"Dewlap" is defined as "the pendulous skin hanging under the throat". I cross referenced this in several medical dictionaries and they all had the same definition. It is also known as "turkey wattle" which I have seen here on the forum. It is a somewhat normal temporary condition from radiation damage to the eustacian tubes and other drainage (lymphatic?) channels I imagine. The weight loss also amplifies it. Most of us had it as well. I had lots of issues with fluid buildup and difficulty hearing in the early post Tx - nothing to freak out over (it even showed up on all of the early MRI's).

Although I have the greatest respect for dental oncologists they are just specialed dentists. I would run it by the MO and RO just to give you some piece of mind. My MO was the PCP for the greater part of my Dx and Tx.