1. 
   BTD
   Biological Therapies in Dentistry [periodical, périodique]
   Found op http://www.encyclo.co.uk/local/20895
   
   
2. 
   BTD
   Bored To Death
   Found op http://www.netlingo.com/acronyms.php
   
   
3. 
   BTD
   [Before the Dawn] "BTD (Before the Dawn)" is a song released by the South Korean boy band Infinite. The song is the title track of the group`s second EP "Evolution", released on January 6, 2011. A Japanese version of the song served as their debut single in Japan. It was released in November...
   Found op http://en.wikipedia.org/wiki/BTD_(Before_the_Dawn)
   
   
4. 
   btd
   1) Biological therapies in dentistry
   Found op http://www.mijnwoordenboek.nl/EN/crossword-dictionary/btd/1
   
   

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