COM Anatomy & Physiology of the Orofacial Complex 3 — Questions and Answers
Question 1: The lateral pterygoid muscle's inferior head is primarily responsible for:
- Elevating the mandible
- Protracting the mandible and initiating opening (Correct answer)
- Retracting the mandible
- Lateral excursion toward the ipsilateral side
Correct answer: Protracting the mandible and initiating opening
The inferior head of the lateral pterygoid protracts the mandible and assists with jaw opening by pulling the condyle and disc anteriorly.
Question 2: Which structure separates the oral cavity from the nasal cavity?
- The velum (soft palate)
- The hard palate
- The nasal septum
- Both the hard and soft palate together (Correct answer)
Correct answer: Both the hard and soft palate together
The hard palate forms the bony floor of the nasal cavity anteriorly, while the soft palate extends this separation posteriorly; together they form the roof of the mouth and floor of the nasal cavity.
Question 3: The genioglossus is the largest tongue muscle and its primary function includes:
- Retracting and humping the tongue
- Protracting the tongue and depressing the central tongue body (Correct answer)
- Elevating the tongue tip only
- Widening the tongue laterally
Correct answer: Protracting the tongue and depressing the central tongue body
The genioglossus, originating from the mental spine of the mandible, primarily protracts the tongue and depresses the central dorsum creating a trough shape.
Question 4: Which of the following best describes the role of the levator veli palatini during swallowing?
- Tenses the soft palate horizontally
- Elevates the soft palate to achieve velopharyngeal closure (Correct answer)
- Retracts the uvula posteriorly
- Lowers the soft palate to open the velopharyngeal port
Correct answer: Elevates the soft palate to achieve velopharyngeal closure
The levator veli palatini is the main elevator of the soft palate, lifting it superoposteriorly to close the velopharyngeal port during swallowing and speech.
Question 5: The frenum of the tongue (lingual frenum) connects the tongue to the:
- Hard palate
- Floor of the mouth (mucosa overlying the mandible) (Correct answer)
- Soft palate
- Lower lip
Correct answer: Floor of the mouth (mucosa overlying the mandible)
The lingual frenum is a fold of mucous membrane connecting the inferior surface of the tongue to the floor of the mouth.
Question 6: The mylohyoid muscle forms the muscular floor of the mouth and is innervated by:
- CN XII (Hypoglossal)
- The mylohyoid nerve (branch of V3) (Correct answer)
- CN VII (Facial)
- CN X (Vagus)
Correct answer: The mylohyoid nerve (branch of V3)
The mylohyoid is innervated by the mylohyoid nerve, a branch of the inferior alveolar nerve from V3, and elevates the hyoid and floor of the mouth.
Question 7: In the context of orofacial myology, the 'resting posture' of the tongue should ideally be:
- Against the lower incisors with slight forward pressure
- Resting on the floor of the mouth
- With the tip and body resting against the anterior hard palate (Correct answer)
- Pressed against the upper incisors
Correct answer: With the tip and body resting against the anterior hard palate
Correct resting tongue posture involves the tongue tip positioned at the incisive papilla with the body gently contacting the hard palate, maintaining the palatal arch.
COM Anatomy & Physiology of the Orofacial Complex 3
The lateral pterygoid muscle's inferior head is primarily responsible for: