The Hopkins Biotechnology Masters does not require any LOR's or GRE scores (at least when I was accepted, I would recommend contacting them to make sure).
Yes it is a "cool" masters that has interesting courses, but they offer general courses that will help you for dental school; pharmacology, physiology, neurobiology, etc. Thus far I've taken Advanced Cell Biology I & II, Molecular Biology, Infectious Diseases, Computers in Molecular Biology, and Radiation Biology as my science courses. I've also signed up for Immunology and Neurobiology in the spring.
They also offer a few non-science courses, I will have taken 2 when I'm done the program (thus 8 science courses). However, they were very helpful, dealt with business types (e.g.-LLC, Corporation, etc.) and patents/copyrights etc.
I had no business or legal experience and this will help me in the future with practice decisions, or at least give me a background in the area. The patent/copyright etc. are good if you are interested in doing research, as you should have an idea about intellectual property.
Personally I looked at the Barry masters before, and it is great. But for me, I want the M.S. to prepare for dental school AND give me a unique perspective in science (such as the radiation biology course). Many non-thesis masters will give you similar classes to the first year of dental school, and that is great. But I personally wanted to mix in interesting material that will not just be purely "prep" for dental school.
And by no means have I recieved any negative comments about the program, Hopkins has a decent name in science and medicine, whether that matters to you are not. Plus if you did it part-time, you could do research at Hopkins med school/hospital (which I did), it was a great experience and certainly something to add to my resume.
I was also accepted to PCOM's certificate program, but I chose Hopkins mainly because of these reasons and the fact that it is a real degree vs. certificate.