Just compare these two photos, both on his left side:
http://hollywoodhairloss.com/wp-content/uploads/2014/04/Johnny-depp-hair-transplant-web.png (2012)
http://images.movieplayer.it/images/2016/02/07/johnny-depp_1.jpg (2016)
Dramatically? hes like a nw2 at most, and hes over 50 years old. Doubt he had a hair transplant. Now Matthew McConaughey is someone with real hair loss ( wears a wig or got work done) Brendan fraser ( guy from the mummies) definately wears a wig though.
Just compare these two photos, both on his left side:
http://hollywoodhairloss.com/wp-content/uploads/2014/04/Johnny-depp-hair-transplant-web.png (2012)
http://images.movieplayer.it/images/2016/02/07/johnny-depp_1.jpg (2016)