper lip and oral commissure  elevation in combination with periocular wrinkling.

Facial paralysis affects our ability to smile and along with it our ability to project positive feeling. Through our pioneering work and innovative techniques we are restoring genuine smiles.


There are several muscle groups that help form a smile. The upper lip  and corner of the mouth are lifted  and pulled by muscles that contract in different directions ( vectors ). The multidirectional effect of these muscles are necessary to form a full smile. The traditional gracilis flap for facial animation is a single segment of muscle that reliably supports and pulls the corner of the mouth  in one direction when smiling. The resulting smile is a single  vector  or unidirectional smile commonly described as the Mona Lisa smile. 

The multivector gracilis flap is a novel technique for restoring a fuller smile. With this technique, muscles are placed to move the lip in multiple directions.

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IA, A full smile is the result of a multivector (black arrowheads) and multizonal action (blue triangle, square, and circle zones) of the smile muscles. Upper lip and commissure elevation results from muscle action within the square and triangular zones respectively, and periorbital wrinkling in the circular zone. B, The upper and lower lip frames the smile display zone. In this framework are the components of a smile including the gingival scaffold and displayed teeth. C, The smile display zone. D, The paralyzed upper lip drapes over the smile display zone obscuring the gingival scaffold and limiting dental display. Correction of the paralytic labial drape requires a multivector muscle action (blue arrowheads). E, The horizontal and vertical components of the smile display zone can be analyzed by measuring the maximal gingival scaffold width and interlabial gap at the midline and between the canines.


Over the years as I analyzed  results of patients who have undergone facial reanimation surgery, it became clear that while we were  significantly improving  facial symmetry and restoring movement, the resulting smile was not consistently joyous. A joyful smile, the type describes as  Duchenne smile, reflects  a strong positive emotion. In the joyful smile

 lips are evenly lifted to fully display the teeth and part of the gums, the smile lines deepen, the cheeks form a mound and the eyes narrow into a squint. This type of smile is different from the tightlipped Mona Lisa smile.  The multivector gracilis flap is my innovative answer to achieving a more joyous smile. Below are examples of full smile restored using the multivector gracilis flap. 

Multi vector gracilis flap with 2 muscle paddles lifting

the  upper lip and oral commissure in divergent directions to produce a full smile. Note that before surgery the upper lip draped over the upper teeth with only one tooth exposed on the paralyzed side. Equal number of teeth ( 4 ) are exposed on both sided after the reconstruction. by Dr. Kofi Boahene.

Complete facial paralysis
multivector gracilis  Dr. Boahene
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After multi vector gracilis flap perform

Kathryn loss her facial movement after  surgery to remove a brain tumor. Read about her journey with Dr. Boahene to regain her smile. 

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