The problem may be exacerbated by a failure of residential and nursing homes to ensure residents receive proper basic dental care.

Researchers found high rates of tooth decay and other diseases of the mouth in a study of people living in residential and nursing homes in West Hertfordshire.

Writing in The Lancet medical journal, they say these problems may contribute to eating problems and low nutrient and vitamin C levels found in the study group.

Debra Simons and colleagues from West Hertfordshire Community Dental Services and King's College London randomly selected 55 of the 110 residential and nursing homes in West Hertfordshire. They recorded details of the oral health and past dental care of 249 elderly men and 792 women.

Dentures can lead to oral health problems

They found high levels of dental caries (tooth decay) and plaque retention, and poor denture care leading to inflammation and soreness of the mouth.

Among those in the study, 250 had difficulty eating, 206 had problems with taste, and 261 found it hard to care for their mouths.

In addition, 343 people needed assistance in cleaning their teeth and dentures, but only 94 reported that the staff had helped them.

The managers and deputy managers of the homes indicated that there was no systematic approach to arranging dental care.

Dental help was only sought when residents or their relatives complained of acute problems such as pain or a broken denture.

The researchers say the poor dental health coupled with a reduced ability to communicate, typical among elderly people may cause weight loss, dehydration, and debility.

"It is surely a disgrace that the mouth, one of the most personal and intimate areas of the body, should be neglected in such a manner," they conclude.