Scoping Review of Oral Health-Related Birth Cohort Studies: Toward a Global Consortium.

The multidisciplinary nature and long duration of birth cohort studies allow investigation of the relationship between general and oral health and indicate the most appropriate stages in life to intervene. To date, the worldwide distribution of oral health-related birth cohort studies (OHRBCSs) has not been mapped, and a synthesis of information on methodological characteristics and outcomes is not available. We mapped published literature on OHRBCSs, describing their oral health-related data and methodological aspects. A 3-step search strategy was adopted to identify published studies using PubMed, Embase, Web of Science, and OVID databases. Studies with baseline data collection during pregnancy or within the first year of life or linked future oral health data to exposures during either of these 2 life stages were included. Studies examining only mothers' oral health and specific populations were excluded. In total, 1,721 articles were suitable for initial screening of titles and abstracts, and 528 articles were included in the review, identifying 120 unique OHRBCSs from 34 countries in all continents. The review comprised literature from the mid-1940s to the 21st century. Fifty-four percent of the OHRBCSs started from 2000 onward, and 75% of the cohorts were from high-income and only 2 from low-income countries. The participation rate between the baseline and the last oral health follow-up varied between 7% and 93%. Ten cohorts that included interventions were mostly from 2000 and with fewer than 1,000 participants. Seven data-linkage cohorts focused mostly on upstream characteristics and biological aspects. The most frequent clinical assessment was dental caries, widely presented as decayed, missing, and filled teeth (DMFT/dmft). Periodontal conditions were primarily applied as isolated outcomes or as part of a classification system. Socioeconomic classification, ethnicity, and country- or language-specific assessment tools varied across countries. Harmonizing definitions will allow combining data from different studies, adding considerable strength to data analyses; this will be facilitated by forming a global consortium.

Oral Health Birth Cohort Studies: Achievements, Challenges, and Potential.

Birth cohorts are those among observational studies that provide understanding of the natural history and causality of diseases since early in life. Discussions during an International Association for Dental Research symposium in London, United Kingdom, in 2018, followed by a workshop in Bangkok, Thailand, in 2019, concluded that there are few birth cohort studies that consider oral health and that a broader discussion on similarities and differences among those studies would be valuable. This article aims to 1) bring together available long-term data of oral health birth cohort studies from the low, middle, and high-income countries worldwide and 2) describe similarities and differences among these studies. This work comprises 15 studies from all 5 continents. The most studied dental conditions and exposures are identified; findings are summarized; and methodological differences and similarities among studies are presented. Methodological strengths and weaknesses are also highlighted. Findings are summarized in 1) the negative impact of detrimental socioeconomic status on oral health changes over time, 2) the role of unfavorable patterns of dental visiting on oral health, 3) associations between general and oral health, 4) nutritional and dietary effects on oral health, and 5) intergenerational influences on oral health. Dental caries and dental visiting patterns have been recorded in all studies. Sources of fluoride exposure have been documented in most of the more recent studies. Despite some methodological differences in the way that the exposures and outcomes were measured, some findings are consistent. Predictive models have been used with caries risk tools, periodontitis occurrence, and permanent dentition orthodontic treatment need. The next steps of the group's work are as follows: 1) establishing a consortium of oral health birth cohort studies, 2) conducting a scoping review, 3) exploring opportunities for pooled data analyses to answer pressing research questions, and 4) promoting and enabling the development of the next generation of oral health researchers.

Fluoride Revolution and Dental Caries: Evolution of Policies for Global Use.

Epidemiological studies over 70 y ago provided the basis for the use of fluoride in caries prevention. They revealed the clear relation between water fluoride concentration, and therefore fluoride exposure, and prevalence and severity of dental fluorosis and dental caries. After successful trials, programs for water fluoridation were introduced, and industry developed effective fluoride-containing toothpastes and other fluoride vehicles. Reductions in caries experience were recorded in many countries, attributable to the widespread use of fluoride. This is a considerable success story; oral health for many was radically improved. While previously, water had been the only significant source of fluoride, now there are many, and this led to an increase in the occurrence of dental fluorosis. Risks identified for dental fluorosis were ingestion of fluoride-containing toothpaste, water fluoridation, fluoride tablets (which were sometimes ingested in areas with water fluoridation), and infant formula feeds. Policies were introduced to reduce excessive fluoride exposure during the period of tooth development, and these were successful in reducing dental fluorosis without compromising caries prevention. There is now a much better understanding of the public perception of dental fluorosis, with mild fluorosis being of no aesthetic concern. The advantages of water fluoridation are that it provides substantial lifelong caries prevention, is economic, and reduces health inequalities: it reaches a substantial number of people worldwide. Fluoride-containing toothpastes are by far the most important way of delivering the beneficial effect of fluoride worldwide. The preventive effects of conjoint exposure (e.g., use of fluoride toothpaste in a fluoridated area) are additive. The World Health Organization has informed member states of the benefits of the appropriate use of fluoride. Many countries have policies to maximize the benefits of fluoride, but many have yet to do so.

