Dusit
Dusit, 2404 University Boulevard West, Silver Spring, MD, Wheaton, 301-949-4140 (Metro Trip Planner - opens in new window) [Washingtonian | City Paper | openlist | Yelp]
Wheaton is an ethnic food center, and here is one of its Thai places. There are many Thai places in Maryland, and as far as I can tell, they are all excellent.