You mean like tooth(e)? floss? I think you cold create a good site supplying dental hygine products and maybe tooth(e)? whitening products ect. Unsure on value due to the keywords not really matching. probally, as it is now, low 'xx'.
Not a very common term. There are only a few hundred google results. So, I would say reg fee.
If you develop it, I have a domain name that you may want for synergistic effects: BreathFreshening.com (75k google results).