Mary Hedges, who uses a wheelchair, was unable to get into Daventry Dental Practice because officials have refused to let the owners install disabled access at its Grade II listed building.
The pensioner was forced to let her dentist check her teeth on the pavement outside, in the busy Market Square in Daventry, and said she had to put up with toothache because she could not be treated properly.
Mrs Hedges, from Woodford Halse, said: "It was very embarrassing, and I was really angry about it. There were a lot of people walking past when the doctor checked my teeth, but he was only doing his best in a bad situation.
"The work's only half done now because he couldn't do a proper job in the street. I've got a bit of pain in my teeth, but it's not too bad and I'm just going to put up with it now."
On the same day last week Susan Smith took her two-year-old daughter Ruby Bowyer, who suffers from cystic fibrosis, to the dentist, only to be faced with an impossible climb up the stairs.
Dr Resh Diu, of Daventry Dental Practice, said every effort had been made to try to improve patient access. He said: "Conservation officers need to live a little more in the real world.
"We looked at putting in a ramp for the front steps but that would be too long. We asked about a stairlift but that would involve altering the door.
"We even offered to put in a handrail that we could remove when we leave, but because it would alter the appearance of the building we weren't allowed."
Daventry District Council's manager of environmental protection, Tony Gillet, said: "By law it is up to service providers to ensure their services are fully accessible. Historic buildings should not be altered where that would harm their character."
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The full article contains 388 words and appears in Northampton Chron & Echo newspaper.