A reassessment of the dental health of urban Scottish schoolchildren following the cessation of water fluoridation

A comparison was made between the dental health of children in two Scottish towns, one of which was fluoridated until 1983. The mean decayed, missing and filled (dmft) score was found to be 69 per cent lower in 5-year-old children in the fluoridated town compared with the non-fluoridated one and there was a similar 65 per cent difference for DMFT scores in those aged 15 years. 10-year-old children in the fluoridated town had a 39 per cent lower DMFT score, less than the 50 per cent difference found in the 1980 study. Comparison with an identical 1980 study allowed secular trends in caries prevalence to be examined. This revealed a 13 per cent reduction in dmft scores for 5-year-old children and a 16 per cent reduction in DMFT in 10-year-old children in the non-fluoride town. There was a 52 per cent reduction in dmft in 5-year-old children in the previously fluoridated town; however those aged 10 years had a higher DMFT score in 1986 than in 1980. Although this study found that there is a residual benefit from fluoridation in all age groups, there are indications of an adverse trend in dental health in the 10-year-old children in the fluoridated town. The investigation confirmed that the trend is towards lower caries levels amongst Scottish schoolchildren.     

Caries experience among schoolchildren in relation to community fluoridation status and town size

The objective of the present study was to determine the caries experience of schoolchildren aged 7-12 years from the Southeast area of S?o Paulo State, Brazil, in 1998, according to town size and fluoridation status. Data for this cross-sectional study were based on the data bank from the Epidemiological Survey of S?o Paulo State provided by the State Health Department. After stratification by fluoridation status and town size, 29 towns were randomly selected to represent the Southeast area of S?o Paulo State, Brazil, and a total of 13,480 schoolchildren were randomly selected for this study. Calibrated dentists performed dinical examinations according to the WHO criteria. Caries experience and prevalence were significantly lower in fluoridated areas (1.9 DMFT, 2.1 dmft, 20% caries free) than in non-fluoridated areas (2.4 DMFT, 2.4 dmft, 13% caries free). According to town size, DMFT and caries prevalence were significantly higher in small towns (2.3 DMFT, 13% caries free), followed by medium-sized (2.1 DMFT, 17% caries free) and large cities (1.6 DMFT, 27% caries free). Among 12-year-old children, caries prevalence was predominantly moderate or high in small and medium-sized municipalities, whereas in large cities it was moderate or low. The results suggest that water fluoridation is an essential public health measure and that town size may affect caries distribution in the Southeast area of S?o Paulo State.     

Relationship of caries with socioeconomic status in 14-year-old children from communities with different fluoride histories

Abstract The aim of this study was to describe the caries prevalence of 14-yr-old children living in two fluoridated communities, a non-fluoridated community, and a community that discontinued fluoridation 5 yr before the children were examined and to relate the caries prevalence to socio-economic status. Clinical examinations were completed on 413 children of whom 227 had been continuously resident in their towns. Children living in the fluoridated communities had significantly lower mean CMFT and DMFS scores than those in the non-fluoridated town. The children from the town that had discontinued fluoridation 5 yr earlier had mean DMFT and DMFS score that occupied an intermediate position. The differences were greater when only the continuous residents were examined. There were significant differences in the mean DMFT and DMFS when comparing socioeconomic status and fluoridation of the water supply. No interaction effect was demonstrated between these two factors.     

Dental caries experience in Aboriginal and Torres Strait Islanders in the Northern Peninsula Area, Queensland

BACKGROUND: A survey of dental caries experience in children was undertaken in five Aboriginal and Torres Strait Islander communities in the Northern Peninsula Area of Queensland prior to the introduction of water fluoridation. METHODS: Data were obtained from screening dental examinations conducted by the Australian Army as part of a community assistance programme between May and September 2004 from 486 children aged 4-15 years. The clinical examinations were performed in a dental van using a dental chair, light, mirror and probe by a single calibrated examiner. RESULTS: Caries experience was high with a mean 6-year-old dmft of 6.37 and a mean 12-year-old DMFT of 3.50. The 6-year-old dmft Significant Caries Index (SiC) for the third of the population with the highest caries experience was 11.65 and the 12-year-old DMFT SiC was 7.08. Only 15.3 per cent of 6-year-old children had dmft = 0 and 28.9 per cent of 12-year-old children had DMFT = 0. CONCLUSIONS: Dental caries was a significant problem for these remote communities. Aboriginal and Torres Strait Islander children from the Northern Peninsula Area of Queensland had more than four times the caries experience of Australian children for both 6-year-old dmft and 12-year-old DMFT.     

