Common risk factor approach to address socioeconomic inequality in the oral health of preschool children--a prospective cohort study.

BACKGROUND: Dental caries remains the most prevalent chronic condition in children and a major contributor to poor general health. There is ample evidence of a skewed distribution of oral health, with a small proportion of children in the population bearing the majority of the burden of the disease. This minority group is comprised disproportionately of socioeconomically disadvantaged children. An in-depth longitudinal study is needed to better understand the determinants of child oral health, in order to support effective evidence-based policies and interventions in improving child oral health. The aim of the Study of Mothers' and Infants' Life Events Affecting Oral Health (SMILE) project is to identify and evaluate the relative importance and timing of critical factors that shape the oral health of young children and then to seek to evaluate those factors in their inter-relationship with socioeconomic influences. METHODS/DESIGN: This investigation will apply an observational prospective study design to a cohort of socioeconomically-diverse South Australian newborns and their mothers, intensively following these dyads as the children grow to toddler age. Mothers of newborn children will be invited to participate in the study in the early post-partum period. At enrolment, data will be collected on parental socioeconomic status, mothers' general and dental health conditions, details of the pregnancy, infant feeding practice and parental health behaviours and practices. Data on diet and feeding practices, oral health behaviours and practices, and dental visiting patterns will be collected at 3, 6, 12 and 24 months of age. When children turn 24-30 months, the children and their mothers/primary care givers will be invited to an oral examination to record oral health status. Anthropometric assessment will also be conducted. DISCUSSION: This prospective cohort study will examine a wide range of determinants influencing child oral health and related general conditions such as overweight. It will lead to the evaluation of the inter-relationship among main influences and their relative effect on child oral health. The study findings will provide high level evidence of pathways through which socio-environmental factors impact child oral health. It will also provide an opportunity to examine the relationship between oral health and childhood overweight.

Chapter 8: Milk, Yoghurts and Dental Caries.

Milk is an important part of the human diet; after weaning, cow's milk (bovine milk) predominates and this chapter considers the effect of bovine milk on dental caries. Yoghurt, which is a milk product, is also considered here. Several published reviews have concluded that milk is of very low cariogenicity and may have some caries protective potential. For example, WHO reviewed the strength of the evidence in 2003 and concluded that a "decreased risk" of dental caries from milk was "possible." The evidence comes from several types of study: epidemiological studies (interventional and observational), animal experiments, plaque pH studies, and in vivo and in vitro enamel and dentine slab experiments. More recent observational epidemiological studies have adjusted for potential confounders and have reported that milk consumption is associated with lower caries experience or incidence. Other types of study generally support this conclusion. Reasons for these favourable caries-related properties include the lower acidogenicity of lactose compared with other dietary sugars and the protective effects of calcium, phosphate, proteins, and fats. There is less research concerning yoghurts but it is likely that the cariogenic potential of plain yoghurt is similar to that of milk. The addition of sucrose to milk increases caries risk.

Caries prevention through the fluoridation of milk. A review.

The aim of this review is to give an overview of 50 years experience of milk fluoridation and draw conclusions about the applicability of the method. Fluoridated milk was first investigated in the early 1950s, almost simultaneously in Switzerland, the USA and Japan. Stimulated by the favourable results obtained from these early studies, the establishment of The Borrow Dental Milk Foundation (subsequently The Borrow Foundation) in England gave an excellent opportunity for further research, both clinical and non-clinical, and a productive collaboration with the World Health Organization from the early 1980s onwards. Numerous peer-reviewed publications in international journals showed clearly the bioavailability of fluoride in milk, and increased concentrations of fluoride in saliva, dental plaque, dental enamel and dentine, and urine, after consumption of fluoridated milk. Clinical trials were initiated in the 1980s--some of these can be classed as randomised controlled trials, while most of the clinical studies were community preventive programs. These evaluations showed clearly that the optimal daily intake of fluoride in milk is effective in preventing dental caries. At present, milk fluoridation programs are running continuously in about ten countries of the world. Fluoridation of milk can be recommended as a caries preventive measure where the fluoride concentration in drinking water is suboptimal, caries experience in children is significant, and there is an existing school milk program. The program should aim to provide fluoridated milk for at least 200 days per year and should commence before the children are 4 years of age.

Effectiveness of water fluoridation in caries prevention.

OBJECTIVES: To review the effectiveness of adjusted fluoridation of public water supplies in the prevention of dental caries, with emphasis on results of studies published worldwide since 1990 and to discuss aspects of the design and reporting of these studies compared with those published before 1990. METHOD: Studies published worldwide, in any language, reporting the effect of water fluoridation in terms of the dmf/DMF caries index between 1990 and 2010 were examined. The literature search was by professional Internet search, back-tracking from references given in publications, hand-searching all issues of four journals and by contacting colleagues in relevant countries. For the dmf index, age 5 year was preferred, and for the DMF index, age 12 year or older was preferred. The results were compared with results obtained from worldwide literature search prior to 1990 by the same author. RESULTS: Fifty-nine studies of adjusted water fluoridation were identified, yielding 83 evaluations (30 recording dmft/s and 53 recording DMFT/S) from 10 countries. These numbers are lower than pre-1990 results of 113 studies (66 for primary and 86 for permanent teeth) from 23 countries. For the USA, for example, four studies were identified since 1990 compared with 61 studies before 1990. The most number of recent reports came from Brazil and Australia. There were fewer reports of per cent caries reductions (% CR) above 50% in the recent studies. 86% of the post-1990 investigations were concurrent control cross-sectional studies and, of these, 52% used multivariate statistical analysis to adjust for confounding factors. In the eight studies that provided dmf/DMF data before and after adjustment for confounders, the % CR were little affected by these adjustments. CONCLUSIONS: Fewer studies have been published recently. More of these have investigated effect at the multi-community, state or even national level. The dmf/DMF index remains the most widely used measure of effect. % CR were lower in recent studies, and the 'halo' effect was discussed frequently. Nevertheless, reductions were still substantial. Statistical control for confounding factors is now routine, although the effect on per cent reductions tended to be small. Further thought is needed about the purpose of evaluation and whether measures of effect and study design are appropriate for that purpose.

The relationship between acid-etch patterns and bond survival in vivo.

The aim of this study was to investigate the relationship between acid-etch quality and bond survival in vivo. The subjects were 29 orthodontic patients. High-resolution silicone impressions were taken of the buccal tooth surfaces after etching for 30 seconds with 37% phosphoric acid. The impressions were replicated in epoxy resin and examined under high magnification in a scanning electron microscope. A 4-point classification system and histometric techniques were used to evaluate etch patterns on the enamel surfaces where orthodontic brackets were to be bonded. After impressions were made, all teeth (including first molars) were bonded with 0.022-in Andrews' prescription brackets ("A" Company, San Diego, Calif) and Right-On composite (TP Orthodontics, Leeds, England). The first date of bond failure for each tooth was recorded; it varied from 1 to 806 days. An ideal etch pattern was found on less than 5% of the orthodontic bonding area; type C pattern (pitted enamel surface) occupied the greatest area. Overall, the failure rate was 55.8% over 26 months; the greatest failure rate occurred in first molars. Multiple regression analysis revealed a positive and statistically significant relationship between the area occupied by ideal etch type and the length of survival of the bond (P <.001).