Plain old Crest.
I've used it since the mid-1950's, and with the exception of a tooth that was broken by the charging handle of an M203, every tooth in my head is original and cavity-free for 50+ years.
I brush 3 times a day and floss twice a day. My biannual dentist visits last about 30 minutes each (one of which will be Tuesday morning).
When I see people with nasty teeth I just shake my head, knowing that it's so simple to maintain oral health. And knowing that the mouth is the gateway to the rest of the body, and knowing the issues that having nasty, rotted teeth can cause with the rest of the body, I'm glad I've taken care of my teeth.