DENTAL GROSS ANATOMY: Answers to Sample Questions

WEEK 5 -- October 1, 2007

1. Which of the following statements about the parasympathetic nervous system is false?
   • A. It is craniosacral in origin.
   • B. It has long preganglionic and short postganglionic fibers.
   • C. It facilitates digestion by stimulating peristalsis.
   • D. It increases the heart rate.
   • E. All of the above are true.
   
   
2. The long buccal nerve
   • A. is a motor branch of C.N. VII which supplies the buccinator muscle.
   • B. is a sensory branch of the anterior division of the mandibular nerve.
   • C. conveys postganglionic parasympathetic fibers destined for the parotid gland.
   • D. A and C above
   • E. B and C above
   
   
3. Which of the following statements is/are true?
   • A. The buccopharyngeal membrane of the three week embryo breaks down because of the absence of a vascular mesodermal layer.
   • B. Muscles derived from the first visceral arch are supplied by the mandibular division of C.N. V.
   • C. The muscle of facial expression are derived from the third visceral arch.
   • D. A and B are true
   • E. B and C are true
   
   

   ---

   IDENTIFICATIONS
   1. Lateral pterygoid muscle
   2. Medial pterygoid muscle
   3. Temporalis muscle
   4. Lateral pterygoid plate of the sphenoid bone

   ---

   CLINICAL CASE
   
   1. The swelling is likely associated with a blockage of the parotid duct. If respiratory and cardiovascular function are normal there is little need to call for emergency services.
      
   2. The parotid duct lies over the masseter muscle just anterior to the gland.
      
   3. Postganglionic parasympathetics from the otic ganglion stimulate salivary secretion by the parotid. If the parotid duct is blocked, increased parasympathetic tone associated with eating would lead to a swelling of the parotid gland on the side of the blockage.

   ---

   

   ---