Miraculously, the rest of the boy's mouth was unscathed.
"It could have occluded his whole airway and he could have been dead, so it's always better than that," the spokesman said.
The boy had been "really good" despite the injury.
"He was obviously screaming to start off with, but by the time we got there he was calm and he was quite good, actually."
The mother had also coped well.
"She was quite happy - obviously a few things going on, but she was good because if she started panicking, he probably would too. So she did a great job."
The boy was given pain relief and was flown to Christchurch Hospital to get the poker removed.
The Westpac Rescue Helicopter was also called to the Motukarara Raceway, on Banks Peninsula, where an 80-year-old woman had been struck by the wheel of a sulky about 2pm on Sunday.
The helicopter spokesman said the woman had been in the birdcage - the area where jockeys get on and off their horses or sulkies - because she had a horse in a race.
"She was hit very lightly by a sulky that was turning around ... she was knocked to the ground. It wasn't high-impact or high-speed or anything."
The woman fractured her leg in the fall.
She was in a bit of pain but was "relatively stoic" as she was flown to Christchurch Hospital.