Dundee Dental Hospital was forced to close yesterday after a sterilisation failure.

Patients were turned away from the medical facility and NHS Tayside said the problem was caused by the breakdown of equipment.

The failure meant appointments for 276 patients were cancelled. They will be offered rescheduled appointments as soon as possible, said the health board.

Some patients were not aware of the issue and turned up to be told they could not be seen. Dozens of people were asked to leave the building around 10am and its doors were closed.

One patient said: "I had an appointment at 10.15am. I got there early and, about 10, a woman came in and told us that we all had to leave. She had no explanation at all."

A spokeswoman for NHS Tayside said by 4pm yesterday the issues had finally been resolved and the faulty sterilising equipment repaired.

"There are a whole lot of stages in the decontamination process for instruments and there had been a breakdown in the equipment in one part of that," she said. "It just meant there were no sterilised instruments to do any work.

"But the hospital will be working as normal on Monday. Emergencies were dealt with as normal. They were triaged immediately by the consultant and they would be dealt with there and then, or sent to Ninewells Hospital."

Caroline Selkirk, NHS Tayside executive director, said: "We apologise for any inconvenience this unforeseen problem has caused patients."

Waiting times at the dental hospital rose from 10 weeks in 1999 to 19 weeks in 2005, while the wait for oral surgery had risen from nine weeks in 1999 to 15 weeks in 2005.