Dr MacMillan's big shave was arranged for Saturday night, by which time he had raised $8943. He needed an extra $57 to reach $9000, so he asked his audience to donate just a bit more money.
Friends Chris Atkinson and Nick Smith offered to shave their mullets off to bring the total up, and an extra $700 was raised. The local Nga Uri o Te Ngahere Trust also pitched in, giving $1000.
"It's just wicked," Dr MacMillan said. "I was pretty certain I would never shave my beard off for any reason, but this was a great reason."
Joanna Dabrowski, assistant to the Ruel Foundation chief executive, said the result was "absolutely fantastic".
"We really struggle for funding, partly, I think, because it's an overseas-based charity. We really want people to know how important the Ruel Foundation is.
"In New Zealand, from the moment you're born, surgeries will be taken care of, whereas we're dealing with children living in countries where that is not an option because of isolation, or because of poverty. And there's no Government health system for these children."
Mrs Dabrowski said Dr MacMillan's offer to fundraise for the charity was "like winning Lotto".
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"With this kind of money, we can do a lot of surgeries. I can't say exactly how many because it's different depending on what area we go to ... I wouldn't be surprised if we end up doing surgeries for at least 200 children this year. It might even be more than that."
The foundation normally looked at 60 children a year.