It's not usual for actors to undergo some changes when taking on a new role.  Sometimes they gain weight.  Other times they have to lose weight or pack on the muscles.  This actor is taking a much more drastic step for his next movie role. 

Actor Mickey Rourke is taking lessons to master a Welsh accent and also is having his two front teeth removed.  Why?  So he can more realistically play the Welsh rugby player Gareth Thomas in a new movie about him.   Talk about really getting into the role.  Wouldn't it be less painful to just go with CGI special effects?