For his pricked "wound".....just make sure you clean it. Even though it was a "minor" poke, you never know. Those thorns hurt, I got poked before too. Keep an eye on it... sometimes simple skin abrasions can get infected....and as you know, kids touch everything and anything. Put some antibacterial ointment or Betadine on it perhaps. Once, as a child, I had a real minor skin cut on my calf... and it turned into a staph infection....and it almost ate it's way down to my bone....and i had high fever, chills and became very sick. My doctor almost put me in the hospital. My Dad is the one who knew it originated from my cut... he carried me into the Doctor's office as I could not even stand I was so sick. The cut itself...just looked like a small cut...only like 1/4 inch...but it was not healing quickly. Thus, when I became sick with other symptoms...my Dad looked me over and saw the cut and suspected it. You never know. I really learned from that.
I'm sure your son will be fine though. But every since that happened to me... I am real careful with my kids especially.
As for his teeth, I don't know about that. So can't help you there.
Good luck and take care,
~Susan