Dental Caries-reducing Effects of a Milk Fluoridation Project in Bulgaria

Objectives: The aim of the present study was to investigate the effects of a community-based milk fluoridation project on dental caries. Methods : Fluoridated milk was provided to about one-half of kindergarten and other schoolchildren in Asenovgrad, a town in the southern part of Bulgaria. The estimated daily milk consumption was 200 ml containing 1 mg of fluoride (～5 ppm F). Cross-sectional samples of 61/2-year-olds in Asenovgrad and Panaguriche (a nearby town selected as the reference community) were examined at the start of the study in 1988 and after three years. Additional cross-sectional samples of 7 1/2-year-olds in Asenovgrad who were and were not drinking fluoridated milk were examined at baseline and at three years to provided an internal control group. Samples of 6 1/2-and 8 1/2-year-olds from Asenovgrad and Karlovo were examined in 1993 to provide for five-year follow-up comparisons. Results : In 6 1/2-year-old children who had consumed fluoridated milk for three years, there was a decrease in the mean dmft per child of 40 percent and in the mean DMFT of 89 percent compared to children examined at baseline. Children in Asenovgrad who were 4 1/2 years old at the start of the study and had been drinking fluoridated milk for three years had on average 44 percent fewer dmft and 83 percent fewer DMFT at 7 1/2 years of age than those not drinking fluoridated milk. After five years the dmft index was 40 percent less and the DMFT index 79 percent less in those children who had participated in the full five years of the program compared to the control group. Conclusions : Results seem to confirm the caries-reducing effects of milk fluoridation found in previous studies. Unexpected large caries reductions obtained in this nonexperimental study, however, probably cannot be attributed to the fluoridation of milk alone. The mere introduction of the project might have led to other changes affecting dental caries, such as improved oral hygiene and better dietary habits.     

Prevalence and severity of dental caries in Costa Rican schoolchildren: results of the 1999 national survey

In 1987, Costa Rica implemented a comprehensive national salt fluoridation programme using sodium fluoride (225-275mg F/kg salt). AIM: To describe dental caries prevalence and severity in Costa Rican children in 1999. METHODS: Eight calibrated examiners (inter-examiner Kappa = 0.70 or higher) recorded information on dental caries, treatment needs, enamel fluorosis, and dentofacial anomalies for schoolchildren aged 6-8,12, and 15-years (N=3758). The survey utilised a multistrata probability sample with fixed allocation to represent seven regions of the country. RESULTS: The overall mean dmft for age 6-8 years was 3.32. The DMFT for age 12 was 2.46 and for age 15 was 4.37. Regional differences were observed; for example, the DMFT at age 12 years ranged from 1.93 to 3.86. Compared with pre-fluoridation data collected in 1984, schoolchildren aged 12 years, experienced a 28 per cent decrease in caries prevalence (100 per cent to 72 per cent) and a 73 per cent decrease in severity (DMFT from 9.13 to 2.46, representing an 8.3 per cent compound annual per cent reduction). CONCLUSIONS: Between 1984 and 1999, Costa Rican schoolchildren experienced substantial reductions in caries prevalence and severity. Many factors may be involved in this decline, but the most important appears to be exposure to fluoridated salt.     

