As he waited for the painkiller to numb his face, the 58-year-old was told he would have to fork out before they went ahead, he says.
He had only Ģ30 of the Ģ60 fee - and his bank card wasn't working.
He pleaded to be able to pay the next day but was ordered to dash home to get the money.
Baxter, of Hornchurch, Essex, said: 'I explained that I was a teacher working down the road and showed them my security pass.
'But despite promises I would pay the next day, they refused to remove the tooth until I paid up.
'So I had to drive home and look for my other bank card.
"They were quite happy for me to drive with a completely numb face.~ David returned half an hour later with the money and was forced to wait 40 minutes to see a dentist ~ by which time the anaesthetic had begun to wear off.
'My mouth was beginning to throb again. I nearly hit the roof when they started to remove my tooth,' he said.
'I've never been in the situation where I had to pay up front.
"There was no sign stating the money had to be up front and the whole situation was doubly painful and stressful.
"I literally had to pay through the teeth,' the humiliated teacher later told Daily Mail.
Dentist Tariq Mushtaq, from the Rush Green Dental Practice in Romford, said: 'We told him this is the cost and asked him if he could pay and he said yes.
'We don't do any treatment until they are aware of the cost.'
He added: 'It's NHS policy to have people pay up front before they get treatment.
'The reason is, people say they'll pay tomorrow but tomorrow never comes.
'You can pay the next day if you're in the course of treatment, but all he needed was a wisdom tooth removed.'