Which of the following statements is true concerning the functions of the posterior bilaminar retrodiscal pad during normal temporomandibular joint (TMJ) osteokinematics?
a. The elastic superior lamina allows disc translation anteriorly along the articular eminence during mandibular depression.
b. The elastic inferior lamina serves to enhance disc motion during mandibular depression.
c. The superior lamina is inelastic and serves to tether the disc from forward translation.
ANS: A
The bilaminar retrodiscal pad is highly innervated with an ample blood supply and is often the
source of pain at the TMJ. The two bands of the retrodiscal pad each serve a different purpose. The
superior lamina is very elastic and allows the superior band to stretch with forward translation of
the disc. Its elastic properties help to reposition the disc posteriorly during mouth closing. The
inferior lamina is inelastic and serves to tether the disc, limiting anterior translation, but does not
assist with repositioning of the disc upon mouth closing.
You might also like to view...
As you arrive at the scene of a house fire, a very upset man screams at you to help his young son, who is trapped under a piece of burning wood on the ground. Which of the following should you do first?
A) Perform an initial assessment on the patient. B) With the father's help, grab the boy by the arms and pull him from underneath the wood. C) Size-up the scene before acting. D) Use a blanket to put out the fire on the piece of wood.
How many alpha and beta chains are present in a HbA molecule?
a. 141 alpha and 146 beta chains b. 2 alpha and 2 beta chains c. 146 alpha and 141 beta chains d. 1 alpha and 1 beta chain