We were told it wasn't allowed but people wear it all the time, acrylic nails too. I was told to cut my nails during my DS1 year. I thought they were short enough but the perio instructor disagreed. It's also in the student handbook that there are to be "NO" visible tattoos, or unnatural hair color. However, I see tattoos all the time. Even a couple 1/2 sleeves. I recently put pink on the tips of my hair, but since it's covered in clinic I haven't had any issues. I did get an unofficial write up for my earrings being too long. They either have to be studs or very small hoops in clinic.
Each school's student handbook is different, and each instructor has a different opinion of what they'll tolerate.
