Which statement is true about disc displacement with reduction (DDwR) features?

• A. It presents with intermittent joint noises and sometimes catching; normal MMO
• B. It never has joint noises
• C. It has limited mouth opening
• D. It is identical to myofascial pain

Answer: (A)

The concept being tested is recognizing the classic features of disc displacement with reduction in temporomandibular disorder. In this condition, the articular disc sits anterior to the condyle when the mouth is closed, but it reduces back to its normal position during mouth opening, producing a distinctive click or pop. This movement pattern leads to intermittent joint noises and, importantly, a normal or near-normal maximum mouth opening. So the statement describing intermittent joint noises with occasional catching and a normal MMO fits perfectly.

The other ideas don’t align with DDwR. There are typically noises when the disc reduces, so saying there are no joint noises isn’t correct. Limited mouth opening is more characteristic of other conditions, such as disc displacement without reduction. And myofascial pain involves muscle tenderness and referred pain rather than the joint noises associated with disc movement, so it isn’t identical to DDwR.