Fluoridated Water Modifies the Effect of Breastfeeding on Dental Caries.

Breastfeeding is important for health and development. Yet, the interaction between breastfeeding duration and usage of fluoridated water on caries experience has not been investigated. This study examined exposure to fluoridation as an effect modifier of the association between breastfeeding duration and caries. The 2012 to 2014 national population-based study of Australian children involved parental questionnaires and oral epidemiological assessment. Children were grouped by parent-reported breastfeeding duration into minimal (none or <1 mo), breastfed for 1 to <6 mo, breastfed for 6 to 24 mo, and sustained (>24 mo). Residential history and main water source used for the first 2 y of life were collected to group children into exposed (WF) and nonexposed (NF) to fluoridation. Socioeconomic status, infant formula feeding, and sugar-sweetened beverage (SSB) consumption data were collected. The prevalence and severity of caries in children aged 5 to 6 y were primary outcomes. Multivariable regression models with robust error estimation were generated to compute prevalence ratios (PRs) and mean ratios (MRs) for 3 breastfeeding groups against the reference (breastfed for 6-24 mo). Of the 5- to 6-y-old children, 2,721 were in the WF and 1,737 were in the NF groups. The groups had comparable distributions of socioeconomic factors, infant formula feeding, and SSB consumption. There were U-shape distributions of caries experience among breastfeeding groups, being more pronounced among NF children. Among NF children, the minimal and sustained breastfeeding groups had significantly higher PR (1.4 [1.1-1.9] and 1.8 [1.4-2.4]) and MR (2.1 [1.4-3.3] and 2.4 [1.4-4.1]) than the reference group. However, among the WF children, this association between breastfeeding duration and caries attenuated after adjustment for other factors. The study contributes evidence of a nonlinear (U-shape) association between breastfeeding duration and dental caries. Early life exposure to fluoridated drinking water attenuated the potential cariogenic effect of both lack of and sustained breastfeeding.

Fluoride and Oral Health.

The discovery during the first half of the 20th century of the link between natural fluoride, adjusted fluoride levels in drinking water and reduced dental caries prevalence proved to be a stimulus for worldwide on-going research into the role of fluoride in improving oral health. Epidemiological studies of fluoridation programmes have confirmed their safety and their effectiveness in controlling dental caries. Major advances in our knowledge of how fluoride impacts the caries process have led to the development, assessment of effectiveness and promotion of other fluoride vehicles including salt, milk, tablets, toothpaste, gels and varnishes. In 1993, the World Health Organization convened an Expert Committee to provide authoritative information on the role of fluorides in the promotion of oral health throughout the world (WHO TRS 846, 1994). This present publication is a revision of the original 1994 document, again using the expertise of researchers from the extensive fields of knowledge required to successfully implement complex interventions such as the use of fluorides to improve dental and oral health. Financial support for research into the development of these new fluoride strategies has come from many sources including government health departments as well as international and national grant agencies. In addition, the unique role which industry has played in the development, formulation, assessment of effectiveness and promotion of the various fluoride vehicles and strategies is noteworthy. This updated version of 'Fluoride and Oral Health' has adopted an evidence-based approach to its commentary on the different fluoride vehicles and strategies and also to its recommendations. In this regard, full account is taken of the many recent systematic reviews published in peer reviewed literature.

Critique of the review of 'Water fluoridation for the prevention of dental caries' published by the Cochrane Collaboration in 2015.

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.

Sugars consumption by 379 11-12-year-old English children in 1990 compared with results in 1980.

The amount of sugars consumed by young adolescents was assessed in 1990 using the same methods as those employed in a similar survey in 1980. The children were the same age (mean 11 years 6 months) and from the same seven schools in both survey. In 1980, 405 children completed the study and 379 in 1990. Information was collected using two 3-day dietary diaries, each child being interviewed by a dietitian upon completion of a diary. The dietitian in this study was calibrated closely with the dietitian who undertook the 1980 study so as to ensure comparable diet evaluation methods. Total sugars consumption was unchanged (117 g/day in 1980, 118 g/day in 1990) but consumption of non-milk extrinsic sugars increased (83 g/day in 1980, 90 g/day in 1990) and milk and intrinsic sugars decreased (34 g/day in 1980, 28 g/day in 1990) between the two surveys. In 1990, non-milk extrinsic sugars contributed 17% to total dietary energy intake, while milk and intrinsic sugars contributed 5%. There was little difference in percent contributions between the sexes, but some social-class trends were apparent. Confectionery provided 33% and soft drinks provided 27% of non-milk extrinsic sugars, these two dietary sources providing 60% of non-milk extrinsic or 46% of total sugars intake. These levels of consumption are considerably higher than those currently recommended in the UK.

