Children from deprived areas are much more likely to have signs of tooth decay, official figures show.
There is concern about decay rates
Office for National Statistics data compared children attending schools classified as deprived and non-deprived.
At deprived schools, 60% of five-year-olds and 70% of eight year-olds showed obvious decay in their milk teeth.
At non-deprived schools the figures were 40% for five-year-olds and 55% for eight-year-olds.
In permanent teeth, 55% of 12-year-olds and 72% of 15-year-olds attending deprived schools had experience of obvious decay, compared with 42% of 12-year-olds and 55% of 15-year-olds in non-deprived schools.
The survey also threw up other evidence of a relationship between socio-economic status and tooth decay.
For example, a lower proportion of five-year-olds (34%) from managerial and professional occupational groups had decay than five-year-olds from routine and manual occupational groups (53%).
For 15-year-olds, the figures were 47% for managerial and professional occupational groups, and 65% for routine and manual occupational groups.
Although few children had lost teeth due to decay, more 15-year-olds from routine and manual occupational groups (7%) had teeth extracted because of decay than 15-year-olds from managerial and professional occupational groups (2%).
A larger proportion (25%) of 15-year-olds in deprived schools also had unmet orthodontic treatment needs compared with those in non-deprived schools (21%).
Unmet orthodontic treatment need was twice as high (26%) among 15-year-olds from routine and manual family backgrounds compared with those from managerial and professional family backgrounds (13%).
The figures come from a re-analysis of data contained in the 2003 Children's Dental Health Survey, first published in July.
It also shows that more children are visiting the dentist at an earlier age than ever.
The proportion of five and eight-year-olds making their first visit to the dentist before the age of two has more than doubled since 1993.
In 1983, 7% of five-year-olds' parents reported that their children visited their dentist before the age of two. This increased to 15% in 1993 and 31% in 2003.
Among eight-year-olds, 6% made early visits in 1983. This doubled to 12% in 1993, and increased to 33% in 2003.
The proportion of five-year-olds reported to have never visited the dentist decreased from 14% in 1983 to 10% in 1993 to 6% in 2003.
Around a fifth of parents of five and eight-year-olds, and around a quarter of parents of 12 and 15-year-olds, reported having difficulties accessing an NHS dentist willing to treat their child.
British Dental Association spokesperson said: "It is very encouraging that parents are taking their children to the dentists earlier now than they were 20 years ago, the benefits of which certainly appear to be borne out by the improvement in dental health of teenagers.
"However, the BDA remains concerned about the poorer dental health of children from deprived backgrounds.
"The BDA is also concerned that some children are unable to access dental care. The severe shortage of dentists in the UK - which the government puts at around 1,850 in England alone - means that many dentists are working to capacity, leading to the access issues outlined in this report."
A Department of Health spokesperson stressed that oral health was improving, and that dental decay for 12 and 15-year-olds was at lowest levels since records began.
"Twelve year-old children in England now have the best dental health of their age in Europe.
"However, poor dental health is still too closely linked to deprivation. We are determined to reduce inequalities in oral health and announced in July that we are investing an extra £368m in NHS Dentistry, recruiting 1,000 more NHS dentists in little over a year and reforming the dental system to improve the long-term oral health of the nation."
Schools where 30% or more children were eligible for free school meals were categorised as deprived.