Dental caries and enamel fluorosis among the fluoridated and non-fluoridated populations in the Republic of Ireland in 2002

BACKGROUND: A national survey of oral health of children and adolescents was carried out in the Republic of Ireland (RoI) in 2001/2002. AIMS: To compare the prevalence of caries between child and adolescent residents in fluoridated and non-fluoridated communities in the RoI whilst controlling for disadvantage. To compare caries levels amongst disadvantaged and non-disadvantaged groups with and without water fluoridation. To report the changes in caries levels between the 1960s and 2002 in RoI. To report the changes in dental fluorosis levels between 1984 and 2002. METHODOLOGY: Cross sectional oral health survey of a representative, random, stratified sample of 17,851 5-, 8-, 12- and 15-year-old children and adolescents in RoI. WHO examination criteria with the addition of visible, non-cavitated dentine caries were used for recording caries. Fluorosis was measured using Dean's Index. RESULTS: In the RoI the mean dmft/DMFT scores for 5-, 8-, 12-, and 15-year-olds were 1.2, 0.3, 1.1 and 2.3. For those with domestic water fluoridation since birth the scores were 1.0, 0.3, 1.1 and 2.1 respectively. In non-fluoridated areas of RoI the mean dmft/DMFT scores for 5-, 8-, 12-, and 15-year-olds was 1.7, 0.3, 1.3 and 3.2, respectively. For 5-, 12- and 15-year-old age groups dental caries levels were lower amongst children with fluoridated domestic water supplies (all p<0.0001). The prevalence of dental fluorosis has increased in RoI since 1984. 23% and 36% of 8- and 15-year olds respectively in fluoridated areas had Dean's Index scores at the questionable or greater level in 2002, compared with 6% and 5% respectively in 1984. CONCLUSIONS: Caries levels are lower among children with fluoridated domestic water supplies. Decay levels are much lower in 2002 than they were in 1984 and in the 1960s. The oral health of the less well off is worse than that of the rest of the population. The prevalence of dental fluorosis is higher amongst children and adolescents with fluoridated water supplies. Comparisons with 1984 data show an increase in the prevalence of fluorosis since that time.     

Reassessment of the effect of fluoridation on cost of dental treatment among Scottish schoolchildren

The present study, which is a repeat of a 1980 study, compares the dental treatment needs of 5, 10, and 15-yr-old life-time residents of a fluoridated town (Stranraer) and non-fluoridated town (Annan). Although fluoridation ceased in July 1983, the cost of all dental treatment in 1986 was 57% lower for 5-yr-olds in the fluoride area compared with the non-fluoride one. The corresponding differences in costs for 10- and 15-yr-old groups were 36% and 63%, respectively. Comparison with the 1980 results showed a 21% drop in the cost of all treatment for 5-yr-olds in Annan and a 4% drop in 10-yr-olds. The corresponding comparison for Stranraer 5-yr-olds showed a 43% reduction in the cost of all treatment. The 10-yr-old group in Stranraer showed a 21% increase in the cost of all treatment and a 115% increase in the cost of restorations for caries. The implications of these findings and the possible link with the cessation of water fluoridation are discussed.     

Caries risk in patients with thalassaemia major

AIM: The aim of this study was to assess the prevalence and distribution of dental caries in subjects with thalassaemia major. DESIGN: Clinical examination for dental caries, diagnosed according to the WHO criteria. PARTICIPANTS: A total of 54 thalassaemic patients, 23 aged 6-9 (14 males and 9 females) and 31 aged 12-18 (17 males and 14 females) were examined. OUTCOME MEASURES: dmft, DMFT and plaque scores. RESULTS: The mean dmft was 6.92 for 6-7 year olds and 4.72 for 8-9 year olds. The DMFT values were 6.57 and 5.95 for ages 12-14 and 15-18, respectively. There was no statistically significant difference in caries prevalence (dmft/DMFT) between gender or between primary and permanent teeth. Only 17.4 per cent of the children aged 6-9 and 21.4 per cent of 12-18 years olds were caries free. The prevalence of dental caries in the thalassaemia patients was considerably higher (22.7 per cent) than that reported in a normal Jordanian sample (DMFT 6.26 vs 4.84). Very few fillings (1.4 per cent of the examined teeth) were observed, indicating a negligible rate of conservative treatment. More than half (61.1 per cent) of the patients had poor oral hygiene (plaque score > or = 2.0). CONCLUSIONS: The need for effective preventive measures, education and dental treatment need to be stressed for this caries risk group.     

