Indeed there have been cases of prion disease spread through dental offices just as there have been cases spread through tonsillectomies.
No sense in worrying over it at this point in time, alarming as it is. The incidence of this is still miniscule.
Ian, thought of you when I read this. Apologies if it's been posted already:
Enrollment in Arab-language courses is on the rise
http://www.nj.com/news/jjournal/index.ssf?/base/news-2/109688104699130.xml