I think you should really take the time to find out if the dental schools require grades or not. There are a lot of schools that say on their website that you may not elect to take the pre-req classes as pass/fail. I literally just googled dental school pre-requisites pass/fail and got some blurbs from random schools:
Indiana:
- All prerequisites must have letter grades; no PASS/FAIL options are accepted
Tufts: All pre-requisites must be taken for a letter grade. No Pass/Fail credits will be accepted, unless it is the policy of the college/university to only offer such evaluation.
Michigan: we will not accept pass/fail or credit/no credit. In addition, a
grade of C- or lower will not be accepted to fulfill any part of the required 50 semester hours of prerequisite courses.
Pacific: Students may not elect pass/fail options in required course work unless a narrative transcript is provided by the college.
Kentucky: Prerequisite course work must be taken for a grade option, not pass-fail.
Once again I just googled these and copy pasted them here, I did not apply to all these schools myself but I just wanted to give you an idea that a lot of the schools want to see letter grades. (and idk if they differentiate between the core sciences and english composition classes either)