Most people in most places dread an encounter with a dentist. In the wilds of South Sudan it amounts to a fascinating surprise. Michael Deng Ngok is the only dentist for thousands of miles. Even he has no idea how many potential patients he caters for. A rough guess comes to more than one million.
I imagine a few people come to dentistry with a sense of mission. Many are presumably attracted by the income. But there are few places in the world where to do so is in itself revolutionary.
Michael chose the profession in a place where many of his countrymen were, until recently, expected to chisel out their bottom teeth in order to show they had come of age.
For generations the Nuer and Dinka tribes, rival herding peoples who make up the majority in the south of Africa's largest country, removed the teeth between the incisors on their bottom jaw to mark the entry into manhood.
Failing to do so marooned you eternally in boyhood. Any would-be Peter Pans would find themselves becoming figures of fun to any girls they hoped to impress.
I have to admit that I expected Michael to have an eloquent defence for a unique cultural practice, or at least some patience with it. Instead, he was having none of it.
"It needs to be stopped now," he said, before explaining the terrible speech impediment it leaves in its wake, the gradual disintegration of the jaw and the difficulty of chewing when you've voluntarily pulled out your main tools for doing it.
Having studied in Khartoum and Cairo, Michael, who is 26, is ready to bring oral hygiene to the masses in one of the least developed places on earth. So it is to his huge frustration that while some people are prepared to listen to him in his one-man campaign to remove teeth-pulling from the rites of passage, the only thing anyone ever asks for at the clinic is to have their teeth removed.
"They only come when there is so much pain, and they want the tooth taken out."
Patience is a virtue
The word "remote" means different things to different people. By most gauges it's possible to agree that Bentiu, the capital of Sudan's Unity State, fits the bill. It's not a place you get out of in a hurry.
Having made the mistake of flying there with South Sudan Air Services, I was stranded for long enough to think about this, as the plane was three days late. Excuses ranged from the pilot being tired to the plane having gone to Nairobi for repairs.
On the second day, in a flash of impatience, I decided it would be better to drive to Juba, the South's capital and the nearest international airport. The conviction lasted as long as it took me to discover that the drive was roughly five days, the road was "quite rough", and I would need at least two soldiers with me.