I have 10 years in the dental industry. Used to travel the country giving seminars to Dentists about how to "Build Your Practice with High Technology" plus was in management with several top high tech Dental companies.
Are you talking about Dental products consumers would be interested in I assume? Without doing any research at all my guess is not many search for "dental products" plus you wouldnt make much selling tooth paste and stuff that people can easily buy at the grocery store.
I know LOTS of people search for a couple dental products directly,
that happen to have HIGH paying affiliate programs.
(But these products may also have high competition so check that out if you are a newbie.)
Tooth Whitening, bleaching etc. Check those types of key words and you'll find lots of searches. There are several affiliates programs, but the best I know iof is managed by PartnerCentric - a 5 Star client.
Check out the BriteSmileAffiliate Program. It pays up to $60 per sale.
The other really good Dental affiliate program is
DentalPlans.
They pay around $40 per sale depending on which program you join.
Hope this helps and best of luck!