Changes in consumption of sugars by English adolescents over 20 years.

OBJECTIVE: Dietary surveys of 11- to 12-year-old Northumbrian children in 1980 and 1990 revealed that consumption of non-milk extrinsic sugars (NMES) was 16-17% of energy intake. This study reports dietary sugars consumption in 2000 and compares it with data collected in 1980 and 1990, using identical methods. DESIGN: A repeat cross-sectional dietary survey of children aged 1-12 years attending the same schools as in the 1980 and 1990 surveys. SETTING: Seven middle schools in south Northumberland. SUBJECTS: All children aged 11-12 years old attending the seven schools. METHOD: Food consumption was recorded using two 3-day diet diaries. Food composition tables were used to calculate energy and nutrient intakes. NMES, and milk and intrinsic sugars were calculated using previously described methods. RESULTS: The numbers of children completing the surveys in 1980, 1990 and 2000 were 405, 379 and 424, respectively; approximately 60-70% of eligible children. Total sugars provided 22% of energy consistently over the three surveys. NMES consumption in 2000 provided 16% of energy compared with 16% in 1980 and 17% in 1990. Sources of NMES changed over the three surveys. NMES from soft drinks doubled from 15 to 31 g day(-1), and from breakfast cereals increased from 2 to 7 g day(-1) over the 20 years. Confectionery and soft drinks provided 61% of NMES. Over 20 years, the proportion of energy from fat decreased by 5% and from starch increased by 4%, creating a welcome tilt in the fat-starch see-saw, without an adverse effect on sugars intake. CONCLUSIONS: Consumption of NMES in 2000 was substantially higher than recommended, and there has been little change over 20 years. Continued and coordinated efforts are required at a national, community and individual level to reduce the intake of NMES.

Changes over 20 years in macronutrient intake and body mass index in 11- to 12-year-old adolescents living in Northumberland.

Monitoring adolescent diets over time enables the assessment of the effectiveness of public health messages which are particularly important in vulnerable groups such as adolescents. In 2000, 424 children aged 11-12 years old completed two 3 d estimated dietary records. On the fourth day one nutritionist interviewed each child to clarify the information in the diary and foods were quantified with the aid of food models. Nutrient intake was calculated using computerised food tables. These children attended the same seven schools in the same Northumberland area as the 11- to 12-year-old children who recorded their diet using the same method in 1980 (n 405) and 1990 (n 379), respectively. Height and weight, and parental occupation were recorded in all three surveys for each child. Height and weight were used to calculate BMI, weight was used to estimate BMR and parental occupation was used to determine social class. Comparing the macronutrient intakes in 2000 with 1980 and 1990, energy intakes (EI) fell in boys (to 8.45 MJ) and girls (to 7.60 MJ). This fall may, at least in part, be due to an increase in low energy reporting. For 1980, 1990 and 2000 the percentage of boys with EI:BMR below 1.1 was 6, 15 and 23 %, respectively; for girls, 3, 14 and 18 %, respectively. Percentage energy from fat was unchanged between 1980 and 1990 but fell to 35 % (about 76 g/d) in 2000, alongside a 3 % increase in percentage energy from starch (30 %). Percentage energy from non-milk extrinsic sugars remained above recommendations (16 %; about 82 g/d). The number of overweight and obese children increased from 11 % to 30 % between 1980 and 2000. Positive changes have occurred in the Northumbrian adolescent diet but social inequalities, reported in previous surveys, remain.

Changes in water intake of Northumbrian adolescents 1980 to 2000.

OBJECTIVES: To determine: total water intake in young English adolescents; the relative importance of sources of water intake; and changes in water intake and sources of water between 1980 and 2000. DESIGN: A cross-sectional observational study of the diets of 11-12-year-old children attending seven schools in south Northumberland, UK. The information obtained was compared with results from a similar survey carried out 20 years previously. METHODS: All children attending these schools were invited to participate. They completed a three-day diet diary with an interview on the fourth day, on two occasions during the school year. Standard UK food composition tables were used and water intake from various sources calculated. Anthropometric and social class information was obtained. RESULTS: Four hundred and twenty-four children completed all aspects of the study (64% of those eligible). The mean total water intake was 1,130 g d(-1), approximately the same as that recorded 20 years before. Water intake in relation to energy intake: water intake was 139 g MJ(-1) in boys and 143 g MJ(-1) in girls. Sixty-five per cent of water came from drinks and 35% from foods; very similar to proportions 20 years before. The sources of water in drinks had changed considerably, with a marked increase in consumption of soft drinks (especially carbonated drinks) and a decrease in consumption of hot drinks and milk. There were a few differences between sexes but little difference between social groups. CONCLUSIONS: Total water intake was similar to that recorded 20 years previously and lower than intakes reported in other countries. Changes in the sources of water meant that less water consumed was likely to come from the tap in the house and more from drinks made elsewhere, than 20 years previously. These changes have implications for estimating fluoride intake in fluoridated areas.

