The Cochrane Review on water fluoridation for the prevention of dental caries was published in 2015 and attracted considerable interest and comment, especially in countries with extensive water fluoridation programmes. The Review had two objectives: (i) to evaluate the effects of water fluoridation (artificial or natural) on the prevention of dental caries, and (ii) to evaluate the effects of water fluoridation (artificial or natural) on dental fluorosis. The authors concluded, inter alia, that there was very little contemporary evidence, meeting the Review's inclusion criteria, that evaluated the effectiveness of water fluoridation for the prevention of dental caries. The purpose of this critique is to examine the conduct of the above Review, and to put it into context in the wider body of evidence regarding the effectiveness of water fluoridation. While the overall conclusion that water fluoridation is effective in caries prevention agrees with previous reviews, many important public health questions could not be answered by the Review because of the restrictive criteria used to judge adequacy of study design and risk of bias. The potential benefits of using wider criteria in order to achieve a fuller understanding of the effectiveness of water fluoridation are discussed.

Tooth decay rates among children have been falling in most European countries since the mid-1970s, with the gap between the countries with the highest and lowest average levels narrowing. Widespread use of fluoride toothpaste, high levels of educational achievement in the Scandinavian countries, and public health approaches such as the use of fluoridated salt in Switzerland, France and Germany, have all contributed to this welcome improvement. Whilst average tooth decay rates are down, those averages mask stubbornly high decay rates in some communities and in some social groups. Many young children in the UK still suffer from severe dental caries (BASCD, 2007). No one in public health could reasonably argue that dental caries in the UK is a battle already won. It is not. Even if we take the deceptively soothing average dmft scores (decayed, missing or filled teeth), we find a fivefold difference between the best and worst dental health. The average South Staffordshire five year old has 0.6 dmf teeth (the best dental health in England), while the average Blackburn five year old has 3.2 dmf teeth (the worst in England) (BASCD, 2007).

Objective To investigate the socio-demographic profile of patients using the Leeds Community Dental Service (CDS) in 1996/97 and to determine any changes in profile since 1991/92. Design Retrospective. Setting The area served by Leeds Health Authority. Subjects A total of 8,051 patients who had used the Leeds CDS in 1996/97 together with 9,372 patients from 1991/92. Outcome measures Socio-demographic profile, including age group; ethnicity; deprivation (Townsend index) and disability. Results Of children under 16 years old using the CDS in 1996/97, 24% were of South Asian ethnic origin, much higher than the 6% reported for Leeds in the 1991 census. Over the period of the study there was a reduction in the: proportion of patients aged 5-15 years (75% to 65%, P < 0.001) and an increase in those aged 16-64 years (13% to 19%, P < 0.001). Increases were also seen in the proportion of patients from districts in the two most deprived quintiles (60% to 67%, P < 0.001) and for patients with special needs (19% to 28%, P < 0.001). Conclusions This study indicated an increased emphasis by the CDS on targeting groups likely to be unable or unwilling to seek treatment from the GDS. Socio-demographic profiling can be useful in monitoring the progress of changes in primary dental care.

OBJECTIVE:To investigate the relationship between material deprivation, ethnicity, dental health and related behaviour in the five-year-old population of Leeds.DESIGN:Analytical survey using a stratified cluster sample of primary schools and a questionnaire to parents. Children were assigned to one of five bands according to the ranking of the Townsend deprivation index for the census enumeration district in which they lived. Standard clinical criteria were used.SETTING:Clinical examinations were carried out in school by four trained and calibrated examiners.PARTICIPANTS:Two thousand six hundred and seventy seven children were examined and 1881 parental questionnaires were returned (70 per cent response).OUTCOME MEASURES:Caries experience expressed as mean dmft.RESULTS:Caries experience increased significantly with deprivation. Deprivation gradients were found in reported dental visiting, parental dental attendance and use of the Community Dental Service. Differences in caries experience between ethnic groups were independent of deprivation score with Asian children from the most deprived districts having a higher mean dmft than their white Caucasian and Afro-Caribbean counterparts (4.80, 3.21, 2.00; P < 0.001). Muslim Asians had significantly higher (P < 0.001) caries experience (dmft = 4.63) than non-Muslim Asians (dmft = 2.08) and the difference was maintained when the effect of deprivation was controlled (P < 0.05).CONCLUSIONS:The Townsend index is a useful indicator of dental health and related behaviour among populations but does not explain variations between ethnic groups.

Non-response bias is a potentially serious problem in studies involving human subjects. A parental questionnaire/negative consent form was used in a dental epidemiological survey of 5-year-old children in Leeds. The aim of this study was to determine whether and to what extent there was any variation in caries experience and oral cleanliness between responding and non-responding groups. 6,494 children were examined and completed questionnaires were returned for 4,069 (63 per cent). The response was higher for white children (65 per cent) than for Asian (39 per cent) and Afro-Caribbean children (45 per cent). Lower response rates were found from parents living in inner city areas associated with social deprivation. Children of non-responders had poorer oral cleanliness and higher caries experience (mean dmft). This study demonstrated that members of a non-response group are likely to be substantially different from responders.