The prevalence of caries in 5-year-old children living in fluoridated and non-fluoridated communities in New Zealand.

The prevalence of caries in 5-year-old children living in fluoridated and non-fluoridated communities was investigated. Clinical examinations were completed on 342 children, of whom 247 had been continuously resident in their towns. Children living in fluoridated communities had significantly lower mean dmft and dmfs than children living in non-fluoridated communities. There was a marked social gradient in the non-fluoridated communities, which was not observed in the children from the fluoridated communities.     

Caries experience of 5-6-year-old and 12-13-year-old schoolchildren in central and western Nepal

OBJECTIVE: To describe and analyse the caries experience and caries prevalence in the deciduous dentition of 5-6-year-old schoolchildren and in the permanent dentition of 12-13-year-old schoolchildren in western and central Nepal. Design: Non-randomised cross-sectional surveys conducted by trained and calibrated examiners. SETTING: Surveys were conducted in private and government rural and urban schools at 10 sites along the Terai and the foothills in eight districts of western and central Nepal. SUBJECTS: A total of 2,177, 5-6-year-old and 3,323, 12-13-year-old schoolchildren from urban and rural areas were examined under WHO Pathfinder methodology. OUTCOME MEASURES: Prevalence of caries and dental caries experience (dmft/DMFT). RESULTS: The caries prevalence and mean dmft score of 5-6-year-olds was 67% and 3.3 (urban 64% and 2.9; rural 78% and 4.0). The caries prevalence and mean DMFT score of 12-13-year-olds was 41% and 1.1 (urban 35% and 0.9; rural 54% and 1.5). The d/D-component constituted almost the entire dmft/DMFT index. CONCLUSION: The recorded prevalence of untreated dental caries in schoolchildren requires an appropriate oral health response based primarily on prevention and health promotion. Foremost in this regime would be the promotion and use of accessible and affordable fluoridated toothpaste.     

Caries experience and oral hygiene status of blind, deaf and mentally retarded female children in Riyadh, Saudi Arabia.

OBJECTIVE: To determine the caries experience and oral hygiene status in blind, deaf and mentally retarded female children in Riyadh, Saudi Arabia. METHOD: All (N=218) the 6-7-year-old and 11-12-year-old blind, deaf and mentally retarded female children registered with the Presidency of Girls' Education schools in Riyadh were examined for dental caries and oral hygiene in a dental operatory setting. RESULTS: All (100%) the blind 6-7-year-old had caries with a mean dmft score of 6.58 (SD 2.02). The caries prevalence in blind 11-12-year-olds was 88.2% with a mean DMFT score of 3.89 (SD 2.67). Among 6-7-year-old blind children 8.3 %, and in 11-12-year-old blind children 29.4% had good oral hygiene. The caries prevalence in deaf 6-7-year-olds was 95.7% with a mean dmft score of 7.35 (SD 3.51). The caries prevalence in 11-12-year-old deaf children was 93% with a mean DMFT of 5.12 (SD 3.45). Less than one-fifth (17.4%) of the 6-7-year-old deaf children and only 7.0% of 11-12-year-old deaf children had good oral hygiene. The caries prevalence in mentally retarded 6-7-year-old was 93.9% with a mean dmft of 8.00 (SD 4.1). All the mentally retarded 11-12-year-old had carious teeth with a mean DMFT score of 5.81 (SD 2.95). Only 3.1% of the mentally retarded 6-7-year-old and none of the mentally retarded 11-12-year-olds had good oral hygiene. CONCLUSIONS: Caries prevalence and severity in all the three groups of female special children were very high, and the number of children with good oral hygiene was very low.     

The relationship between water fluoridation and socioeconomic deprivation on tooth decay in 5-year-old children.

