286K views · 2.9K reactions | Know your facial muscles, Vol. 4: orbicularis oris, risorius, mentalis, buccinator, depressor anguli oris, depressor labii inferioris. Learn human anatomy fast at Anatomy.app!易 https://anatomy.app #anatomy #medschool #medstudent | Anatomy.app | Facebook

The risorius may be a small muscle, but it plays a big role in smile dynamics and it’s one injectors must respect. 🔎 What injectors need to know: Anatomy: lies above the buccinator, with its origin on the surface of the masseter. Function: contributes to smiling by pulling the corners of the mouth laterally. Clinical relevance: it’s often affected indirectly during masseter toxin treatments. → If you relax the risorius by accident, patients can lose smile width or expression, especially after j