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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Facial N. stimulation during testing of nerve indicated by contraction of muscle
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The correct answer is  The orbicularis oris muscle is a sphincter muscle that encircles the mouth.It lies between the skin and the mucous membranes of the lips, extending upward to the nose and down to the region between the lower lip and chin.It is sometimes called the kissing muscle because it causes the lips to close and pucker. <img src=" /> ref - BD chaurasia 6e vol3 pg 66