AN abscess, or a "poisonous pocket of pus" as my alliterative dentist described it, curtailed my coverage of David Cameron's campaign visit to Stockton South on Monday.

The Prime Minister was due there at 2.30 but my tooth hurty had been going on all weekend. And not just a little hurty, either.

Everyone I've explained my predicament to has begun their response: "There's nothing worse..."

And they may well be right. It's the sort of inescapable pain that gnaws into your bone. It fills your head with a chainsaw of noise, but it is impervious to ibuprofen and it laughs in the face of paracetamol.

If I'd made it to see Mr Cameron, I might have told him how, on Sunday, the pain had become so bad that for the first time, I'd dialled 111 for NHS direct. I got through within two rings – good. A nurse called me back within ten promised minutes – very good. But she just gave me a lecture on not taking too many painkillers and said that the Darlington emergency dentist might call back before he finished his duty in two hours – he didn't.

So next morning, I was up early enough to win my dentist's last emergency appointment in the day's great dial-up lottery. The appointment was at 1.55; Mr Cameron was at 2.30pm. I put the pain in my head above the pain at the head of the country... (sorry, is that a bit harsh?).

If I had made it, the toothache might have made the meeting revealing. A couple of weeks before the 2010 election, Prime Minister Gordon Brown held his cabinet at Durham Johnston School and I was invited to wait for him afterwards on the leather back seat of his car. As I was recovering from a knee operation, I had my crutches on either side of me, and only half of my mouth was working due to dental issues.

Mr Brown tumbled into the seat beside me like a sack of spuds. He put his head to the car floor and then threw it backwards up to the car roof, using his whole hand to sweep through his hair.

Suddenly, he realised there was someone beside him.

"Oh," he said, gruffly, his eye clocking the crutches. "How are you?"

I felt I had to explain: "As you ask, Prime Minister, I've just had my second knee ligament replacement operation which led to a deep vein thrombosis and this morning I had two emergency drilling sessions to relieve some of the pressure caused by a dreadfully infected tooth root."

"Oh," he said.

There followed an awkward silence. We both knew the conversational ball was definitely in his side of the court, but he didn't know how to respond.

Eventually, he blurted out: "I hope we can help."

That was it. No question about how I came by my knee injuries, no conventional response to dental pain stories such as "There's nothing worse..."

He then launched into a long stream of very informed and thoughtful comments about the state of the Redcar steel industry and the regional economy, which came to an end as the car reached Durham station, and he tried to flee without fully undoing his seatbelt.

It was no surprise when a few weeks later the British voters were unable to warm to the man who couldn't empathise with excruciating dental pain.