I dont know, I had a dentist submit one electronically for me and Im pretty sure he didnt sign it. How can you really sign it if its done in word, the only signature he can do is typing his name.
if u want ur LOE to be electonically done, indicate so on AADSAS.
They will require ur doctor's/teacher's whoever's personal e-mail, and from there they will e-mail him/her all the crap he/she needs to do (fill out a form, how to e-mail the LOE etc).
don't worry. so no, they will not sign it..i think the personal e-mail is an indication that your LOE will be unlooked or private.
As was said before it will be an electronic signature. Unless aadsas will accept pdf. files in which the dentist could scan the document. I don't think it is that critical.
I called AADSAS, they told me that when the evaluator uploads the file, it's considered their digital signature. No hand written signature is necessary.