Muscles of the Face

Summary

This video delves into the intricate world of facial muscles, focusing on three main groups: sphincters like the orbicularis oculi and oris, muscles of facial expression including levator labii superioris, depressor labii inferioris, mentalis, zygomaticus minor and major, and triangularis, which control various expressions from smiling to frowning. It also touches on muscles of mastication, such as the masseter and temporalis, which are crucial for chewing. The video promises a separate exploration of muscles of the hyoid and neck, inviting viewers to continue their anatomical journey.

Takeaways

• 😃 The video discusses the muscles of the face, specifically focusing on muscles of facial expression, mastication, and facial sphincters.
• 👁 The orbicularis oculi is a sphincter muscle that closes the eye, while the orbicularis oris presses the lips together.
• 👃 The nasalis muscle is not a true sphincter but functions to close the nostrils when depressed.
• 😏 The levator labii superioris elevates the upper lip, and the depressor labii inferioris depresses the lower lip.
• 😠 The mentalis muscle, also known as the pout muscle, protrudes the lower lip.
• 😊 The zygomaticus minor and major are involved in smiling by pulling the corners of the mouth upwards and at an angle.
• 😠 The triangularis muscle is responsible for frowning, as it pulls the corners of the mouth downwards and laterally.
• 🦷 The muscles of mastication include the masseter, which elevates the mandible when it contracts.
• 😕 The buccinator muscle does not move the jawbone but compresses the cheeks during chewing.
• 🔄 The temporalis muscle is a synergist with the masseter, also elevating the mandible due to its attachment to the coronoid process.
• 📚 The video will have a separate segment for muscles of the hyoid and neck, indicating further content on the topic.

Q & A

What are the main categories of facial muscles discussed in the video?

The main categories discussed are the muscles of facial expression, the muscles of mastication, and the sphincters of the face.

What is the function of a sphincter muscle?

A sphincter is a circular muscle that guards an opening.

Name the sphincter muscles mentioned in the video and their functions.

The orbicularis oculi closes the eye, and the orbicularis oris presses the lips together.

Why is the nasalis not considered a true sphincter?

The nasalis is not considered a true sphincter because it is not a completely circular muscle, although it does guard an opening by shutting off the nostrils when depressed.

What are the functions of the levator labii superioris and the depressor labii inferioris?

The levator labii superioris elevates the upper lip, and the depressor labii inferioris depresses the lower lip.

Which muscle is referred to as the 'pout muscle' and what is its function?

The mentalis is referred to as the 'pout muscle' because it protrudes the lower lip.

How do the zygomaticus minor and zygomaticus major contribute to facial expression?

The zygomaticus minor and zygomaticus major assist in smiling by pulling the corners of the mouth upwards and at an angle.

What is the function of the triangularis muscle?

The triangularis muscle is a frown muscle because it pulls the corners of the mouth downwards and at an angle.

Describe the role of the risorius muscle in facial expression.

The risorius muscle pulls the corners of the mouth laterally.

Which muscles of mastication were mentioned, and what are their functions?

The masseter and temporalis muscles were mentioned. The masseter elevates the mandible, and the temporalis also elevates the mandible, acting as a synergist with the masseter. The buccinator, while not moving the jawbone, compresses the cheeks.

What is mastication?

Mastication means chewing, so any muscle involved in chewing can be called a muscle of mastication.