Review of methods used to estimate non-milk extrinsic sugars.

BACKGROUND: Those sugars in foods, which are potentially damaging to dental health, were classified by the Committee on Medical Aspects of Food Policy (COMA) as non-milk extrinsic sugars (NMES). The NMES include sugars outside the cellular structure of a food, excluding the sugars naturally present in milk and milk products. The NMES should contribute no more than 10% of energy intake (Department of Health, 1991). A number of studies have been published where NMES content of foods has been estimated. The purpose of this study was to carry out a comprehensive literature review using a methodical search strategy in order to identify the different methods that have been used for NMES estimation. METHODS: Databases searched were MEDLINE, EMBASE, Health-CD and Health Management Information Consortium (HMIC) (as sources of UK government and other official publications). RESULTS: In total, 32 publications were found in which NMES values were reported and five different methods to estimate NMES were identified. No published method provided sufficient information to clearly differentiate between methods and inadequate detail was given to support replication of any of the methods. Of these five methods, The Ministry of Agriculture, Fisheries and Food (MAFF) have published three different descriptions of methods of NMES estimation used in UK national dietary surveys published since 1989. However, one method has been described consistently in the National Diet and Nutrition surveys published since 1994. CONCLUSIONS: A single, uniform approach to the estimation of NMES for application in nutritional surveys is essential for cross-comparison between surveys. The results show that there is a clear need for one standardized approach for the estimation of NMES in foods.

Acid-etch patterns on the buccal surface of human permanent teeth.

Since the introduction of acid etching to aid adhesion to enamel, there has been much research into dental materials to improve bond strength, but little into the surface topography of etched enamel, particularly regarding possible variations between tooth types. This study was a systematic investigation into the quality and quantity of etch patterns found on the buccal surfaces of different human permanent teeth. Twenty-nine orthodontic patients had high-resolution silicone impressions taken of the buccal surface of incisor, canine, premolar and molar, upper and lower teeth, following etching for 30s with 37% phosphoric acid. Impressions (n=266) were replicated in epoxy resin and examined under high magnification in a scanning electron microscope. A modification of the classification of Galil and Wright was used, with histometric techniques, to quantify the quality of etch patterns on enamel surfaces where orthodontic brackets are typically bonded. There was no difference between right and left or between upper and lower teeth of the same type (P>0.05). There was a general trend toward the increasing occurrence of no etch (type D) from anterior to posterior teeth, and a trend toward fewer good-quality etches (types A and B) in the same direction. Etch types A and B were found to occupy the smallest area on the etched buccal surface enamel. The greatest amount of type A etch 'ideal' was found on the lower incisors, yet it occupied less than 5% of the etched buccal surface enamel. The greatest area of etched enamel surface was occupied by type C (etched, but enamel prisms not evident). It was concluded that there is a significant difference in the acid-etch patterns achieved on different tooth types, which suggests that bond-strength studies should be performed with a single tooth type or that an equal number of different tooth types be included.

Dietary intake of folate by adolescents and the potential effect of flour fortification with folic acid.

The UK Department of Health recently recommended that flour be fortified with folic acid, at 2400 microg/kg. The objectives of the present paper were: to determine the consequence of this on folic acid intake of adolescents; to determine the level of fortification necessary to achieve an intake of 400 microg/d in adolescent girls (the amount recommended periconceptionally); to estimate the consequence of fortification on folic acid intake of high flour consumers; and to report on folate intake of adolescents. Dietary intake of folate and flour were determined by analysis of an existing database of the diets of 379 English adolescents. The folic acid intake that would result from white flour fortification with folic acid at 2400 microg/kg was determined and the level of folic acid fortification necessary to achieve an intake of 400 microg/d in girls from this source was also calculated. Without flour fortification, 6.9 % of girls failed to reach the UK lower reference nutrient intake for total folate. Fortification of white flour with folic acid at 2400 microg/kg would result in an additional folic acid intake of 191(sem 6) microg/d in girls. To ensure 97 % of girls received 400 microg/d from white flour, white flour would need to be fortified at a level of 10 430 microg/kg, resulting in intakes of 1260 microg/d from flour in the highest (97.5 centile) female white flour consumers and 1422 microg/d from flour in the highest (97.5 centile) male white flour consumers.