Doctors and dentists will be told today that there is no case for routine removal of wisdom teeth without symptoms of infection or disease.

In its first full report, the National Institute for Clinical Excellence (Nice, the government body appointed last year to monitor the effectiveness of National Health Service treatment), is expected to say the routine removal of healthy teeth is worthless. It is likely to back existing British Dental Association and Royal College of Surgeons guidance that treatment should be restricted to patients whose teeth show signs of disease, while those with impacted wisdom teeth - lying crookedly - should be monitored.

About 50,000 patients a year have wisdom teeth removed at a cost of £15m-£20m, according to the British Dental Association. A survey in 1997-98 by the faculty of dental surgery of the Royal College of Surgeons showed one in five wisdom teeth removed was healthy.

The Nice report is its first full investigation into a treatment and marks the start of a rolling programme which will see publication of two reports a month. Doctors and dentists will be expected to follow the guidelines in the reports or be prepared to justify themselves.

Nice is seen as a key plank of government efforts to reform the NHS by spreading good practice and ending outmoded treatment. Guidelines on hip replacements, coronary stents (devices for holding arteries open) and the use of the drug Taxol in treating breast and ovarian cancer are expected by the end of next month.

But the wisdom-teeth report is likely to be less controversial than Nice's early interim guidance, in the autumn, on the anti-flu drug Relenza, which advised against its use on the NHS, angering Glaxo Wellcome, its maker. Nice is to revisit the issue of anti-flu drugs for a full report later this year.

Nice's recommendations on wisdom teeth are likely to be accepted by dentists and oral surgeons, who will say they are already being followed. In the late Eighties and early Nineties dentists and surgeons removed healthy impacted wisdom teeth from thousands of patients in the belief it would prevent infection. Between 1988 and 1994 the number removed rose by one-third and 150,000 patients a year had surgery, which often required a general anaesthetic and a stay in hospital, and could cause"lock jaw" during recovery.

Advice changed in the mid-Nineties as dental surgeons recognised the risks of operating outweighed the risks of leaving the teeth. Latest figures show 50,000 patients a year are treated and the proportion of healthy teeth removed dropped from 40 per cent in 1994-95 to 20 per cent in 1997-98.