AIM: To examine the relationship between water fluoridation, socioeconomic deprivation and tooth decay in 5-year-olds. SETTING: 10,004 children: 1,051 in naturally fluoridated Hartlepool in 1991/92, 3,816 in fluoridated Newcastle & North Tyneside and 5,137 in non-fluoridated Salford & Trafford in 1993/94. OUTCOME MEASURES: Correlations between mean electoral ward dmft and ward Townsend Scores from the 1991 census. RESULTS: Regardless of the level of water fluoridation significant correlations were found between deprivation and tooth decay. Multiple linear regression models for dmft showed a statistically significant interaction between ward Townsend score, and both types of water fluoridation, confirming the more deprived the area the greater the reduction in tooth decay. At a Townsend score of zero (the English average) there was a predicted 43% reduction in decay in 5-year-olds in fluoridated areas. CONCLUSIONS: Tooth decay is strongly associated with social deprivation. The findings confirm that the implementation of water fluoridation has halved tooth decay in 5-year-old children and that the dental caries divide between rich and poor is reduced.     

Brisbane Dental Survey, 1977 A comparative study of caries experience of children in Brisbane, Australia over a 20-year period

A dental survey of 1,002 children aged 6, 8, 10, 12 and 14 years was carried out in Brisbane using criteria and methods of the World Health Organization. Mean DMFT per child were substantially lower than expected for a non-fluoridated area, being 0.7, 2.0, 3.1, 4.7 and 7.2 for the respective age groups. These scores represent a 50% reduction on levels reported in 1954 and a 20-35% reduction on caries experience of Queensland country children in 1967. 21% of the sample consumed fluoride tablets regularly and these had caries levels virtually identical with life-time residents of fluoridated areas. Compared with children never taking tablets they had 58-79% fewer dmft and 28-54% fewer DMFT. From data of a study of Townsville in 1975 after 10 years' fluoridation it can be calculated that there would be approximately 180,000 fewer restorations required in Brisbane if that city had been fluoridated 10 years previously.     

Cessation of fluoridation of drinking water; results of caries research in Tiel and Culemborg in the period of 1968-1988

In December 1973 water fluoridation was discontinued in Tiel, the Netherlands. Six years later an epidemiological study was started, with the aim to investigate the consequences. In the period from 1979 to 1988 a yearly caries investigation was carried out in 15 year old children born and living in Tiel and children living in the control town of Culemborg, where the drinking water had never been fluoridated. The 15 year old children in 1979-1980 in Tiel had a 18% higher caries experience than the same age group in 1968-1969, to whom fluoridated water had been available from birth onward. In the same period a 28% decrease of the caries was found in Culemborg. In 1979-1980 the DMFS-index in Tiel was still 36% lower than in Culemborg. Between 1979-1980 and 1987-1988 the caries experience decreased in both towns.     

Dental Caries of Lifetime Residents in Baixo Guandu, Brazil, Fluoridated since 1953 – A Brief Communication

Objectives: This study aimed to verify the dental caries prevalence in Baixo Guandu, the first Brazilian city to fluoridate its public water supplies; to compare the findings with the data from the national survey; and also to compare the prevalence in the 12-year-old age group with the data obtained before the beginning of the fluoridation. Methods: All the lifetime residents aged 5, 12, 15 to 19, and 35 to 44 years old were clinically examined (World Health Organization). Results: The means of dmft/DMFT were lower than in the Brazilian population living in fluoridated communities. The DMFT Index in 12-year-old residents decreased between 1953 and 2005 from 8.61 to 1.55. Conclusions: The addition of fluoride to public water supplies was an important ally in the improvement of the oral health of Baixo Guandu inhabitants.     

A comparison of dental caries levels in two communities with different oral health prevention strategies stratified in different social classes

OBJECTIVES: To compare dental caries levels of schoolchildren stratified in different social classes whose domestic water supply had been fluoridated since birth (Dublin) with those living in an area where fluoridated salt was available (Freiburg). METHODS: A representative, random sample of twelve-year-old children was examined and dental caries was recorded using World Health Organization criteria. RESULTS: A total of 699 twelve-year-old children were examined, 377 were children in Dublin and 322 in Freiburg. In Dublin the mean decayed, missing, and filled permanent teeth (DMFT) was 0.80 and in Freiburg it was 0.69. An examination of the distribution of the DMFT score revealed that its distribution is highly positively skewed. For this reason this study provides summary analyses based on medians and inter-quartile range and nonparametric rank sum tests. In both cities caries levels of children in social class 1 (highest) were considerably lower when compared with the other social classes regardless of the fluoride intervention model used. The caries levels showed a reduced disparity between children in social class 2 (medium) and 3 (lowest) in Dublin compared with those in social class 2 and 3 in Freiburg. CONCLUSIONS: The evidence from this study confirmed that water fluoridation has reduced the gap in dental caries experience between medium and lower social classes in Dublin compared with the greater difference in caries experience between the equivalent social classes in Freiburg. The results from this study established the important role of salt fluoridation where water fluoridation is not feasible.     

