Thought this was an interesting article. It's a PDF, sorry about that.
http://www.ata.org/sites/ata.org/files/pdf/Tinnitus Caused by Dental Crowns - Shore, Stefanescu & Martel - Summer '13.pdf
http://www.ata.org/sites/ata.org/files/pdf/Tinnitus Caused by Dental Crowns - Shore, Stefanescu & Martel - Summer '13.pdf