Hello there. I'm a Kiwi down South and I spend way too much time on Tumblr and not enough time plowing through the crap surrounding my Bachelor.
So if gratuitous swearing, fandom-shit (everything from Supernatural and Homestuck, to Dark Souls and Welcome to Night Vale), feminism, progression via-agressive revolution, anarcy and random funny pictures aren't your cuppa, you might wanna leave.
So according to canon, troll teeth seem to generally grow back, but that seems to take some time. What if sea dwellers had several rows of teeth like sharks, so when one tooth breaks, the next one just moves into its place, making sure they always have their full set of chompers? That would be pretty badass imho.
Sadly, our friend here might not be as happy about them.
(Can tumblr user Punpunichu stop bringing sharks into every fucking thing? Absolutely not!)