Just over half of all adults in Scotland are not registered with an NHS dentist, figures have shown.
There has been little progress in dental cover
The number of children registered fell by 10,000 over the course of a year and the number of adults by 23,000.
Population changes mean the proportion of people signed up with a dentist was virtually unchanged.
The Scottish Executive admitted the lack of progress was "disappointing" and the Scottish National Party (SNP) blamed a shortage of dental staff.
A total of 716,070 children (66%) were signed up to NHS general dentists in March 2004, compared with 725,494 last year.
The number of adults registered fell from 1,959,293 to 1,935,634, or 49%.
The executive welcomed a rise in the relatively small proportion of Scots registered with salaried NHS general dentists, those directly and exclusively employed by health boards.
This reflects the increase in dentists employed by health boards in a bid to meet acute shortages of self-employed high street dentists willing to continue taking on NHS work.
An executive spokesman said: "We are disappointed that levels of adults and, in particular, children registered within the general dental services has not increased.
"We have pledged to systematically introduce by 2007 free dental checks for all as announced in the coalition partnership agreement."
SNP health spokeswoman Shona Robison said: "Since 2000 the number of adults registering with a dentist has dropped by over 36,000 and the number of children has also dropped by over
"My concern is that if adults are unable to register, this will have a knock-on effect on the number of children who will receive professional dental care.
"The executive has already set targets to reduce the number of five-year-olds in Scotland suffering from tooth decay but they have been unable to make progress, and with such a staffing crisis in the dental profession it is difficult to see how they will in the near future."