Dental caries of lifetime residents in Baixo Guandu, Brazil, fluoridated since 1953--a brief communication

OBJECTIVES: This study aimed to verify the dental caries prevalence in Baixo Guandu, the first Brazilian city to fluoridate its public water supplies; to compare the findings with the data from the national survey; and also to compare the prevalence in the 12-year-old age group with the data obtained before the beginning of the fluoridation. METHODS: All the lifetime residents aged 5, 12, 15 to 19, and 35 to 44 years old were clinically examined (World Health Organization). RESULTS: The means of dmft/DMFT were lower than in the Brazilian population living in fluoridated communities. The DMFT Index in 12-year-old residents decreased between 1953 and 2005 from 8.61 to 1.55. CONCLUSIONS: The addition of fluoride to public water supplies was an important ally in the improvement of the oral health of Baixo Guandu inhabitants.     

Dental caries trends among indigenous and non-indigenous Australian children

OBJECTIVE: To examine trends in dental caries among indigenous and non-indigenous children in an Australian territory. BASIC RESEARCH DESIGN: Routinely-collected data from a random selection of 6- and 12-year-old indigenous and non-indigenous children enrolled in the Northern Territory School Dental Service from 1989-2000 were obtained. The association of indigenous status with caries prevalence (percent dmft or DMFT>0 and percent dmft>3 or DMFT>1), caries severity (mean dmft or DMFT) and treatment need (percent d/dmft or D/DMFT) was examined. RESULTS: Results were obtained for 10,687 6- and 12-year old indigenous children and 21,777 6- and 12-year-old non-indigenous children from 1989-2000. Across all years, indigenous 6-year-olds had higher caries prevalence in the deciduous dentition, greater mean dmft and percent d/dmft, and indigenous 12-year-olds had greater percent D/DMFT than their non-indigenous counterparts (p<0.05). From 1996-2000 the mean dmft and percent d/dmft for indigenous 6-year-olds and mean DMFT and percent D/DMFT for indigenous 12-year-olds increased, yet remained relatively constant for their non-indigenous counterparts (p<0.05). From 1997-2000, the percent dmft>3 for 6-year-old indigenous children was more than double that of non-indigenous children, while across the period 1994-2000, indigenous 6-year-old mean dmft was more than double that of their non-indigenous counterparts (p<0.05). CONCLUSIONS: Indigenous children in our study experienced consistently poorer oral health than non-indigenous children. The severity of dental caries among indigenous children, particularly in the deciduous dentition, appears to be increasing while that of non-indigenous children has remained constant. Our findings suggest that indigenous children carry a disproportionate amount of the dental caries burden among Northern Territory 6- and 12-year-olds.     

Caries prevalence in 6-, 11- and 14-year-old children in the Cyclades Islands, Greece

Following the World Health Organization criteria, a total of 1,604 out of 3,225 children aged 6, 11 and 14 years living on the 20 islands of the Cyclades complex were examined. Recordings showed that in the 6-year-old children, the mean dmft index was 2.21 (SD=3.00) with 46% caries free. In the 11-year-old children, the DMFT averaged 1.39 (SD=1.78) with 46% caries free. In the 14-year-old children, the mean DMFT was 2.62 (SD=2.83) with 32% caries free. Statistically significant differences were found in the DMFT of the 11- and 14-year-old subjects living in naturally water fluoridated and non-fluoridated areas. According to these data, it appears that the first two WHO targets for the year 2000 are almost fulfilled.