Nearly two-thirds of patients ignore dentists' advice about cleaning their teeth, according to North-East researchers.

Despite the best efforts of dentists, only about one-third of gum disease patients followed the advice they were given on how long to brush their teeth.

And those who did not follow advice still believed they were brushing for longer than they were, which has major implications for dentists wishing to change patients' behaviour.

Gum disease can eventually lead to multiple tooth loss, but in many cases damage can be stabilised or reversed if treatment is combined with a good brushing regime.

During the study, which was led by researchers at Newcastle University and published in the British Dental Journal, patients were given advice on how to brush their teeth. They were told to brush twice a day for two minutes each time.

Each of the 17 study participants used an electric toothbrush that recorded brushing time.

The participants were also asked to fill in diaries detailing their brushing habits over the course of the eight-month study.

When the researchers analysed the data from the electronic toothbrushes, they found that only about a third of people followed the advice, even though the diaries suggested that more than half of patients thought they had been compliant.

Dr Giles McCracken, of the university's school of dental sciences, said: "Patients must understand their health is mainly their responsibility, and if they are not going to comply with the advice of health providers like dentists, who have their best interests at heart, they must accept the consequences."