Does having an otoplasty done make your ear smaller in size?

No: Usually the otoplasty is done to reposition the normal elements of the ear in a more traditional posture.

Prominent: Otoplasty is a surgical procedure that is performed to treat prominent ears. The ears are essentially pinned back so they don't stick out as far. They appear smaller from the frontal view, however, the size of the ears are not reduced. http://www.dassmd.com/ear-pinning-beverly-hills.html.

Just appearance : The actual size of the ears will be the same, but will appear smaller as it won't stick out so far.